Vehicle notification system

Abstract

In a case where a right turning vehicle VA and a straight traveling vehicle VB are present and a right turn intention of the right turning vehicle VA is detected, a vehicle notification system 1 sets a virtual intersection area VACS including a virtual intersection center VCTR at which a center line CL on a load and a right turning path TRa' where the right turning vehicle VA turns right at the predetermined section intersect, and a virtual predicted collision area VACP including a virtual predicted collision point VCPP where the right turning path TRa' and a straight traveling path TRb' of the straight traveling vehicle VB travels intersect. At each of third and fourth notification issuance timings set according to a behavior of the right turning vehicle VA with respect to the virtual intersection area VACS and the virtual collision prediction area VACP, a notification issuance in a predetermined mode is performed when a notification issuance condition defined in regard to a position of the traveling vehicle VB is met.

Description

BACKGROUND OF THE INVENTIONField of the Invention

[0001] Embodiments of the present invention relate to a vehicle notification system.Description of the Related Art

[0002] For the purpose of assisting driving in situations where right turn is made at intersections on left-hand traffic roads, there is a technology of recognizing operation statuses of other traffic participants including oncoming vehicles moving straight ahead toward intersections in opposite lanes and providing an instruction for a right turn timing that allows a driver to avoid collisions against the oncoming vehicles to the driver.

[0003] Here, detection of traffic participants is typically performed by in-vehicle sensors such as cameras or radars.

[0004] [Patent Document 1] JP 2009-265832 A

[0005] However, it is difficult for in-vehicle sensors to detect traffic participants who are present at blind angles such as behind obstacles.

[0006] Specifically, in a case where there is another vehicle traveling side by side with an oncoming vehicle in the same lane, or in a case where another vehicle is stopping to wait for turning right in front of the oncoming vehicle, the vehicle may become an obstacle, and the oncoming vehicle may be present at a blind angle of the vehicle, which may make it difficult to detect the oncoming vehicle depending on an in-vehicle sensor equipped in the right turning vehicle.

[0007] In a case where the vehicle that may become an obstacle is a large vehicle, the blind angle becomes wider, which makes it more difficult to detect the oncoming vehicle.

[0008] Moreover, a situation where a right turning vehicle and a straight traveling vehicle, which is an oncoming vehicle thereto, are present is not necessarily limited to an intersection. A case of a two-way road in which a straight traveling vehicle advances straight in an opposite lane and a right turning vehicle turns right into a store such as a convenience store or a residential property located on a roadside along the opposite lane, for example, is assumed. In this case, driving assistance is needed in a situation in which the right turning vehicle turns right at a location other than an intersection of the road, that is, the right turning vehicle crosses the opposite lane.SUMMARY OF THE INVENTION

[0009] Thus, an object of the present invention is to provide a vehicle notification system that can assist driving even in situations of turning right at a location other than intersections of roads and contribute to a further improvement in traffic safety.

[0010] To achieve the above-mentioned object, a vehicle notification system issues notifications for traffic participants including a first vehicle that is present in a traveling lane leading to a predetermined section on a road in order to turn right or left at the predetermined section and a second vehicle that is traveling in a straight direction on a lane opposite to the traveling lane toward the predetermined section. The vehicle notification system includes: a road map storage unit that stores a road map including the predetermined section and specifies a current position of the first vehicle on the road map and a current position of the second vehicle on the road map; a direction-change-intention detection unit that detects a direction change intention of the first vehicle turning right or left at the predetermined section; a virtual area setting unit that in a case where a specification result of the road map storage unit shows that the first vehicle and the second vehicle are present and the direction-change-intention detection unit detects the direction change intention, regards, as a virtual intersection center, a point at which a turning path that is a path where the first vehicle travels when the first vehicle turns right or left at the predetermined section and enters a predetermined area located on a roadside along the opposite lane of the road and a center line that sections the traveling lane and the opposite lane intersect, regards, as a virtual predicted collision point, a point where the turning path and a straight traveling path that is a path where the second vehicle travels intersect, and sets a virtual intersection area including the virtual intersection center and a virtual predicted collision area including the virtual predicted collision point in an associated manner in the road map; a third vehicle behavior detection unit that sets, as a third notification issuance timing, a timing at which presence of the first vehicle at a predetermined position relative to the virtual intersection area set by the virtual area setting unit is detected on the basis of the current position of the first vehicle specified by the road map storage unit; a fourth vehicle behavior detection unit that sets, as a fourth notification issuance timing that is different from the third notification issuance timing, a timing at which traveling of the first vehicle toward the virtual predicted collision point inside the virtual intersection area or presence of the first vehicle inside the virtual predicted collision area is detected after the third vehicle behavior detection unit sets the third notification issuance timing; a first notification issuing unit that performs notification issuance in a third predetermined mode for the traffic participants under a condition that a third predetermined notification issuance condition defined in advance in regard to a position of the second vehicle is met at the third notification issuance timing set by the third vehicle behavior detection unit; and a second notification issuing unit that performs notification issuance in a fourth predetermined mode for the traffic participants under a condition that a fourth predetermined notification issuance condition defined in advance in regard to the position of the second vehicle is met at the fourth notification issuance timing set by the fourth vehicle behavior detection unit.

[0011] To achieve the above-mentioned object, a vehicle notification system performs notification issuance for traffic participants including a first vehicle and a second vehicle traveling in a lane opposite to a lane where the first vehicle is traveling in a traffic situation where the first vehicle and the second vehicle are present. The vehicle notification system includes: a road map storage unit that stores a road map; a first vehicle position specification unit that specifies a current position of the first vehicle on the road map; a second vehicle position specification unit that specifies a current position of the second vehicle on the road map; a direction-change-intention detection unit that detects a direction change intention of the first vehicle turning right or left; a virtual area setting unit that sets a virtual area that overlaps a path where the first vehicle travels when the first vehicle turns right or left on the road map corresponding to a section between the first vehicle and the second vehicle in a case where the direction-change-intention detection unit detects the direction change intention; a notification issuance timing setting unit that sets a notification issuance timing in accordance with a position of the first vehicle relative to the virtual area set by the virtual area setting unit; and a notification issuing unit that performs notification issuance in a predetermined mode for the traffic participants under a condition that a predetermined notification issuance condition defined in regard to a position of the second vehicle is met at the notification issuance timing set by the notification issuance timing setting unit.EFFECTS OF THE INVENTION

[0012] According to one aspect of the present invention, it is possible to provide a vehicle notification system that can assist driving even in situations of turning right at a location other than intersections of roads and contribute to a further improvement in traffic safety.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Fig. 1 is a schematic diagram illustrating an overall configuration of a vehicle notification system according to an embodiment of the present invention; Fig. 2 is a schematic diagram illustrating an internal configuration of a controller included in a right turning vehicle; Fig. 3 is a schematic diagram illustrating an internal configuration of a controller included in a straight traveling vehicle; Fig. 4 is a flowchart illustrating an overall flow of notification control performed in the right turning vehicle that turns right at an intersection; Fig. 5 is a flowchart illustrating content of the notification control (information presentation processing) performed in the right turning vehicle that turns right at the intersection; Fig. 6 is a flowchart illustrating content of the notification control (alarm processing) performed in the right turning vehicle that turns right at the intersection; Fig. 7 is a flowchart illustrating an overall flow of notification control performed in the straight traveling vehicle that travels straight across the intersection; Fig. 8 is a flowchart illustrating content of the notification control (information presentation processing) performed in the straight traveling vehicle that travels straight across the intersection; Fig. 9 is a flowchart illustrating content of the notification control (alarm processing) performed in the straight traveling vehicle that travels straight across the intersection; Fig. 10 is an explanatory diagram illustrating a method of calculating an information presentation distance and an alarm distance; Fig. 11 is a schematic diagram illustrating an example of a traffic situation at the intersection, the traffic situation being assumed to be a target of a notification; Fig. 12 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an information presentation issuance timing at the intersection; Fig. 13 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an alarm issuance timing at the intersection; Fig. 14 is a schematic diagram illustrating a situation at the intersection after the straight traveling vehicle passes the intersection; Fig. 15 is a flowchart illustrating an overall flow of notification control performed in the right turning vehicle that turns right at a virtual intersection; Fig. 16 is a flowchart illustrating content of the notification control (information presentation processing) performed in the right turning vehicle that turns right at the virtual intersection; Fig. 17 is a flowchart illustrating content of the notification control (alarm processing) performed in the right turning vehicle that turns right at the virtual intersection; Fig. 18 is a flowchart illustrating an overall flow of notification control performed in the straight traveling vehicle that travels straight across the virtual intersection; Fig. 19 is a flowchart illustrating content of the notification control (information presentation processing) performed in the straight traveling vehicle that travels straight across the virtual intersection; Fig. 20 is a flowchart illustrating content of the notification control (alarm processing) performed in the straight traveling vehicle that travels straight across the virtual intersection; Fig. 21 is a schematic diagram illustrating an example of a traffic situation at the virtual intersection, the traffic situation being assumed to be a target of a notification; Fig. 22 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an information presentation issuance timing at the virtual intersection; Fig. 23 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an alarm issuance timing at the virtual intersection; Fig. 24 is a schematic diagram illustrating a situation after the straight traveling vehicle passes the virtual intersection; Fig. 25 is a schematic diagram illustrating a right turning path of the right turning vehicle set by a virtual area setting unit; and Fig. 26 is a schematic diagram illustrating virtual intersection area candidates and virtual predicted collision area candidates generated by the virtual area setting unit. DETAILED DESCRIPTION

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the same reference signs are given to identical or equivalent components in each figure.(Overall Configuration of Vehicle Notification System)

[0015] Fig. 1 is a schematic diagram illustrating a configuration of a vehicle notification system (hereinafter, simply referred to as a "notification system" in some cases) 1 according to an embodiment of the present invention.

[0016] In the present embodiment, a traffic situation where a vehicle (hereinafter, referred to as a "right turning vehicle") VA traveling toward a predetermined section (predetermined location) on a left-hand traffic road in order to turn right at the predetermined section and another vehicle (hereinafter, referred to as a "straight traveling vehicle") VB traveling in a straight direction toward the predetermined section in a lane (hereinafter, referred to as an "opposite lane" in some cases) opposite to a lane (hereinafter, referred to as a "traveling lane" in some cases) in which the right turning vehicle VA is traveling are present is assumed. The notification system 1 can be applied not only to left-hand traffic roads but also to right-hand traffic roads. In a case of right-hand traffic, a traffic situation where a left turning vehicle traveling in a traveling lane toward a predetermined section and a straight traveling vehicle traveling toward the predetermined section in an opposite lane are present is assumed to be a target. In other words, the notification system 1 can be applied to traffic situations where a right or left turning vehicle (hereinafter, referred to as a "right or left turning vehicle" or a "non-straight traveling vehicle") in a traveling lane and a straight traveling vehicle in an opposite lane are present together. In a case of left-hand traffic, the right turning vehicle is a vehicle turning right at the predetermined section and should not hinder the straight traveling vehicle traveling in the opposite lane from passing the predetermined section.

[0017] In the present embodiment, both intersections and locations other than intersections are assumed as predetermined sections of roads. For convenience of the following explanation, locations other than intersections may be regarded as virtual intersections and may be referred to as "virtual intersections" below.

[0018] As illustrated in Fig. 1, the notification system 1 includes, as main elements related to the present embodiment, auxiliary devices such as vehicle sensors 111 to 113, communication devices 121 and 122, and a human machine interface (HMI) device 131 in addition to a controller 101.

[0019] In the present embodiment, various elements including the controller 101 are provided in each of the right turning vehicle VA and the straight traveling vehicle VB. A controller 101a included in the right turning vehicle VA and a controller 101b included in the straight traveling vehicle VB configure one virtual controller constituting the notification system 1 through mutual cooperation. It is a matter of course that the notification system 1 can be configured as an in-vehicle system for the right turning vehicle VA by the controller 101a included in the right turning vehicle VA and the auxiliary devices thereof and can also be configured as an in-vehicle system for the straight traveling vehicle VB by the controller 101b included in the straight traveling vehicle VB and the auxiliary devices thereof.

[0020] In the following description, vehicle-to-vehicle communication is performed between the right turning vehicle VA and the straight traveling vehicle VB to allow vehicle information related to the right turning vehicle VA to be shared between the right turning vehicle VA and the straight traveling vehicle VB and allow vehicle information related to the straight traveling vehicle VB to be shared between both the vehicles VA and VB. In the present embodiment, the vehicle information to be communicated or shared between the right turning vehicle VA and the straight traveling vehicle VB includes current positions Pa and Pb, vehicle speeds VSPa and VSPb, operating statuses of right turn signals (that is, outputs of right turn signal switches), and lane IDs of the vehicles VA and VB. The vehicle information to be communicated or shared between the right turning vehicle VA and the straight traveling vehicle VB may include destination information and a steering amount for each of the vehicles VA and VB. The communication between the right turning vehicle VA and the straight traveling vehicle VB is not limited to direct communication via vehicle-to-vehicle communication and may also be performed indirectly through roadside equipment installed at roadsides, servers disposed remotely, communication devices included in vehicles other than the right turning vehicle VA and the straight traveling vehicle VB.

[0021] In the present embodiment, the right turning vehicle VA and the straight traveling vehicle VB constitute the notification system 1 with similar basic configurations. The right turning vehicle VA includes the controller 101a and also includes vehicle sensors 111a, 112a, and 113a, communication devices 121a and 122a, and an HMI device 131a. On the other hand, the straight traveling vehicle VB includes the controller 101b and also includes vehicle sensors 111b, 112b, and 113b, communication devices 121b and 122b, and an HMI device 131b.

[0022] The right turning vehicle VA and the straight traveling vehicle VB include steering angle sensors 114a and 114b, and navigation devices 115a and 115b.

[0023] The controllers 101a and 101b constitute a calculation unit of the notification system 1 and generate and output a command signal in accordance with results of calculation. The controllers 101a and 101b are configured of microcomputers including central processing units (CPUs), storage devices such as ROMs and RAMs, and input / output interfaces.

[0024] The vehicle sensors 111a to 113a and 111b to 113b constitute a detection unit of the notification system 1. The right turning vehicle VA includes a position sensor 111a, a vehicle speed sensor 112a, and a right turn signal switch 113a as the accompanying vehicle sensors, while the straight traveling vehicle VB includes a position sensor 111b, a vehicle speed sensor 112b, and a right turn signal switch 113b as the accompanying vehicle sensors.

[0025] The position sensor 111a detects the current position Pa of the right turning vehicle VA, and the position sensor 111b detects the current position Pb of the straight traveling vehicle VB. Both the position sensors 111a and 111b can be configured of global navigation satellite system (GNSS) receivers and detect the current positions of the target vehicles VA and VB with latitude and longitude coordinates Pa (Pai, Paj) and Pb (Pbi, Pbj).

[0026] The vehicle speed sensor 112a detects the traveling speed (hereinafter, referred to as a "vehicle speed") VSPa of the right turning vehicle VA, while the vehicle speed sensor 112b detects the vehicle speed VSPb of the straight traveling vehicle VB. The vehicle speed sensors 112a and 112b can perform the detection by detecting wheel speeds (for example, rotation speeds of driven wheels) of the target vehicles VA and VB and converting the wheel speeds into traveling distances per unit time using tire dynamic radii or the like.

[0027] The right turn signal switch 113a outputs an on signal when a right direction indicator (hereinafter, referred to as a "right turn signal") included in the right turning vehicle VA is activated, and the right turn signal switch 113b outputs an on signal when the right turn signal included in the straight traveling vehicle VB is activated. The operations of the right turn signal switches 113a and 113b indicate that the target vehicles VA and VB intend to turn right on the road or change lanes.

[0028] Detection signals from the position sensor 111a, the vehicle speed sensor 112a, and the right turn signal switch 113a of the right turning vehicle VA are output to the controller 101a of the right turning vehicle VA, while detection signals from the position sensor 111b, the vehicle speed sensor 112b, and the right turn signal switch 113b of the straight traveling vehicle VB are output to the controller 101b of the straight traveling vehicle VB.

[0029] The HMI devices 131a and 131b constitute an output unit of the notification system 1. The HMI device 131a receives a command signal from the controller 101a and provides a notification related to a traffic situation to a driver of the right turning vehicle VA. The HMI device 131b receives a command signal from the controller 101b and provides a notification related to the traffic situation to a driver of the straight traveling vehicle VB.

[0030] The notifications may be provided by the HMI devices 131a and 131b visually or auditorily. The HMI devices 131a and 131b can provide both display and sound notifications and can also provide notifications using one of them. The HMI devices 131a and 131b are disposed at locations that allow the drivers to easily view the HMI devices 131a and 131b, such as on dashboards in the vehicles.

[0031] The steering angle sensors 114a and 114b detect angles at which wheels involved in steering, typically front wheels of the vehicles VA and VB are directed, that is, wheel direction angles (hereinafter, referred to as "steering angles"). The steering angles are angles formed between vertical planes perpendicular to rotation axes of the front wheels and vertical planes extending in the front-rear directions of the vehicles VA and VB. It is possible to acquire situations of steering and steering information of the vehicles VA and VB by the steering angle sensors 116a and 116b.

[0032] The navigation devices 115a and 115b guide route to destinations set by the drivers, on the basis of the current positions Pa and Pb of the vehicles VA and VB input from the position sensors 111a and 111b and the map information. The route guidance is performed by displaying maps, traveling routes, the current positions Pa and Pb of the vehicles VA and VB, and traveling directions on HMI devices 131a and 131b, for example. The traveling directions indicated in the route guidance include traveling straight, turning right, and turning left.

[0033] In addition to the above, the right turning vehicle VA includes a transmitter 121a and a receiver 122a, while the straight traveling vehicle VB includes a transmitter 121b and a receiver 122b. The transmitter 121a and the receiver 122a included in the right turning vehicle VA constitute a vehicle-to-vehicle communication device of the right turning vehicle VA, while the transmitter 121b and the receiver 122b included in the straight traveling vehicle VB constitute a vehicle-to-vehicle communication device of the straight traveling vehicle VB. The right turning vehicle VA and the straight traveling vehicle VB can perform wireless communication via the mutual vehicle-to-vehicle communication devices.

[0034] As mentioned earlier, the communication between the right turning vehicle VA and the straight traveling vehicle VB is not limited to direct communication between the right turning vehicle VA and the straight traveling vehicle VB and may also be indirect communication via roadside equipment, remote servers, other vehicles, or the like.

[0035] Hereinafter, traffic situations assumed in the present embodiments will be described, divided into a case of the intersections and a case of the virtual intersection.

[0036] Fig. 11 is a schematic diagram illustrating an example of a traffic situation at the intersection, the traffic situation being assumed to be a notification target according to the present embodiments.

[0037] In the present embodiment, a traffic situation in which the right turning vehicle VA and the straight traveling vehicle VB face each other with an intersection CS interposed therebetween is assumed. The intersection (a cross intersection in the present embodiment) CS is present on a road R with two lanes on each side including right turn lanes L11 and L21 and straight lanes L12 and L22. The right turning vehicle VA is present in the right turn lane L11 on one side and is approaching the intersection CS, while the straight traveling vehicle VB is present in the straight lane L22 on the other side and is traveling at a position separated from the intersection CS in a straight direction toward the intersection CS. Here, the right turn lane L11 corresponds to the traveling lane of the right turning vehicle VA, and the right turn lane L21 and the straight lane L22 correspond to lanes opposite to the right turning vehicle VA. The right turn lane L21 and the straight lane L22 as the opposite lanes may be referred to as an "opposite right turn lane" and an "opposite straight lane" below.

[0038] In addition to the right turning vehicle VA and the straight traveling vehicle VB, a vehicle (hereinafter, referred to as a "waiting vehicle") VC stopping to wait for turning right is present before a stop line SL2 in front of the straight traveling vehicle VB in the opposite right turn lane L21. In the illustrated traffic situation, the waiting vehicle VC is a visual obstacle blocking a part of a view from the right turning vehicle VA and blocking a part of a view from the straight traveling vehicle VB. In this situation, it is difficult to visually recognize the straight traveling vehicle VB from the right turning vehicle VA due to the straight traveling vehicle VB being present at a blind angle of the waiting vehicle VC seen from the right turning vehicle VA, and it is difficult to visually recognize the right turning vehicle VA from the straight traveling vehicle VB due to the right turning vehicle VA being present at a blind angle of the waiting vehicle VC seen from the straight traveling vehicle VB.

[0039] In such a situation, the notification system 1 monitors a relative positional relationship between the right turning vehicle VA and the straight traveling vehicle VB after the right turning vehicle VA displays its intention to turn right at the intersection CS (hereinafter simply referred to as a "right turn intention"). Then, the notification system 1 issues a notification in accordance with a degree of urgency of circumstances related to contact or collision between the right turning vehicle VA and the straight traveling vehicle VB at an appropriate timing after the right turning vehicle VA approaches the intersection CS and before the right turning vehicle VA passes the intersection CS.

[0040] Fig. 21 is a schematic diagram illustrating an example of a traffic situation at the virtual intersection, the traffic situation being assumed to be a notification target according to the present embodiments.

[0041] As illustrated in Fig. 21, a traffic situation where the right turning vehicle VA and the straight traveling vehicle VB face each other across a virtual intersection VCS, which is a location on the road R other than the intersection CS, will be further assumed in the present embodiment. The virtual intersection VCS is present on the road R with two lanes on each side including lanes L11, L12, L21, and L22. The right turning vehicle VA is present in the lane L11 and is approaching the virtual intersection VCS, while the straight traveling vehicle VB is present in the lane L22 and is traveling at a position separated from the virtual intersection VCS in a straight direction toward the virtual intersection VCS. It is assumed that the right turning vehicle VA turns right within the virtual intersection VCS and enters a predetermined area PA located on a roadside along the lane L22 of the road R. Here, the lane L11 corresponds to the traveling lane of the right turning vehicle VA, and the lanes L21 and L22 correspond to lanes opposite to the right turning vehicle VA. The lanes L21 and L22, which are opposite lanes, may be referred to as "opposite lanes" below. Among the traveling lanes, the lane L11 is the lane closest to the center line CL of the road R.

[0042] In addition to the right turning vehicle VA and the straight traveling vehicle VB, there is a waiting vehicle VC that is stopping to turn right to enter a predetermined area PA' located on a roadside along the lane L12 of the road R near the virtual intersection VCS in front of the straight traveling vehicle VB in the opposite lane L21. In the illustrated traffic situation, the waiting vehicle VC is a visual obstacle blocking a part of a view from the right turning vehicle VA and blocking a part of a view from the straight traveling vehicle VB. It is difficult to visually recognize the straight traveling vehicle VB from the right turning vehicle VA due to the straight traveling vehicle VB being present at a blind angle of the waiting vehicle VC seen from the right turning vehicle VA, and it is difficult to visually recognize the right turning vehicle VA from the straight traveling vehicle VB due to the right turning vehicle VA being present at a blind angle of the waiting vehicle VC seen from the straight traveling vehicle VB in this situation.

[0043] The notification system 1 monitors a relative positional relationship between the right turning vehicle VA and the straight traveling vehicle VB after the right turning vehicle VA displays its intention to turn right in the same manner as at the intersection CS, even at the virtual intersection VCS. Then, the notification system 1 issues a notification in accordance with a degree of urgency of circumstances related to contact or collision between the right turning vehicle VA and the straight traveling vehicle VB at an appropriate timing after the right turning vehicle VA approaches the virtual intersection VCS and before the right turning vehicle VA passes the virtual intersection VCS.

[0044] Note that in the present embodiment, a square section that overlaps a right turning path TRa', which is a path where the right turning vehicle VA travels when the right turning vehicle VA turns right and enters the predetermined area PA, and has a side corresponding to a road width W of the road R is assumed as the virtual intersection VCS. Furthermore, when a point where the right turning path TRa' intersects the center line CL that sections the traveling lanes L11 and L12 and the opposite lanes L21 and L22 is defined as a center position (hereinafter, referred to as a "virtual intersection center") VCTR of the virtual intersection VCS, it is assumed that the virtual intersection VCS is arranged such that the virtual intersection center VCTR is located on a virtual line segment VLS that passes through the center of the two sides of the virtual intersection VCS that are perpendicular to a road width direction of the road R.(Internal Configuration of Controller)

[0045] Fig. 2 is a schematic diagram illustrating an internal configuration of the controller 101a included in the right turning vehicle VA, and Fig. 3 is a schematic diagram illustrating an internal configuration of the controller 101b included in the straight traveling vehicle VB. The internal configuration of each of the controllers 101a and 101b will be described in turn on the basis of Figs. 2 and 3 and with reference to Figs. 11 and 12 as needed.

[0046] As illustrated in Fig. 2, the controller 101a of the right turning vehicle VA includes a host vehicle position detection unit B111a, an other vehicle position detection unit B112a, a road map storage unit B113a, a right turn intention detection unit B114a, a vehicle speed detection unit B115a, a first vehicle behavior detection unit B116a, a second vehicle behavior detection unit B117a, a first notification issuing unit B118a, a second notification issuing unit B119a, a third vehicle behavior detection unit B120a, a fourth vehicle behavior detection unit B121a, and a virtual area setting unit B122a. A function of each of these units B111a to B122a is realized in a software manner by the central processing unit included in the controller 101a reading a computer program stored in the storage device and operating in accordance with instructions of the program. In the present embodiment, the first vehicle behavior detection unit B116a and the second vehicle behavior detection unit B117a mainly function when the right turning vehicle VA turns right at the intersection CS, while the third vehicle behavior detection unit B120a, the fourth vehicle behavior detection unit B121a, and the virtual area setting unit B122a mainly function when the right turning vehicle VA turns right at the virtual intersection VCS, among the components B111a to B122a included in the controller 101a. The other components B111a to B115a, B118a, and B119a function in both a case where the right turning vehicle VA turns right at the intersection CS and a case where the right turning vehicle VA turns right at the virtual intersection VCS.

[0047] Note that data held by each of the components B111a to B122a and results of processing performed by each of the components B111a to B122a can be mutually referenced among the components B111a to B122a regardless of the presence or absence of arrows indicating a data flow inside the controller 101a in Fig. 2. The data held by each of the components B111a to B122a includes detection signals from the vehicle sensors 111a, 112a, and 113a and the steering angle sensor 114a output to the controller 101a, destination information set by the navigation device 115a, and vehicle information acquired from the straight traveling vehicle VB via the receiver 122a. These premises in the controller 101a are also applicable to the controller 101b of the straight traveling vehicle VB.

[0048] The host vehicle position detection unit B111a detects the current position Pa of the right turning vehicle VA, which is a host vehicle. The detection of the current position Pa performed by the host vehicle position detection unit B111a is based on an output signal from the position sensor 111a included in the right turning vehicle VA.

[0049] The other vehicle position detection unit B112a detects the current position Pb of the straight traveling vehicle VB, which is another vehicle. The detection of the current positions Pb performed by the other vehicle position detection unit B112a is performed by reading position information indicating the current position Pb from vehicle information acquired from the straight traveling vehicle VB via the receiver 122a included in the right turning vehicle VA.

[0050] The road map storage unit B113a stores a road map. In the present embodiment, the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB are coordinates of latitudes and longitudes indicating these positions Pa and Pb. The road map storage unit B113a extracts a map of a range or a section including the intersection CS in the road map and specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map. The map in the range or the section including the intersection CS extracted by the road map storage unit B113a is used when the right turning vehicle VA turns right at the intersection CS. The road map storage unit B113a extracts a map in a specific range or a specific section in the road map and specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map. The map in the specific range or the specific section extracted by the road map storage unit B113a is used when the right turning vehicle VA turns right at the virtual intersection VCS. The map in the specific range or the specific section may include the intersection CS or may not include the intersection CS. In the road map, identifiers (hereinafter, referred to as "link IDs") corresponding to lanes leading to at least one of the intersection CS and the virtual intersection VCS, such as the lanes L11, L21, L12, and L22, are assigned and are stored so as to correspond to the lanes L11, L21, L12, and L22. It is possible to distinguish the lane in which a target vehicle is present or is traveling by specifying the position thereof on the road map.

[0051] The road map includes, for example, position information of roadside buildings RB that include stores, facilities, and residences located on the roadsides along the road R. In the present embodiment, a roadside building RB that has a site where the right turning vehicle VA enters by turning right at the virtual intersection VCS among the roadside buildings RB may be referred to as the predetermined area PA including the site. Furthermore, the road map includes, for example, position information of a median strip provided to separate the traveling lanes L11 and L12 from the opposite lanes L21 and L22. Therefore, the map in the range or the section including the intersection CS or the map in the specific range or the specific section extracted by the road map storage unit B113a may include the position information of the roadside building RB and / or the median strip.

[0052] The right turn intention detection unit B114a detects that the right turning vehicle VA has a right turn intention. The right turn intention detection by the right turn intention detection unit B114a can be performed with an output signal from the right turn signal switch 113a included in the right turning vehicle VA, and in a case where the right turn lane L11 near the intersection CS is a lane only for right turn, the detection can also be performed by reading the link ID associated with the lane where the vehicle is traveling from the road map and detecting that the right turning vehicle VA is present in the right turn lane L11.

[0053] The vehicle speed detection unit B115a detects the vehicle speed VSPb of the straight traveling vehicle VB. The vehicle speed detection unit B115a detects the vehicle speed VSPb of the straight traveling vehicle VB (that is, another vehicle) by reading vehicle speed information indicating the vehicle speed VSPb from the vehicle information acquired from the straight traveling vehicle VB via the receiver 122a included in the right turning vehicle VA.

[0054] The first vehicle behavior detection unit B116a detects that the right turning vehicle VA is present at a first predetermined position P1 in the lane (that is, the right turn lane L11) where the right turning vehicle VA is traveling or at a position closer to a center position (hereinafter, referred to as an "intersection center") CTR of the intersection CS than the first predetermined position P1 after the right turn intention detection unit B114a detects the right turn intention on the basis of the current position Pa of the right turning vehicle VA on the road map, in other words, after the right turning vehicle VA displays its right turn intention by entering the right turn lane L11 or operating the right turn signal.

[0055] Fig. 12 is a schematic diagram illustrating a positional relationship between the right turning vehicle VA and the straight traveling vehicle VB at a timing when the right turning vehicle VA exceeds the stop line SL1 in the right turn lane L11 and enters the intersection CS. Fig. 12 illustrates only the right turn lane L11 and the straight lane L22 in the road R with two lanes on each side by simplifying the illustration of the road R (the same applies to Figs. 13 and 14, which will be described later).

[0056] In the present embodiment, an intersection area ACS is set as a determination criterion to recognize a relative positional relationship between the right turning vehicle VA and the intersection CS in a case where the right turning vehicle VA turns right at the intersection CS. The intersection area ACS is set to overlap a path TRa along which the right turning vehicle VA travels when passing the intersection CS, and the presence of the right turning vehicle VA at the first predetermined position P1 in the right turn lane L11 or the position closer to the intersection center CTR than the first predetermined position P1 is detected by arrival of the right turning vehicle VA at the intersection area ACS or entrance thereof into the intersection area ACS after displaying its right turn intention. The first vehicle behavior detection unit B116a sets the timing at which the right turning vehicle VA reaches the intersection area ACS or enters the intersection area ACS as a first notification issuance timing. The first notification issuance timing set by the first vehicle behavior detection unit B116a is a timing at which notification issuance in a first predetermined mode is performed in the right turning vehicle VA. The intersection area ACS is set as a circular area that includes the first predetermined position P1 on its outer edge concentrically with the intersection center CTR. Figs. 12 to 14 illustrate the intersection area ACS by two-dotted chain lines, illustrate the traveling path TRa of the right turning vehicle VA by one-dotted chain lines, and illustrate a predicted collision area ACP and a traveling path TRb of the straight traveling vehicle VB, which will be described later, by dashed lines and one-dotted chain lines, respectively.

[0057] The second vehicle behavior detection unit B117a regards, as a "predicted collision point" CPP, a point at which the path TRa along which the right turning vehicle VA travels when passing the intersection CS and the path TRb along which the straight traveling vehicle VB travels when passing the intersection CS intersect and detects, on the basis of the current position Pa of the right turning vehicle VA on the road map, that the right turning vehicle VA is traveling at a position closer to the predicted collision point CPP than the first predetermined position P1 toward the predicted collision point CPP or that the right turning vehicle VA is present at a position closer to the predicted collision point CPP than a second predetermined position P2 between the first predetermined position P1 and the predicted collision point CPP.

[0058] Fig. 13 is a schematic diagram illustrating a positional relationship between the right turning vehicle VA and the straight traveling vehicle VB at a timing at which the right turning vehicle VA moves ahead inside the intersection CS and approaches the intersection center CTR after entering the intersection CS.

[0059] In the present embodiment, the predicted collision area ACP with the predicted collision point CPP included at its center is set as an area that is different from the intersection area ACS. The traveling of the right turning vehicle VA at a position closer to the predicted collision point CPP than the first predetermined position P1 or presence of the right turning vehicle VA at a position closer to the predicted collision point CPP than the second predetermined position P2 is detected on the basis of the right turning vehicle VA traveling toward the predicted collision point CPP inside the intersection area ACS or being present inside the predicted collision area ACP after entering the intersection area ACS. The second vehicle behavior detection unit B117a sets the timing at which traveling of the right turning vehicle VA toward the predicted collision point CPP inside the intersection area ACS or presence of the right turning vehicle VA inside the predicted collision area ACP is detected as a second notification issuance timing. The second notification issuance timing set by the second vehicle behavior detection unit B117a is a timing at which the right turning vehicle VA performs notification issuance in a second predetermined mode. The predicted collision area ACP is set as a circular area that includes the second predetermined position P2 on its outer edge and has a smaller area than the intersection area ACS.

[0060] The shape of the intersection area ACS is not limited to the circular shape and may be a shape (for example, a quadrangular shape having four corners at a corner cut) following a range in which the two intersecting roads overlap or may be a shape within a range surrounded by the stop lines SL1 and SL2 provided in the intersecting roads, respectively. The same applies to the predicted collision area ACP, and it is possible to set a shape other than the circular shape, such as a quadrangular shape (for example, a quadrangular shape having two sides that are parallel to a road boundary line defining the opposite straight lane L22).

[0061] The first notification issuing unit B118a outputs a command signal to perform notification issuance in the first predetermined mode to the HMI device 131a included in the host vehicle (that is, the right turning vehicle VA) under a condition that a first predetermined notification issuance condition defined in advance in regard to the position Pb of another vehicle, which is the straight traveling vehicle VB, is met at the timing at which the presence of the right turning vehicle VA at the first predetermined position P1 in the right turn lane L11 or a position closer to the intersection center CTR than the first predetermined position P1 is detected, that is, at the first notification issuance timing. In the present embodiment, the output of the command signal to perform the notification issuance in the first predetermined mode from the first notification issuing unit B118a to the HMI device 131a is regarded as "execution of the notification issuance in the first predetermined mode".

[0062] The first predetermined notification issuance condition is that the straight traveling vehicle VB is present at a first predetermined distance (hereinafter, referred to as an "information presentation distance") Dth1, which is relatively long, from the intersection CS or at a position closer to the intersection CS than the first predetermined distance Dth1. In the present embodiment, the distance from the outer edge of the predicted collision area ACP, specifically, an intersecting point between the traveling path TRb of the straight traveling vehicle VB and the circle (the circle illustrated by the dashed line in the drawings) defining the outer edge of the predicted collision area ACP to the straight traveling vehicle VB as illustrated in Figs. 12 and 13 is employed as a distance Db from the intersection CS to the straight traveling vehicle VB.

[0063] The HMI device 131a that has received the command signal from the first notification issuing unit B118a to perform the notification issuance in the first predetermined mode issues a notification to promote the driver of the right turning vehicle VA to recognize that the straight traveling vehicle VB traveling toward the intersection CS in the opposite straight lane L22 is present using display and sound. The notification issuance performed by the first notification issuing unit B118a is notification issuance to present information for relatively low urgency in regard to collision between the right turning vehicle VA and the straight traveling vehicle VB.

[0064] The second notification issuing unit B119a outputs a command signal to issue a notification in a second predetermined mode to the HMI device 131a under a condition that a second predetermined notification issuance condition defined in advance in regard to the position Pb of the straight traveling vehicle VB is established at a timing at which traveling of the right turning vehicle VA at a position closer to the predicted collision point CPP than the first predetermined position P1 or presence of the right turning vehicle VB at a position closer to the predicted collision point CPP than the second predetermined position P2 is detected, that is, at the first notification issuance timing. In the present embodiment, the output of the command signal to perform the notification issuance in the second predetermined mode from the second notification issuing unit B119a to the HMI device 131a is regarded as "execution of the notification issuance in the second predetermined mode".

[0065] The second predetermined notification issuance condition is that the straight traveling vehicle VB is present at a second predetermined distance (hereinafter, referred to as an "alarm distance") Dth2, which is shorter than the information presentation distance Dth1, from the intersection CS or at a position closer to the intersection CS than the second predetermined distance Dth2.

[0066] The notification issuance in the second predetermined mode is notification issuance in a mode that is different from the first predetermined mode, and the HMI device 131a that has received the command signal from the second notification issuing unit B119a to perform the notification issuance in the second predetermined mode issues a notification to promote the driver of the right turning vehicle VA to recognize higher urgency in regard to collision between the right turning vehicle VA and the straight traveling vehicle VB using display and sound. The notification issuance performed by the second notification issuing unit B119a is notification issuance that is more prominent and more visually or auditorily appealing to the driver as compared with the notification issuance performed by the first notification issuing unit B118a.

[0067] The first notification issuing unit B118a and the second notification issuing unit B119a can also provide a notification that the notification issuance in each mode (the notification issuance in the first predetermined mode and the notification issuance in the second predetermined mode) has been performed to the straight traveling vehicle VB via the transmitter 121a together with the output of the command signal to the HMI device 131a and promote the straight traveling vehicle VB to perform notification issuance in an appropriate mode in accordance with a degree of urgency in regard to collision against the host vehicle (that is, the right turning vehicle VA).

[0068] Fig. 10 is an explanatory diagram illustrating a method of calculating the information presentation distance Dth1 and the alarm distance Dth2.

[0069] The information presentation distance Dth1 and the alarm distance Dth2 are calculated as a distance by which the straight traveling vehicle VB is expected to travel before stopping after the notification issuance, that is, the distance required by the straight traveling vehicle VB to stop on the basis of the vehicle speed VSPb of the straight traveling vehicle VB and deceleration degrees DEC1 and DEC2 set in advance in accordance with the modes of the notification issuance. Hereinafter, the deceleration degree DEC1 may be referred to as a "first predetermined deceleration degree DEC1". The deceleration degree DEC2 may be referred to as a "second predetermined deceleration degree DEC2".

[0070] Specifically, the information presentation distance Dth1 is calculated by adding the distances for which the straight traveling vehicle VB is expected to travel for a break reaction time PRD1 and a deceleration time PRD2 on the basis of the vehicle speed VSPb (= V1) of the straight traveling vehicle VB at the detection timing of the first vehicle behavior detection unit B116a. The break reaction time PRD1 is a total time of a reaction time required for perception, judgment, and operation before the driver actually performs a brake operation after the notification issuance and an operation delay time for the system, hydraulic equipment, and the like in response to the brake operation. In the present embodiment, the break reaction time PRD1 is set in advance as a constant time (= ΔT). The deceleration time PRD2 is a time required for the vehicle to come to a stop after the brake actually starts to work and can be calculated on the basis of the vehicle speed VSPb and the deceleration degree DEC1 (PRD2 = V1 / DEC1). In this manner, the calculation of the information presentation distance Dth1 is given by Equation (1) below. Dth 1 = V 1 × ΔT + V 1 × V 1 / DEC 1 / 2

[0071] Although the alarm distance Dth2 is similarly calculated by adding the distance for which the straight traveling vehicle VB is expected to travel for each of the break reaction time PRD1 and the deceleration time PRD2, the deceleration degree DEC2 which is different from that used to calculate the information presentation distance Dth1 is employed. The deceleration degree DEC2 for calculating the alarm distance is a higher deceleration degree than the deceleration degree DEC1 for calculating the information presentation distance, in other words, a deceleration degree having a larger absolute value than that of the deceleration degree DEC1 (|DEC1| < |DEC2|). Specifically, it is given by Equation (2) below. Dth 2 = V 1 × ΔT + V 1 × V 1 / DEC 2 / 2

[0072] Fig. 22 is a schematic diagram illustrating a positional relationship between the right turning vehicle VA and the straight traveling vehicle VB at a timing when the right turning vehicle VA enters the virtual intersection VCS. Fig. 22 illustrates only the right turn lane L11 and the straight lane L22 in the road R with two lanes on each side by simplifying the illustration of the road R. Similarly, the illustration of the road R in each of Figs. 23 to 26, which will be described later, is also simplified.

[0073] In the present embodiment, a virtual intersection area VACS is set under a condition that a predetermined setting condition is met in a case where the right turning vehicle VA turns right at the virtual intersection VCS. The virtual intersection area VACS is used as a determination criterion for recognizing a relative positional relationship between the right turning vehicle VA and the virtual intersection VCS. Additionally, the virtual intersection area VACS serves as a trigger for the notification system 1 to specify the right turning vehicle VA turning right at the virtual intersection VCS as a vehicle to which attention is to be paid. The setting of the virtual intersection area VACS is performed by the virtual area setting unit B122a. The virtual intersection area VACS is set to encompass the virtual intersection center VCTR in a case where a point at which a right turning path TRa' that is a path where the right turning vehicle VA travels when the right turning vehicle VA passes the virtual intersection VCS, that is, when the right turning vehicle VA crosses the opposite lane L22 and turns right to enter the predetermined area PA located on the roadside along the opposite lane L22 and the center line CL that sections the traveling lane L11 and the opposite lane L22 intersect as the virtual intersection center VCTR. In other words, the virtual intersection area VACS is set to overlap with the right turning path TRa'. Presence of the right turning vehicle VA at a predetermined position relative to the virtual intersection VCS is detected on the basis of the right turning vehicle VA reaching the virtual intersection area VACS or entering the virtual intersection area VACS. The virtual intersection area VACS may be set as a circular area with a predetermined radius centered at the virtual intersection center VCTR, for example. Figs. 22 to 24 illustrate the virtual intersection area VACS by two-dotted chain lines, illustrate the right turning path TRa' of the right turning vehicle VA by one-dotted chain lines, and illustrate a virtual predicted collision area VACP and a traveling path TRb' of the straight traveling vehicle VB, which will be described later, by dashed lines and one-dotted chain lines, respectively.

[0074] Fig. 23 is a schematic diagram illustrating a positional relationship between the right turning vehicle VA and the straight traveling vehicle VB at a timing at which the right turning vehicle VA moves ahead inside the virtual intersection VCS and approaches the virtual intersection center VCTR after entering the virtual intersection VCS.

[0075] In the present embodiment, the virtual predicted collision area VACP is set as an area that is different from the virtual intersection area VACS under a condition that the same predetermined setting condition as that for setting the virtual intersection area VACS is met in a case where the right turning vehicle VA turns right at the virtual intersection VCS. The setting of the virtual predicted collision area VACP is performed by the virtual area setting unit B122a similarly to the virtual intersection area VACS. The virtual predicted collision area VACP is set to encompass a virtual predicted collision point VCPP in a case where the point at which the right turning path TRa' of the right turning vehicle VA and the straight traveling path TRb' that is a path where the straight traveling vehicle VB travels intersect as the virtual predicted collision point VCPP. In other words, the virtual predicted collision area VACP is set to overlap with the right turning path TRa'. Traveling of the right turning vehicle VA toward the virtual predicted collision point VCPP inside the virtual intersection area VACS or presence of the right turning vehicle VA inside the virtual predicted collision area VACP is detected after the right turning vehicle VA enters the virtual intersection area VACS. The virtual predicted collision area VACP is set as a circular area with a predetermined radius and a smaller area than the virtual intersection area VACS. Note that the straight traveling path TRb' of the straight traveling vehicle VB can be replaced with a virtual straight line that passes the center of the lane L22 where the straight traveling vehicle VB is present and is parallel to the center line CL.

[0076] The shape of the virtual intersection area VACS is not limited to the circular shape around the virtual intersection center VCTR, and the virtual intersection area VACS may be, for example, the virtual intersection VCS itself. The same applies to the virtual predicted collision area VACP, and it is possible to set a quadrangular shape that has two sides parallel to the road boundary line that defines the opposite lane L22 for straight traveling vehicles, for example, or a shape other than the circular shape.

[0077] The third vehicle behavior detection unit B120a detects that the right turning vehicle VA is present at a predetermined position relative to the virtual intersection VCS, specifically that the right turning vehicle VA is at a predetermined distance from the virtual intersection center VCTR, which is a center position of the virtual intersection VCS, or has approached the virtual intersection center VCTR than the predetermined distance, on the basis of the current position Pa of the right turning vehicle VA on the road map. In other words, the third vehicle behavior detection unit B120a detects that the right turning vehicle VA has reached the virtual intersection area VACS or has entered the virtual intersection area VACS. Then, the third vehicle behavior detection unit B120a sets a timing at which any of these behaviors of the right turning vehicle VA is detected as a third notification issuance timing. The third notification issuance timing set by the third vehicle behavior detection unit B120a is a timing at which the right turning vehicle VA performs notification issuance in the third predetermined mode.

[0078] The first notification issuing unit B118a outputs a command signal to perform the notification issuance in the third predetermined mode to the HMI device 131a included in the host vehicle (that is, the right turning vehicle VA) under the condition that a third predetermined notification issuance condition defined in advance in regard to the position Pb of another vehicle, which is the straight traveling vehicle VB, is met at the third notification issuance timing set by the third vehicle behavior detection unit B120a. In the present embodiment, content of the notification issuance in the third predetermined mode is the same as the content of the notification issuance in the first predetermined mode. The content of the notification issuance in the third predetermined mode is not limited thereto and may be different from the content of the notification issuance in the first predetermined mode.

[0079] The third predetermined notification issuance condition is that the straight traveling vehicle VB is present at a third predetermined distance (hereinafter, referred to as an "information presentation distance") Dth3, which is relatively long, from the virtual intersection VCS or at a position closer to the virtual intersection VCS than the third predetermined distance Dth3. In the present embodiment, the distance from the outer edge of the virtula predicted collision area VACP, specifically, an intersecting point between the traveling path TRb' of the straight traveling vehicle VB and the circle (the circle illustrated by the dashed line in the drawings) defining the outer edge of the virtual predicted collision area VACP to the straight traveling vehicle VB as illustrated in Figs. 22 and 23 is employed as a distance Db' from the virtual intersection VCS to the straight traveling vehicle VB.

[0080] In the present embodiment, the information presentation distance Dth3 can be calculated in the same manner as the information presentation distance Dth1. The information presentation distance Dth3 is calculated by adding the distances for which the straight traveling vehicle VB is expected to travel for the break reaction time PRD1 and the deceleration time PRD2 on the basis of the vehicle speed VSPb (= V1') of the straight traveling vehicle VB at the third notification issuance timing set by the third vehicle behavior detection unit B120a. When a deceleration degree for calculating the information presentation distance is set in advance as a third predetermined deceleration degree DEC3 according to the notification issuance in the third predetermined mode, the calculation of the information presentation distance Dth3 is given by Equation (3) below. Dth 3 = V 1 ′ × ΔT + V 1 ′ × V 1 ′ / DEC 3 / 2

[0081] Note that in the present embodiment, the third predetermined deceleration degree DEC3 is the same deceleration degree as the first predetermined deceleration degree DEC1. However, the third predetermined deceleration degree DEC3 is not limited thereto and may be a deceleration degree different from the first predetermined deceleration degree DEC1.

[0082] The fourth vehicle behavior detection unit B121a monitors a behavior of the right turning vehicle VA after the setting of the third notification issuance timing. In other words, the fourth vehicle behavior detection unit B121a monitors a behavior of the right turning vehicle VA after entering the virtual intersection area VACS. The fourth vehicle behavior detection unit B121a detects whether the right turning vehicle VA is traveling toward the virtual predicted collision point VCPP inside the virtual intersection area VACS or is present inside the virtual predicted collision area VACP on the basis of the current position Pa of the right turning vehicle VA on the road map. Then, the fourth vehicle behavior detection unit B121a sets the timing at which any of these behaviors of the right turning vehicle VA is detected as a fourth notification issuance timing. The fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a is a timing at which the right turning vehicle VA performs notification issuance in the fourth predetermined mode.

[0083] The second notification issuing unit B119a outputs a command signal to issue a notification in a fourth predetermined mode to the HMI device 131a under a condition that a fourth predetermined notification issuance condition defined in advance in regard to the position Pb of the straight traveling vehicle VB is established at the fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a. In the present embodiment, content of the notification issuance in the fourth predetermined mode is the same as the content of the notification issuance in the second predetermined mode. The content of the notification issuance in the fourth predetermined mode is not limited thereto and may be different from the content of the notification issuance in the second predetermined mode.

[0084] The fourth predetermined notification issuance condition is that the straight traveling vehicle VB is present at a fourth predetermined distance (hereinafter, referred to as an "alarm distance") Dth4, which is shorter than the information presentation distance Dth3, from the virtual intersection VCS or at a position closer to the virtual intersection VCS than the fourth predetermined distance Dth4.

[0085] In the present embodiment, the alarm distance Dth4 can be calculated in the same manner as the alarm distance Dth2. The alarm distance Dth4 is calculated by adding the distances for which the straight traveling vehicle VB is expected to travel for the break reaction time PRD1 and the deceleration time PRD2 on the basis of the vehicle speed VSPb (= V1') of the straight traveling vehicle VB at the fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a. When a deceleration degree for calculating the alarm distance is larger than the third predetermined deceleration DEC3 and is set in advance as a fourth predetermined deceleration degree DEC4 according to the notification issuance in the fourth predetermined mode, the calculation of the alarm distance Dth4 is given by Equation (4) below. Dth 4 = V 1 ′ × ΔT + V 1 ′ × V 1 ′ / DEC 4 / 2

[0086] However, the absolute value of the fourth predetermined deceleration degree DEC4 is greater than that of the third predetermined deceleration degree DEC3.

[0087] Note that in the present embodiment, the third predetermined deceleration degree DEC3 is the same deceleration degree as the first predetermined deceleration degree DEC1. However, the third predetermined deceleration degree DEC3 is not limited thereto and may be a deceleration degree different from the first predetermined deceleration degree DEC1.

[0088] The notification issuance in the second predetermined mode is notification issuance in a mode that is different from the third predetermined mode, and the HMI device 131a that has received the command signal from the second notification issuing unit B119a to perform the notification issuance in the fourth predetermined mode issues a notification to promote the driver of the right turning vehicle VA to recognize higher urgency in regard to collision between the right turning vehicle VA and the straight traveling vehicle VB using display and sound.

[0089] The first notification issuing unit B118a and the second notification issuing unit B119a can also provide a notification that the notification issuance in each mode (the notification issuance in the third predetermined mode and the notification issuance in the fourth predetermined mode) has been performed to the straight traveling vehicle VB via the transmitter 121a together with the output of the command signal to the HMI device 131a and promote the straight traveling vehicle VB to perform notification issuance in an appropriate mode in accordance with a degree of urgency in regard to collision against the host vehicle (that is, the right turning vehicle VA).

[0090] The virtual area setting unit B122a regards the fact that the right turning vehicle VA is present in the traveling lane L11 while the straight traveling vehicle VB is present in the opposite lane L22 and the right turn intention detection unit B114a has detected the right turn intention of the right turning vehicle VA as a predetermined setting condition and sets the virtual intersection area VACS and the virtual predicted collision area VACP in an associated manner on the road map in a case where the predetermined setting condition is met. In the present embodiment, the virtual area setting unit B122a sets the virtual intersection area VACS and the virtual predicted collision area VACP on the map in the specific range or the specific section extracted by the road map storage unit B113a. Thus, the third vehicle behavior detection unit B120a can set the third notification issuance timing, and the fourth vehicle behavior detection unit B121a can set the fourth notification issuance timing. Furthermore, the first notification issuing unit B118a can perform the notification issuance in the third predetermined mode with an intention to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA, and the second notification issuing unit B119a can perform notification issuance in the fourth predetermined mode with an intention to provide an alarm to promote recognition of high urgency in regard to the collision between the straight traveling vehicle VB and the right turning vehicle VA. Therefore, even in a case where the right turning path TRa' of the right turning vehicle VA and the straight traveling path TRb' of the straight traveling vehicle VB intersect at a location other than the intersection CS of the road R, it is possible to provide a notification that assists in avoiding collision between the right turning vehicle VA and the straight traveling vehicle VB. In other words, it is possible to perform notification issuance in an appropriate mode at an appropriate timing in accordance with a degree of urgency of a situation where there is a concern that the right turning vehicle VA and the straight traveling vehicle VB may collide against each other at a location other than the intersection CS of the road R.

[0091] Fig. 25 is a schematic diagram illustrating the right turning path TRa' of the right turning vehicle VA set by the virtual area setting unit B122a.

[0092] Here, the right turning path TRa' set by the virtual area setting unit B122a will be described with reference to Fig. 25. The right turning path TRa' is used when the virtual area setting unit B122a sets the virtual intersection center VCTR, the virtual intersection VCS, the virtual predicted collision point VCPP, the virtual intersection area VACS, and the virtual predicted collision area VACP in an associated manner on the road map as illustrated in Figs. 22 to 24. The right turning path TRa' is set as follows, for example.

[0093] First, the virtual area setting unit B122a detects a roadside building RB located on the roadside along the opposite lane L22 of the road R, which is the closest to a point Ps on the road R separated from the right turning vehicle VA on the front side by a specific distance Dpa, as a predetermined area PA from among a plurality of roadside buildings RB in the map in the specific range or the specific section extracted by the road map storage unit B113a at the timing at which the right turn intention of the right turning vehicle VA is detected. The point Ps is a point where it is predicted that the right turning vehicle VA will start to turn right. In other words, the distance Dpa is the distance from the position of the right turning vehicle VA at the timing at which its intention to turn right is detected to the point where it is predicted that the right turning vehicle VA will start to turn right. The specific distance is, for example, 30 meters (m).

[0094] Next, the virtual area setting unit B122a sets a traveling path serving as a norm when the right turning vehicle VA turns right and enters the predetermined area PA as the right turning path TRa' on the map using the detected predetermined area PA as a base point, more specifically, using the representative position of the predetermined area PA as a base point. In a case where the road map has the position information regarding an entrance of the predetermined area PA, the representative position of the predetermined area PA may also be the position of the entrance of the predetermined area PA. The entrance of the predetermined area PA is provided to be continuous with the opposite lane L22.

[0095] Note that he virtual area setting unit B122a can set the right turning path TRa' even if the predetermined setting condition for setting the virtual intersection area VACS and the virtual predicted collision area VACP has not been met as long as the right turn intention of the right turning vehicle VA has been detected. In other words, the virtual area setting unit B122a can set the right turning path TRa' even in a situation where the straight traveling vehicle VB is not present in the lane L22. Moreover, the virtual area setting unit B122a does not set the right turning path TRa' in a case where a continuous median strip is present at a position where the right turning path TRa' is to be set on the map and the right turning vehicle VA cannot turn right. Additionally, the notification system 1 may include an in-vehicle camera (not illustrated) that images the front of the vehicle, for example. Furthermore, the virtual area setting unit B122a may be configured not to set the right turning path TRa' in a case where the median strip or a road sign prohibiting crossing across the opposite lane L22 is detected from an image captured by the in-vehicle camera.

[0096] Also, the first notification issuing unit B118a may not output the command signal to perform the notification issuance in the third predetermined mode, and the second notification issuing unit B119a may not output the command signal to perform the notification issuance in the fourth predetermined mode in a case where the right turning vehicle VA is present in the traveling lane L11 leading to the intersection CS in order to turn right at the intersection CS of the road R and the right turning vehicle VA has entered the intersection area ACS that overlaps the path where the right turning vehicle VA travels when the right turning vehicle VA passes the intersection CS and that is set in advance in association with the road map. Thus, the first notification issuing unit B118a prioritizes the output of the command signal to perform the notification issuance in the first predetermined mode to the HMI device 131a and the execution of the notification issuance in the first predetermined mode over the command signal to perform the notification issuance in the third predetermined mode. Furthermore, the second notification issuing unit B119a prioritizes the output of the command signal to perform the notification issuance in the second predetermined mode to the HMI device 131a and execution of the notification issuance in the second predetermined mode over the command signal to perform the notification issuance in the fourth predetermined mode. In other words, the notification system 1 uses the intersection area ACS and the predicted collision area ACP as a condition to set the predetermined notification issuance timing and a condition to perform the notification issuance in the predetermined mode in a case where the right turning vehicle VA turns right at the intersection CS, the position of which on the map is set in advance, and uses the virtual intersection area VACS and the virtual predicted collision area VACP as a condition to set the predetermined notification issuance timing and a condition to perform the notification issuance in the predetermined mode in a case where the right turning vehicle VA turns right at the virtual intersection VCS. Thus, the notification system 1 can distinguish the case of turning right at the intersection CS and the case of turning right at a location other than the intersection CS, that is, turning right at the virtual intersection VCS and can perform the notification issuance in an appropriate predetermined mode when the right turning vehicle VA passes the intersection CS in a case where the right turning vehicle VA actually passes the intersection CS even after the setting of the virtual intersection area VACS and the virtual predicted collision area VACP.

[0097] Moreover, the virtual area setting unit B122a may not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB exceeds a fifth predetermined distance (hereinafter, a predetermined separation distance) Dth5 that is relatively long. A risk of collision against the straight traveling vehicle VB is low even if the right turning vehicle VA turns right and crosses the opposite lane L22 in a case where the right turning vehicle VA and the straight traveling vehicle VB are present at a sufficiently long distance exceeding the predetermined separation distance Dth5. Therefore, the virtual area setting unit B122a does not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance between the right turning vehicle VA and the straight traveling vehicle VB exceeds the predetermined separation distance Dth5 even if the aforementioned predetermined setting condition has been met. A calculation load is thus reduced as compared with a case where the unnecessary virtual intersection area VACS and virtual predicted collision area VACP are set. On the other hand, the virtual area setting unit B122a can execute the notification in the predetermined mode with an appropriate positional relationship between the right turning vehicle VA and the straight traveling vehicle VB by setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance between the right turning vehicle VA and the straight traveling vehicle VB is equal to or less than the predetermined separation distance Dth5.

[0098] Note that the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB can be obtained from the current position Pa of the right turning vehicle VA and the current position Pb of the straight traveling vehicle VB as coordinate information on the road map. Moreover, the predetermined separation distance Dth5 is, for example, a distance that is sufficiently longer than the information presentation distance Dth3.

[0099] Additionally, the virtual area setting unit B122a may not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where a predetermined vehicle speed VSP1, which will be described later, is defined as a first predetermined vehicle speed VSP1 and the vehicle speed VSPa of the right turning vehicle VA exceeds a second predetermined vehicle speed VSP2 that is a vehicle speed higher than the first predetermined vehicle speed VSP1. In general, vehicles reduce their vehicle speeds to make a right turn. In other words, vehicles are likely not to turn right in a case where the vehicle speeds are not reduced. Therefore, the virtual area setting unit B122a determines that the right turning vehicle VA will not turn right and does not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the vehicle speed VSPa of the right turning vehicle VA exceeds the second predetermined vehicle speed VSP2 even in a case where the aforementioned predetermined setting condition has been met. A calculation load is thus reduced as compared with a case where the virtual intersection area VACS and the virtual predicted collision are VACP, which are not necessary because the right turning vehicle VA does not turn right, are set. On the other hand, the virtual area setting unit B122a can execute the notification in a predetermined mode with an appropriate positional relationship between the right turning vehicle VA and the straight traveling vehicle VB by setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the second predetermined vehicle speed VSP2. Note that the second predetermined vehicle speed VSP2 is, for example, 50 km / h.

[0100] Additionally, the virtual intersection area VACS may include four vertices of the virtual intersection VCS on its outer edge. In other words, the virtual area setting unit B122a may set the virtual intersection area VACS with an outer edge that includes the four vertices of the virtual intersection VCS. As described above, the virtual intersection area VACS is a square section with a side corresponding to the road width W of the road R. Therefore, the virtual area setting unit B122a sets the virtual intersection area VACS with an area size (wideness) in accordance with the location where the right turning vehicle VA turns right on the road R in the virtual intersection area VACS by setting the virtual intersection area VACS with the outer edge that includes the four vertices of the virtual intersection VCS. This allows the virtual intersection area VACS to be used more appropriately as a determination criterion for recognizing the relative positional relationship between the right turning vehicle VA and the virtual intersection VCS.

[0101] Furthermore, the virtual area setting unit B122a may set the virtual intersection area VACS such that the right turning vehicle VA is not present inside the virtual intersection area VACS and the outer edge of the virtual intersection area VACS is located just in front of the right turning vehicle VA. Thus, the right turning vehicle VA reaches the virtual intersection area VACS or enters the virtual intersection area VACS in a relatively short time after the virtual intersection area VACS is set, the third vehicle behavior detection unit B120a can set the third notification issuance timing, and the fourth vehicle behavior detection unit B121a can then set the fourth notification issuance timing. In other words, the notification issuance in the third predetermined mode with an intention to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA and the notification issuance in the fourth predetermined mode with an intention to provide an alarm to promote recognition of high urgency are more reliably performed. Note that the virtual area setting unit B122a may set the virtual intersection area VACS such that a part of a front portion of the right turning vehicle VA is present inside the virtual intersection area VACS.

[0102] Additionally, the virtual area setting unit B122a may set the right turning path TRa' in an associated manner on the road map on the basis of destination information of the navigation device 115a in which the predetermined area PA is set as a destination or at least one of the vehicle speed VSPa of the right turning vehicle VA and a steering amount of the right turning vehicle VA detected by the steering angle sensor 114a, which is a steering amount detection section.

[0103] Specifically, the virtual area setting unit B122a detects the predetermined area PA from the map in the specific range or the specific section extracted by the road map storage unit B113a on the basis of the destination information of the navigation device 115a in a case where a right turn intention of the right turning vehicle VA is detected. Then, the virtual area setting unit B122a sets the traveling path, which serves as a norm when the right turning vehicle VA turns right and enters the predetermined area PA, as the right turning path TRa' on the map using the detected predetermined area PA as a base point. The virtual area setting unit B122a can thus accurately set the right turning path TRa' while reducing the calculation load as compared with processing for specifying the predetermined area PA using the specific distance Dpa, which is the distance from the position of the right turning vehicle VA at the timing at which the right turn intention of the right turning vehicle VA is detected to the point where it is predicted that the right turning vehicle VA will start to turn right. In other words, the virtual area setting unit B122a improves setting accuracy of the virtual intersection area VACS and the virtual predicted collision area VACP on the basis of the accurately set right turning path TRa'. It is thus possible to accurately perform the notification issuance in a predetermined mode based on the virtual intersection area VACS and the virtual predicted collision area VACP.

[0104] Furthermore, the virtual area setting unit B122a determines that the right turning vehicle VA will turn right and enter another predetermined area PA that is present at a position closer to the right turning vehicle VA than the predetermined area PA detected from the map at the timing at which the right turn intention of the right turning vehicle VA is detected in a case where the steering angle of the right turning vehicle VA detected by the steering angle sensor 114a has significantly changed rightward, and / or the vehicle speed VSPa of the right turning vehicle VA detected by the vehicle speed sensor 112a has significantly dropped after the detection of the right turn intention of the right turning vehicle VA. In other words, the virtual area setting unit B122a determines such behavior changes of the right turning vehicle VA as signs of a right turn. Then, the virtual area setting unit B122a performs correction to shorten the specific distance Dpa as a change in steering angle in the right rotation direction of the right turning vehicle VA is greater and / or as the decrease in vehicle speed VSPa of the right turning vehicle VA is greater, detects the predetermined area PA again on the basis of the specific distance Dpa after the correction, and resets the right turning path TRa'. An error between the right turning path TRa' and the traveling path when the right turning vehicle VA actually turns right thus decreases, and the virtual area setting unit B122a improves setting accuracy of the virtual intersection area VACS and the virtual predicted collision area VACP set on the basis of the right turning path TRa'. In other words, it is possible to accurately perform the notification issuance in a predetermined mode based on the virtual intersection area VACS and the virtual predicted collision area VACP.

[0105] Fig. 26 is a schematic diagram illustrating virtual intersection area candidates VACSC and virtual predicted collision area candidates VACPC generated by the virtual area setting unit B122a.

[0106] As illustrated in Fig. 26, the virtual area setting unit B122a may determine the virtual intersection area VACS from among at least one virtual intersection area candidate VACSC, which is a candidate for the virtual intersection area VACS, and determine the virtual predicted collision area VACP from among at least one virtual predicted collision area candidate VACPC, which is a candidate for the virtual predicted collision area VACP, by determining the predetermined area PA from at least one predetermined area candidate PAC, which is a candidate for the predetermined area PA, when the virtual intersection area VACS and the virtual predicted collision area VACP are set. In this case, the virtual area setting unit B122a specifically performs the following series of processing. Note that the virtual area setting unit B122a may constantly perform the following series of processing when the right turning vehicle VA is present in the traveling lane.

[0107] First, the virtual area setting unit B122a detects at least one roadside building RB that is located in the traveling direction of the right turning vehicle VA, that is, on the front side and is located on the roadside along the opposite lane L22 of the road R from the road map on the basis of the current position Pa of the right turning vehicle VA specified on the road map. The virtual area setting unit B122a sets at least one detected roadside building RB as a candidate for the predetermined area PA which the right turning vehicle VA may turn right and enter in the future, that is, predetermined area candidate PAC. Note that the number of predetermined area candidates PAC is not particularly limited.

[0108] Next, the virtual area setting unit B122a sets a normative path where the right turning vehicle VA will travel to turn right and enter each of at least one predetermined area candidate PAC set as a right turning path candidate TRa'C, which is a candidate for the right turning path TRA', in an associated manner on the road map.

[0109] Next, the virtual area setting unit B122a sets a point at which the at least one right turning path candidate TRa'C set and the center line CL of the road R intersect as a virtual intersection center candidate VCTRC, which is a candidate for the virtual intersection center VCTR, and sets a point at which the right turning path candidate TRa'C and the straight traveling path TRb' as a virtual straight line that passes the center of the lane L22 and is parallel to the center line CL intersect as a virtual predicted collision point candidate VCPPC, which is a candidate for the virtual predicted collision point VCPP, in an associated manner on the road map. At this time, the virtual area setting unit B122a also sets a virtual intersection candidate VCSC, which is a candidate for the virtual intersection VCS corresponding to each virtual intersection center candidate VCTRC, in an associated manner on the road map.

[0110] Next, the virtual area setting unit B122a sets the virtual intersection area candidate VACSC that is a candidate for the virtual intersection area VACS and includes each virtual intersection center candidate VCTRC and the virtual predicted collision area candidate VACPC that is a candidate for the virtual predicted collision area VACP and includes each virtual predicted collision point candidate VCPPC in an associated manner on the road map.

[0111] Then, the virtual area setting unit B122a determines the predetermined area PA from among at least one predetermined area candidate PAC in a case where the aforementioned predetermined setting condition to set the virtual intersection area candidate VACSC and the virtual predicted collision area VACP is met, and thereby determines the determined predetermined area PA, that is, the right turning path candidate TRa'C, the virtual intersection center candidate VCTRC, the virtual predicted collision point candidate VCPPC, the virtual intersection area candidate VACSC, and the virtual predicted collision area candidate VACPC as the right turning path TRa', the virtual intersection center VCTR, the virtual predicted collision point VCPP, the virtual intersection area VACS, and the virtual predicted collision area VACP, respectively.

[0112] The virtual area setting unit B122a sets and holds the predetermined area candidate PAC that the right turning vehicle VA may turn right and enter, the virtual intersection area candidate VACSC, the virtual predicted collision area candidate VACPC, and the like associated with the predetermined area candidate PAC in advance in this manner before the predetermined setting condition to set the virtual intersection area VACS and the virtual predicted collision area VACP is met. The processing to generate the virtual intersection area VACS, the virtual predicted collision area VACP, and the like on the basis of the right turning path TRa' after the predetermined setting condition is met becomes unnecessary, which leads to a decrease in calculation load. In this manner, the virtual area setting unit B122a shortens the setting processing time for the virtual intersection area VACS and the virtual predicted collision area VACP, allowing for the setting of the virtual intersection area VACS and the virtual predicted collision area VACP with no delay, thereby improving accuracy when the notification in a predetermined mode is performed.

[0113] Furthermore, the virtual area setting unit B122a may use at least one of the steering amount of the right turning vehicle VA detected by the steering angle sensor 114a, which serves as the steering amount detection and notification section, and the vehicle speed VSPa of the right turning vehicle VA to determine the predetermined area PA from among at least one predetermined area candidate PAC. In other words, the virtual area setting unit B122a may determine the predetermined area PA from among at least one predetermined area candidate PAC on the basis of at least one of the steering amount of the right turning vehicle VA detected by the steering angle sensor 114a as the steering amount detection and notification section and the vehicle speed VSPa of the right turning vehicle VA.

[0114] Specifically, the method of setting the right turning path TRa' on the basis of the specific distance Dpa illustrated in Fig. 25 described above is partially used. In other words, correction is performed to shorten the specific distance Dpa as the change in steering angle in the rightward direction of the right turning vehicle VA is greater and / or as the decrease in vehicle speed VSPa of the right turning vehicle VA is greater after the right turn intention of the right turning vehicle VA is detected, and a predetermined area candidate PAC that is the closest from the point Ps on the road R separated from the position of the right turning vehicle VA at the point where the right turn intention of the right turning vehicle VA is detected on the front side by the specific distance Dpa after the correction as the predetermined area PA. In this manner, the virtual area setting unit B122a can set the virtual intersection area VACS and the virtual predicted collision area VACP accurately and without delay, enabling more precise notification in the predetermined mode.

[0115] In the present embodiment, the controller 101a included in the right turning vehicle VA and the controller 101b included in the straight traveling vehicle VB have basically similar configurations and include mutually corresponding elements.

[0116] As illustrated in Fig. 3, the controller 101b of the straight traveling vehicle VB includes a host vehicle position detection unit B111b, an other vehicle position detection unit B112b, a road map storage unit B113b, a right turn intention detection unit B114b, a vehicle speed detection unit B115b, a first vehicle behavior detection unit B116b, a second vehicle behavior detection unit B117b, a first notification issuing unit B118b, a second notification issuing unit B119b, a third vehicle behavior detection unit B120b, a fourth vehicle behavior detection unit B121b, and a virtual area setting unit B122b. Differences between an internal configuration of the controller 101b and that of the controller 101a of the right turning vehicle VA will be mainly described below.

[0117] The host vehicle position detection unit B111b is adapted to detect the current position Pb of the straight traveling vehicle VB, which is the host vehicle, and the detection of the current position Pb is based on an output signal from the position sensor 111b included in the straight traveling vehicle VB.

[0118] The other vehicle position detection unit B112b is adapted to detect the current position Pa of the right turning vehicle VA, which is another vehicle, and the detection of the current position Pa is based on reading of position information indicating the current position Pa from vehicle information acquired from the right turning vehicle VA via the receiver 122b included in the straight traveling vehicle VB.

[0119] Similarly to the road map storage unit B113a, the road map storage unit B113b stores a road map that includes the intersection CS and includes an assigned link ID of each lane leading to the intersection CS (a map in a range or a section including the intersection CS) and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA, respectively, on the road map. Similarly to the road map storage unit B113a, the road map storage unit B113b stores a road map that includes an assigned link ID of each lane leading to the virtual intersection VCS (a map in a specific range or a specific section) and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA, respectively, on the road map. Although the road maps stored in the road map storage units B113b and B113a may have different levels of accuracy, both the road map storage units B113b and B113a employ maps with accuracy that is compatible with satellite positioning based on a GNSS in the present embodiment. Additionally, the road map stored in the road map storage unit B113b includes the position information of roadside buildings RB and the position information of the median strip of the road R similarly to the road map stored in the road map storage unit B113a.

[0120] Note that the road maps stored in the road map storage unit B113b and the road map storage unit B113a can be updated to the latest road map saved in a remote server by causing the straight traveling vehicle VB and the right turning vehicle VA to communicate with the remote server, or the road maps can be updated to the latest road map saved in a portable storage medium (storage device) that saves the latest road map by connecting the storage medium to the straight traveling vehicle VB and the right turning vehicle VA.

[0121] The right turn intention detection unit B114b is adapted to detect a right turn intention of the right turning vehicle VA, and the detection of the right turn intentin is based on reading of information indicating an operating status of the right turn signal from vehicle information acquired from the right turning vehicle VA via the receiver 122b or identification of the link ID of the lane where the right turning vehicle VA is present from the current position Pa of the right turning vehicle VA in a case where the right turning vehicle VA turns right at the intersection CS. It is also possible to include the link IDs of the lanes where the vehicles VA and VB are present in vehicle information exchanged between the straight traveling vehicle VB and the right turning vehicle VA and to detect the right turn intention of the right turning vehicle VA on the basis of the link IDs acquired through communication.

[0122] The vehicle speed detection unit B115b is adapted to detect the vehicle speed VSPa of the right turning vehicle VA, and the detection thereof is based on reading of vehicle speed information indicating the vehicle speed VSPa from vehicle information acquired from the right turning vehicle VA via the receiver 122b.

[0123] The first vehicle behavior detection unit B116b detects that the right turning vehicle VA is located at a predetermined relative position with reference to the first predetermined position P1 relative to the intersection CS after showing its right turn intention. Specifically, the first vehicle behavior detection unit B116b compares the current position Pa of the right turning vehicle VA on the road map with the intersection area ACS and detects that the right turning vehicle VA has arrived at the intersection area ACS or has entered the intersection area ACS similarly to the above description. Then, the first vehicle behavior detection unit B116b sets a timing at which any of these behaviors of the right turning vehicle VA is detected as a first notification issuance timing. The first notification issuance timing set by the first vehicle behavior detection unit B116b is a timing at which the straight traveling vehicle VB performs notification issuance in the first predetermined mode.

[0124] The size and the shape of the intersection area ACS may be the same or different between the controller 101a of the right turning vehicle VA and the controller 101b of the straight traveling vehicle. It is possible to set the size of the intersection area ACS to be variable or to change the shape thereof in accordance with a drivers' selection or trends of driving states at the time of passing the intersection CS, for example.

[0125] The second vehicle behavior detection unit B117b monitors a behavior of the right turning vehicle VA after the right turning vehicle VA enters the intersection CS and detects that the right turning vehicle VA is traveling toward the predicted collision point CPP in the intersection area ACS or is present inside the predicted collision area ACP after entering the intersection area ACS. Then, the second vehicle behavior detection unit B117b sets a timing at which any of these behaviors of the right turning vehicle VA is detected as a second notification issuance timing. The second notification issuance timing set by the second vehicle behavior detection unit B117b is a timing at which the straight traveling vehicle VB performs notification issuance in the second predetermined mode.

[0126] Although the size and the shape of the predicted collision area ACP may be different between the controller 101a and the controller 101b, similar setting is adopted for both in the present embodiment. The predicted collision area ACP may be preset as default coordinates on the road map, or coordinate information of the predicted collision area ACP set in one of the controllers 101a and 101b may be provided to and set in the other controller through vehicle-to-vehicle communication.

[0127] The first notification issuing unit B118b outputs a command signal to issue the notification in the first predetermined mode to the HMI device 131b included in the host vehicle (that is, the straight traveling vehicle VB) under a condition that the first predetermined notification issuance condition related to the position Pb of the straight traveling vehicle VB is established at a timing at which the arrival of the right turning vehicle VA at the intersection area ACS or entrance thereof to the intersection area ACS is detected, that is, at the first notification issuance timing. Similarly to the above description, the first predetermined notification issuance condition is that the straight traveling vehicle VB is located at the information presentation distance Dth1 from the intersection CS or is present at a position closer to the intersection CS than the information presentation distance Dth1. The output of the command signal to perform the notification issuance in the first predetermined mode from the first notification issuing unit B118b to the HMI device 131b is regarded as "execution of the notification issuance in the first predetermined mode".

[0128] The HMI device 131b that has received the command signal from the first notification issuing unit B118b issues a notification to promote the driver of the straight traveling vehicle VB to recognize that the right turning vehicle VA which the driver should pay attention to is present in the right turn lane L11 in the opposite lanes using display and sound. Similarly to the above description, the notification issuance performed by the first notification issuing unit B118b is notification issuance to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA.

[0129] The second notification issuing unit B119b outputs the command signal to perform the notification issuance in the second predetermined mode, which is a command signal to issue a notification in the second predetermined mode, to the HMI device 131b under a condition that the second predetermined notification issuance condition related to the position Pb of the straight traveling vehicle VB is established at a timing at which traveling of the right turning vehicle VA toward the predicted collision point CPP in the intersection area ACS or presence thereof inside the predicted collision area ACP is detected, that is, at the second notification issuance timing. The second predetermined notification issuance condition is that the straight traveling vehicle VB is located at the alarm distance Dth2 from the intersection CS or is present at a position closer to the intersection CS than the alarm distance Dth2. The output of the command signal to perform the notification issuance in the second predetermined mode from the second notification issuing unit B119b to the HMI device 131b is regarded as "execution of the notification issuance in the second predetermined mode".

[0130] The HMI device 131b that has received the command signal from the second notification issuing unit B119b issues a notification to promote the driver of the straight traveling vehicle VB to recognize higher urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA using display and sound. Similarly to the above description, the notification issuance performed by the second notification issuing unit B119a is also notification issuance that is more prominent and more visually or auditorily appealing to the driver.

[0131] The information presentation distance Dth1 and the alarm distance Dth2 may be set to equal distances between the controller 101a and the controller 101b or may be set to different distances therebetween. For example, a deceleration degree when the straight traveling vehicle VB has actually decelerated in response to an alarm is learned, and the deceleration degrees used when the distances Dth1 and Dth2 are calculated are corrected on the basis of a learned value that indicates the actual deceleration degree. Specifically, in a case where the actual deceleration in response to an alarm tends to be slow as compared with the case of the deceleration degree DEC2, the deceleration degrees DEC1 and DEC2 are corrected to decrease, such that the notification issuance for each of the information presentation and the alarm can be performed at an earlier timing.

[0132] The first notification issuing unit B118b and the second notification issuing unit B119b can also notify the right turning vehicle VA of the fact that the notification in each mode (the notification issuance in the first predetermined mode and the notification issuance in the second predetermined mode) has been issued via the transmitter 121b in accordance with the output of the command signal to the HMI device 131b.

[0133] The third vehicle behavior detection unit B120b detects that the right turning vehicle VA is present at a predetermined position relative to the virtual intersection VCS. Specifically, the third vehicle behavior detection unit B120b compares the current position Pa of the right turning vehicle VA on the road map with the virtual intersection area VACS and detects that the right turning vehicle VA has arrived at the virtual intersection area VACS or has entered the virtual intersection area VACS similarly to the above description. Then, the third vehicle behavior detection unit B120b sets a timing at which any of these behaviors of the right turning vehicle VA is detected as a third notification issuance timing. The third notification issuance timing set by the third vehicle behavior detection unit B120b is a timing at which the straight traveling vehicle VB performs notification issuance in the third predetermined mode.

[0134] The size and the shape of the virtual intersection area VACS may be the same or different between the controller 101a and the controller 101b. It is possible to set the size of the virtual intersection area VACS to be variable or to change the shape thereof in accordance with a drivers' selection or trends of driving states at the time of passing the virtual intersection VCS, for example.

[0135] The fourth vehicle behavior detection unit B121b monitors a behavior of the right turning vehicle VA after the setting of the third notification issuance timing. In other words, the fourth vehicle behavior detection unit B121b monitors a behavior of the right turning vehicle VA after entering the virtual intersection area VACS. The fourth vehicle behavior detection unit B121b detects whether the right turning vehicle VA is traveling toward the virtual predicted collision point VCPP inside the virtual intersection area VACS or is present inside the virtual predicted collision area VACP on the basis of the current position Pa of the right turning vehicle VA on the road map. Then, the fourth vehicle behavior detection unit B121b sets the timing at which any of these behaviors of the right turning vehicle VA is detected as a fourth notification issuance timing. The fourth notification issuance timing set by the fourth vehicle behavior detection unit B121b is a timing at which the straight traveling vehicle VB performs notification issuance in the fourth predetermined mode.

[0136] Although the size and the shape of the virtual predicted collision area VACP may be different between the controller 101a of the right turning vehicle and the controller 101b of the straight traveling vehicle, similar setting is adopted for both in the present embodiment. The virtual predicted collision area VACP may be set to have the same size and shape in each of the controller 101a and the controller 101b, or coordinate information of the virtual predicted collision area VACP set in one of the controllers 101a and 101b may be provided to and set in the other controller through vehicle-to-vehicle communication.

[0137] The first notification issuing unit B118b outputs a command signal to perform the notification issuance in the third predetermined mode to the HMI device 131b included in the host vehicle (that is, the straight traveling vehicle VB) under the condition that a third predetermined notification issuance condition defined in advance in regard to the position Pb of the straight traveling vehicle VB, is met at the third notification issuance timing set by the third vehicle behavior detection unit B120b. Similarly to the above description, the third predetermined notification issuance condition is that the straight traveling vehicle VB is present at the information presentation distance Dth3 from the virtual intersection VCS or at a position closer to the virtual intersection VCS than the information presentation distance Dth3. The output of the command signal to perform the notification issuance in the third predetermined mode from the first notification issuing unit B118b to the HMI device 131b is regarded as "execution of the notification issuance in the third predetermined mode".

[0138] The HMI device 131b that has received the command signal to perform the notification issuance in the third predetermined mode from the first notification issuing unit B118b issues a notification to promote the driver of the straight traveling vehicle VB to recognize that the right turning vehicle VA which the driver should pay attention to is present in the lane L11, which is an opposite lane, using display and sound. Similarly to the above description, the notification issuance performed by the first notification issuing unit B118b is notification issuance to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA.

[0139] The second notification issuing unit B119b outputs a command signal to issue a notification in a fourth predetermined mode to the HMI device 131b under a condition that a fourth predetermined notification issuance condition defined in advance in regard to the position Pb of the straight traveling vehicle VB is established at the fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a. Similarly to the above description, the fourth predetermined notification issuance condition is that the straight traveling vehicle VB is present at the alarm distance Dth4 from the virtual intersection VCS or at a position closer to the virtual intersection VCS than the alarm distance Dth4.

[0140] The HMI device 131b that has received the command signal to perfomr the notification issuance in the fourth predetermined mode from the second notification issuing unit B119b issues a notification to promote the driver of the straight traveling vehicle VB to recognize higher urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA using display and sound. Similarly to the above description, the notification issuance performed by the second notification issuing unit B119b is also notification issuance that is more prominent and more visually or auditorily appealing to the driver.

[0141] The first notification issuing unit B118b and the second notification issuing unit B119b can also provide a notification that the notification issuance in each mode (the notification issuance in the third predetermined mode and the notification issuance in the fourth predetermined mode) has been performed to the right turning vehicle VA via the transmitter 121b together with the output of the command signal to the HMI device 131b.

[0142] The information presentation distance Dth3 and the alarm distance Dth4 may be set to equal distances between the controller 101a and the controller 101b or may be set to different distances therebetween. For example, a deceleration degree when the straight traveling vehicle VB has actually decelerated in response to an alarm is learned, and the deceleration degrees used when the distances Dth3 and Dth4 are calculated are corrected on the basis of a learned value that indicates the actual deceleration degree. Specifically, in a case where the actual deceleration in response to an alarm tends to be slow as compared with the case of the deceleration degree DEC4, the deceleration degrees DEC3 and DEC4 are corrected to decrease, such that the notification issuance for each of the information presentation and the alarm can be performed at an earlier timing.

[0143] Similarly to the above description, the virtual area setting unit B122b sets the virtual intersection area VACS and the virtual predicted collision area VACP in an associated manner on the road map in a case where the right turning vehicle VA is present in the traveling lane L11 while the straight traveling vehicle VB is present in the opposite lane L22 and the right turn intention of the right turning vehicle VA. Specifically, the virtual area setting unit B122b sets the virtual intersection area VACS and the virtual predicted collision area VACP on the map in the specific range or the specific section extracted by the road map storage unit B113a. The right turning path TRa' of the right turning vehicle VA, which used in setting the virtual intersection area VACS and the virtual predicted collision area VACP, is set by the virtual area setting unit B122b in the same manner as described above.

[0144] Similarly to the above description, the first notification issuing unit B118b may not output the command signal to perform the notification issuance in the third predetermined mode, and the second notification issuing unit B119b may not output the command signal to perform the notification issuance in the fourth predetermined mode in a case where the right turning vehicle VA enters the intersection area ACS. Also, the virtual area setting unit B122b may not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB exceeds the predetermined separation distance Dth5, which is a relatively long distance, similarly to the above description. Other preferred aspects related to the virtual area setting unit B122b are similar to other preferred aspects related to the virtual area setting unit B122a, and description thereof will thus be omitted.(Content of Notification Control in Right Turning Vehicle Turning Right at Intersection)

[0145] Figs. 4 to 6 are flowcharts illustrating content of notification control performed by the controller 101a included in the right turning vehicle VA in a case where the right turning vehicle VA turns right at the intersection CS. The flowchart in Fig. 4 illustrates an overall flow of the notification control, the flowchart in Fig. 5 illustrates content of processing (information presentation processing) executed by the right turning vehicle VA in regard to information presentation, and the flowchart in Fig. 6 illustrates content of processing (alarm processing) executed by the right turning vehicle VA in regard to an alarm. The information presentation processing and the alarm processing are performed as parts of the notification control. The controller 101a performs the notification control every predetermined time in a case where an intersection CS is detected in a road R in front of the host vehicle (that is, the right turning vehicle VA).

[0146] In the flowchart illustrated in Fig. 4, the controller 101a read various kinds of control information used for the notification control in S111. The control information read in S111 includes the current position Pa, the vehicle speed VSPa, and the link ID of the right turning vehicle VA, which is a host vehicle, and the current position Pb, the vehicle speed VSPb, and the link ID of the straight traveling vehicle VB, which is another vehicle. The control information may include information regarding operating statuses of the right turn signals in the right turning vehicle VA and the straight traveling vehicle VB.

[0147] In S112, the controller 101a determines whether the right turning vehicle VA has detected the straight traveling vehicle VB in the straight direction toward the intersection CS in the lane L22 opposite to the lane L11 in which the right turning vehicle VA is present. The detection of the straight traveling vehicle VB is based on the link ID of straight traveling vehicle VB. The processing proceeds to S113 in a case where the straight traveling vehicle VB is detected, or this control is ended in a case where the straight traveling vehicle VB is not detected.

[0148] In S113, the controller 101a determines whether a right turn intention of the right turning vehicle VA has been detected. The detection of the right turn intention is based on an operating status of the right turn signal of the right turning vehicle VA. Additionally or alternatively, it is also possible to make the determination on the basis of the link ID of the right turning vehicle VA. In a case where the right turn lane L11 is a lane only for right turn, for example, the right turn intention of the right turning vehicle VA may also be detected by the fact that the lane where the right turning vehicle VA is traveling is the right turn lane L11. The processing proceeds to S114 in a case where the right turn intention is detected, or this control is ended in a case where the right turn intention is not detected.

[0149] In S114, the controller 101a specifies the current position Pa of the right turning vehicle VA on the road map.

[0150] In S115, the controller 101a determines whether the right turning vehicle VA has entered the intersection area ACS. In a case where the right turning vehicle VA is located at a position of the outer edge of the intersection area ACS (that is, the first predetermined position P1) or is located at a position closer to the intersection center CTR than the position of the outer edge, and the right turning vehicle VA has entered the intersection area ACS, the processing proceeds to S116. On the other hand, in a case where the right turning vehicle VA has not entered the intersection area ACS and is located at a position farther from the intersection center CTR than the outer edge of the intersection area ACS, this control is ended.

[0151] In S116, the controller 101a performs the information presentation processing. The information presentation processing follows a procedure illustrated in the flowchart in Fig. 5.

[0152] In S117, the controller 101a performs the alarm processing. The alarm processing follows a procedure illustrated in the flowchart in Fig. 6.

[0153] In S118, the controller 101a determines whether the right turning vehicle VA has passed the intersection CS. The determination of whether the right turning vehicle VA has passed the intersection CS is made based on the fact that the right turning vehicle VA has left the intersection area ACS in the traveling direction after turning right. This control is ended in a case where the right turning vehicle VA has passed the intersection CS, or the processing returns to S116 to repeat the information presentation processing and the alarm processing until the right turning vehicle VA passes the intersection area ACS in a case where the right turning vehicle VA has not passed the intersection CS and is still in the intersection area ACS.

[0154] In the flowchart illustrated in Fig. 5, the controller 101a reads various kinds of control information used for the information presentation processing in S211. The control information read in S211 includes the current position Pa and the vehicle speed VSPa of the right turning vehicle VA and the current position Pb and the vehicle speed VSPb of the straight traveling vehicle VB.

[0155] In S212, the controller 101a specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map.

[0156] In S213, the controller 101a determines whether the right turning vehicle VA is located outside the predicted collision area ACP. _In a case where the right turning vehicle VA is located between the position of the outer edge of the intersection area ACS and the position of the outer edge of the predicted collision area ACP (that is, the second predetermined position P2) and is located outside the predicted collision area ACP, the processing proceeds to S214. When using the operating status of the right turn signal in order to detect the right turn intention of the right turning vehicle VA, the controller 101a may determine whether the operation of the right turn signal is being continued in addition to the processing in S213 and perform the processing in and after S214 in a case where the operation of the right turn signal is being continued. On the other hand, in a case where the right turning vehicle VA is located at the outer edge of the predicted collision area ACP or a position closer to the predicted collision point CPP than the outer edge and is not located outside the predicted collision area ACP, the information presentation processing is ended.

[0157] In S214, the controller 101a reads the vehicle speed VSPa of the right turning vehicle VA.

[0158] In S215, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than a predetermined vehicle speed VSP1. The predetermined vehicle speed VSP1 is a low speed that is low enough to determine that the right turning vehicle VA is in a low-speed traveling state and is a reduced speed (specifically, 10 km / hour), for example. In the present embodiment, it is determined that the driver of the right turning vehicle VA is paying attention to the surrounding situation to pass the intersection CS by the fact that the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. The processing proceeds to S216 in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, or the information presentation processing is ended in a case where the vehicle speed VSPa is greater than the vehicle speed VSP1. The predetermined vehicle speed VSP1 may be 0 km / hour, and in other words, S215 may be processing of determining whether the right turning vehicle VA has temporarily stopped inside the intersection area ACS. Furthermore, it is also possible to eliminate the processing in S215 itself, and the notification issuance for an alarm may be prioritized over the notification issuance for the information presentation in a case where a notification issuance condition for the information presentation (S220) and the notification issuance condition for the alarm (S320) are established at the same time.

[0159] In this manner, in a case where the right turning vehicle VA has maintained the low vehicle speed VSPa until the arrival at the predicted collision area ACP or has sufficiently decelerated (including the case of temporarily stopping) after entering the intersection area ACS, the controller 101a of the present embodiment determines that a notification issuance timing for the information presentation (that is, the first notification issuance timing) has arrived on the basis of the detection of the vehicle speed VSPa that is equal to or less than the predetermined vehicle speed VSP1, performs the processing in and after S216 is performed, and determines whether the first predetermined notification issuance condition has been established. The notification issuance timing for the information presentation is not limited thereto, and it is possible to set the notification issuance timing for the information presentation on the basis of the entrance of the right turning vehicle VA to the intersection area ACS, in other words, on the basis of the right turning vehicle VA being located inside the intersection area ACS, without providing any limitations based on a driving state such as the vehicle speed VSPa.

[0160] In S216, the controller 101a calculates the distance from intersection CS to the straight traveling vehicle VB, in other words, a distance Db remaining in front of the straight traveling vehicle VB until arriving at the intersection CS (hereinafter, referred to as an "intersection arrival distance"). As illustrated in Fig. 12, the intersection arrival distance Db is calculated as the distance from the outer edge of the predicted collision area ACP to the straight traveling vehicle VB, and the calculation is based on the current position Pb of the straight traveling vehicle VB.

[0161] In S217, the controller 101a reads the vehicle speed VSPb of the straight traveling vehicle VB.

[0162] In S218, the controller 101a calculates the information presentation distance Dth1. The calculation of the information presentation distance Dth1 is based on the vehicle speed VSPb of the straight traveling vehicle VB and the first predetermined deceleration degree DEC1 as described above.

[0163] In S219, the controller 101a determines whether the intersection arrival distance Db of the straight traveling vehicle VB is equal to or less than the information presentation distance Dth1, in other words, whether the straight traveling vehicle VB is located at the information presentation distance Dth1 from the intersection CS or is located at a position closer to the intersection CS than the information presentation distance Dth1. The processing proceeds to S220 in a case where the intersection arrival distance Db is equal to or less than the information presentation distance Dth1, or the information presentation processing is ended in a case where the intersection arrival distance Db is greater than the information presentation distance Dth1.

[0164] In S220, the controller 101a performs notification issuance for information presentation.

[0165] In the flowchart illustrated in Fig. 6, the controller 101a reads various kinds of control information used for the alarm processing in S311. The control information read in S311 includes the current position Pa and the vehicle speed VSPa of the right turning vehicle VA and the current position Pb and the vehicle speed VSPb of the straight traveling vehicle VB.

[0166] In S312, the controller 101a specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map.

[0167] In S313, the controller 101a determines whether the right turning vehicle VA is located inside the predicted collision area ACP. In a case where the right turning vehicle VA is located at the position of the outer edge of the predicted collision area ACP (that is, the second predetermined position P2) or is located at the position closer to the predicted collision point CPP than the position of the outer edge and the right turning vehicle VA is located inside the predicted collision area ACP, the processing proceeds to S316. On the other hand, in a case where the right turning vehicle VA is located at a position farther from the predicted collision point CPP than the outer edge of the predicted collision area ACP and is not located inside the predicted collision area ACP, the processing proceeds to S314. In a case where the operating status of the right turn signal is used to detect the right turn intention of the right turning vehicle VA, the fact that the operation of the right turn signal is being continued may be included as a condition of performing the processing as a premise of performing the processing in S313.

[0168] In S314, the controller 101a reads the vehicle speed VSPa of the right turning vehicle VA.

[0169] In S315, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is higher than the predetermined vehicle speed VSP1. The processing proceeds to S316 in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1, or the alarm processing is ended in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. In other words, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is greater than the vehicle speed VSP1 achieved in the low-speed traveling state, for example, a speed reduced state, and in a case where the vehicle speed VSPa is greater than the vehicle speed VSP1, the controller 101a determines that the driver of the right turning vehicle VA is not paying attention to the surrounding situation, and the processing proceeds to S316. On the other hand, in a case where the vehicle speed VSPa is equal to or less than the vehicle speed VSP1, the controller 101a determines that the notification should be issued for the information presentation in the situation and ends the alarm processing.

[0170] In this manner, the controller 101a determines that a notification issuance timing for an alarm (that is, the second notification issuance timing) has arrived on the basis of detection of a situation in which the right turning vehicle VA has arrived at the predicted collision area ACP and has already been in the predicted collision area ACP after entering the intersection area ACS or the right turning vehicle VA is traveling at a speed that is equal to or greater than a specific speed toward the predicted collision point CPP even outside the predicted collision area ACP and is approaching the predicted collision area ACP in S313 to S315, performs the processing in and after S316, and determines whether the second predetermined notification issuance condition is established.

[0171] In S316, the controller 101a calculates the intersection arrival distance Db of the straight traveling vehicle VB.

[0172] In S317, the controller 101a reads the vehicle speed VSPb of the straight traveling vehicle VB.

[0173] In S318, the controller 101a calculates the alarm distance Dth2. The calculation of the alarm distance Dth2 is based on the vehicle speed VSPb of the straight traveling vehicle VB and the second predetermined deceleration degree DEC2 as described above.

[0174] In S319, the controller 101a determines whether the intersection arrival distance Db of the straight traveling vehicle VB is equal to or less than the alarm distance Dth2, in other words, whether the straight traveling vehicle VB is located at the alarm distance Dth2 from the intersection CS or is located at a position closer to the intersection CS than the alarm distance Dth2. The processing proceeds to S320 in the case where the intersection arrival distance Db is equal to or less than the alarm distance Dth2, or the alarm processing is ended in a case where the intersection arrival distance Db is greater than the alarm distance Dth2.

[0175] In S320, the controller 101a performs the notification issuance for the alarm.(Content of Notification Control in Straight Traveling Vehicle Traveling straight across Intersection)

[0176] Figs. 7 to 9 are flowcharts illustrating content of notification control performed by the controller 101b included in the straight traveling vehicle VB when the straight traveling vehicle VB travels straight across the intersection CS. The flowchart in Fig. 7 illustrates an overall flow of the notification control, the flowchart in Fig. 8 illustrates content of the information presentation processing executed by the straight traveling vehicle VB, and the flowchart in Fig. 9 illustrates content of the alarm processing executed by the straight traveling vehicle VB. The controller 101b performs the notification control every predetermined time in a case where an intersection CS is detected in a road R in front of the host vehicle. The execution cycles of the notification control may be the same or different between the controller 101a and the controller 101b. Furthermore, both the controllers 101a and 101b can also perform the notification control in a synchronized manner.

[0177] Each process performed by the controller 101a and the controller 101b in regard to the notification control at the intersection CS corresponds to each other. Therefore, detailed description of the processes that are similar for both will be omitted in the following description.

[0178] In the flowchart illustrated in Fig. 7, the controller 101b read various kinds of control information used for the notification control (S411), detects another vehicle that is present in the right turn lane L11 in the opposite lanes, that is, the right turning vehicle VA (S412), and then determines whether the right turn intention of the right turning vehicle VA, which is another vehicle, has been detected in S413. After detecting the right turn intention, the controller 101b specifies the current position Pa of the right turning vehicle VA on the road map (S414), and determines whether the right turning vehicle VA has entered the intersection area ACS (S415). The controller 101b executes the procedure in and after S416 in a case where the right turning vehicle VA has entered the intersection area ACS, or ends this control in a case where the right turning vehicle VA has not entered the intersection area ACS. The controller 101b executes the information presentation processing in S416 and the alarm processing in S417. The information presentation processing and the alarm processing are repeated until the right turning vehicle VA passes the intersection area ACS.

[0179] In the flowchart illustrated in Fig. 8, the controller 101b reads various kinds of control information used for the information presentation processing, such as the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA (S511), and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map (S512). In S513, the controller 101b determines whether the right turning vehicle VA, which is another vehicle, is located outside the predicted collision area ACP, reads the vehicle speed VSPa of the right turning vehicle VA (S514) in a case where the controller 101b determines that the right turning vehicle VA is located outside the predicted collision area ACP, and determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the predetermined vehicle speed VSP1 (S515). The controller 101b performs the processing in and after S516 in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, or ends the information presentation processing in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1. When using the operating status of the right turn signal in order to detect the right turn intention of the right turning vehicle VA, the controller 101b may determine whether the operation of the right turn signal is being continued in addition to the processing in S513, and execute the processing in and after S514 in a case where the operation of the right turn signal is being continued. Then, the controller 101b calculates the intersection arrival distance Db of the straight traveling vehicle VB, which is the host vehicle (S516), reads the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) (S517), and calculates the information presentation distance Dth1 (S518). The processing proceeds to S520 to issue a notification for information presentation in a case where the intersection arrival distance Db is equal to or less than the information presentation distance Dth1 (S519), or the information presentation processing is ended in a case where the intersection arrival distance Db is greater than the information presentation distance Dth1.

[0180] In the flowchart illustrated in Fig. 9, the controller 101b reads various kinds of control information used for the alarm processing such as the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA (S611), and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map are (S612). The controller 101b determines whether the right turning vehicle VA, which is another vehicle, is located inside the predicted collision area ACP, in S613, reads the vehicle speed VSPa of the right turning vehicle VA (S614) in a case where the right turning vehicle VA is determined not to be located inside the predicted collision area ACP, and determines whether the vehicle speed VSPa of the right turning vehicle VA is greater than the predetermined vehicle speed VSP1 (S615). The controller 101b performs the processing in and after S616 in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1, or ends the alarm processing in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. In a case where the operating status of the right turn signal is used to detect the right turn intention of the right turning vehicle VA, the fact that the operation of the right turn signal is being continued may be included in the condition of performing the processing as a premise of performing the processing in S613. Then, the controller 101b calculates the intersection arrival distance Db of the straight traveling vehicle VB, which is a host vehicle (S616), reads the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) (S617), and calculates the alarm distance Dth2 (S618). The processing proceeds to S620 to issue a notification for the alarm in a case where the intersection arrival distance Db is equal to or less than the alarm distance Dth2, or the alarm processing is ended in a case where the intersection arrival distance Db is greater than the alarm distance Dth2.(Content of Notification Control in Right Turning Vehicle Turning Right at Virtual Intersection)

[0181] Figs. 15 to 17 are flowcharts illustrating content of notification control performed by the controller 101a included in the right turning vehicle VA in a case where the right turning vehicle VA turns right at the virtual intersection VCS. The flowchart in Fig. 15 illustrates an overall flow of the notification control, the flowchart in Fig. 16 illustrates content of processing (information presentation processing) executed by the right turning vehicle VA in regard to information presentation, and the flowchart in Fig. 17 illustrates content of processing (alarm processing) executed by the right turning vehicle VA in regard to an alarm. The information presentation processing and the alarm processing are performed as parts of the notification control. The controller 101a performs the notification control every predetermined time.

[0182] In the present embodiment, the controller 101a can process the aforementioned notification control for the right turning vehicle VA turning right at the intersection CS and the notification control for the right turning vehicle VA turning right at the virtual intersection VCS in parallel. For convenience of explanation, it is assumed that the right turning vehicle VA does not enter the intersection area ACS in the notification control illustrated in Figs. 15 to 17 and Figs. 18 to 20, which will be described later.

[0183] In the flowchart illustrated in Fig. 15, the controller 101a read various kinds of control information used for the notification control in S1111. The control information read in S1111 includes the current position Pa, the vehicle speed VSPa, and the link ID of the right turning vehicle VA, which is a host vehicle, and the operating statuses of the right turn signals in the right turning vehicle VA, and the current position Pb, the vehicle speed VSPb, and the link ID of the straight traveling vehicle VB, which is another vehicle, and the operating statuses of the right turn signals in the straight traveling vehicle VB. The control information read in S1111 may include the steering information and the destination information of the right turning vehicle VA, and the steering information and the destination information of the straight traveling vehicle VB.

[0184] In S1112, the controller 101a determines whether the right turning vehicle VA has detected the straight traveling vehicle VB in the straight direction in the lane L22 opposite to the lane L11 in which the right turning vehicle VA is present. The detection of the straight traveling vehicle VB is based on the link ID of straight traveling vehicle VB. The processing proceeds to S113 in a case where the straight traveling vehicle VB is detected, or this control is ended in a case where the straight traveling vehicle VB is not detected. In a case where the straight traveling vehicle VB is detected in S1112, the condition that the right turning vehicle VA is present in the lane 11 and the straight traveling vehicle VB is present in the opposite lane L22 is established.

[0185] In S1113, the controller 101a determines whether a right turn intention of the right turning vehicle VA has been detected. The detection of the right turn intention is based on an operating status of the right turn signal of the right turning vehicle VA. The processing proceeds to S1114 in a case where the right turn intention is detected, or this control is ended in a case where the right turn intention is not detected.

[0186] In S1114, the controller 101a determines whether the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB is equal to or less than the predetermined separation distance Dth5. The distance Dab between the right turning vehicle VA and the straight traveling vehicle VB is based on the current position Pa of the right turning vehicle VA and the current position Pb of the straight traveling vehicle VB. The processing proceeds to S1115 in a case where the distance Dab is equal to or less than the predetermined separation distance Dth5, or this control is ended in a case where the distance Dab is not equal to or less than the predetermined separation distance Dth5. Not that it is also possible to eliminate the processing in S1114 itself.

[0187] In S1115, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the second predetermined vehicle speed VSP2 that is a vehicle speed higher than the first predetermined vehicle speed VSP1. The processing proceeds to S1116 in a case where the vehicle speed VSPa is equal to or less than a the second predetermined vehicle speed VSP2, or this control is ended in a case where the vehicle speed VSPa is not equal to or less than the second predetermined vehicle speed VSP2. Not that it is also possible to eliminate the processing in S1115 itself.

[0188] In S1116, the controller 101a sets the virtual intersection area VACS and the virtual predicted collision area VACP. As described above, the virtual intersection area VACS and the virtual predicted collision area VACP are based on the right turning path TRa', which is a path where the right turning vehicle VA travels when the right turning vehicle VA turns right at the virtual intersection VCS. The processing of setting the right turning path TRa' and its explanation are omitted.

[0189] In S1117, the controller 101a specifies the current position Pa of the right turning vehicle VA on the road map.

[0190] In S1118, the controller 101a determines whether the right turning vehicle VA has entered the virtual intersection area VACS. In a case where the right turning vehicle VA is located at a position of the outer edge of the virtual intersection area VACS or is located at a position closer to the virtual intersection center VCTR than the position of the outer edge, and the right turning vehicle VA has entered the virtual intersection area VACS, the processing proceeds to S116. On the other hand, in a case where the right turning vehicle VA has not entered the virtual intersection area VACS and is located at a position farther from the virtual intersection VCTR than the outer edge of the virtual intersection area VACS, this control is ended.

[0191] In S1119, the controller 101a performs the information presentation processing. The information presentation processing follows a procedure illustrated in the flowchart in Fig. 16.

[0192] In S1120, the controller 101a performs the alarm processing. The alarm processing follows a procedure illustrated in the flowchart in Fig. 6.

[0193] In S1121, the controller 101a determines whether the right turning vehicle VA has passed the virtual intersection VCS. The determination of whether the right turning vehicle VA has passed the virtual intersection VCS is made based on the fact that the right turning vehicle VA has left the virtual intersection area VACS in the traveling direction after turning right. This control is ended in a case where the right turning vehicle VA has passed the virtual intersection VCS, or the processing returns to S1119 to repeat the information presentation processing and the alarm processing until the right turning vehicle VA passes the virtual intersection area VACS in a case where the right turning vehicle VA is still in the virtual intersection area VACS and has not passed the virtual intersection VCS.

[0194] In the flowchart illustrated in Fig. 16, the controller 101a reads various kinds of control information used for the information presentation processing in S1211. The control information read in S1211 includes the current position Pa and the vehicle speed VSPa of the right turning vehicle VA and the current position Pb and the vehicle speed VSPb of the straight traveling vehicle VB.

[0195] In S1212, the controller 101a specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map.

[0196] In S1213, the controller 101a determines whether the right turning vehicle VA is located outside the virtual predicted collision area VACP. _In a case where the right turning vehicle VA is located between the position of the outer edge of the virtual intersection area VACS and the position of the outer edge of the virtual predicted collision area VACP and is located outside the virtual predicted collision area VACP, the processing proceeds to S1214. On the other hand, in a case where the right turning vehicle VA is located at the outer edge of the virtual predicted collision area VACP or a position closer to the virtual predicted collision point VCPP than the outer edge and is not located outside the virtual predicted collision area VACP, the information presentation processing is ended. Note that the controller 101a may determine whether the operation of the right turn signal, which is used to detect the right turn intention of the right turning vehicle VA, is being continued in addition to the processing in S1213 and perform the processing in and after S1214 in a case where the operation of the right turn signal is being continued.

[0197] In S1214, the controller 101a reads the vehicle speed VSPa of the right turning vehicle VA.

[0198] In S1215, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than a predetermined vehicle speed VSP1. The predetermined vehicle speed VSP1 is as described in S215. In the present embodiment, it is determined that the driver of the right turning vehicle VA is paying attention to the surrounding situation to pass the virtual intersection VCS by the fact that the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. The processing proceeds to S1216 in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, or the information presentation processing is ended in a case where the vehicle speed VSPa is greater than the vehicle speed VSP1. The predetermined vehicle speed VSP1 may be 0 km / hour, and in other words, S1215 may be processing of determining whether the right turning vehicle VA has temporarily stopped inside the intersection area ACS. Furthermore, it is also possible to eliminate the processing in S1215 itself, and the notification issuance for an alarm may be prioritized over the notification issuance for the information presentation in a case where a notification issuance condition for the information presentation (S1220) and the notification issuance condition for the alarm (S1320) are established at the same time.

[0199] In this manner, in a case where the right turning vehicle VA has maintained the low vehicle speed VSPa until the arrival at the virtual predicted collision area VACP or has sufficiently decelerated (including the case of temporarily stopping) after entering the virtual intersection area VACS, the controller 101a of the present embodiment determines that a notification issuance timing for the information presentation (that is, the third notification issuance timing) has arrived on the basis of the detection of the vehicle speed VSPa that is equal to or less than the predetermined vehicle speed VSP1, performs the processing in and after S1216, and determines whether the third predetermined notification issuance condition has been established. The notification issuance timing for the information presentation is not limited thereto, and it is possible to set the notification issuance timing for the information presentation on the basis of the entrance of the right turning vehicle VA to the virtual intersection area VACS, in other words, on the basis of the right turning vehicle VA being located inside the virtual intersection area VACS, without providing any limitations based on a driving state such as the vehicle speed VSPa.

[0200] In S216, the controller 101a calculates the distance from virtual intersection VCS to the straight traveling vehicle VB, in other words, a distance Db' remaining in front of the straight traveling vehicle VB until arriving at the virtual intersection VCS (hereinafter, referred to as a "virtual intersection arrival distance"). As illustrated in Fig. 22, the virtual intersection arrival distance Db' is calculated as the distance from the outer edge of the virtual predicted collision area VACP to the straight traveling vehicle VB, and the calculation is based on the current position Pb of the straight traveling vehicle VB.

[0201] In S1217, the controller 101a reads the vehicle speed VSPb of the straight traveling vehicle VB.

[0202] In S1218, the controller 101a calculates the information presentation distance Dth3. The calculation of the information presentation distance Dth3 is based on the vehicle speed VSPb (= V1') of the straight traveling vehicle VB and the first predetermined deceleration degree DEC3, and is specifically based on the equation (3), as described above.

[0203] In S1219, the controller 101a determines whether the virtual intersection arrival distance Db' of the straight traveling vehicle VB is equal to or less than the information presentation distance Dth3, in other words, whether the straight traveling vehicle VB is located at the information presentation distance Dth3 from the virtual intersection VCS or is located at a position closer to the virtual intersection VCS than the information presentation distance Dth3. The processing proceeds to S1220 in a case where the virtual intersection arrival distance Db' is equal to or less than the information presentation distance Dth3, or the information presentation processing is ended in a case where the virtual intersection arrival distance Db' is greater than the information presentation distance Dth3.

[0204] In S1220, the controller 101a performs notification issuance for information presentation.

[0205] In the flowchart illustrated in Fig. 17, the controller 101a reads various kinds of control information used for the alarm processing in S1311. The control information read in S1311 includes the current position Pa and the vehicle speed VSPa of the right turning vehicle VA and the current position Pb and the vehicle speed VSPb of the straight traveling vehicle VB.

[0206] In S1312, the controller 101a specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map.

[0207] In S1313, the controller 101a determines whether the right turning vehicle VA is located inside the virtual predicted collision area VACP. In a case where the right turning vehicle VA is located at the position of the outer edge of the virtual predicted collision area VACP or is located at the position closer to the virtual predicted collision point VCPP than the position of the outer edge and the right turning vehicle VA is located inside the virtual predicted collision area VACP, the processing proceeds to S1316. On the other hand, in a case where the right turning vehicle VA is located at a position farther from the virtual predicted collision point VCPP than the outer edge of the virtual predicted collision area VACP and is not located inside the virtual predicted collision area VACP, the processing proceeds to S1314. The fact that the operation of the right turn signal is being continued may be included as a condition of performing the processing as a premise of performing the processing in S1313.

[0208] In S1314, the controller 101a reads the vehicle speed VSPa of the right turning vehicle VA.

[0209] In S1315, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is higher than the predetermined vehicle speed VSP1. The processing proceeds to S1316 in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1, or the alarm processing is ended in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1.

[0210] In this manner, the controller 101a determines that a notification issuance timing for an alarm (that is, the fourth notification issuance timing) has arrived on the basis of detection of a situation in which the right turning vehicle VA has arrived at the virtual predicted collision area VACP and has already been in the virtual predicted collision area VACP after entering the virtual intersection area VACS or the right turning vehicle VA is traveling at a speed that is equal to or greater than a specific speed toward the virtual predicted collision point VCPP even outside the virtual predicted collision area VACP and is approaching the virtual predicted collision area VACP in S1313 to S1315, performs the processing in and after S1316, and determines whether the second predetermined notification issuance condition is established.

[0211] In S1316, the controller 101a calculates the virtual intersection arrival distance Db' of the straight traveling vehicle VB.

[0212] In S1317, the controller 101a reads the vehicle speed VSPb of the straight traveling vehicle VB.

[0213] In S1318, the controller 101a calculates the alarm distance Dth4. The calculation of the alarm distance Dth4 is based on the vehicle speed VSPb (= V1') of the straight traveling vehicle VB and the fourth predetermined deceleration degree DEC4, and is specifically based on the equation (4), as described above.

[0214] In S1319, the controller 101a determines whether the virtual intersection arrival distance Db' of the straight traveling vehicle VB is equal to or less than the alarm distance Dth4, in other words, whether the straight traveling vehicle VB is located at the alarm distance Dth4 from the virtual intersection VCS or is located at a position closer to the virtual intersection VCS than the alarm distance Dth4. The processing proceeds to S1320 in the case where the virtual intersection arrival distance Db' is equal to or less than the alarm distance Dth4, or the alarm processing is ended in a case where the virtual intersection arrival distance Db' is greater than the alarm distance Dth4.

[0215] In S1320, the controller 101a performs the notification issuance for the alarm.(Content of Notification Control in Straight Traveling Vehicle Traveling straight across Virtual Intersection)

[0216] Figs. 18 to 20 are flowcharts illustrating content of notification control performed by the controller 101b included in the straight traveling vehicle VB when the straight traveling vehicle VB travels straight across the intersection CS. The flowchart in Fig. 18 illustrates an overall flow of the notification control, the flowchart in Fig. 19 illustrates content of the information presentation processing executed by the straight traveling vehicle VB, and the flowchart in Fig. 20 illustrates content of the alarm processing executed by the straight traveling vehicle VB. The controller 101b performs the notification control every predetermined time. The execution cycles of the notification control may be the same or different between the controller 101a and the controller 101b. Furthermore, both the controllers 101a and 101b can also perform the notification control in a synchronized manner.

[0217] In the present embodiment, the controller 101b can process the aforementioned notification control for the straight traveling vehicle VB traveling straight across the intersection CS and the notification control for the straight traveling vehicle VB traveling straight across the virtual intersection VCS in parallel.

[0218] Each process performed by the controller 101a and the controller 101b in regard to the notification control at the virtual intersection VCS corresponds to each other. Therefore, detailed description of the processes that are similar for both will be omitted in the following description.

[0219] In the flowchart illustrated in Fig. 18, the controller 101b read various kinds of control information used for the notification control (S1411), detects another vehicle that is present in the right turn lane L11 in the opposite lanes, that is, the right turning vehicle VA (S1412), and then determines whether the right turn intention of the right turning vehicle VA, which is another vehicle, has been detected in S1413. After detecting the right turn intention, the controller 101b determines whether the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB is equal to or less than the predetermined separation distance Dth5 in S1414, determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the second predetermined vehicle speed VSP2 in a case where the distance Dab is equal to or less than the predetermined separation distance Dth5 (S1415). In a case where the vehicle speed VSPa is equal to or less than the second predetermined vehicle speed VSP2, the controller 101b sets the virtual intersection area VACS and the virtual predicted collision area VACP (S1416), specifies the current position Pa of the right turning vehicle VA on the road map (S1417), and determines whether the right turning vehicle VA has entered the virtual intersection area VACS (S1418). The controller 101b executes the procedure in and after S1419 in a case where the right turning vehicle VA has entered the virtual intersection area VACS, or ends this control in a case where the right turning vehicle VA has not entered the virtual intersection area VACS. The controller 101b executes the information presentation processing in S1419 and the alarm processing in S1420. The information presentation processing and the alarm processing are repeated until the right turning vehicle VA passes the virtual intersection area VACS. Note that it is also possible to eliminate the processing in S1414 and S1415 themselves, as S1114 and S1115 described above.

[0220] In the flowchart illustrated in Fig. 19, the controller 101b reads various kinds of control information used for the information presentation processing, such as the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA (S1511), and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map (S1512). In S1513, the controller 101b determines whether the right turning vehicle VA, which is another vehicle, is located outside the virtual predicted collision area VACP, reads the vehicle speed VSPa of the right turning vehicle VA (S1514) in a case where the controller 101b determines that the right turning vehicle VA is located outside the virtual predicted collision area VACP, and determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the predetermined vehicle speed VSP1 (S1515). The controller 101b performs the processing in and after S1516 in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, or ends the information presentation processing in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1. The controller 101b may determine whether the operation of the right turn signal is being continued in addition to the processing in S1513, and execute the processing in and after S1514 in a case where the operation of the right turn signal is being continued. Then, the controller 101b calculates the virtual intersection arrival distance Db' of the straight traveling vehicle VB, which is the host vehicle (S1516), reads the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) (S1517), and calculates the information presentation distance Dth3 (S1518). The processing proceeds to S1520 to issue a notification for information presentation in a case where the intersection arrival distance Db is equal to or less than the information presentation distance Dth3 (S1519), or the information presentation processing is ended in a case where the virtual intersection arrival distance Db' is greater than the information presentation distance Dth3.

[0221] In the flowchart illustrated in Fig. 20, the controller 101b reads various kinds of control information used for the alarm processing such as the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA (S1611), and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map are (S1612). The controller 101b determines whether the right turning vehicle VA, which is another vehicle, is located inside the virtual predicted collision area VACP, in S1613, reads the vehicle speed VSPa of the right turning vehicle VA (S1614) in a case where the right turning vehicle VA is determined not to be located inside the virtual predicted collision area VACP, and determines whether the vehicle speed VSPa of the right turning vehicle VA is greater than the predetermined vehicle speed VSP1 (S1615). The fact that the operation of the right turn signal, which is used to detect the right turn intention of the right turning vehicle VA, is being continued may be included as a condition of performing the processing as a premise of performing the processing in S1613. The controller 101b performs the processing in and after S1616 in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1, or ends the alarm processing in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. Then, the controller 101b calculates the virtual intersection arrival distance Db' of the straight traveling vehicle VB, which is a host vehicle (S1616), reads the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) (S1617), and calculates the alarm distance Dth4 (S1618). The processing proceeds to S1620 to issue a notification for the alarm in a case where the virtual intersection arrival distance Db' is equal to or less than the alarm distance Dth4, or the alarm processing is ended in a case where the virtual intersection arrival distance Db' is greater than the alarm distance Dth4.(Description of Actions and Effects)

[0222] The vehicle notification system 1 according to the present embodiment has the aforementioned configuration. Effects obtained by the present embodiment will be described below.

[0223] First, in a traffic situation where the right turning vehicle VA turning right at the intersection CS and the straight traveling vehicle VB traveling in the straight direction toward the intersection CS in the opposite lane L22 are present, the current position Pa of the right turning vehicle VA on the road map and the current position Pb of the straight traveling vehicle VB on the road map are specified. Then, notifications in different modes are issued under the condition that the notification issuance condition related to the distance Db of the straight traveling vehicle VB is established at each of a timing at which presence of the right turning vehicle VA at the first predetermined position P1 or a position closer to the intersection center CTR than the first predetermined position P1 is detected after the right turn intention of the right turning vehicle VA is detected and a timing at which the right turning vehicle VA is traveling toward the predicted collision point CPP at a position closer to the predicted collision point CPP than the first predetermined position P1 or enters to a position closer to the predicted collision point CPP than the second predetermined position P2. It is thus possible to realize a notification in an appropriate mode in accordance with the relative relationship between the right turning vehicle VA and the straight traveling vehicle VB.

[0224] Specifically, the notification in the first predetermined mode is issued to the traffic participants under the condition that the straight traveling vehicle VB is located at the first predetermined distance, that is, the information presentation distance Dth1 from the intersection CS or is present at a position closer to the intersection CS than the information presentation distance Dth1 at a timing at which the right turning vehicle VA is located at a position with a relatively long distance left to the predicted collision point CPP after the detection of the right turn intention. In the present embodiment, both the right turning vehicle VA and the straight traveling vehicle VB are considered the traffic participants as targets of notification issuance.

[0225] On the other hand, a notification in the second predetermined mode, which is different from the first predetermined mode, is issued to the traffic participants under the condition that the straight traveling vehicle VB is located at a position closer to the intersection CS, that is, at the second predetermined distance (alarm distance Dth2) from the intersection CS or is present at a position closer to the intersection CS than the alarm distance Dth2 in a case where the right turning vehicle VA is still continuing to travel even after passing the position of the first predetermined position P1 or has approached the position closer to the predicted collision point CPP.

[0226] In this manner, the notification issuance for the purpose of promoting recognition of the presence of the counterpart vehicle (the straight traveling vehicle VB for the right turning vehicle VA, for example), that is, the notification issuance for the information presentation is executed as the first predetermined mode, and the notification issuance for the purpose of promoting recognition of higher urgency, that is, the notification issuance for the alarm is executed as the second predetermined mode, in accordance with the relative positional relationship between the right turning vehicle VA and the straight traveling vehicle VB, for example.

[0227] Second, it is possible to promote the drivers to quickly and easily understand notification issuance and content thereof by issuing the notification using display and / or sound and differentiating the display or the sound between the first predetermined mode and the second predetermined mode.

[0228] Third, it is possible to easily determine the timing at which the notification issuance in the first predetermined mode and the notification issuance in the second predetermined mode are to be executed and to execute the notification issuance by the intersection area ACS and the predicted collision area ACP being set.

[0229] Fourth, it is possible to execute the notification issuance in each of the first and second predetermined modes at an appropriate timing that reflects the distance required to decelerate and brake the straight traveling vehicle VB by calculating the first and second predetermined distances (the information presentation distance Dth1 and the alarm distance Dth2) on the basis of the vehicle speed VSPb of the straight traveling vehicle VB.

[0230] Fifth, it is possible to execute the notification issuance in each of the first and second predetermined modes at a timing according to the behavior of the vehicle at the time of causing the brake to work by setting the deceleration degree DEC1 for calculating the information presentation distance and the deceleration degree DEC2 for calculating the alarm distance, which is higher than the deceleration degree DEC1, and calculating the first and second predetermined distances on the basis of the deceleration degrees DEC1 and DEC2 along with the vehicle speed VSPb of the straight traveling vehicle VB.

[0231] Sixth, it is possible to perform notification issuance in the first predetermined mode at a timing on the assumption of slower braking and to perform the notification issuance in the second predetermined mode at a timing on the assumption of sudden breaking by setting the deceleration degree DEC2 for calculating the alarm distance to be higher than the deceleration degree DEC1 for calculating the information presentation distance.

[0232] Seventh, it is possible to more appropriately calculate the timing at which the notification issuance for each of the information presentation and the alarm is actually performed such that a trend (a degree of slowness or suddenness, for example) of the braking operation that the driver actually performs is reflected, and it is possible to execute the notification issuance in each mode at a more appropriate timing, by learning the actual deceleration degree of the straight traveling vehicle VB for the notification issuance in the second predetermined mode and correcting the deceleration degrees DEC1 and DEC2 used to calculate each of the information presentation distance Dth1 and the alarm distance Dth2 on the basis of the thus obtained learning value.

[0233] Here, it is possible to avoid a situation in which the notification issuance is unnecessarily executed in a case where the display of entrance to the right turn lane L11 or the like is not based on the original right turn intention and the entrance is only temporarily made, by detecting the right turn intention in a case where the right turn intention displayed by the entrance to the right turn lane L11 or the operation of the right turn signal or the like continues for a predetermined period of time or more. In a case where another vehicle is stopping at a roadside of a road extending after the intersection CS or an obstacle installed on the road such as a sign is present, for example, lanes may be changed before or after the entrance to the intersection CS for the purpose of avoiding collision against the obstacle. The right turn intention is not detected in such a case, the right turning vehicle VA ends the control on the basis of negative determination in S113 illustrated in Fig. 4, and the straight traveling vehicle VB ends the control on the basis of negative determination in S413 illustrated in Fig. 7, to thereby avoid the unnecessary notification issuance.

[0234] In contrast, in a case of right turn based on the original right turn intention, the right turning vehicle VA has been decelerated before entering the intersection CS, and some period of time is secured before the entrance to the intersection CS after the display of the right turn intention. Therefore, there are no substantial adverse effects in the detection of the right turn intention even if the continued display of the right turn intention is used as the condition for detecting the right turn intention, and it is possible to appropriately detect that the right turning vehicle VA has the right turn intention.

[0235] In addition, it is possible to issue a notification with higher urgency with a higher priority and to promote the driver to accurately recognize the situation by prioritizing the notification issuance for the alarm than the notification issuance for the information presentation in a case where the notification issuance condition for the information presentation and the notification issuance condition for the alarm are established at the same time.

[0236] The traffic participants as targets of the notification issuance are not limited to the right turning vehicle VA and the straight traveling vehicle VB and may be any other vehicles that are approaching the intersection CS. It is possible to exemplify, as such vehicles, a vehicle traveling toward the intersection CS (hereinafter, referred to as a "crossing vehicle") in a lane other than the right turn lane L11 and lanes extending in parallel to the right turn lane L11 (for example, the straight lane L12), specifically, a lane intersecting the right turn lane L11 from among lanes leading to the intersection CS to which the right turning vehicle VA is directed. Here, a vehicle other than the right turning vehicle VA that is approaching an intersection CS and may enter the intersection CS is referred to as an "intersection-entering vehicle". The intersection-entering vehicles include the straight traveling vehicle VB and the crossing vehicle.

[0237] In the load R illustrated in Fig. 11, a traffic situation in which vehicles traveling toward the intersection CS include a crossing vehicle (not shown) in addition to the right turning vehicle VA and the straight traveling vehicle is assumed. In this situation, when a traffic signal to regulate passing of the crossing vehicle that enters the intersection CS is not installed, there is a concern that the timing at which the crossing vehicle enters the intersection CS and the timings at which the right turning vehicle VA and the straight traveling vehicle VB enter the intersection CS may become the same and these vehicles may be brought into contact with or collide against each other at the intersection CS.

[0238] In such a situation, the notification system 1 monitors the relative positional relationship between the right turning vehicle VA and the crossing vehicle in addition to or instead of the control related to the notification between the right turning vehicle VA and the straight traveling vehicle VB after detecting the right turn intention of the right turning vehicle VA. Then, similarly to the above description, the notification issuance in accordance with urgency of the situation related to contact or collision between the right turning vehicle VA and the crossing vehicle is executed at an appropriate timing before the right turning vehicle VA passes the intersection CS after approaching the intersection CS. For example, the right turning vehicle VA and the crossing vehicle perform information presentation processing and alarm processing similar to those performed between the right turning vehicle VA and the straight traveling vehicle VB.

[0239] Furthermore, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that regards the point at which the right turning path TRa' where the right turning vehicle VA travels when the right turning vehicle VA turns right at the virtual intersection VCS and enters the predetermined area PA located on the roadside along the opposite lane L22 of the road R and the center line CL of the road R intersect as the virtual intersection center VCTR, regards the point at which the right turning path TRa' and the straight traveling path TRb' of the straight traveling vehicle VB intersect as the virtual predicted collision point VCPP, and sets the virtual intersection area VACS including the virtual intersection center VCTR and the virtual predicted collision area VACP including the virtual predicted collision point VCPP in an associated manner on the road map in a case where the right turning vehicle VA and the straight traveling vehicle VB are present and the right turn intention of the right turning vehicle VA is detected. Therefore, the notification system 1 can perform the notification issuance in the third predetermined mode with an intention to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA under the condition that the third predetermined notification issuance condition defined in advance in regard to the position of the straight traveling vehicle VB is met at the third notification issuance timing set in accordance with the relative positional relationship between the virtual intersection area VACS and the right turning vehicle VA. In addition, the notification system 1 can perform the notification issuance in the fourth predetermined mode with an intention to provide an alarm to promote recognition of high urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA under the condition that the fourth notification issuance condition defined in advance in regard to the position of the straight traveling vehicle VB is met at the fourth notification issuance timing set in accordance with the positional relationship among the virtual intersection area VACS, the virtual predicted collision area VACP, and the right turning vehicle VA. Therefore, the notification system 1 can perform the notification issuance in an appropriate mode at an appropriate timing in accordance with a degree of urgency of the situation where there is a concern that the right turning vehicle VA and the straight traveling vehicle VB may collide against each other at a location other than the intersection CS of the road R.

[0240] Furthermore, the notification system 1 according to the present embodiment includes the first notification issuing unit B118a that does not perform the notification issuance in the third predetermined mode and the second notification issuing unit B119a that does not perform the notification issuance in the fourth predetermined mode in a case where the right turning vehicle VA enters the intersection area ACS that overlaps the path TRa where the right turning vehicle VA travels when the right turning vehicle VA turns right at and passes the intersection CS leading to the traveling lane L11. Therefore, the notification system 1 can distinguish the case of turning right at the intersection CS and the case of turning right at a location other than the intersection CS, that is, turning right at the virtual intersection VCS, and perform the notification issuance in an appropriate predetermined mode (the notification issuance in the first predetermined mode and the notification issuance in the second predetermined mode) when the right turning vehicle VA passes through the intersection CS in a case where the right turning vehicle VA actually passes the intersection CS even after the setting of the virtual intersection area VACS and the virtual predicted collision area VACP.

[0241] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that does not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB exceeds the predetermined separation distance Dth5. Therefore, the notification system 1 can reduce the calculation load by not setting the unnecessary virtual intersection area VACS and virtual predicted collision area VACP in a case where the distance between the right turning vehicle VA and the straight traveling vehicle VB is sufficiently long and the risk of collision between the right turning vehicle VA and the straight traveling vehicle VB is low. On the other hand, the notification system 1 can perform the notification in a predetermined mode with an appropriate positional relationship between the right turning vehicle VA and the straight traveling vehicle VB by setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance Dab is equal to or less than the predetermined separation distance Dth5.

[0242] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that does not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the vehicle speed VSPa of the right turning vehicle VA exceeds the second predetermined vehicle speed VSP2 that is higher than the first predetermined vehicle speed VSP1. Therefore, the notification system 1 can reduce the calculation load by not setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where it is determined that the right turning vehicle VA will not turn right. On the other hand, the notification system 1 can perform the notification in a predetermined mode with an appropriate positional relationship between the right turning vehicle VA and the straight traveling vehicle VB by setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the vehicle speed VSPa is equal to or less than the second predetermined vehicle speed VSP2.

[0243] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that sets the virtual intersection area VACS with the outer edge that includes the four vertices of the virtual intersection VCS. Therefore, the notification system 1 can more appropriately use the virtual intersection area VACS as a determination criterion for recognizing the relative positional relationship between the right turning vehicle VA and the virtual intersection VCS.

[0244] Furthermore, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that sets the virtual intersection area VACS such that the right turning vehicle VA is not present inside the virtual intersection area VACS and the outer edge of the virtual intersection area VACS is located just in front of the right turning vehicle VA. Therefore, the notification system 1 can more reliably perform the notification issuance in the third predetermined mode with an intention to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA and the notification issuance in the fourth predetermined mode with an intention to provide an alarm to promote recognition of high urgency as compared with a case where the virtual intersection area VACS is set so as to be located far away from the right turning vehicle VA on the front side.

[0245] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that sets the right turning path TRa' in an associated manner on the road map on the basis of at least one of the destination information of the navigation device 115a in which the predetermined area PA is set as a destination, the steering amount of the right turning vehicle VA detected by the steering angle sensor 114a as the steering amount detection section, and the vehicle speed VSPa of the right turning vehicle VA. Therefore, the notification system 1 can accurately set the right turning path TRa' and improve the setting accuracy of the virtual intersection area VACS and the virtual predicted collision area VACP that are set on the basis of the right turning path TRa'. In other words, the notification system 1 can accurately perform the notification issuance in a predetermined mode based on the virtual intersection area VACS and the virtual predicted collision area VACP.

[0246] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that determines the virtual intersection area VACS from among at least one virtual intersection area candidate VACSC, which is a candidate for the virtual intersection area VACS, and determines the virtual predicted collision area VACP from among at least one virtual predicted collision area candidate VACPC, which is a candidate for the virtual predicted collision area VACP, by determining the predetermined area PA from among at least one predetermined area candidate PAC, which is a candidate for the predetermined area PA. Therefore, the notification system 1 can shorten the setting processing time for the virtual intersection area VACS and the virtual predicted collision area VACP after the predetermined setting condition is met and can improve accuracy when the notification in a predetermined mode is performed by setting the virtual intersection area VACS and the virtual predicted collision area VACP with no delay.

[0247] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that determines the predetermined area PA from among at least one predetermined area candidate PAC on the basis of at least one of the steering amount of the right turning vehicle VA detected by the steering angle sensor 114a as the steering amount detection and notification section and the vehicle speed VSPa of the right turning vehicle VA. Therefore, the notification system 1 can set the virtual intersection area VACS and the virtual predicted collision area VACP without delay and with high accuracy, allowing for more precise notification in a predetermined mode.

[0248] In the above description, the distance from the outer edge of the predicted collision area ACP, specifically, the intersecting point between the traveling path TRb of the straight traveling vehicle VB and the circle (the circles illustrated by the dashed lines in Figs. 12 and 13) defining the outer edge of the predicted collision area ACP to the straight traveling vehicle VB is employed as the intersection arrival distance Db from the intersection CS to the straight traveling vehicle VB. The intersection arrival distance Db is not limited thereto, and the distance from the predicted collision point CPP to the straight traveling vehicle VB may be employed, or the distance along the center line of the opposite lane L22 from the right turning vehicle VA to the straight traveling vehicle VB may be employed, as the intersection arrival distance Db. In the same manner, the distance from the outer edge of the predicted collision area ACP, specifically, the intersecting point between the traveling path TRb' of the straight traveling vehicle VB and the circle (the circles illustrated by the dashed lines in Figs. 22 and 23) defining the outer edge of the virtual predicted collision area VACP to the straight traveling vehicle VB is employed as the virtual intersection arrival distance Db' from the virtual intersection VCS to the straight traveling vehicle VB. The virtual intersection arrival distance Db' is not limited thereto, and the distance from the virtual predicted collision point VCPP to the straight traveling vehicle VB may be employed, or the distance along the center line of the opposite lane L22 from the right turning vehicle VA to the straight traveling vehicle VB may be employed, as the virtual intersection arrival distance Db'. In addition, at the virtual intersection VCS having a regular square shape, the distance from the side of the virtual intersection VCS closer to the straight traveling vehicle VB to the straight traveling vehicle may be employed, as the virtual intersection arrival distance Db'.

[0249] Furthermore, although the controllers 101a and 101b included in the right turning vehicle VA and the straight traveling vehicle VB, respectively constitute the calculation unit of the notification system 1 and the controllers 101a and 101b constitute one virtual controller, a configuration in which roadside equipment or a remote server is caused to have the road map and a computer program for the notification control and is caused to perform the notification control outside the vehicles may also be adopted. In this case, the right turning vehicle VA and the straight traveling vehicle VB transmit position information of the respective vehicles to the external controller through road-to-vehicle communication and receive command signals which are results of calculation related to control. Then, the notification issuance for the information presentation or the alarm is executed on the basis of the command signals.

[0250] In the above description, a traffic situation where the right turning vehicle VA traveling toward a predetermined section of the left-hand traffic road R to turn right at the predetermined section and the straight traveling vehicle VB traveling in the straight traveling direction toward the predetermined section in the opposite lane L22 that is opposite to the traveling lane L11 where the right turning vehicle VA travels are present is assumed. Also, the notification system 1 that assumes the intersection CS as the predetermined section of the road R and the virtual intersection VCS that is a location other than the intersection and performs notification issuance to avoid collision between the right turning vehicle VA and the straight traveling vehicle VB when the right turning vehicle VA turns right in each case has been described. Here, the notification system 1 that performs the notification issuance at the virtual intersection VCS, which is a location other than the intersection CS, can actually be applied to the intersection CS as well. In other words, the notification system 1 can perform the notification issuance to avoid collision between the right turning vehicle VA and the straight traveling vehicle VB when the right turning vehicle VA turns right without distinguishing the intersection CS and the location other than the intersection CS, by including the intersection CS in the virtual intersection VCS.

[0251] In other words, the notification system 1 according to the preset embodiment is a vehicle notification system that issues notifications for traffic participants including a right turning vehicle VA that is present in a traveling lane L11 leading to a predetermined section on a road R in order to turn right at the predetermined section and a straight traveling vehicle VB that is traveling in a straight direction on a lane L22 opposite to the traveling lane L11 toward the predetermined section.

[0252] The notification system 1 includes: a road map storage unit B113a that stores a road map including the predetermined section and specifies a current position of the right turning vehicle VA on the road map and a current position of the straight traveling vehicle VB on the road map; and a right turn intention detection unit B114a that detects a right turn intention of the right turning vehicle VA.

[0253] The notification system 1 further includes a virtual area setting unit B122a that in a case where a specification result of the road map storage unit B113a shows that the right turning vehicle VA and the straight traveling vehicle VB are present and the right turn intention detection unit B114a detects the right turn intention, regards, as a virtual intersection center VCTR, a point at which a right turning path TRa' that is a path where the right turning vehicle VA travels when the right turning vehicle VA turns right at the predetermined section and a center line CL that sections the traveling lane L11 and the opposite lane L22 or extension of the center line CL intersect, regards, as a virtual predicted collision point VCPP, a point where the right turning path TRa' and a straight traveling path TRb' that is a path where the straight traveling vehicle VB travels intersect, and sets a virtual intersection area VACS including the virtual intersection center VCTR and a virtual predicted collision area VACP including the virtual predicted collision point VCPP in an associated manner in the road map.

[0254] The notification system 1 further includes: a third vehicle behavior detection unit B120a that sets, as a third notification issuance timing, a timing at which presence of the right turning vehicle VA at a predetermined position relative to the virtual intersection area VACS set by the virtual area setting unit B122a is detected on the basis of the current position of the right turning vehicle VA specified by the road map storage unit; and a fourth vehicle behavior detection unit B121a that sets, as a fourth notification issuance timing that is different from the third notification issuance timing, a timing at which traveling of the right turning vehicle VA toward the virtual predicted collision point VCPP inside the virtual intersection area VACS or presence of the right turning vehicle VA inside the virtual predicted collision area VACP is detected after the third vehicle behavior detection unit B120a sets the third notification issuance timing.

[0255] The notification system 1 further includes: a first notification issuing unit B118a that performs notification issuance in a third predetermined mode for the traffic participants under a condition that a third predetermined notification issuance condition defined in advance in regard to a position of the straight traveling vehicle VB is met at the third notification issuance timing set by the third vehicle behavior detection unit B120a; and a second notification issuing unit B119a that performs notification issuance in a fourth predetermined mode for the traffic participants under a condition that a fourth predetermined notification issuance condition defined in advance in regard to the position of the straight traveling vehicle VB is met at the fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a.

[0256] While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions, and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.REFERENCE SIGNS LIST

[0257] 1Vehicle notification system 101a, 101bController 111a, 111bPosition sensor 112a, 112bVehicle speed sensor 113a, 113bRight turn signal switch 114a, 114bSteering angle sensor 115a, 115bnavigation device 121a, 121bTransmitter 122a, 122bReceiver 131a, 131bHMI device

Examples

Embodiment Construction

[0014]Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the same reference signs are given to identical or equivalent components in each figure.

(Overall Configuration of Vehicle Notification System)

[0015]Fig. 1 is a schematic diagram illustrating a configuration of a vehicle notification system (hereinafter, simply referred to as a "notification system" in some cases) 1 according to an embodiment of the present invention.

[0016] In the present embodiment, a traffic situation where a vehicle (hereinafter, referred to as a "right turning vehicle") VA traveling toward a predetermined section (predetermined location) on a left-hand traffic road in order to turn right at the predetermined section and another vehicle (hereinafter, referred to as a "straight traveling vehicle") VB traveling in a straight direction toward the predetermined section in a lane (hereinafter, referred to as an "opposite lane" in some cases) opposite to a...

BACKGROUND OF THE INVENTIONField of the Invention

[0001] Embodiments of the present invention relate to a vehicle notification system.Description of the Related Art

[0002] For the purpose of assisting driving in situations where right turn is made at intersections on left-hand traffic roads, there is a technology of recognizing operation statuses of other traffic participants including oncoming vehicles moving straight ahead toward intersections in opposite lanes and providing an instruction for a right turn timing that allows a driver to avoid collisions against the oncoming vehicles to the driver.

[0003] Here, detection of traffic participants is typically performed by in-vehicle sensors such as cameras or radars.

[0004] [Patent Document 1] JP 2009-265832 A

[0005] However, it is difficult for in-vehicle sensors to detect traffic participants who are present at blind angles such as behind obstacles.

[0006] Specifically, in a case where there is another vehicle traveling side by side with an oncoming vehicle in the same lane, or in a case where another vehicle is stopping to wait for turning right in front of the oncoming vehicle, the vehicle may become an obstacle, and the oncoming vehicle may be present at a blind angle of the vehicle, which may make it difficult to detect the oncoming vehicle depending on an in-vehicle sensor equipped in the right turning vehicle.

[0007] In a case where the vehicle that may become an obstacle is a large vehicle, the blind angle becomes wider, which makes it more difficult to detect the oncoming vehicle.

[0008] Moreover, a situation where a right turning vehicle and a straight traveling vehicle, which is an oncoming vehicle thereto, are present is not necessarily limited to an intersection. A case of a two-way road in which a straight traveling vehicle advances straight in an opposite lane and a right turning vehicle turns right into a store such as a convenience store or a residential property located on a roadside along the opposite lane, for example, is assumed. In this case, driving assistance is needed in a situation in which the right turning vehicle turns right at a location other than an intersection of the road, that is, the right turning vehicle crosses the opposite lane.SUMMARY OF THE INVENTION

[0009] Thus, an object of the present invention is to provide a vehicle notification system that can assist driving even in situations of turning right at a location other than intersections of roads and contribute to a further improvement in traffic safety.

[0010] To achieve the above-mentioned object, a vehicle notification system issues notifications for traffic participants including a first vehicle that is present in a traveling lane leading to a predetermined section on a road in order to turn right or left at the predetermined section and a second vehicle that is traveling in a straight direction on a lane opposite to the traveling lane toward the predetermined section. The vehicle notification system includes: a road map storage unit that stores a road map including the predetermined section and specifies a current position of the first vehicle on the road map and a current position of the second vehicle on the road map; a direction-change-intention detection unit that detects a direction change intention of the first vehicle turning right or left at the predetermined section; a virtual area setting unit that in a case where a specification result of the road map storage unit shows that the first vehicle and the second vehicle are present and the direction-change-intention detection unit detects the direction change intention, regards, as a virtual intersection center, a point at which a turning path that is a path where the first vehicle travels when the first vehicle turns right or left at the predetermined section and enters a predetermined area located on a roadside along the opposite lane of the road and a center line that sections the traveling lane and the opposite lane intersect, regards, as a virtual predicted collision point, a point where the turning path and a straight traveling path that is a path where the second vehicle travels intersect, and sets a virtual intersection area including the virtual intersection center and a virtual predicted collision area including the virtual predicted collision point in an associated manner in the road map; a third vehicle behavior detection unit that sets, as a third notification issuance timing, a timing at which presence of the first vehicle at a predetermined position relative to the virtual intersection area set by the virtual area setting unit is detected on the basis of the current position of the first vehicle specified by the road map storage unit; a fourth vehicle behavior detection unit that sets, as a fourth notification issuance timing that is different from the third notification issuance timing, a timing at which traveling of the first vehicle toward the virtual predicted collision point inside the virtual intersection area or presence of the first vehicle inside the virtual predicted collision area is detected after the third vehicle behavior detection unit sets the third notification issuance timing; a first notification issuing unit that performs notification issuance in a third predetermined mode for the traffic participants under a condition that a third predetermined notification issuance condition defined in advance in regard to a position of the second vehicle is met at the third notification issuance timing set by the third vehicle behavior detection unit; and a second notification issuing unit that performs notification issuance in a fourth predetermined mode for the traffic participants under a condition that a fourth predetermined notification issuance condition defined in advance in regard to the position of the second vehicle is met at the fourth notification issuance timing set by the fourth vehicle behavior detection unit.

[0011] To achieve the above-mentioned object, a vehicle notification system performs notification issuance for traffic participants including a first vehicle and a second vehicle traveling in a lane opposite to a lane where the first vehicle is traveling in a traffic situation where the first vehicle and the second vehicle are present. The vehicle notification system includes: a road map storage unit that stores a road map; a first vehicle position specification unit that specifies a current position of the first vehicle on the road map; a second vehicle position specification unit that specifies a current position of the second vehicle on the road map; a direction-change-intention detection unit that detects a direction change intention of the first vehicle turning right or left; a virtual area setting unit that sets a virtual area that overlaps a path where the first vehicle travels when the first vehicle turns right or left on the road map corresponding to a section between the first vehicle and the second vehicle in a case where the direction-change-intention detection unit detects the direction change intention; a notification issuance timing setting unit that sets a notification issuance timing in accordance with a position of the first vehicle relative to the virtual area set by the virtual area setting unit; and a notification issuing unit that performs notification issuance in a predetermined mode for the traffic participants under a condition that a predetermined notification issuance condition defined in regard to a position of the second vehicle is met at the notification issuance timing set by the notification issuance timing setting unit.EFFECTS OF THE INVENTION

[0012] According to one aspect of the present invention, it is possible to provide a vehicle notification system that can assist driving even in situations of turning right at a location other than intersections of roads and contribute to a further improvement in traffic safety.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Fig. 1 is a schematic diagram illustrating an overall configuration of a vehicle notification system according to an embodiment of the present invention; Fig. 2 is a schematic diagram illustrating an internal configuration of a controller included in a right turning vehicle; Fig. 3 is a schematic diagram illustrating an internal configuration of a controller included in a straight traveling vehicle; Fig. 4 is a flowchart illustrating an overall flow of notification control performed in the right turning vehicle that turns right at an intersection; Fig. 5 is a flowchart illustrating content of the notification control (information presentation processing) performed in the right turning vehicle that turns right at the intersection; Fig. 6 is a flowchart illustrating content of the notification control (alarm processing) performed in the right turning vehicle that turns right at the intersection; Fig. 7 is a flowchart illustrating an overall flow of notification control performed in the straight traveling vehicle that travels straight across the intersection; Fig. 8 is a flowchart illustrating content of the notification control (information presentation processing) performed in the straight traveling vehicle that travels straight across the intersection; Fig. 9 is a flowchart illustrating content of the notification control (alarm processing) performed in the straight traveling vehicle that travels straight across the intersection; Fig. 10 is an explanatory diagram illustrating a method of calculating an information presentation distance and an alarm distance; Fig. 11 is a schematic diagram illustrating an example of a traffic situation at the intersection, the traffic situation being assumed to be a target of a notification; Fig. 12 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an information presentation issuance timing at the intersection; Fig. 13 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an alarm issuance timing at the intersection; Fig. 14 is a schematic diagram illustrating a situation at the intersection after the straight traveling vehicle passes the intersection; Fig. 15 is a flowchart illustrating an overall flow of notification control performed in the right turning vehicle that turns right at a virtual intersection; Fig. 16 is a flowchart illustrating content of the notification control (information presentation processing) performed in the right turning vehicle that turns right at the virtual intersection; Fig. 17 is a flowchart illustrating content of the notification control (alarm processing) performed in the right turning vehicle that turns right at the virtual intersection; Fig. 18 is a flowchart illustrating an overall flow of notification control performed in the straight traveling vehicle that travels straight across the virtual intersection; Fig. 19 is a flowchart illustrating content of the notification control (information presentation processing) performed in the straight traveling vehicle that travels straight across the virtual intersection; Fig. 20 is a flowchart illustrating content of the notification control (alarm processing) performed in the straight traveling vehicle that travels straight across the virtual intersection; Fig. 21 is a schematic diagram illustrating an example of a traffic situation at the virtual intersection, the traffic situation being assumed to be a target of a notification; Fig. 22 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an information presentation issuance timing at the virtual intersection; Fig. 23 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an alarm issuance timing at the virtual intersection; Fig. 24 is a schematic diagram illustrating a situation after the straight traveling vehicle passes the virtual intersection; Fig. 25 is a schematic diagram illustrating a right turning path of the right turning vehicle set by a virtual area setting unit; and Fig. 26 is a schematic diagram illustrating virtual intersection area candidates and virtual predicted collision area candidates generated by the virtual area setting unit. DETAILED DESCRIPTION

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the same reference signs are given to identical or equivalent components in each figure.(Overall Configuration of Vehicle Notification System)

[0015] Fig. 1 is a schematic diagram illustrating a configuration of a vehicle notification system (hereinafter, simply referred to as a "notification system" in some cases) 1 according to an embodiment of the present invention.

[0016] In the present embodiment, a traffic situation where a vehicle (hereinafter, referred to as a "right turning vehicle") VA traveling toward a predetermined section (predetermined location) on a left-hand traffic road in order to turn right at the predetermined section and another vehicle (hereinafter, referred to as a "straight traveling vehicle") VB traveling in a straight direction toward the predetermined section in a lane (hereinafter, referred to as an "opposite lane" in some cases) opposite to a lane (hereinafter, referred to as a "traveling lane" in some cases) in which the right turning vehicle VA is traveling are present is assumed. The notification system 1 can be applied not only to left-hand traffic roads but also to right-hand traffic roads. In a case of right-hand traffic, a traffic situation where a left turning vehicle traveling in a traveling lane toward a predetermined section and a straight traveling vehicle traveling toward the predetermined section in an opposite lane are present is assumed to be a target. In other words, the notification system 1 can be applied to traffic situations where a right or left turning vehicle (hereinafter, referred to as a "right or left turning vehicle" or a "non-straight traveling vehicle") in a traveling lane and a straight traveling vehicle in an opposite lane are present together. In a case of left-hand traffic, the right turning vehicle is a vehicle turning right at the predetermined section and should not hinder the straight traveling vehicle traveling in the opposite lane from passing the predetermined section.

[0017] In the present embodiment, both intersections and locations other than intersections are assumed as predetermined sections of roads. For convenience of the following explanation, locations other than intersections may be regarded as virtual intersections and may be referred to as "virtual intersections" below.

[0018] As illustrated in Fig. 1, the notification system 1 includes, as main elements related to the present embodiment, auxiliary devices such as vehicle sensors 111 to 113, communication devices 121 and 122, and a human machine interface (HMI) device 131 in addition to a controller 101.

[0019] In the present embodiment, various elements including the controller 101 are provided in each of the right turning vehicle VA and the straight traveling vehicle VB. A controller 101a included in the right turning vehicle VA and a controller 101b included in the straight traveling vehicle VB configure one virtual controller constituting the notification system 1 through mutual cooperation. It is a matter of course that the notification system 1 can be configured as an in-vehicle system for the right turning vehicle VA by the controller 101a included in the right turning vehicle VA and the auxiliary devices thereof and can also be configured as an in-vehicle system for the straight traveling vehicle VB by the controller 101b included in the straight traveling vehicle VB and the auxiliary devices thereof.

[0020] In the following description, vehicle-to-vehicle communication is performed between the right turning vehicle VA and the straight traveling vehicle VB to allow vehicle information related to the right turning vehicle VA to be shared between the right turning vehicle VA and the straight traveling vehicle VB and allow vehicle information related to the straight traveling vehicle VB to be shared between both the vehicles VA and VB. In the present embodiment, the vehicle information to be communicated or shared between the right turning vehicle VA and the straight traveling vehicle VB includes current positions Pa and Pb, vehicle speeds VSPa and VSPb, operating statuses of right turn signals (that is, outputs of right turn signal switches), and lane IDs of the vehicles VA and VB. The vehicle information to be communicated or shared between the right turning vehicle VA and the straight traveling vehicle VB may include destination information and a steering amount for each of the vehicles VA and VB. The communication between the right turning vehicle VA and the straight traveling vehicle VB is not limited to direct communication via vehicle-to-vehicle communication and may also be performed indirectly through roadside equipment installed at roadsides, servers disposed remotely, communication devices included in vehicles other than the right turning vehicle VA and the straight traveling vehicle VB.

[0021] In the present embodiment, the right turning vehicle VA and the straight traveling vehicle VB constitute the notification system 1 with similar basic configurations. The right turning vehicle VA includes the controller 101a and also includes vehicle sensors 111a, 112a, and 113a, communication devices 121a and 122a, and an HMI device 131a. On the other hand, the straight traveling vehicle VB includes the controller 101b and also includes vehicle sensors 111b, 112b, and 113b, communication devices 121b and 122b, and an HMI device 131b.

[0022] The right turning vehicle VA and the straight traveling vehicle VB include steering angle sensors 114a and 114b, and navigation devices 115a and 115b.

[0023] The controllers 101a and 101b constitute a calculation unit of the notification system 1 and generate and output a command signal in accordance with results of calculation. The controllers 101a and 101b are configured of microcomputers including central processing units (CPUs), storage devices such as ROMs and RAMs, and input / output interfaces.

[0024] The vehicle sensors 111a to 113a and 111b to 113b constitute a detection unit of the notification system 1. The right turning vehicle VA includes a position sensor 111a, a vehicle speed sensor 112a, and a right turn signal switch 113a as the accompanying vehicle sensors, while the straight traveling vehicle VB includes a position sensor 111b, a vehicle speed sensor 112b, and a right turn signal switch 113b as the accompanying vehicle sensors.

[0025] The position sensor 111a detects the current position Pa of the right turning vehicle VA, and the position sensor 111b detects the current position Pb of the straight traveling vehicle VB. Both the position sensors 111a and 111b can be configured of global navigation satellite system (GNSS) receivers and detect the current positions of the target vehicles VA and VB with latitude and longitude coordinates Pa (Pai, Paj) and Pb (Pbi, Pbj).

[0026] The vehicle speed sensor 112a detects the traveling speed (hereinafter, referred to as a "vehicle speed") VSPa of the right turning vehicle VA, while the vehicle speed sensor 112b detects the vehicle speed VSPb of the straight traveling vehicle VB. The vehicle speed sensors 112a and 112b can perform the detection by detecting wheel speeds (for example, rotation speeds of driven wheels) of the target vehicles VA and VB and converting the wheel speeds into traveling distances per unit time using tire dynamic radii or the like.

[0027] The right turn signal switch 113a outputs an on signal when a right direction indicator (hereinafter, referred to as a "right turn signal") included in the right turning vehicle VA is activated, and the right turn signal switch 113b outputs an on signal when the right turn signal included in the straight traveling vehicle VB is activated. The operations of the right turn signal switches 113a and 113b indicate that the target vehicles VA and VB intend to turn right on the road or change lanes.

[0028] Detection signals from the position sensor 111a, the vehicle speed sensor 112a, and the right turn signal switch 113a of the right turning vehicle VA are output to the controller 101a of the right turning vehicle VA, while detection signals from the position sensor 111b, the vehicle speed sensor 112b, and the right turn signal switch 113b of the straight traveling vehicle VB are output to the controller 101b of the straight traveling vehicle VB.

[0029] The HMI devices 131a and 131b constitute an output unit of the notification system 1. The HMI device 131a receives a command signal from the controller 101a and provides a notification related to a traffic situation to a driver of the right turning vehicle VA. The HMI device 131b receives a command signal from the controller 101b and provides a notification related to the traffic situation to a driver of the straight traveling vehicle VB.

[0030] The notifications may be provided by the HMI devices 131a and 131b visually or auditorily. The HMI devices 131a and 131b can provide both display and sound notifications and can also provide notifications using one of them. The HMI devices 131a and 131b are disposed at locations that allow the drivers to easily view the HMI devices 131a and 131b, such as on dashboards in the vehicles.

[0031] The steering angle sensors 114a and 114b detect angles at which wheels involved in steering, typically front wheels of the vehicles VA and VB are directed, that is, wheel direction angles (hereinafter, referred to as "steering angles"). The steering angles are angles formed between vertical planes perpendicular to rotation axes of the front wheels and vertical planes extending in the front-rear directions of the vehicles VA and VB. It is possible to acquire situations of steering and steering information of the vehicles VA and VB by the steering angle sensors 116a and 116b.

[0032] The navigation devices 115a and 115b guide route to destinations set by the drivers, on the basis of the current positions Pa and Pb of the vehicles VA and VB input from the position sensors 111a and 111b and the map information. The route guidance is performed by displaying maps, traveling routes, the current positions Pa and Pb of the vehicles VA and VB, and traveling directions on HMI devices 131a and 131b, for example. The traveling directions indicated in the route guidance include traveling straight, turning right, and turning left.

[0033] In addition to the above, the right turning vehicle VA includes a transmitter 121a and a receiver 122a, while the straight traveling vehicle VB includes a transmitter 121b and a receiver 122b. The transmitter 121a and the receiver 122a included in the right turning vehicle VA constitute a vehicle-to-vehicle communication device of the right turning vehicle VA, while the transmitter 121b and the receiver 122b included in the straight traveling vehicle VB constitute a vehicle-to-vehicle communication device of the straight traveling vehicle VB. The right turning vehicle VA and the straight traveling vehicle VB can perform wireless communication via the mutual vehicle-to-vehicle communication devices.

[0034] As mentioned earlier, the communication between the right turning vehicle VA and the straight traveling vehicle VB is not limited to direct communication between the right turning vehicle VA and the straight traveling vehicle VB and may also be indirect communication via roadside equipment, remote servers, other vehicles, or the like.

[0035] Hereinafter, traffic situations assumed in the present embodiments will be described, divided into a case of the intersections and a case of the virtual intersection.

[0036] Fig. 11 is a schematic diagram illustrating an example of a traffic situation at the intersection, the traffic situation being assumed to be a notification target according to the present embodiments.

[0037] In the present embodiment, a traffic situation in which the right turning vehicle VA and the straight traveling vehicle VB face each other with an intersection CS interposed therebetween is assumed. The intersection (a cross intersection in the present embodiment) CS is present on a road R with two lanes on each side including right turn lanes L11 and L21 and straight lanes L12 and L22. The right turning vehicle VA is present in the right turn lane L11 on one side and is approaching the intersection CS, while the straight traveling vehicle VB is present in the straight lane L22 on the other side and is traveling at a position separated from the intersection CS in a straight direction toward the intersection CS. Here, the right turn lane L11 corresponds to the traveling lane of the right turning vehicle VA, and the right turn lane L21 and the straight lane L22 correspond to lanes opposite to the right turning vehicle VA. The right turn lane L21 and the straight lane L22 as the opposite lanes may be referred to as an "opposite right turn lane" and an "opposite straight lane" below.

[0038] In addition to the right turning vehicle VA and the straight traveling vehicle VB, a vehicle (hereinafter, referred to as a "waiting vehicle") VC stopping to wait for turning right is present before a stop line SL2 in front of the straight traveling vehicle VB in the opposite right turn lane L21. In the illustrated traffic situation, the waiting vehicle VC is a visual obstacle blocking a part of a view from the right turning vehicle VA and blocking a part of a view from the straight traveling vehicle VB. In this situation, it is difficult to visually recognize the straight traveling vehicle VB from the right turning vehicle VA due to the straight traveling vehicle VB being present at a blind angle of the waiting vehicle VC seen from the right turning vehicle VA, and it is difficult to visually recognize the right turning vehicle VA from the straight traveling vehicle VB due to the right turning vehicle VA being present at a blind angle of the waiting vehicle VC seen from the straight traveling vehicle VB.

[0039] In such a situation, the notification system 1 monitors a relative positional relationship between the right turning vehicle VA and the straight traveling vehicle VB after the right turning vehicle VA displays its intention to turn right at the intersection CS (hereinafter simply referred to as a "right turn intention"). Then, the notification system 1 issues a notification in accordance with a degree of urgency of circumstances related to contact or collision between the right turning vehicle VA and the straight traveling vehicle VB at an appropriate timing after the right turning vehicle VA approaches the intersection CS and before the right turning vehicle VA passes the intersection CS.

[0040] Fig. 21 is a schematic diagram illustrating an example of a traffic situation at the virtual intersection, the traffic situation being assumed to be a notification target according to the present embodiments.

[0041] As illustrated in Fig. 21, a traffic situation where the right turning vehicle VA and the straight traveling vehicle VB face each other across a virtual intersection VCS, which is a location on the road R other than the intersection CS, will be further assumed in the present embodiment. The virtual intersection VCS is present on the road R with two lanes on each side including lanes L11, L12, L21, and L22. The right turning vehicle VA is present in the lane L11 and is approaching the virtual intersection VCS, while the straight traveling vehicle VB is present in the lane L22 and is traveling at a position separated from the virtual intersection VCS in a straight direction toward the virtual intersection VCS. It is assumed that the right turning vehicle VA turns right within the virtual intersection VCS and enters a predetermined area PA located on a roadside along the lane L22 of the road R. Here, the lane L11 corresponds to the traveling lane of the right turning vehicle VA, and the lanes L21 and L22 correspond to lanes opposite to the right turning vehicle VA. The lanes L21 and L22, which are opposite lanes, may be referred to as "opposite lanes" below. Among the traveling lanes, the lane L11 is the lane closest to the center line CL of the road R.

[0042] In addition to the right turning vehicle VA and the straight traveling vehicle VB, there is a waiting vehicle VC that is stopping to turn right to enter a predetermined area PA' located on a roadside along the lane L12 of the road R near the virtual intersection VCS in front of the straight traveling vehicle VB in the opposite lane L21. In the illustrated traffic situation, the waiting vehicle VC is a visual obstacle blocking a part of a view from the right turning vehicle VA and blocking a part of a view from the straight traveling vehicle VB. It is difficult to visually recognize the straight traveling vehicle VB from the right turning vehicle VA due to the straight traveling vehicle VB being present at a blind angle of the waiting vehicle VC seen from the right turning vehicle VA, and it is difficult to visually recognize the right turning vehicle VA from the straight traveling vehicle VB due to the right turning vehicle VA being present at a blind angle of the waiting vehicle VC seen from the straight traveling vehicle VB in this situation.

[0043] The notification system 1 monitors a relative positional relationship between the right turning vehicle VA and the straight traveling vehicle VB after the right turning vehicle VA displays its intention to turn right in the same manner as at the intersection CS, even at the virtual intersection VCS. Then, the notification system 1 issues a notification in accordance with a degree of urgency of circumstances related to contact or collision between the right turning vehicle VA and the straight traveling vehicle VB at an appropriate timing after the right turning vehicle VA approaches the virtual intersection VCS and before the right turning vehicle VA passes the virtual intersection VCS.

[0044] Note that in the present embodiment, a square section that overlaps a right turning path TRa', which is a path where the right turning vehicle VA travels when the right turning vehicle VA turns right and enters the predetermined area PA, and has a side corresponding to a road width W of the road R is assumed as the virtual intersection VCS. Furthermore, when a point where the right turning path TRa' intersects the center line CL that sections the traveling lanes L11 and L12 and the opposite lanes L21 and L22 is defined as a center position (hereinafter, referred to as a "virtual intersection center") VCTR of the virtual intersection VCS, it is assumed that the virtual intersection VCS is arranged such that the virtual intersection center VCTR is located on a virtual line segment VLS that passes through the center of the two sides of the virtual intersection VCS that are perpendicular to a road width direction of the road R.(Internal Configuration of Controller)

[0045] Fig. 2 is a schematic diagram illustrating an internal configuration of the controller 101a included in the right turning vehicle VA, and Fig. 3 is a schematic diagram illustrating an internal configuration of the controller 101b included in the straight traveling vehicle VB. The internal configuration of each of the controllers 101a and 101b will be described in turn on the basis of Figs. 2 and 3 and with reference to Figs. 11 and 12 as needed.

[0046] As illustrated in Fig. 2, the controller 101a of the right turning vehicle VA includes a host vehicle position detection unit B111a, an other vehicle position detection unit B112a, a road map storage unit B113a, a right turn intention detection unit B114a, a vehicle speed detection unit B115a, a first vehicle behavior detection unit B116a, a second vehicle behavior detection unit B117a, a first notification issuing unit B118a, a second notification issuing unit B119a, a third vehicle behavior detection unit B120a, a fourth vehicle behavior detection unit B121a, and a virtual area setting unit B122a. A function of each of these units B111a to B122a is realized in a software manner by the central processing unit included in the controller 101a reading a computer program stored in the storage device and operating in accordance with instructions of the program. In the present embodiment, the first vehicle behavior detection unit B116a and the second vehicle behavior detection unit B117a mainly function when the right turning vehicle VA turns right at the intersection CS, while the third vehicle behavior detection unit B120a, the fourth vehicle behavior detection unit B121a, and the virtual area setting unit B122a mainly function when the right turning vehicle VA turns right at the virtual intersection VCS, among the components B111a to B122a included in the controller 101a. The other components B111a to B115a, B118a, and B119a function in both a case where the right turning vehicle VA turns right at the intersection CS and a case where the right turning vehicle VA turns right at the virtual intersection VCS.

[0047] Note that data held by each of the components B111a to B122a and results of processing performed by each of the components B111a to B122a can be mutually referenced among the components B111a to B122a regardless of the presence or absence of arrows indicating a data flow inside the controller 101a in Fig. 2. The data held by each of the components B111a to B122a includes detection signals from the vehicle sensors 111a, 112a, and 113a and the steering angle sensor 114a output to the controller 101a, destination information set by the navigation device 115a, and vehicle information acquired from the straight traveling vehicle VB via the receiver 122a. These premises in the controller 101a are also applicable to the controller 101b of the straight traveling vehicle VB.

[0048] The host vehicle position detection unit B111a detects the current position Pa of the right turning vehicle VA, which is a host vehicle. The detection of the current position Pa performed by the host vehicle position detection unit B111a is based on an output signal from the position sensor 111a included in the right turning vehicle VA.

[0049] The other vehicle position detection unit B112a detects the current position Pb of the straight traveling vehicle VB, which is another vehicle. The detection of the current positions Pb performed by the other vehicle position detection unit B112a is performed by reading position information indicating the current position Pb from vehicle information acquired from the straight traveling vehicle VB via the receiver 122a included in the right turning vehicle VA.

[0050] The road map storage unit B113a stores a road map. In the present embodiment, the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB are coordinates of latitudes and longitudes indicating these positions Pa and Pb. The road map storage unit B113a extracts a map of a range or a section including the intersection CS in the road map and specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map. The map in the range or the section including the intersection CS extracted by the road map storage unit B113a is used when the right turning vehicle VA turns right at the intersection CS. The road map storage unit B113a extracts a map in a specific range or a specific section in the road map and specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map. The map in the specific range or the specific section extracted by the road map storage unit B113a is used when the right turning vehicle VA turns right at the virtual intersection VCS. The map in the specific range or the specific section may include the intersection CS or may not include the intersection CS. In the road map, identifiers (hereinafter, referred to as "link IDs") corresponding to lanes leading to at least one of the intersection CS and the virtual intersection VCS, such as the lanes L11, L21, L12, and L22, are assigned and are stored so as to correspond to the lanes L11, L21, L12, and L22. It is possible to distinguish the lane in which a target vehicle is present or is traveling by specifying the position thereof on the road map.

[0051] The road map includes, for example, position information of roadside buildings RB that include stores, facilities, and residences located on the roadsides along the road R. In the present embodiment, a roadside building RB that has a site where the right turning vehicle VA enters by turning right at the virtual intersection VCS among the roadside buildings RB may be referred to as the predetermined area PA including the site. Furthermore, the road map includes, for example, position information of a median strip provided to separate the traveling lanes L11 and L12 from the opposite lanes L21 and L22. Therefore, the map in the range or the section including the intersection CS or the map in the specific range or the specific section extracted by the road map storage unit B113a may include the position information of the roadside building RB and / or the median strip.

[0052] The right turn intention detection unit B114a detects that the right turning vehicle VA has a right turn intention. The right turn intention detection by the right turn intention detection unit B114a can be performed with an output signal from the right turn signal switch 113a included in the right turning vehicle VA, and in a case where the right turn lane L11 near the intersection CS is a lane only for right turn, the detection can also be performed by reading the link ID associated with the lane where the vehicle is traveling from the road map and detecting that the right turning vehicle VA is present in the right turn lane L11.

[0053] The vehicle speed detection unit B115a detects the vehicle speed VSPb of the straight traveling vehicle VB. The vehicle speed detection unit B115a detects the vehicle speed VSPb of the straight traveling vehicle VB (that is, another vehicle) by reading vehicle speed information indicating the vehicle speed VSPb from the vehicle information acquired from the straight traveling vehicle VB via the receiver 122a included in the right turning vehicle VA.

[0054] The first vehicle behavior detection unit B116a detects that the right turning vehicle VA is present at a first predetermined position P1 in the lane (that is, the right turn lane L11) where the right turning vehicle VA is traveling or at a position closer to a center position (hereinafter, referred to as an "intersection center") CTR of the intersection CS than the first predetermined position P1 after the right turn intention detection unit B114a detects the right turn intention on the basis of the current position Pa of the right turning vehicle VA on the road map, in other words, after the right turning vehicle VA displays its right turn intention by entering the right turn lane L11 or operating the right turn signal.

[0055] Fig. 12 is a schematic diagram illustrating a positional relationship between the right turning vehicle VA and the straight traveling vehicle VB at a timing when the right turning vehicle VA exceeds the stop line SL1 in the right turn lane L11 and enters the intersection CS. Fig. 12 illustrates only the right turn lane L11 and the straight lane L22 in the road R with two lanes on each side by simplifying the illustration of the road R (the same applies to Figs. 13 and 14, which will be described later).

[0056] In the present embodiment, an intersection area ACS is set as a determination criterion to recognize a relative positional relationship between the right turning vehicle VA and the intersection CS in a case where the right turning vehicle VA turns right at the intersection CS. The intersection area ACS is set to overlap a path TRa along which the right turning vehicle VA travels when passing the intersection CS, and the presence of the right turning vehicle VA at the first predetermined position P1 in the right turn lane L11 or the position closer to the intersection center CTR than the first predetermined position P1 is detected by arrival of the right turning vehicle VA at the intersection area ACS or entrance thereof into the intersection area ACS after displaying its right turn intention. The first vehicle behavior detection unit B116a sets the timing at which the right turning vehicle VA reaches the intersection area ACS or enters the intersection area ACS as a first notification issuance timing. The first notification issuance timing set by the first vehicle behavior detection unit B116a is a timing at which notification issuance in a first predetermined mode is performed in the right turning vehicle VA. The intersection area ACS is set as a circular area that includes the first predetermined position P1 on its outer edge concentrically with the intersection center CTR. Figs. 12 to 14 illustrate the intersection area ACS by two-dotted chain lines, illustrate the traveling path TRa of the right turning vehicle VA by one-dotted chain lines, and illustrate a predicted collision area ACP and a traveling path TRb of the straight traveling vehicle VB, which will be described later, by dashed lines and one-dotted chain lines, respectively.

[0057] The second vehicle behavior detection unit B117a regards, as a "predicted collision point" CPP, a point at which the path TRa along which the right turning vehicle VA travels when passing the intersection CS and the path TRb along which the straight traveling vehicle VB travels when passing the intersection CS intersect and detects, on the basis of the current position Pa of the right turning vehicle VA on the road map, that the right turning vehicle VA is traveling at a position closer to the predicted collision point CPP than the first predetermined position P1 toward the predicted collision point CPP or that the right turning vehicle VA is present at a position closer to the predicted collision point CPP than a second predetermined position P2 between the first predetermined position P1 and the predicted collision point CPP.

[0058] Fig. 13 is a schematic diagram illustrating a positional relationship between the right turning vehicle VA and the straight traveling vehicle VB at a timing at which the right turning vehicle VA moves ahead inside the intersection CS and approaches the intersection center CTR after entering the intersection CS.

[0059] In the present embodiment, the predicted collision area ACP with the predicted collision point CPP included at its center is set as an area that is different from the intersection area ACS. The traveling of the right turning vehicle VA at a position closer to the predicted collision point CPP than the first predetermined position P1 or presence of the right turning vehicle VA at a position closer to the predicted collision point CPP than the second predetermined position P2 is detected on the basis of the right turning vehicle VA traveling toward the predicted collision point CPP inside the intersection area ACS or being present inside the predicted collision area ACP after entering the intersection area ACS. The second vehicle behavior detection unit B117a sets the timing at which traveling of the right turning vehicle VA toward the predicted collision point CPP inside the intersection area ACS or presence of the right turning vehicle VA inside the predicted collision area ACP is detected as a second notification issuance timing. The second notification issuance timing set by the second vehicle behavior detection unit B117a is a timing at which the right turning vehicle VA performs notification issuance in a second predetermined mode. The predicted collision area ACP is set as a circular area that includes the second predetermined position P2 on its outer edge and has a smaller area than the intersection area ACS.

[0060] The shape of the intersection area ACS is not limited to the circular shape and may be a shape (for example, a quadrangular shape having four corners at a corner cut) following a range in which the two intersecting roads overlap or may be a shape within a range surrounded by the stop lines SL1 and SL2 provided in the intersecting roads, respectively. The same applies to the predicted collision area ACP, and it is possible to set a shape other than the circular shape, such as a quadrangular shape (for example, a quadrangular shape having two sides that are parallel to a road boundary line defining the opposite straight lane L22).

[0061] The first notification issuing unit B118a outputs a command signal to perform notification issuance in the first predetermined mode to the HMI device 131a included in the host vehicle (that is, the right turning vehicle VA) under a condition that a first predetermined notification issuance condition defined in advance in regard to the position Pb of another vehicle, which is the straight traveling vehicle VB, is met at the timing at which the presence of the right turning vehicle VA at the first predetermined position P1 in the right turn lane L11 or a position closer to the intersection center CTR than the first predetermined position P1 is detected, that is, at the first notification issuance timing. In the present embodiment, the output of the command signal to perform the notification issuance in the first predetermined mode from the first notification issuing unit B118a to the HMI device 131a is regarded as "execution of the notification issuance in the first predetermined mode".

[0062] The first predetermined notification issuance condition is that the straight traveling vehicle VB is present at a first predetermined distance (hereinafter, referred to as an "information presentation distance") Dth1, which is relatively long, from the intersection CS or at a position closer to the intersection CS than the first predetermined distance Dth1. In the present embodiment, the distance from the outer edge of the predicted collision area ACP, specifically, an intersecting point between the traveling path TRb of the straight traveling vehicle VB and the circle (the circle illustrated by the dashed line in the drawings) defining the outer edge of the predicted collision area ACP to the straight traveling vehicle VB as illustrated in Figs. 12 and 13 is employed as a distance Db from the intersection CS to the straight traveling vehicle VB.

[0063] The HMI device 131a that has received the command signal from the first notification issuing unit B118a to perform the notification issuance in the first predetermined mode issues a notification to promote the driver of the right turning vehicle VA to recognize that the straight traveling vehicle VB traveling toward the intersection CS in the opposite straight lane L22 is present using display and sound. The notification issuance performed by the first notification issuing unit B118a is notification issuance to present information for relatively low urgency in regard to collision between the right turning vehicle VA and the straight traveling vehicle VB.

[0064] The second notification issuing unit B119a outputs a command signal to issue a notification in a second predetermined mode to the HMI device 131a under a condition that a second predetermined notification issuance condition defined in advance in regard to the position Pb of the straight traveling vehicle VB is established at a timing at which traveling of the right turning vehicle VA at a position closer to the predicted collision point CPP than the first predetermined position P1 or presence of the right turning vehicle VB at a position closer to the predicted collision point CPP than the second predetermined position P2 is detected, that is, at the first notification issuance timing. In the present embodiment, the output of the command signal to perform the notification issuance in the second predetermined mode from the second notification issuing unit B119a to the HMI device 131a is regarded as "execution of the notification issuance in the second predetermined mode".

[0065] The second predetermined notification issuance condition is that the straight traveling vehicle VB is present at a second predetermined distance (hereinafter, referred to as an "alarm distance") Dth2, which is shorter than the information presentation distance Dth1, from the intersection CS or at a position closer to the intersection CS than the second predetermined distance Dth2.

[0066] The notification issuance in the second predetermined mode is notification issuance in a mode that is different from the first predetermined mode, and the HMI device 131a that has received the command signal from the second notification issuing unit B119a to perform the notification issuance in the second predetermined mode issues a notification to promote the driver of the right turning vehicle VA to recognize higher urgency in regard to collision between the right turning vehicle VA and the straight traveling vehicle VB using display and sound. The notification issuance performed by the second notification issuing unit B119a is notification issuance that is more prominent and more visually or auditorily appealing to the driver as compared with the notification issuance performed by the first notification issuing unit B118a.

[0067] The first notification issuing unit B118a and the second notification issuing unit B119a can also provide a notification that the notification issuance in each mode (the notification issuance in the first predetermined mode and the notification issuance in the second predetermined mode) has been performed to the straight traveling vehicle VB via the transmitter 121a together with the output of the command signal to the HMI device 131a and promote the straight traveling vehicle VB to perform notification issuance in an appropriate mode in accordance with a degree of urgency in regard to collision against the host vehicle (that is, the right turning vehicle VA).

[0068] Fig. 10 is an explanatory diagram illustrating a method of calculating the information presentation distance Dth1 and the alarm distance Dth2.

[0069] The information presentation distance Dth1 and the alarm distance Dth2 are calculated as a distance by which the straight traveling vehicle VB is expected to travel before stopping after the notification issuance, that is, the distance required by the straight traveling vehicle VB to stop on the basis of the vehicle speed VSPb of the straight traveling vehicle VB and deceleration degrees DEC1 and DEC2 set in advance in accordance with the modes of the notification issuance. Hereinafter, the deceleration degree DEC1 may be referred to as a "first predetermined deceleration degree DEC1". The deceleration degree DEC2 may be referred to as a "second predetermined deceleration degree DEC2".

[0070] Specifically, the information presentation distance Dth1 is calculated by adding the distances for which the straight traveling vehicle VB is expected to travel for a break reaction time PRD1 and a deceleration time PRD2 on the basis of the vehicle speed VSPb (= V1) of the straight traveling vehicle VB at the detection timing of the first vehicle behavior detection unit B116a. The break reaction time PRD1 is a total time of a reaction time required for perception, judgment, and operation before the driver actually performs a brake operation after the notification issuance and an operation delay time for the system, hydraulic equipment, and the like in response to the brake operation. In the present embodiment, the break reaction time PRD1 is set in advance as a constant time (= ΔT). The deceleration time PRD2 is a time required for the vehicle to come to a stop after the brake actually starts to work and can be calculated on the basis of the vehicle speed VSPb and the deceleration degree DEC1 (PRD2 = V1 / DEC1). In this manner, the calculation of the information presentation distance Dth1 is given by Equation (1) below. Dth 1 = V 1 × ΔT + V 1 × V 1 / DEC 1 / 2

[0071] Although the alarm distance Dth2 is similarly calculated by adding the distance for which the straight traveling vehicle VB is expected to travel for each of the break reaction time PRD1 and the deceleration time PRD2, the deceleration degree DEC2 which is different from that used to calculate the information presentation distance Dth1 is employed. The deceleration degree DEC2 for calculating the alarm distance is a higher deceleration degree than the deceleration degree DEC1 for calculating the information presentation distance, in other words, a deceleration degree having a larger absolute value than that of the deceleration degree DEC1 (|DEC1| < |DEC2|). Specifically, it is given by Equation (2) below. Dth 2 = V 1 × ΔT + V 1 × V 1 / DEC 2 / 2

[0072] Fig. 22 is a schematic diagram illustrating a positional relationship between the right turning vehicle VA and the straight traveling vehicle VB at a timing when the right turning vehicle VA enters the virtual intersection VCS. Fig. 22 illustrates only the right turn lane L11 and the straight lane L22 in the road R with two lanes on each side by simplifying the illustration of the road R. Similarly, the illustration of the road R in each of Figs. 23 to 26, which will be described later, is also simplified.

[0073] In the present embodiment, a virtual intersection area VACS is set under a condition that a predetermined setting condition is met in a case where the right turning vehicle VA turns right at the virtual intersection VCS. The virtual intersection area VACS is used as a determination criterion for recognizing a relative positional relationship between the right turning vehicle VA and the virtual intersection VCS. Additionally, the virtual intersection area VACS serves as a trigger for the notification system 1 to specify the right turning vehicle VA turning right at the virtual intersection VCS as a vehicle to which attention is to be paid. The setting of the virtual intersection area VACS is performed by the virtual area setting unit B122a. The virtual intersection area VACS is set to encompass the virtual intersection center VCTR in a case where a point at which a right turning path TRa' that is a path where the right turning vehicle VA travels when the right turning vehicle VA passes the virtual intersection VCS, that is, when the right turning vehicle VA crosses the opposite lane L22 and turns right to enter the predetermined area PA located on the roadside along the opposite lane L22 and the center line CL that sections the traveling lane L11 and the opposite lane L22 intersect as the virtual intersection center VCTR. In other words, the virtual intersection area VACS is set to overlap with the right turning path TRa'. Presence of the right turning vehicle VA at a predetermined position relative to the virtual intersection VCS is detected on the basis of the right turning vehicle VA reaching the virtual intersection area VACS or entering the virtual intersection area VACS. The virtual intersection area VACS may be set as a circular area with a predetermined radius centered at the virtual intersection center VCTR, for example. Figs. 22 to 24 illustrate the virtual intersection area VACS by two-dotted chain lines, illustrate the right turning path TRa' of the right turning vehicle VA by one-dotted chain lines, and illustrate a virtual predicted collision area VACP and a traveling path TRb' of the straight traveling vehicle VB, which will be described later, by dashed lines and one-dotted chain lines, respectively.

[0074] Fig. 23 is a schematic diagram illustrating a positional relationship between the right turning vehicle VA and the straight traveling vehicle VB at a timing at which the right turning vehicle VA moves ahead inside the virtual intersection VCS and approaches the virtual intersection center VCTR after entering the virtual intersection VCS.

[0075] In the present embodiment, the virtual predicted collision area VACP is set as an area that is different from the virtual intersection area VACS under a condition that the same predetermined setting condition as that for setting the virtual intersection area VACS is met in a case where the right turning vehicle VA turns right at the virtual intersection VCS. The setting of the virtual predicted collision area VACP is performed by the virtual area setting unit B122a similarly to the virtual intersection area VACS. The virtual predicted collision area VACP is set to encompass a virtual predicted collision point VCPP in a case where the point at which the right turning path TRa' of the right turning vehicle VA and the straight traveling path TRb' that is a path where the straight traveling vehicle VB travels intersect as the virtual predicted collision point VCPP. In other words, the virtual predicted collision area VACP is set to overlap with the right turning path TRa'. Traveling of the right turning vehicle VA toward the virtual predicted collision point VCPP inside the virtual intersection area VACS or presence of the right turning vehicle VA inside the virtual predicted collision area VACP is detected after the right turning vehicle VA enters the virtual intersection area VACS. The virtual predicted collision area VACP is set as a circular area with a predetermined radius and a smaller area than the virtual intersection area VACS. Note that the straight traveling path TRb' of the straight traveling vehicle VB can be replaced with a virtual straight line that passes the center of the lane L22 where the straight traveling vehicle VB is present and is parallel to the center line CL.

[0076] The shape of the virtual intersection area VACS is not limited to the circular shape around the virtual intersection center VCTR, and the virtual intersection area VACS may be, for example, the virtual intersection VCS itself. The same applies to the virtual predicted collision area VACP, and it is possible to set a quadrangular shape that has two sides parallel to the road boundary line that defines the opposite lane L22 for straight traveling vehicles, for example, or a shape other than the circular shape.

[0077] The third vehicle behavior detection unit B120a detects that the right turning vehicle VA is present at a predetermined position relative to the virtual intersection VCS, specifically that the right turning vehicle VA is at a predetermined distance from the virtual intersection center VCTR, which is a center position of the virtual intersection VCS, or has approached the virtual intersection center VCTR than the predetermined distance, on the basis of the current position Pa of the right turning vehicle VA on the road map. In other words, the third vehicle behavior detection unit B120a detects that the right turning vehicle VA has reached the virtual intersection area VACS or has entered the virtual intersection area VACS. Then, the third vehicle behavior detection unit B120a sets a timing at which any of these behaviors of the right turning vehicle VA is detected as a third notification issuance timing. The third notification issuance timing set by the third vehicle behavior detection unit B120a is a timing at which the right turning vehicle VA performs notification issuance in the third predetermined mode.

[0078] The first notification issuing unit B118a outputs a command signal to perform the notification issuance in the third predetermined mode to the HMI device 131a included in the host vehicle (that is, the right turning vehicle VA) under the condition that a third predetermined notification issuance condition defined in advance in regard to the position Pb of another vehicle, which is the straight traveling vehicle VB, is met at the third notification issuance timing set by the third vehicle behavior detection unit B120a. In the present embodiment, content of the notification issuance in the third predetermined mode is the same as the content of the notification issuance in the first predetermined mode. The content of the notification issuance in the third predetermined mode is not limited thereto and may be different from the content of the notification issuance in the first predetermined mode.

[0079] The third predetermined notification issuance condition is that the straight traveling vehicle VB is present at a third predetermined distance (hereinafter, referred to as an "information presentation distance") Dth3, which is relatively long, from the virtual intersection VCS or at a position closer to the virtual intersection VCS than the third predetermined distance Dth3. In the present embodiment, the distance from the outer edge of the virtula predicted collision area VACP, specifically, an intersecting point between the traveling path TRb' of the straight traveling vehicle VB and the circle (the circle illustrated by the dashed line in the drawings) defining the outer edge of the virtual predicted collision area VACP to the straight traveling vehicle VB as illustrated in Figs. 22 and 23 is employed as a distance Db' from the virtual intersection VCS to the straight traveling vehicle VB.

[0080] In the present embodiment, the information presentation distance Dth3 can be calculated in the same manner as the information presentation distance Dth1. The information presentation distance Dth3 is calculated by adding the distances for which the straight traveling vehicle VB is expected to travel for the break reaction time PRD1 and the deceleration time PRD2 on the basis of the vehicle speed VSPb (= V1') of the straight traveling vehicle VB at the third notification issuance timing set by the third vehicle behavior detection unit B120a. When a deceleration degree for calculating the information presentation distance is set in advance as a third predetermined deceleration degree DEC3 according to the notification issuance in the third predetermined mode, the calculation of the information presentation distance Dth3 is given by Equation (3) below. Dth 3 = V 1 ′ × ΔT + V 1 ′ × V 1 ′ / DEC 3 / 2

[0081] Note that in the present embodiment, the third predetermined deceleration degree DEC3 is the same deceleration degree as the first predetermined deceleration degree DEC1. However, the third predetermined deceleration degree DEC3 is not limited thereto and may be a deceleration degree different from the first predetermined deceleration degree DEC1.

[0082] The fourth vehicle behavior detection unit B121a monitors a behavior of the right turning vehicle VA after the setting of the third notification issuance timing. In other words, the fourth vehicle behavior detection unit B121a monitors a behavior of the right turning vehicle VA after entering the virtual intersection area VACS. The fourth vehicle behavior detection unit B121a detects whether the right turning vehicle VA is traveling toward the virtual predicted collision point VCPP inside the virtual intersection area VACS or is present inside the virtual predicted collision area VACP on the basis of the current position Pa of the right turning vehicle VA on the road map. Then, the fourth vehicle behavior detection unit B121a sets the timing at which any of these behaviors of the right turning vehicle VA is detected as a fourth notification issuance timing. The fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a is a timing at which the right turning vehicle VA performs notification issuance in the fourth predetermined mode.

[0083] The second notification issuing unit B119a outputs a command signal to issue a notification in a fourth predetermined mode to the HMI device 131a under a condition that a fourth predetermined notification issuance condition defined in advance in regard to the position Pb of the straight traveling vehicle VB is established at the fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a. In the present embodiment, content of the notification issuance in the fourth predetermined mode is the same as the content of the notification issuance in the second predetermined mode. The content of the notification issuance in the fourth predetermined mode is not limited thereto and may be different from the content of the notification issuance in the second predetermined mode.

[0084] The fourth predetermined notification issuance condition is that the straight traveling vehicle VB is present at a fourth predetermined distance (hereinafter, referred to as an "alarm distance") Dth4, which is shorter than the information presentation distance Dth3, from the virtual intersection VCS or at a position closer to the virtual intersection VCS than the fourth predetermined distance Dth4.

[0085] In the present embodiment, the alarm distance Dth4 can be calculated in the same manner as the alarm distance Dth2. The alarm distance Dth4 is calculated by adding the distances for which the straight traveling vehicle VB is expected to travel for the break reaction time PRD1 and the deceleration time PRD2 on the basis of the vehicle speed VSPb (= V1') of the straight traveling vehicle VB at the fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a. When a deceleration degree for calculating the alarm distance is larger than the third predetermined deceleration DEC3 and is set in advance as a fourth predetermined deceleration degree DEC4 according to the notification issuance in the fourth predetermined mode, the calculation of the alarm distance Dth4 is given by Equation (4) below. Dth 4 = V 1 ′ × ΔT + V 1 ′ × V 1 ′ / DEC 4 / 2

[0086] However, the absolute value of the fourth predetermined deceleration degree DEC4 is greater than that of the third predetermined deceleration degree DEC3.

[0087] Note that in the present embodiment, the third predetermined deceleration degree DEC3 is the same deceleration degree as the first predetermined deceleration degree DEC1. However, the third predetermined deceleration degree DEC3 is not limited thereto and may be a deceleration degree different from the first predetermined deceleration degree DEC1.

[0088] The notification issuance in the second predetermined mode is notification issuance in a mode that is different from the third predetermined mode, and the HMI device 131a that has received the command signal from the second notification issuing unit B119a to perform the notification issuance in the fourth predetermined mode issues a notification to promote the driver of the right turning vehicle VA to recognize higher urgency in regard to collision between the right turning vehicle VA and the straight traveling vehicle VB using display and sound.

[0089] The first notification issuing unit B118a and the second notification issuing unit B119a can also provide a notification that the notification issuance in each mode (the notification issuance in the third predetermined mode and the notification issuance in the fourth predetermined mode) has been performed to the straight traveling vehicle VB via the transmitter 121a together with the output of the command signal to the HMI device 131a and promote the straight traveling vehicle VB to perform notification issuance in an appropriate mode in accordance with a degree of urgency in regard to collision against the host vehicle (that is, the right turning vehicle VA).

[0090] The virtual area setting unit B122a regards the fact that the right turning vehicle VA is present in the traveling lane L11 while the straight traveling vehicle VB is present in the opposite lane L22 and the right turn intention detection unit B114a has detected the right turn intention of the right turning vehicle VA as a predetermined setting condition and sets the virtual intersection area VACS and the virtual predicted collision area VACP in an associated manner on the road map in a case where the predetermined setting condition is met. In the present embodiment, the virtual area setting unit B122a sets the virtual intersection area VACS and the virtual predicted collision area VACP on the map in the specific range or the specific section extracted by the road map storage unit B113a. Thus, the third vehicle behavior detection unit B120a can set the third notification issuance timing, and the fourth vehicle behavior detection unit B121a can set the fourth notification issuance timing. Furthermore, the first notification issuing unit B118a can perform the notification issuance in the third predetermined mode with an intention to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA, and the second notification issuing unit B119a can perform notification issuance in the fourth predetermined mode with an intention to provide an alarm to promote recognition of high urgency in regard to the collision between the straight traveling vehicle VB and the right turning vehicle VA. Therefore, even in a case where the right turning path TRa' of the right turning vehicle VA and the straight traveling path TRb' of the straight traveling vehicle VB intersect at a location other than the intersection CS of the road R, it is possible to provide a notification that assists in avoiding collision between the right turning vehicle VA and the straight traveling vehicle VB. In other words, it is possible to perform notification issuance in an appropriate mode at an appropriate timing in accordance with a degree of urgency of a situation where there is a concern that the right turning vehicle VA and the straight traveling vehicle VB may collide against each other at a location other than the intersection CS of the road R.

[0091] Fig. 25 is a schematic diagram illustrating the right turning path TRa' of the right turning vehicle VA set by the virtual area setting unit B122a.

[0092] Here, the right turning path TRa' set by the virtual area setting unit B122a will be described with reference to Fig. 25. The right turning path TRa' is used when the virtual area setting unit B122a sets the virtual intersection center VCTR, the virtual intersection VCS, the virtual predicted collision point VCPP, the virtual intersection area VACS, and the virtual predicted collision area VACP in an associated manner on the road map as illustrated in Figs. 22 to 24. The right turning path TRa' is set as follows, for example.

[0093] First, the virtual area setting unit B122a detects a roadside building RB located on the roadside along the opposite lane L22 of the road R, which is the closest to a point Ps on the road R separated from the right turning vehicle VA on the front side by a specific distance Dpa, as a predetermined area PA from among a plurality of roadside buildings RB in the map in the specific range or the specific section extracted by the road map storage unit B113a at the timing at which the right turn intention of the right turning vehicle VA is detected. The point Ps is a point where it is predicted that the right turning vehicle VA will start to turn right. In other words, the distance Dpa is the distance from the position of the right turning vehicle VA at the timing at which its intention to turn right is detected to the point where it is predicted that the right turning vehicle VA will start to turn right. The specific distance is, for example, 30 meters (m).

[0094] Next, the virtual area setting unit B122a sets a traveling path serving as a norm when the right turning vehicle VA turns right and enters the predetermined area PA as the right turning path TRa' on the map using the detected predetermined area PA as a base point, more specifically, using the representative position of the predetermined area PA as a base point. In a case where the road map has the position information regarding an entrance of the predetermined area PA, the representative position of the predetermined area PA may also be the position of the entrance of the predetermined area PA. The entrance of the predetermined area PA is provided to be continuous with the opposite lane L22.

[0095] Note that he virtual area setting unit B122a can set the right turning path TRa' even if the predetermined setting condition for setting the virtual intersection area VACS and the virtual predicted collision area VACP has not been met as long as the right turn intention of the right turning vehicle VA has been detected. In other words, the virtual area setting unit B122a can set the right turning path TRa' even in a situation where the straight traveling vehicle VB is not present in the lane L22. Moreover, the virtual area setting unit B122a does not set the right turning path TRa' in a case where a continuous median strip is present at a position where the right turning path TRa' is to be set on the map and the right turning vehicle VA cannot turn right. Additionally, the notification system 1 may include an in-vehicle camera (not illustrated) that images the front of the vehicle, for example. Furthermore, the virtual area setting unit B122a may be configured not to set the right turning path TRa' in a case where the median strip or a road sign prohibiting crossing across the opposite lane L22 is detected from an image captured by the in-vehicle camera.

[0096] Also, the first notification issuing unit B118a may not output the command signal to perform the notification issuance in the third predetermined mode, and the second notification issuing unit B119a may not output the command signal to perform the notification issuance in the fourth predetermined mode in a case where the right turning vehicle VA is present in the traveling lane L11 leading to the intersection CS in order to turn right at the intersection CS of the road R and the right turning vehicle VA has entered the intersection area ACS that overlaps the path where the right turning vehicle VA travels when the right turning vehicle VA passes the intersection CS and that is set in advance in association with the road map. Thus, the first notification issuing unit B118a prioritizes the output of the command signal to perform the notification issuance in the first predetermined mode to the HMI device 131a and the execution of the notification issuance in the first predetermined mode over the command signal to perform the notification issuance in the third predetermined mode. Furthermore, the second notification issuing unit B119a prioritizes the output of the command signal to perform the notification issuance in the second predetermined mode to the HMI device 131a and execution of the notification issuance in the second predetermined mode over the command signal to perform the notification issuance in the fourth predetermined mode. In other words, the notification system 1 uses the intersection area ACS and the predicted collision area ACP as a condition to set the predetermined notification issuance timing and a condition to perform the notification issuance in the predetermined mode in a case where the right turning vehicle VA turns right at the intersection CS, the position of which on the map is set in advance, and uses the virtual intersection area VACS and the virtual predicted collision area VACP as a condition to set the predetermined notification issuance timing and a condition to perform the notification issuance in the predetermined mode in a case where the right turning vehicle VA turns right at the virtual intersection VCS. Thus, the notification system 1 can distinguish the case of turning right at the intersection CS and the case of turning right at a location other than the intersection CS, that is, turning right at the virtual intersection VCS and can perform the notification issuance in an appropriate predetermined mode when the right turning vehicle VA passes the intersection CS in a case where the right turning vehicle VA actually passes the intersection CS even after the setting of the virtual intersection area VACS and the virtual predicted collision area VACP.

[0097] Moreover, the virtual area setting unit B122a may not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB exceeds a fifth predetermined distance (hereinafter, a predetermined separation distance) Dth5 that is relatively long. A risk of collision against the straight traveling vehicle VB is low even if the right turning vehicle VA turns right and crosses the opposite lane L22 in a case where the right turning vehicle VA and the straight traveling vehicle VB are present at a sufficiently long distance exceeding the predetermined separation distance Dth5. Therefore, the virtual area setting unit B122a does not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance between the right turning vehicle VA and the straight traveling vehicle VB exceeds the predetermined separation distance Dth5 even if the aforementioned predetermined setting condition has been met. A calculation load is thus reduced as compared with a case where the unnecessary virtual intersection area VACS and virtual predicted collision area VACP are set. On the other hand, the virtual area setting unit B122a can execute the notification in the predetermined mode with an appropriate positional relationship between the right turning vehicle VA and the straight traveling vehicle VB by setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance between the right turning vehicle VA and the straight traveling vehicle VB is equal to or less than the predetermined separation distance Dth5.

[0098] Note that the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB can be obtained from the current position Pa of the right turning vehicle VA and the current position Pb of the straight traveling vehicle VB as coordinate information on the road map. Moreover, the predetermined separation distance Dth5 is, for example, a distance that is sufficiently longer than the information presentation distance Dth3.

[0099] Additionally, the virtual area setting unit B122a may not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where a predetermined vehicle speed VSP1, which will be described later, is defined as a first predetermined vehicle speed VSP1 and the vehicle speed VSPa of the right turning vehicle VA exceeds a second predetermined vehicle speed VSP2 that is a vehicle speed higher than the first predetermined vehicle speed VSP1. In general, vehicles reduce their vehicle speeds to make a right turn. In other words, vehicles are likely not to turn right in a case where the vehicle speeds are not reduced. Therefore, the virtual area setting unit B122a determines that the right turning vehicle VA will not turn right and does not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the vehicle speed VSPa of the right turning vehicle VA exceeds the second predetermined vehicle speed VSP2 even in a case where the aforementioned predetermined setting condition has been met. A calculation load is thus reduced as compared with a case where the virtual intersection area VACS and the virtual predicted collision are VACP, which are not necessary because the right turning vehicle VA does not turn right, are set. On the other hand, the virtual area setting unit B122a can execute the notification in a predetermined mode with an appropriate positional relationship between the right turning vehicle VA and the straight traveling vehicle VB by setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the second predetermined vehicle speed VSP2. Note that the second predetermined vehicle speed VSP2 is, for example, 50 km / h.

[0100] Additionally, the virtual intersection area VACS may include four vertices of the virtual intersection VCS on its outer edge. In other words, the virtual area setting unit B122a may set the virtual intersection area VACS with an outer edge that includes the four vertices of the virtual intersection VCS. As described above, the virtual intersection area VACS is a square section with a side corresponding to the road width W of the road R. Therefore, the virtual area setting unit B122a sets the virtual intersection area VACS with an area size (wideness) in accordance with the location where the right turning vehicle VA turns right on the road R in the virtual intersection area VACS by setting the virtual intersection area VACS with the outer edge that includes the four vertices of the virtual intersection VCS. This allows the virtual intersection area VACS to be used more appropriately as a determination criterion for recognizing the relative positional relationship between the right turning vehicle VA and the virtual intersection VCS.

[0101] Furthermore, the virtual area setting unit B122a may set the virtual intersection area VACS such that the right turning vehicle VA is not present inside the virtual intersection area VACS and the outer edge of the virtual intersection area VACS is located just in front of the right turning vehicle VA. Thus, the right turning vehicle VA reaches the virtual intersection area VACS or enters the virtual intersection area VACS in a relatively short time after the virtual intersection area VACS is set, the third vehicle behavior detection unit B120a can set the third notification issuance timing, and the fourth vehicle behavior detection unit B121a can then set the fourth notification issuance timing. In other words, the notification issuance in the third predetermined mode with an intention to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA and the notification issuance in the fourth predetermined mode with an intention to provide an alarm to promote recognition of high urgency are more reliably performed. Note that the virtual area setting unit B122a may set the virtual intersection area VACS such that a part of a front portion of the right turning vehicle VA is present inside the virtual intersection area VACS.

[0102] Additionally, the virtual area setting unit B122a may set the right turning path TRa' in an associated manner on the road map on the basis of destination information of the navigation device 115a in which the predetermined area PA is set as a destination or at least one of the vehicle speed VSPa of the right turning vehicle VA and a steering amount of the right turning vehicle VA detected by the steering angle sensor 114a, which is a steering amount detection section.

[0103] Specifically, the virtual area setting unit B122a detects the predetermined area PA from the map in the specific range or the specific section extracted by the road map storage unit B113a on the basis of the destination information of the navigation device 115a in a case where a right turn intention of the right turning vehicle VA is detected. Then, the virtual area setting unit B122a sets the traveling path, which serves as a norm when the right turning vehicle VA turns right and enters the predetermined area PA, as the right turning path TRa' on the map using the detected predetermined area PA as a base point. The virtual area setting unit B122a can thus accurately set the right turning path TRa' while reducing the calculation load as compared with processing for specifying the predetermined area PA using the specific distance Dpa, which is the distance from the position of the right turning vehicle VA at the timing at which the right turn intention of the right turning vehicle VA is detected to the point where it is predicted that the right turning vehicle VA will start to turn right. In other words, the virtual area setting unit B122a improves setting accuracy of the virtual intersection area VACS and the virtual predicted collision area VACP on the basis of the accurately set right turning path TRa'. It is thus possible to accurately perform the notification issuance in a predetermined mode based on the virtual intersection area VACS and the virtual predicted collision area VACP.

[0104] Furthermore, the virtual area setting unit B122a determines that the right turning vehicle VA will turn right and enter another predetermined area PA that is present at a position closer to the right turning vehicle VA than the predetermined area PA detected from the map at the timing at which the right turn intention of the right turning vehicle VA is detected in a case where the steering angle of the right turning vehicle VA detected by the steering angle sensor 114a has significantly changed rightward, and / or the vehicle speed VSPa of the right turning vehicle VA detected by the vehicle speed sensor 112a has significantly dropped after the detection of the right turn intention of the right turning vehicle VA. In other words, the virtual area setting unit B122a determines such behavior changes of the right turning vehicle VA as signs of a right turn. Then, the virtual area setting unit B122a performs correction to shorten the specific distance Dpa as a change in steering angle in the right rotation direction of the right turning vehicle VA is greater and / or as the decrease in vehicle speed VSPa of the right turning vehicle VA is greater, detects the predetermined area PA again on the basis of the specific distance Dpa after the correction, and resets the right turning path TRa'. An error between the right turning path TRa' and the traveling path when the right turning vehicle VA actually turns right thus decreases, and the virtual area setting unit B122a improves setting accuracy of the virtual intersection area VACS and the virtual predicted collision area VACP set on the basis of the right turning path TRa'. In other words, it is possible to accurately perform the notification issuance in a predetermined mode based on the virtual intersection area VACS and the virtual predicted collision area VACP.

[0105] Fig. 26 is a schematic diagram illustrating virtual intersection area candidates VACSC and virtual predicted collision area candidates VACPC generated by the virtual area setting unit B122a.

[0106] As illustrated in Fig. 26, the virtual area setting unit B122a may determine the virtual intersection area VACS from among at least one virtual intersection area candidate VACSC, which is a candidate for the virtual intersection area VACS, and determine the virtual predicted collision area VACP from among at least one virtual predicted collision area candidate VACPC, which is a candidate for the virtual predicted collision area VACP, by determining the predetermined area PA from at least one predetermined area candidate PAC, which is a candidate for the predetermined area PA, when the virtual intersection area VACS and the virtual predicted collision area VACP are set. In this case, the virtual area setting unit B122a specifically performs the following series of processing. Note that the virtual area setting unit B122a may constantly perform the following series of processing when the right turning vehicle VA is present in the traveling lane.

[0107] First, the virtual area setting unit B122a detects at least one roadside building RB that is located in the traveling direction of the right turning vehicle VA, that is, on the front side and is located on the roadside along the opposite lane L22 of the road R from the road map on the basis of the current position Pa of the right turning vehicle VA specified on the road map. The virtual area setting unit B122a sets at least one detected roadside building RB as a candidate for the predetermined area PA which the right turning vehicle VA may turn right and enter in the future, that is, predetermined area candidate PAC. Note that the number of predetermined area candidates PAC is not particularly limited.

[0108] Next, the virtual area setting unit B122a sets a normative path where the right turning vehicle VA will travel to turn right and enter each of at least one predetermined area candidate PAC set as a right turning path candidate TRa'C, which is a candidate for the right turning path TRA', in an associated manner on the road map.

[0109] Next, the virtual area setting unit B122a sets a point at which the at least one right turning path candidate TRa'C set and the center line CL of the road R intersect as a virtual intersection center candidate VCTRC, which is a candidate for the virtual intersection center VCTR, and sets a point at which the right turning path candidate TRa'C and the straight traveling path TRb' as a virtual straight line that passes the center of the lane L22 and is parallel to the center line CL intersect as a virtual predicted collision point candidate VCPPC, which is a candidate for the virtual predicted collision point VCPP, in an associated manner on the road map. At this time, the virtual area setting unit B122a also sets a virtual intersection candidate VCSC, which is a candidate for the virtual intersection VCS corresponding to each virtual intersection center candidate VCTRC, in an associated manner on the road map.

[0110] Next, the virtual area setting unit B122a sets the virtual intersection area candidate VACSC that is a candidate for the virtual intersection area VACS and includes each virtual intersection center candidate VCTRC and the virtual predicted collision area candidate VACPC that is a candidate for the virtual predicted collision area VACP and includes each virtual predicted collision point candidate VCPPC in an associated manner on the road map.

[0111] Then, the virtual area setting unit B122a determines the predetermined area PA from among at least one predetermined area candidate PAC in a case where the aforementioned predetermined setting condition to set the virtual intersection area candidate VACSC and the virtual predicted collision area VACP is met, and thereby determines the determined predetermined area PA, that is, the right turning path candidate TRa'C, the virtual intersection center candidate VCTRC, the virtual predicted collision point candidate VCPPC, the virtual intersection area candidate VACSC, and the virtual predicted collision area candidate VACPC as the right turning path TRa', the virtual intersection center VCTR, the virtual predicted collision point VCPP, the virtual intersection area VACS, and the virtual predicted collision area VACP, respectively.

[0112] The virtual area setting unit B122a sets and holds the predetermined area candidate PAC that the right turning vehicle VA may turn right and enter, the virtual intersection area candidate VACSC, the virtual predicted collision area candidate VACPC, and the like associated with the predetermined area candidate PAC in advance in this manner before the predetermined setting condition to set the virtual intersection area VACS and the virtual predicted collision area VACP is met. The processing to generate the virtual intersection area VACS, the virtual predicted collision area VACP, and the like on the basis of the right turning path TRa' after the predetermined setting condition is met becomes unnecessary, which leads to a decrease in calculation load. In this manner, the virtual area setting unit B122a shortens the setting processing time for the virtual intersection area VACS and the virtual predicted collision area VACP, allowing for the setting of the virtual intersection area VACS and the virtual predicted collision area VACP with no delay, thereby improving accuracy when the notification in a predetermined mode is performed.

[0113] Furthermore, the virtual area setting unit B122a may use at least one of the steering amount of the right turning vehicle VA detected by the steering angle sensor 114a, which serves as the steering amount detection and notification section, and the vehicle speed VSPa of the right turning vehicle VA to determine the predetermined area PA from among at least one predetermined area candidate PAC. In other words, the virtual area setting unit B122a may determine the predetermined area PA from among at least one predetermined area candidate PAC on the basis of at least one of the steering amount of the right turning vehicle VA detected by the steering angle sensor 114a as the steering amount detection and notification section and the vehicle speed VSPa of the right turning vehicle VA.

[0114] Specifically, the method of setting the right turning path TRa' on the basis of the specific distance Dpa illustrated in Fig. 25 described above is partially used. In other words, correction is performed to shorten the specific distance Dpa as the change in steering angle in the rightward direction of the right turning vehicle VA is greater and / or as the decrease in vehicle speed VSPa of the right turning vehicle VA is greater after the right turn intention of the right turning vehicle VA is detected, and a predetermined area candidate PAC that is the closest from the point Ps on the road R separated from the position of the right turning vehicle VA at the point where the right turn intention of the right turning vehicle VA is detected on the front side by the specific distance Dpa after the correction as the predetermined area PA. In this manner, the virtual area setting unit B122a can set the virtual intersection area VACS and the virtual predicted collision area VACP accurately and without delay, enabling more precise notification in the predetermined mode.

[0115] In the present embodiment, the controller 101a included in the right turning vehicle VA and the controller 101b included in the straight traveling vehicle VB have basically similar configurations and include mutually corresponding elements.

[0116] As illustrated in Fig. 3, the controller 101b of the straight traveling vehicle VB includes a host vehicle position detection unit B111b, an other vehicle position detection unit B112b, a road map storage unit B113b, a right turn intention detection unit B114b, a vehicle speed detection unit B115b, a first vehicle behavior detection unit B116b, a second vehicle behavior detection unit B117b, a first notification issuing unit B118b, a second notification issuing unit B119b, a third vehicle behavior detection unit B120b, a fourth vehicle behavior detection unit B121b, and a virtual area setting unit B122b. Differences between an internal configuration of the controller 101b and that of the controller 101a of the right turning vehicle VA will be mainly described below.

[0117] The host vehicle position detection unit B111b is adapted to detect the current position Pb of the straight traveling vehicle VB, which is the host vehicle, and the detection of the current position Pb is based on an output signal from the position sensor 111b included in the straight traveling vehicle VB.

[0118] The other vehicle position detection unit B112b is adapted to detect the current position Pa of the right turning vehicle VA, which is another vehicle, and the detection of the current position Pa is based on reading of position information indicating the current position Pa from vehicle information acquired from the right turning vehicle VA via the receiver 122b included in the straight traveling vehicle VB.

[0119] Similarly to the road map storage unit B113a, the road map storage unit B113b stores a road map that includes the intersection CS and includes an assigned link ID of each lane leading to the intersection CS (a map in a range or a section including the intersection CS) and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA, respectively, on the road map. Similarly to the road map storage unit B113a, the road map storage unit B113b stores a road map that includes an assigned link ID of each lane leading to the virtual intersection VCS (a map in a specific range or a specific section) and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA, respectively, on the road map. Although the road maps stored in the road map storage units B113b and B113a may have different levels of accuracy, both the road map storage units B113b and B113a employ maps with accuracy that is compatible with satellite positioning based on a GNSS in the present embodiment. Additionally, the road map stored in the road map storage unit B113b includes the position information of roadside buildings RB and the position information of the median strip of the road R similarly to the road map stored in the road map storage unit B113a.

[0120] Note that the road maps stored in the road map storage unit B113b and the road map storage unit B113a can be updated to the latest road map saved in a remote server by causing the straight traveling vehicle VB and the right turning vehicle VA to communicate with the remote server, or the road maps can be updated to the latest road map saved in a portable storage medium (storage device) that saves the latest road map by connecting the storage medium to the straight traveling vehicle VB and the right turning vehicle VA.

[0121] The right turn intention detection unit B114b is adapted to detect a right turn intention of the right turning vehicle VA, and the detection of the right turn intentin is based on reading of information indicating an operating status of the right turn signal from vehicle information acquired from the right turning vehicle VA via the receiver 122b or identification of the link ID of the lane where the right turning vehicle VA is present from the current position Pa of the right turning vehicle VA in a case where the right turning vehicle VA turns right at the intersection CS. It is also possible to include the link IDs of the lanes where the vehicles VA and VB are present in vehicle information exchanged between the straight traveling vehicle VB and the right turning vehicle VA and to detect the right turn intention of the right turning vehicle VA on the basis of the link IDs acquired through communication.

[0122] The vehicle speed detection unit B115b is adapted to detect the vehicle speed VSPa of the right turning vehicle VA, and the detection thereof is based on reading of vehicle speed information indicating the vehicle speed VSPa from vehicle information acquired from the right turning vehicle VA via the receiver 122b.

[0123] The first vehicle behavior detection unit B116b detects that the right turning vehicle VA is located at a predetermined relative position with reference to the first predetermined position P1 relative to the intersection CS after showing its right turn intention. Specifically, the first vehicle behavior detection unit B116b compares the current position Pa of the right turning vehicle VA on the road map with the intersection area ACS and detects that the right turning vehicle VA has arrived at the intersection area ACS or has entered the intersection area ACS similarly to the above description. Then, the first vehicle behavior detection unit B116b sets a timing at which any of these behaviors of the right turning vehicle VA is detected as a first notification issuance timing. The first notification issuance timing set by the first vehicle behavior detection unit B116b is a timing at which the straight traveling vehicle VB performs notification issuance in the first predetermined mode.

[0124] The size and the shape of the intersection area ACS may be the same or different between the controller 101a of the right turning vehicle VA and the controller 101b of the straight traveling vehicle. It is possible to set the size of the intersection area ACS to be variable or to change the shape thereof in accordance with a drivers' selection or trends of driving states at the time of passing the intersection CS, for example.

[0125] The second vehicle behavior detection unit B117b monitors a behavior of the right turning vehicle VA after the right turning vehicle VA enters the intersection CS and detects that the right turning vehicle VA is traveling toward the predicted collision point CPP in the intersection area ACS or is present inside the predicted collision area ACP after entering the intersection area ACS. Then, the second vehicle behavior detection unit B117b sets a timing at which any of these behaviors of the right turning vehicle VA is detected as a second notification issuance timing. The second notification issuance timing set by the second vehicle behavior detection unit B117b is a timing at which the straight traveling vehicle VB performs notification issuance in the second predetermined mode.

[0126] Although the size and the shape of the predicted collision area ACP may be different between the controller 101a and the controller 101b, similar setting is adopted for both in the present embodiment. The predicted collision area ACP may be preset as default coordinates on the road map, or coordinate information of the predicted collision area ACP set in one of the controllers 101a and 101b may be provided to and set in the other controller through vehicle-to-vehicle communication.

[0127] The first notification issuing unit B118b outputs a command signal to issue the notification in the first predetermined mode to the HMI device 131b included in the host vehicle (that is, the straight traveling vehicle VB) under a condition that the first predetermined notification issuance condition related to the position Pb of the straight traveling vehicle VB is established at a timing at which the arrival of the right turning vehicle VA at the intersection area ACS or entrance thereof to the intersection area ACS is detected, that is, at the first notification issuance timing. Similarly to the above description, the first predetermined notification issuance condition is that the straight traveling vehicle VB is located at the information presentation distance Dth1 from the intersection CS or is present at a position closer to the intersection CS than the information presentation distance Dth1. The output of the command signal to perform the notification issuance in the first predetermined mode from the first notification issuing unit B118b to the HMI device 131b is regarded as "execution of the notification issuance in the first predetermined mode".

[0128] The HMI device 131b that has received the command signal from the first notification issuing unit B118b issues a notification to promote the driver of the straight traveling vehicle VB to recognize that the right turning vehicle VA which the driver should pay attention to is present in the right turn lane L11 in the opposite lanes using display and sound. Similarly to the above description, the notification issuance performed by the first notification issuing unit B118b is notification issuance to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA.

[0129] The second notification issuing unit B119b outputs the command signal to perform the notification issuance in the second predetermined mode, which is a command signal to issue a notification in the second predetermined mode, to the HMI device 131b under a condition that the second predetermined notification issuance condition related to the position Pb of the straight traveling vehicle VB is established at a timing at which traveling of the right turning vehicle VA toward the predicted collision point CPP in the intersection area ACS or presence thereof inside the predicted collision area ACP is detected, that is, at the second notification issuance timing. The second predetermined notification issuance condition is that the straight traveling vehicle VB is located at the alarm distance Dth2 from the intersection CS or is present at a position closer to the intersection CS than the alarm distance Dth2. The output of the command signal to perform the notification issuance in the second predetermined mode from the second notification issuing unit B119b to the HMI device 131b is regarded as "execution of the notification issuance in the second predetermined mode".

[0130] The HMI device 131b that has received the command signal from the second notification issuing unit B119b issues a notification to promote the driver of the straight traveling vehicle VB to recognize higher urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA using display and sound. Similarly to the above description, the notification issuance performed by the second notification issuing unit B119a is also notification issuance that is more prominent and more visually or auditorily appealing to the driver.

[0131] The information presentation distance Dth1 and the alarm distance Dth2 may be set to equal distances between the controller 101a and the controller 101b or may be set to different distances therebetween. For example, a deceleration degree when the straight traveling vehicle VB has actually decelerated in response to an alarm is learned, and the deceleration degrees used when the distances Dth1 and Dth2 are calculated are corrected on the basis of a learned value that indicates the actual deceleration degree. Specifically, in a case where the actual deceleration in response to an alarm tends to be slow as compared with the case of the deceleration degree DEC2, the deceleration degrees DEC1 and DEC2 are corrected to decrease, such that the notification issuance for each of the information presentation and the alarm can be performed at an earlier timing.

[0132] The first notification issuing unit B118b and the second notification issuing unit B119b can also notify the right turning vehicle VA of the fact that the notification in each mode (the notification issuance in the first predetermined mode and the notification issuance in the second predetermined mode) has been issued via the transmitter 121b in accordance with the output of the command signal to the HMI device 131b.

[0133] The third vehicle behavior detection unit B120b detects that the right turning vehicle VA is present at a predetermined position relative to the virtual intersection VCS. Specifically, the third vehicle behavior detection unit B120b compares the current position Pa of the right turning vehicle VA on the road map with the virtual intersection area VACS and detects that the right turning vehicle VA has arrived at the virtual intersection area VACS or has entered the virtual intersection area VACS similarly to the above description. Then, the third vehicle behavior detection unit B120b sets a timing at which any of these behaviors of the right turning vehicle VA is detected as a third notification issuance timing. The third notification issuance timing set by the third vehicle behavior detection unit B120b is a timing at which the straight traveling vehicle VB performs notification issuance in the third predetermined mode.

[0134] The size and the shape of the virtual intersection area VACS may be the same or different between the controller 101a and the controller 101b. It is possible to set the size of the virtual intersection area VACS to be variable or to change the shape thereof in accordance with a drivers' selection or trends of driving states at the time of passing the virtual intersection VCS, for example.

[0135] The fourth vehicle behavior detection unit B121b monitors a behavior of the right turning vehicle VA after the setting of the third notification issuance timing. In other words, the fourth vehicle behavior detection unit B121b monitors a behavior of the right turning vehicle VA after entering the virtual intersection area VACS. The fourth vehicle behavior detection unit B121b detects whether the right turning vehicle VA is traveling toward the virtual predicted collision point VCPP inside the virtual intersection area VACS or is present inside the virtual predicted collision area VACP on the basis of the current position Pa of the right turning vehicle VA on the road map. Then, the fourth vehicle behavior detection unit B121b sets the timing at which any of these behaviors of the right turning vehicle VA is detected as a fourth notification issuance timing. The fourth notification issuance timing set by the fourth vehicle behavior detection unit B121b is a timing at which the straight traveling vehicle VB performs notification issuance in the fourth predetermined mode.

[0136] Although the size and the shape of the virtual predicted collision area VACP may be different between the controller 101a of the right turning vehicle and the controller 101b of the straight traveling vehicle, similar setting is adopted for both in the present embodiment. The virtual predicted collision area VACP may be set to have the same size and shape in each of the controller 101a and the controller 101b, or coordinate information of the virtual predicted collision area VACP set in one of the controllers 101a and 101b may be provided to and set in the other controller through vehicle-to-vehicle communication.

[0137] The first notification issuing unit B118b outputs a command signal to perform the notification issuance in the third predetermined mode to the HMI device 131b included in the host vehicle (that is, the straight traveling vehicle VB) under the condition that a third predetermined notification issuance condition defined in advance in regard to the position Pb of the straight traveling vehicle VB, is met at the third notification issuance timing set by the third vehicle behavior detection unit B120b. Similarly to the above description, the third predetermined notification issuance condition is that the straight traveling vehicle VB is present at the information presentation distance Dth3 from the virtual intersection VCS or at a position closer to the virtual intersection VCS than the information presentation distance Dth3. The output of the command signal to perform the notification issuance in the third predetermined mode from the first notification issuing unit B118b to the HMI device 131b is regarded as "execution of the notification issuance in the third predetermined mode".

[0138] The HMI device 131b that has received the command signal to perform the notification issuance in the third predetermined mode from the first notification issuing unit B118b issues a notification to promote the driver of the straight traveling vehicle VB to recognize that the right turning vehicle VA which the driver should pay attention to is present in the lane L11, which is an opposite lane, using display and sound. Similarly to the above description, the notification issuance performed by the first notification issuing unit B118b is notification issuance to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA.

[0139] The second notification issuing unit B119b outputs a command signal to issue a notification in a fourth predetermined mode to the HMI device 131b under a condition that a fourth predetermined notification issuance condition defined in advance in regard to the position Pb of the straight traveling vehicle VB is established at the fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a. Similarly to the above description, the fourth predetermined notification issuance condition is that the straight traveling vehicle VB is present at the alarm distance Dth4 from the virtual intersection VCS or at a position closer to the virtual intersection VCS than the alarm distance Dth4.

[0140] The HMI device 131b that has received the command signal to perfomr the notification issuance in the fourth predetermined mode from the second notification issuing unit B119b issues a notification to promote the driver of the straight traveling vehicle VB to recognize higher urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA using display and sound. Similarly to the above description, the notification issuance performed by the second notification issuing unit B119b is also notification issuance that is more prominent and more visually or auditorily appealing to the driver.

[0141] The first notification issuing unit B118b and the second notification issuing unit B119b can also provide a notification that the notification issuance in each mode (the notification issuance in the third predetermined mode and the notification issuance in the fourth predetermined mode) has been performed to the right turning vehicle VA via the transmitter 121b together with the output of the command signal to the HMI device 131b.

[0142] The information presentation distance Dth3 and the alarm distance Dth4 may be set to equal distances between the controller 101a and the controller 101b or may be set to different distances therebetween. For example, a deceleration degree when the straight traveling vehicle VB has actually decelerated in response to an alarm is learned, and the deceleration degrees used when the distances Dth3 and Dth4 are calculated are corrected on the basis of a learned value that indicates the actual deceleration degree. Specifically, in a case where the actual deceleration in response to an alarm tends to be slow as compared with the case of the deceleration degree DEC4, the deceleration degrees DEC3 and DEC4 are corrected to decrease, such that the notification issuance for each of the information presentation and the alarm can be performed at an earlier timing.

[0143] Similarly to the above description, the virtual area setting unit B122b sets the virtual intersection area VACS and the virtual predicted collision area VACP in an associated manner on the road map in a case where the right turning vehicle VA is present in the traveling lane L11 while the straight traveling vehicle VB is present in the opposite lane L22 and the right turn intention of the right turning vehicle VA. Specifically, the virtual area setting unit B122b sets the virtual intersection area VACS and the virtual predicted collision area VACP on the map in the specific range or the specific section extracted by the road map storage unit B113a. The right turning path TRa' of the right turning vehicle VA, which used in setting the virtual intersection area VACS and the virtual predicted collision area VACP, is set by the virtual area setting unit B122b in the same manner as described above.

[0144] Similarly to the above description, the first notification issuing unit B118b may not output the command signal to perform the notification issuance in the third predetermined mode, and the second notification issuing unit B119b may not output the command signal to perform the notification issuance in the fourth predetermined mode in a case where the right turning vehicle VA enters the intersection area ACS. Also, the virtual area setting unit B122b may not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB exceeds the predetermined separation distance Dth5, which is a relatively long distance, similarly to the above description. Other preferred aspects related to the virtual area setting unit B122b are similar to other preferred aspects related to the virtual area setting unit B122a, and description thereof will thus be omitted.(Content of Notification Control in Right Turning Vehicle Turning Right at Intersection)

[0145] Figs. 4 to 6 are flowcharts illustrating content of notification control performed by the controller 101a included in the right turning vehicle VA in a case where the right turning vehicle VA turns right at the intersection CS. The flowchart in Fig. 4 illustrates an overall flow of the notification control, the flowchart in Fig. 5 illustrates content of processing (information presentation processing) executed by the right turning vehicle VA in regard to information presentation, and the flowchart in Fig. 6 illustrates content of processing (alarm processing) executed by the right turning vehicle VA in regard to an alarm. The information presentation processing and the alarm processing are performed as parts of the notification control. The controller 101a performs the notification control every predetermined time in a case where an intersection CS is detected in a road R in front of the host vehicle (that is, the right turning vehicle VA).

[0146] In the flowchart illustrated in Fig. 4, the controller 101a read various kinds of control information used for the notification control in S111. The control information read in S111 includes the current position Pa, the vehicle speed VSPa, and the link ID of the right turning vehicle VA, which is a host vehicle, and the current position Pb, the vehicle speed VSPb, and the link ID of the straight traveling vehicle VB, which is another vehicle. The control information may include information regarding operating statuses of the right turn signals in the right turning vehicle VA and the straight traveling vehicle VB.

[0147] In S112, the controller 101a determines whether the right turning vehicle VA has detected the straight traveling vehicle VB in the straight direction toward the intersection CS in the lane L22 opposite to the lane L11 in which the right turning vehicle VA is present. The detection of the straight traveling vehicle VB is based on the link ID of straight traveling vehicle VB. The processing proceeds to S113 in a case where the straight traveling vehicle VB is detected, or this control is ended in a case where the straight traveling vehicle VB is not detected.

[0148] In S113, the controller 101a determines whether a right turn intention of the right turning vehicle VA has been detected. The detection of the right turn intention is based on an operating status of the right turn signal of the right turning vehicle VA. Additionally or alternatively, it is also possible to make the determination on the basis of the link ID of the right turning vehicle VA. In a case where the right turn lane L11 is a lane only for right turn, for example, the right turn intention of the right turning vehicle VA may also be detected by the fact that the lane where the right turning vehicle VA is traveling is the right turn lane L11. The processing proceeds to S114 in a case where the right turn intention is detected, or this control is ended in a case where the right turn intention is not detected.

[0149] In S114, the controller 101a specifies the current position Pa of the right turning vehicle VA on the road map.

[0150] In S115, the controller 101a determines whether the right turning vehicle VA has entered the intersection area ACS. In a case where the right turning vehicle VA is located at a position of the outer edge of the intersection area ACS (that is, the first predetermined position P1) or is located at a position closer to the intersection center CTR than the position of the outer edge, and the right turning vehicle VA has entered the intersection area ACS, the processing proceeds to S116. On the other hand, in a case where the right turning vehicle VA has not entered the intersection area ACS and is located at a position farther from the intersection center CTR than the outer edge of the intersection area ACS, this control is ended.

[0151] In S116, the controller 101a performs the information presentation processing. The information presentation processing follows a procedure illustrated in the flowchart in Fig. 5.

[0152] In S117, the controller 101a performs the alarm processing. The alarm processing follows a procedure illustrated in the flowchart in Fig. 6.

[0153] In S118, the controller 101a determines whether the right turning vehicle VA has passed the intersection CS. The determination of whether the right turning vehicle VA has passed the intersection CS is made based on the fact that the right turning vehicle VA has left the intersection area ACS in the traveling direction after turning right. This control is ended in a case where the right turning vehicle VA has passed the intersection CS, or the processing returns to S116 to repeat the information presentation processing and the alarm processing until the right turning vehicle VA passes the intersection area ACS in a case where the right turning vehicle VA has not passed the intersection CS and is still in the intersection area ACS.

[0154] In the flowchart illustrated in Fig. 5, the controller 101a reads various kinds of control information used for the information presentation processing in S211. The control information read in S211 includes the current position Pa and the vehicle speed VSPa of the right turning vehicle VA and the current position Pb and the vehicle speed VSPb of the straight traveling vehicle VB.

[0155] In S212, the controller 101a specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map.

[0156] In S213, the controller 101a determines whether the right turning vehicle VA is located outside the predicted collision area ACP. _In a case where the right turning vehicle VA is located between the position of the outer edge of the intersection area ACS and the position of the outer edge of the predicted collision area ACP (that is, the second predetermined position P2) and is located outside the predicted collision area ACP, the processing proceeds to S214. When using the operating status of the right turn signal in order to detect the right turn intention of the right turning vehicle VA, the controller 101a may determine whether the operation of the right turn signal is being continued in addition to the processing in S213 and perform the processing in and after S214 in a case where the operation of the right turn signal is being continued. On the other hand, in a case where the right turning vehicle VA is located at the outer edge of the predicted collision area ACP or a position closer to the predicted collision point CPP than the outer edge and is not located outside the predicted collision area ACP, the information presentation processing is ended.

[0157] In S214, the controller 101a reads the vehicle speed VSPa of the right turning vehicle VA.

[0158] In S215, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than a predetermined vehicle speed VSP1. The predetermined vehicle speed VSP1 is a low speed that is low enough to determine that the right turning vehicle VA is in a low-speed traveling state and is a reduced speed (specifically, 10 km / hour), for example. In the present embodiment, it is determined that the driver of the right turning vehicle VA is paying attention to the surrounding situation to pass the intersection CS by the fact that the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. The processing proceeds to S216 in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, or the information presentation processing is ended in a case where the vehicle speed VSPa is greater than the vehicle speed VSP1. The predetermined vehicle speed VSP1 may be 0 km / hour, and in other words, S215 may be processing of determining whether the right turning vehicle VA has temporarily stopped inside the intersection area ACS. Furthermore, it is also possible to eliminate the processing in S215 itself, and the notification issuance for an alarm may be prioritized over the notification issuance for the information presentation in a case where a notification issuance condition for the information presentation (S220) and the notification issuance condition for the alarm (S320) are established at the same time.

[0159] In this manner, in a case where the right turning vehicle VA has maintained the low vehicle speed VSPa until the arrival at the predicted collision area ACP or has sufficiently decelerated (including the case of temporarily stopping) after entering the intersection area ACS, the controller 101a of the present embodiment determines that a notification issuance timing for the information presentation (that is, the first notification issuance timing) has arrived on the basis of the detection of the vehicle speed VSPa that is equal to or less than the predetermined vehicle speed VSP1, performs the processing in and after S216 is performed, and determines whether the first predetermined notification issuance condition has been established. The notification issuance timing for the information presentation is not limited thereto, and it is possible to set the notification issuance timing for the information presentation on the basis of the entrance of the right turning vehicle VA to the intersection area ACS, in other words, on the basis of the right turning vehicle VA being located inside the intersection area ACS, without providing any limitations based on a driving state such as the vehicle speed VSPa.

[0160] In S216, the controller 101a calculates the distance from intersection CS to the straight traveling vehicle VB, in other words, a distance Db remaining in front of the straight traveling vehicle VB until arriving at the intersection CS (hereinafter, referred to as an "intersection arrival distance"). As illustrated in Fig. 12, the intersection arrival distance Db is calculated as the distance from the outer edge of the predicted collision area ACP to the straight traveling vehicle VB, and the calculation is based on the current position Pb of the straight traveling vehicle VB.

[0161] In S217, the controller 101a reads the vehicle speed VSPb of the straight traveling vehicle VB.

[0162] In S218, the controller 101a calculates the information presentation distance Dth1. The calculation of the information presentation distance Dth1 is based on the vehicle speed VSPb of the straight traveling vehicle VB and the first predetermined deceleration degree DEC1 as described above.

[0163] In S219, the controller 101a determines whether the intersection arrival distance Db of the straight traveling vehicle VB is equal to or less than the information presentation distance Dth1, in other words, whether the straight traveling vehicle VB is located at the information presentation distance Dth1 from the intersection CS or is located at a position closer to the intersection CS than the information presentation distance Dth1. The processing proceeds to S220 in a case where the intersection arrival distance Db is equal to or less than the information presentation distance Dth1, or the information presentation processing is ended in a case where the intersection arrival distance Db is greater than the information presentation distance Dth1.

[0164] In S220, the controller 101a performs notification issuance for information presentation.

[0165] In the flowchart illustrated in Fig. 6, the controller 101a reads various kinds of control information used for the alarm processing in S311. The control information read in S311 includes the current position Pa and the vehicle speed VSPa of the right turning vehicle VA and the current position Pb and the vehicle speed VSPb of the straight traveling vehicle VB.

[0166] In S312, the controller 101a specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map.

[0167] In S313, the controller 101a determines whether the right turning vehicle VA is located inside the predicted collision area ACP. In a case where the right turning vehicle VA is located at the position of the outer edge of the predicted collision area ACP (that is, the second predetermined position P2) or is located at the position closer to the predicted collision point CPP than the position of the outer edge and the right turning vehicle VA is located inside the predicted collision area ACP, the processing proceeds to S316. On the other hand, in a case where the right turning vehicle VA is located at a position farther from the predicted collision point CPP than the outer edge of the predicted collision area ACP and is not located inside the predicted collision area ACP, the processing proceeds to S314. In a case where the operating status of the right turn signal is used to detect the right turn intention of the right turning vehicle VA, the fact that the operation of the right turn signal is being continued may be included as a condition of performing the processing as a premise of performing the processing in S313.

[0168] In S314, the controller 101a reads the vehicle speed VSPa of the right turning vehicle VA.

[0169] In S315, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is higher than the predetermined vehicle speed VSP1. The processing proceeds to S316 in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1, or the alarm processing is ended in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. In other words, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is greater than the vehicle speed VSP1 achieved in the low-speed traveling state, for example, a speed reduced state, and in a case where the vehicle speed VSPa is greater than the vehicle speed VSP1, the controller 101a determines that the driver of the right turning vehicle VA is not paying attention to the surrounding situation, and the processing proceeds to S316. On the other hand, in a case where the vehicle speed VSPa is equal to or less than the vehicle speed VSP1, the controller 101a determines that the notification should be issued for the information presentation in the situation and ends the alarm processing.

[0170] In this manner, the controller 101a determines that a notification issuance timing for an alarm (that is, the second notification issuance timing) has arrived on the basis of detection of a situation in which the right turning vehicle VA has arrived at the predicted collision area ACP and has already been in the predicted collision area ACP after entering the intersection area ACS or the right turning vehicle VA is traveling at a speed that is equal to or greater than a specific speed toward the predicted collision point CPP even outside the predicted collision area ACP and is approaching the predicted collision area ACP in S313 to S315, performs the processing in and after S316, and determines whether the second predetermined notification issuance condition is established.

[0171] In S316, the controller 101a calculates the intersection arrival distance Db of the straight traveling vehicle VB.

[0172] In S317, the controller 101a reads the vehicle speed VSPb of the straight traveling vehicle VB.

[0173] In S318, the controller 101a calculates the alarm distance Dth2. The calculation of the alarm distance Dth2 is based on the vehicle speed VSPb of the straight traveling vehicle VB and the second predetermined deceleration degree DEC2 as described above.

[0174] In S319, the controller 101a determines whether the intersection arrival distance Db of the straight traveling vehicle VB is equal to or less than the alarm distance Dth2, in other words, whether the straight traveling vehicle VB is located at the alarm distance Dth2 from the intersection CS or is located at a position closer to the intersection CS than the alarm distance Dth2. The processing proceeds to S320 in the case where the intersection arrival distance Db is equal to or less than the alarm distance Dth2, or the alarm processing is ended in a case where the intersection arrival distance Db is greater than the alarm distance Dth2.

[0175] In S320, the controller 101a performs the notification issuance for the alarm.(Content of Notification Control in Straight Traveling Vehicle Traveling straight across Intersection)

[0176] Figs. 7 to 9 are flowcharts illustrating content of notification control performed by the controller 101b included in the straight traveling vehicle VB when the straight traveling vehicle VB travels straight across the intersection CS. The flowchart in Fig. 7 illustrates an overall flow of the notification control, the flowchart in Fig. 8 illustrates content of the information presentation processing executed by the straight traveling vehicle VB, and the flowchart in Fig. 9 illustrates content of the alarm processing executed by the straight traveling vehicle VB. The controller 101b performs the notification control every predetermined time in a case where an intersection CS is detected in a road R in front of the host vehicle. The execution cycles of the notification control may be the same or different between the controller 101a and the controller 101b. Furthermore, both the controllers 101a and 101b can also perform the notification control in a synchronized manner.

[0177] Each process performed by the controller 101a and the controller 101b in regard to the notification control at the intersection CS corresponds to each other. Therefore, detailed description of the processes that are similar for both will be omitted in the following description.

[0178] In the flowchart illustrated in Fig. 7, the controller 101b read various kinds of control information used for the notification control (S411), detects another vehicle that is present in the right turn lane L11 in the opposite lanes, that is, the right turning vehicle VA (S412), and then determines whether the right turn intention of the right turning vehicle VA, which is another vehicle, has been detected in S413. After detecting the right turn intention, the controller 101b specifies the current position Pa of the right turning vehicle VA on the road map (S414), and determines whether the right turning vehicle VA has entered the intersection area ACS (S415). The controller 101b executes the procedure in and after S416 in a case where the right turning vehicle VA has entered the intersection area ACS, or ends this control in a case where the right turning vehicle VA has not entered the intersection area ACS. The controller 101b executes the information presentation processing in S416 and the alarm processing in S417. The information presentation processing and the alarm processing are repeated until the right turning vehicle VA passes the intersection area ACS.

[0179] In the flowchart illustrated in Fig. 8, the controller 101b reads various kinds of control information used for the information presentation processing, such as the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA (S511), and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map (S512). In S513, the controller 101b determines whether the right turning vehicle VA, which is another vehicle, is located outside the predicted collision area ACP, reads the vehicle speed VSPa of the right turning vehicle VA (S514) in a case where the controller 101b determines that the right turning vehicle VA is located outside the predicted collision area ACP, and determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the predetermined vehicle speed VSP1 (S515). The controller 101b performs the processing in and after S516 in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, or ends the information presentation processing in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1. When using the operating status of the right turn signal in order to detect the right turn intention of the right turning vehicle VA, the controller 101b may determine whether the operation of the right turn signal is being continued in addition to the processing in S513, and execute the processing in and after S514 in a case where the operation of the right turn signal is being continued. Then, the controller 101b calculates the intersection arrival distance Db of the straight traveling vehicle VB, which is the host vehicle (S516), reads the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) (S517), and calculates the information presentation distance Dth1 (S518). The processing proceeds to S520 to issue a notification for information presentation in a case where the intersection arrival distance Db is equal to or less than the information presentation distance Dth1 (S519), or the information presentation processing is ended in a case where the intersection arrival distance Db is greater than the information presentation distance Dth1.

[0180] In the flowchart illustrated in Fig. 9, the controller 101b reads various kinds of control information used for the alarm processing such as the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA (S611), and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map are (S612). The controller 101b determines whether the right turning vehicle VA, which is another vehicle, is located inside the predicted collision area ACP, in S613, reads the vehicle speed VSPa of the right turning vehicle VA (S614) in a case where the right turning vehicle VA is determined not to be located inside the predicted collision area ACP, and determines whether the vehicle speed VSPa of the right turning vehicle VA is greater than the predetermined vehicle speed VSP1 (S615). The controller 101b performs the processing in and after S616 in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1, or ends the alarm processing in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. In a case where the operating status of the right turn signal is used to detect the right turn intention of the right turning vehicle VA, the fact that the operation of the right turn signal is being continued may be included in the condition of performing the processing as a premise of performing the processing in S613. Then, the controller 101b calculates the intersection arrival distance Db of the straight traveling vehicle VB, which is a host vehicle (S616), reads the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) (S617), and calculates the alarm distance Dth2 (S618). The processing proceeds to S620 to issue a notification for the alarm in a case where the intersection arrival distance Db is equal to or less than the alarm distance Dth2, or the alarm processing is ended in a case where the intersection arrival distance Db is greater than the alarm distance Dth2.(Content of Notification Control in Right Turning Vehicle Turning Right at Virtual Intersection)

[0181] Figs. 15 to 17 are flowcharts illustrating content of notification control performed by the controller 101a included in the right turning vehicle VA in a case where the right turning vehicle VA turns right at the virtual intersection VCS. The flowchart in Fig. 15 illustrates an overall flow of the notification control, the flowchart in Fig. 16 illustrates content of processing (information presentation processing) executed by the right turning vehicle VA in regard to information presentation, and the flowchart in Fig. 17 illustrates content of processing (alarm processing) executed by the right turning vehicle VA in regard to an alarm. The information presentation processing and the alarm processing are performed as parts of the notification control. The controller 101a performs the notification control every predetermined time.

[0182] In the present embodiment, the controller 101a can process the aforementioned notification control for the right turning vehicle VA turning right at the intersection CS and the notification control for the right turning vehicle VA turning right at the virtual intersection VCS in parallel. For convenience of explanation, it is assumed that the right turning vehicle VA does not enter the intersection area ACS in the notification control illustrated in Figs. 15 to 17 and Figs. 18 to 20, which will be described later.

[0183] In the flowchart illustrated in Fig. 15, the controller 101a read various kinds of control information used for the notification control in S1111. The control information read in S1111 includes the current position Pa, the vehicle speed VSPa, and the link ID of the right turning vehicle VA, which is a host vehicle, and the operating statuses of the right turn signals in the right turning vehicle VA, and the current position Pb, the vehicle speed VSPb, and the link ID of the straight traveling vehicle VB, which is another vehicle, and the operating statuses of the right turn signals in the straight traveling vehicle VB. The control information read in S1111 may include the steering information and the destination information of the right turning vehicle VA, and the steering information and the destination information of the straight traveling vehicle VB.

[0184] In S1112, the controller 101a determines whether the right turning vehicle VA has detected the straight traveling vehicle VB in the straight direction in the lane L22 opposite to the lane L11 in which the right turning vehicle VA is present. The detection of the straight traveling vehicle VB is based on the link ID of straight traveling vehicle VB. The processing proceeds to S113 in a case where the straight traveling vehicle VB is detected, or this control is ended in a case where the straight traveling vehicle VB is not detected. In a case where the straight traveling vehicle VB is detected in S1112, the condition that the right turning vehicle VA is present in the lane 11 and the straight traveling vehicle VB is present in the opposite lane L22 is established.

[0185] In S1113, the controller 101a determines whether a right turn intention of the right turning vehicle VA has been detected. The detection of the right turn intention is based on an operating status of the right turn signal of the right turning vehicle VA. The processing proceeds to S1114 in a case where the right turn intention is detected, or this control is ended in a case where the right turn intention is not detected.

[0186] In S1114, the controller 101a determines whether the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB is equal to or less than the predetermined separation distance Dth5. The distance Dab between the right turning vehicle VA and the straight traveling vehicle VB is based on the current position Pa of the right turning vehicle VA and the current position Pb of the straight traveling vehicle VB. The processing proceeds to S1115 in a case where the distance Dab is equal to or less than the predetermined separation distance Dth5, or this control is ended in a case where the distance Dab is not equal to or less than the predetermined separation distance Dth5. Not that it is also possible to eliminate the processing in S1114 itself.

[0187] In S1115, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the second predetermined vehicle speed VSP2 that is a vehicle speed higher than the first predetermined vehicle speed VSP1. The processing proceeds to S1116 in a case where the vehicle speed VSPa is equal to or less than a the second predetermined vehicle speed VSP2, or this control is ended in a case where the vehicle speed VSPa is not equal to or less than the second predetermined vehicle speed VSP2. Not that it is also possible to eliminate the processing in S1115 itself.

[0188] In S1116, the controller 101a sets the virtual intersection area VACS and the virtual predicted collision area VACP. As described above, the virtual intersection area VACS and the virtual predicted collision area VACP are based on the right turning path TRa', which is a path where the right turning vehicle VA travels when the right turning vehicle VA turns right at the virtual intersection VCS. The processing of setting the right turning path TRa' and its explanation are omitted.

[0189] In S1117, the controller 101a specifies the current position Pa of the right turning vehicle VA on the road map.

[0190] In S1118, the controller 101a determines whether the right turning vehicle VA has entered the virtual intersection area VACS. In a case where the right turning vehicle VA is located at a position of the outer edge of the virtual intersection area VACS or is located at a position closer to the virtual intersection center VCTR than the position of the outer edge, and the right turning vehicle VA has entered the virtual intersection area VACS, the processing proceeds to S116. On the other hand, in a case where the right turning vehicle VA has not entered the virtual intersection area VACS and is located at a position farther from the virtual intersection VCTR than the outer edge of the virtual intersection area VACS, this control is ended.

[0191] In S1119, the controller 101a performs the information presentation processing. The information presentation processing follows a procedure illustrated in the flowchart in Fig. 16.

[0192] In S1120, the controller 101a performs the alarm processing. The alarm processing follows a procedure illustrated in the flowchart in Fig. 6.

[0193] In S1121, the controller 101a determines whether the right turning vehicle VA has passed the virtual intersection VCS. The determination of whether the right turning vehicle VA has passed the virtual intersection VCS is made based on the fact that the right turning vehicle VA has left the virtual intersection area VACS in the traveling direction after turning right. This control is ended in a case where the right turning vehicle VA has passed the virtual intersection VCS, or the processing returns to S1119 to repeat the information presentation processing and the alarm processing until the right turning vehicle VA passes the virtual intersection area VACS in a case where the right turning vehicle VA is still in the virtual intersection area VACS and has not passed the virtual intersection VCS.

[0194] In the flowchart illustrated in Fig. 16, the controller 101a reads various kinds of control information used for the information presentation processing in S1211. The control information read in S1211 includes the current position Pa and the vehicle speed VSPa of the right turning vehicle VA and the current position Pb and the vehicle speed VSPb of the straight traveling vehicle VB.

[0195] In S1212, the controller 101a specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map.

[0196] In S1213, the controller 101a determines whether the right turning vehicle VA is located outside the virtual predicted collision area VACP. _In a case where the right turning vehicle VA is located between the position of the outer edge of the virtual intersection area VACS and the position of the outer edge of the virtual predicted collision area VACP and is located outside the virtual predicted collision area VACP, the processing proceeds to S1214. On the other hand, in a case where the right turning vehicle VA is located at the outer edge of the virtual predicted collision area VACP or a position closer to the virtual predicted collision point VCPP than the outer edge and is not located outside the virtual predicted collision area VACP, the information presentation processing is ended. Note that the controller 101a may determine whether the operation of the right turn signal, which is used to detect the right turn intention of the right turning vehicle VA, is being continued in addition to the processing in S1213 and perform the processing in and after S1214 in a case where the operation of the right turn signal is being continued.

[0197] In S1214, the controller 101a reads the vehicle speed VSPa of the right turning vehicle VA.

[0198] In S1215, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than a predetermined vehicle speed VSP1. The predetermined vehicle speed VSP1 is as described in S215. In the present embodiment, it is determined that the driver of the right turning vehicle VA is paying attention to the surrounding situation to pass the virtual intersection VCS by the fact that the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. The processing proceeds to S1216 in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, or the information presentation processing is ended in a case where the vehicle speed VSPa is greater than the vehicle speed VSP1. The predetermined vehicle speed VSP1 may be 0 km / hour, and in other words, S1215 may be processing of determining whether the right turning vehicle VA has temporarily stopped inside the intersection area ACS. Furthermore, it is also possible to eliminate the processing in S1215 itself, and the notification issuance for an alarm may be prioritized over the notification issuance for the information presentation in a case where a notification issuance condition for the information presentation (S1220) and the notification issuance condition for the alarm (S1320) are established at the same time.

[0199] In this manner, in a case where the right turning vehicle VA has maintained the low vehicle speed VSPa until the arrival at the virtual predicted collision area VACP or has sufficiently decelerated (including the case of temporarily stopping) after entering the virtual intersection area VACS, the controller 101a of the present embodiment determines that a notification issuance timing for the information presentation (that is, the third notification issuance timing) has arrived on the basis of the detection of the vehicle speed VSPa that is equal to or less than the predetermined vehicle speed VSP1, performs the processing in and after S1216, and determines whether the third predetermined notification issuance condition has been established. The notification issuance timing for the information presentation is not limited thereto, and it is possible to set the notification issuance timing for the information presentation on the basis of the entrance of the right turning vehicle VA to the virtual intersection area VACS, in other words, on the basis of the right turning vehicle VA being located inside the virtual intersection area VACS, without providing any limitations based on a driving state such as the vehicle speed VSPa.

[0200] In S216, the controller 101a calculates the distance from virtual intersection VCS to the straight traveling vehicle VB, in other words, a distance Db' remaining in front of the straight traveling vehicle VB until arriving at the virtual intersection VCS (hereinafter, referred to as a "virtual intersection arrival distance"). As illustrated in Fig. 22, the virtual intersection arrival distance Db' is calculated as the distance from the outer edge of the virtual predicted collision area VACP to the straight traveling vehicle VB, and the calculation is based on the current position Pb of the straight traveling vehicle VB.

[0201] In S1217, the controller 101a reads the vehicle speed VSPb of the straight traveling vehicle VB.

[0202] In S1218, the controller 101a calculates the information presentation distance Dth3. The calculation of the information presentation distance Dth3 is based on the vehicle speed VSPb (= V1') of the straight traveling vehicle VB and the first predetermined deceleration degree DEC3, and is specifically based on the equation (3), as described above.

[0203] In S1219, the controller 101a determines whether the virtual intersection arrival distance Db' of the straight traveling vehicle VB is equal to or less than the information presentation distance Dth3, in other words, whether the straight traveling vehicle VB is located at the information presentation distance Dth3 from the virtual intersection VCS or is located at a position closer to the virtual intersection VCS than the information presentation distance Dth3. The processing proceeds to S1220 in a case where the virtual intersection arrival distance Db' is equal to or less than the information presentation distance Dth3, or the information presentation processing is ended in a case where the virtual intersection arrival distance Db' is greater than the information presentation distance Dth3.

[0204] In S1220, the controller 101a performs notification issuance for information presentation.

[0205] In the flowchart illustrated in Fig. 17, the controller 101a reads various kinds of control information used for the alarm processing in S1311. The control information read in S1311 includes the current position Pa and the vehicle speed VSPa of the right turning vehicle VA and the current position Pb and the vehicle speed VSPb of the straight traveling vehicle VB.

[0206] In S1312, the controller 101a specifies the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map.

[0207] In S1313, the controller 101a determines whether the right turning vehicle VA is located inside the virtual predicted collision area VACP. In a case where the right turning vehicle VA is located at the position of the outer edge of the virtual predicted collision area VACP or is located at the position closer to the virtual predicted collision point VCPP than the position of the outer edge and the right turning vehicle VA is located inside the virtual predicted collision area VACP, the processing proceeds to S1316. On the other hand, in a case where the right turning vehicle VA is located at a position farther from the virtual predicted collision point VCPP than the outer edge of the virtual predicted collision area VACP and is not located inside the virtual predicted collision area VACP, the processing proceeds to S1314. The fact that the operation of the right turn signal is being continued may be included as a condition of performing the processing as a premise of performing the processing in S1313.

[0208] In S1314, the controller 101a reads the vehicle speed VSPa of the right turning vehicle VA.

[0209] In S1315, the controller 101a determines whether the vehicle speed VSPa of the right turning vehicle VA is higher than the predetermined vehicle speed VSP1. The processing proceeds to S1316 in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1, or the alarm processing is ended in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1.

[0210] In this manner, the controller 101a determines that a notification issuance timing for an alarm (that is, the fourth notification issuance timing) has arrived on the basis of detection of a situation in which the right turning vehicle VA has arrived at the virtual predicted collision area VACP and has already been in the virtual predicted collision area VACP after entering the virtual intersection area VACS or the right turning vehicle VA is traveling at a speed that is equal to or greater than a specific speed toward the virtual predicted collision point VCPP even outside the virtual predicted collision area VACP and is approaching the virtual predicted collision area VACP in S1313 to S1315, performs the processing in and after S1316, and determines whether the second predetermined notification issuance condition is established.

[0211] In S1316, the controller 101a calculates the virtual intersection arrival distance Db' of the straight traveling vehicle VB.

[0212] In S1317, the controller 101a reads the vehicle speed VSPb of the straight traveling vehicle VB.

[0213] In S1318, the controller 101a calculates the alarm distance Dth4. The calculation of the alarm distance Dth4 is based on the vehicle speed VSPb (= V1') of the straight traveling vehicle VB and the fourth predetermined deceleration degree DEC4, and is specifically based on the equation (4), as described above.

[0214] In S1319, the controller 101a determines whether the virtual intersection arrival distance Db' of the straight traveling vehicle VB is equal to or less than the alarm distance Dth4, in other words, whether the straight traveling vehicle VB is located at the alarm distance Dth4 from the virtual intersection VCS or is located at a position closer to the virtual intersection VCS than the alarm distance Dth4. The processing proceeds to S1320 in the case where the virtual intersection arrival distance Db' is equal to or less than the alarm distance Dth4, or the alarm processing is ended in a case where the virtual intersection arrival distance Db' is greater than the alarm distance Dth4.

[0215] In S1320, the controller 101a performs the notification issuance for the alarm.(Content of Notification Control in Straight Traveling Vehicle Traveling straight across Virtual Intersection)

[0216] Figs. 18 to 20 are flowcharts illustrating content of notification control performed by the controller 101b included in the straight traveling vehicle VB when the straight traveling vehicle VB travels straight across the intersection CS. The flowchart in Fig. 18 illustrates an overall flow of the notification control, the flowchart in Fig. 19 illustrates content of the information presentation processing executed by the straight traveling vehicle VB, and the flowchart in Fig. 20 illustrates content of the alarm processing executed by the straight traveling vehicle VB. The controller 101b performs the notification control every predetermined time. The execution cycles of the notification control may be the same or different between the controller 101a and the controller 101b. Furthermore, both the controllers 101a and 101b can also perform the notification control in a synchronized manner.

[0217] In the present embodiment, the controller 101b can process the aforementioned notification control for the straight traveling vehicle VB traveling straight across the intersection CS and the notification control for the straight traveling vehicle VB traveling straight across the virtual intersection VCS in parallel.

[0218] Each process performed by the controller 101a and the controller 101b in regard to the notification control at the virtual intersection VCS corresponds to each other. Therefore, detailed description of the processes that are similar for both will be omitted in the following description.

[0219] In the flowchart illustrated in Fig. 18, the controller 101b read various kinds of control information used for the notification control (S1411), detects another vehicle that is present in the right turn lane L11 in the opposite lanes, that is, the right turning vehicle VA (S1412), and then determines whether the right turn intention of the right turning vehicle VA, which is another vehicle, has been detected in S1413. After detecting the right turn intention, the controller 101b determines whether the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB is equal to or less than the predetermined separation distance Dth5 in S1414, determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the second predetermined vehicle speed VSP2 in a case where the distance Dab is equal to or less than the predetermined separation distance Dth5 (S1415). In a case where the vehicle speed VSPa is equal to or less than the second predetermined vehicle speed VSP2, the controller 101b sets the virtual intersection area VACS and the virtual predicted collision area VACP (S1416), specifies the current position Pa of the right turning vehicle VA on the road map (S1417), and determines whether the right turning vehicle VA has entered the virtual intersection area VACS (S1418). The controller 101b executes the procedure in and after S1419 in a case where the right turning vehicle VA has entered the virtual intersection area VACS, or ends this control in a case where the right turning vehicle VA has not entered the virtual intersection area VACS. The controller 101b executes the information presentation processing in S1419 and the alarm processing in S1420. The information presentation processing and the alarm processing are repeated until the right turning vehicle VA passes the virtual intersection area VACS. Note that it is also possible to eliminate the processing in S1414 and S1415 themselves, as S1114 and S1115 described above.

[0220] In the flowchart illustrated in Fig. 19, the controller 101b reads various kinds of control information used for the information presentation processing, such as the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA (S1511), and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map (S1512). In S1513, the controller 101b determines whether the right turning vehicle VA, which is another vehicle, is located outside the virtual predicted collision area VACP, reads the vehicle speed VSPa of the right turning vehicle VA (S1514) in a case where the controller 101b determines that the right turning vehicle VA is located outside the virtual predicted collision area VACP, and determines whether the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the predetermined vehicle speed VSP1 (S1515). The controller 101b performs the processing in and after S1516 in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, or ends the information presentation processing in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1. The controller 101b may determine whether the operation of the right turn signal is being continued in addition to the processing in S1513, and execute the processing in and after S1514 in a case where the operation of the right turn signal is being continued. Then, the controller 101b calculates the virtual intersection arrival distance Db' of the straight traveling vehicle VB, which is the host vehicle (S1516), reads the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) (S1517), and calculates the information presentation distance Dth3 (S1518). The processing proceeds to S1520 to issue a notification for information presentation in a case where the intersection arrival distance Db is equal to or less than the information presentation distance Dth3 (S1519), or the information presentation processing is ended in a case where the virtual intersection arrival distance Db' is greater than the information presentation distance Dth3.

[0221] In the flowchart illustrated in Fig. 20, the controller 101b reads various kinds of control information used for the alarm processing such as the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA (S1611), and specifies the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map are (S1612). The controller 101b determines whether the right turning vehicle VA, which is another vehicle, is located inside the virtual predicted collision area VACP, in S1613, reads the vehicle speed VSPa of the right turning vehicle VA (S1614) in a case where the right turning vehicle VA is determined not to be located inside the virtual predicted collision area VACP, and determines whether the vehicle speed VSPa of the right turning vehicle VA is greater than the predetermined vehicle speed VSP1 (S1615). The fact that the operation of the right turn signal, which is used to detect the right turn intention of the right turning vehicle VA, is being continued may be included as a condition of performing the processing as a premise of performing the processing in S1613. The controller 101b performs the processing in and after S1616 in a case where the vehicle speed VSPa is greater than the predetermined vehicle speed VSP1, or ends the alarm processing in a case where the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1. Then, the controller 101b calculates the virtual intersection arrival distance Db' of the straight traveling vehicle VB, which is a host vehicle (S1616), reads the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) (S1617), and calculates the alarm distance Dth4 (S1618). The processing proceeds to S1620 to issue a notification for the alarm in a case where the virtual intersection arrival distance Db' is equal to or less than the alarm distance Dth4, or the alarm processing is ended in a case where the virtual intersection arrival distance Db' is greater than the alarm distance Dth4.(Description of Actions and Effects)

[0222] The vehicle notification system 1 according to the present embodiment has the aforementioned configuration. Effects obtained by the present embodiment will be described below.

[0223] First, in a traffic situation where the right turning vehicle VA turning right at the intersection CS and the straight traveling vehicle VB traveling in the straight direction toward the intersection CS in the opposite lane L22 are present, the current position Pa of the right turning vehicle VA on the road map and the current position Pb of the straight traveling vehicle VB on the road map are specified. Then, notifications in different modes are issued under the condition that the notification issuance condition related to the distance Db of the straight traveling vehicle VB is established at each of a timing at which presence of the right turning vehicle VA at the first predetermined position P1 or a position closer to the intersection center CTR than the first predetermined position P1 is detected after the right turn intention of the right turning vehicle VA is detected and a timing at which the right turning vehicle VA is traveling toward the predicted collision point CPP at a position closer to the predicted collision point CPP than the first predetermined position P1 or enters to a position closer to the predicted collision point CPP than the second predetermined position P2. It is thus possible to realize a notification in an appropriate mode in accordance with the relative relationship between the right turning vehicle VA and the straight traveling vehicle VB.

[0224] Specifically, the notification in the first predetermined mode is issued to the traffic participants under the condition that the straight traveling vehicle VB is located at the first predetermined distance, that is, the information presentation distance Dth1 from the intersection CS or is present at a position closer to the intersection CS than the information presentation distance Dth1 at a timing at which the right turning vehicle VA is located at a position with a relatively long distance left to the predicted collision point CPP after the detection of the right turn intention. In the present embodiment, both the right turning vehicle VA and the straight traveling vehicle VB are considered the traffic participants as targets of notification issuance.

[0225] On the other hand, a notification in the second predetermined mode, which is different from the first predetermined mode, is issued to the traffic participants under the condition that the straight traveling vehicle VB is located at a position closer to the intersection CS, that is, at the second predetermined distance (alarm distance Dth2) from the intersection CS or is present at a position closer to the intersection CS than the alarm distance Dth2 in a case where the right turning vehicle VA is still continuing to travel even after passing the position of the first predetermined position P1 or has approached the position closer to the predicted collision point CPP.

[0226] In this manner, the notification issuance for the purpose of promoting recognition of the presence of the counterpart vehicle (the straight traveling vehicle VB for the right turning vehicle VA, for example), that is, the notification issuance for the information presentation is executed as the first predetermined mode, and the notification issuance for the purpose of promoting recognition of higher urgency, that is, the notification issuance for the alarm is executed as the second predetermined mode, in accordance with the relative positional relationship between the right turning vehicle VA and the straight traveling vehicle VB, for example.

[0227] Second, it is possible to promote the drivers to quickly and easily understand notification issuance and content thereof by issuing the notification using display and / or sound and differentiating the display or the sound between the first predetermined mode and the second predetermined mode.

[0228] Third, it is possible to easily determine the timing at which the notification issuance in the first predetermined mode and the notification issuance in the second predetermined mode are to be executed and to execute the notification issuance by the intersection area ACS and the predicted collision area ACP being set.

[0229] Fourth, it is possible to execute the notification issuance in each of the first and second predetermined modes at an appropriate timing that reflects the distance required to decelerate and brake the straight traveling vehicle VB by calculating the first and second predetermined distances (the information presentation distance Dth1 and the alarm distance Dth2) on the basis of the vehicle speed VSPb of the straight traveling vehicle VB.

[0230] Fifth, it is possible to execute the notification issuance in each of the first and second predetermined modes at a timing according to the behavior of the vehicle at the time of causing the brake to work by setting the deceleration degree DEC1 for calculating the information presentation distance and the deceleration degree DEC2 for calculating the alarm distance, which is higher than the deceleration degree DEC1, and calculating the first and second predetermined distances on the basis of the deceleration degrees DEC1 and DEC2 along with the vehicle speed VSPb of the straight traveling vehicle VB.

[0231] Sixth, it is possible to perform notification issuance in the first predetermined mode at a timing on the assumption of slower braking and to perform the notification issuance in the second predetermined mode at a timing on the assumption of sudden breaking by setting the deceleration degree DEC2 for calculating the alarm distance to be higher than the deceleration degree DEC1 for calculating the information presentation distance.

[0232] Seventh, it is possible to more appropriately calculate the timing at which the notification issuance for each of the information presentation and the alarm is actually performed such that a trend (a degree of slowness or suddenness, for example) of the braking operation that the driver actually performs is reflected, and it is possible to execute the notification issuance in each mode at a more appropriate timing, by learning the actual deceleration degree of the straight traveling vehicle VB for the notification issuance in the second predetermined mode and correcting the deceleration degrees DEC1 and DEC2 used to calculate each of the information presentation distance Dth1 and the alarm distance Dth2 on the basis of the thus obtained learning value.

[0233] Here, it is possible to avoid a situation in which the notification issuance is unnecessarily executed in a case where the display of entrance to the right turn lane L11 or the like is not based on the original right turn intention and the entrance is only temporarily made, by detecting the right turn intention in a case where the right turn intention displayed by the entrance to the right turn lane L11 or the operation of the right turn signal or the like continues for a predetermined period of time or more. In a case where another vehicle is stopping at a roadside of a road extending after the intersection CS or an obstacle installed on the road such as a sign is present, for example, lanes may be changed before or after the entrance to the intersection CS for the purpose of avoiding collision against the obstacle. The right turn intention is not detected in such a case, the right turning vehicle VA ends the control on the basis of negative determination in S113 illustrated in Fig. 4, and the straight traveling vehicle VB ends the control on the basis of negative determination in S413 illustrated in Fig. 7, to thereby avoid the unnecessary notification issuance.

[0234] In contrast, in a case of right turn based on the original right turn intention, the right turning vehicle VA has been decelerated before entering the intersection CS, and some period of time is secured before the entrance to the intersection CS after the display of the right turn intention. Therefore, there are no substantial adverse effects in the detection of the right turn intention even if the continued display of the right turn intention is used as the condition for detecting the right turn intention, and it is possible to appropriately detect that the right turning vehicle VA has the right turn intention.

[0235] In addition, it is possible to issue a notification with higher urgency with a higher priority and to promote the driver to accurately recognize the situation by prioritizing the notification issuance for the alarm than the notification issuance for the information presentation in a case where the notification issuance condition for the information presentation and the notification issuance condition for the alarm are established at the same time.

[0236] The traffic participants as targets of the notification issuance are not limited to the right turning vehicle VA and the straight traveling vehicle VB and may be any other vehicles that are approaching the intersection CS. It is possible to exemplify, as such vehicles, a vehicle traveling toward the intersection CS (hereinafter, referred to as a "crossing vehicle") in a lane other than the right turn lane L11 and lanes extending in parallel to the right turn lane L11 (for example, the straight lane L12), specifically, a lane intersecting the right turn lane L11 from among lanes leading to the intersection CS to which the right turning vehicle VA is directed. Here, a vehicle other than the right turning vehicle VA that is approaching an intersection CS and may enter the intersection CS is referred to as an "intersection-entering vehicle". The intersection-entering vehicles include the straight traveling vehicle VB and the crossing vehicle.

[0237] In the load R illustrated in Fig. 11, a traffic situation in which vehicles traveling toward the intersection CS include a crossing vehicle (not shown) in addition to the right turning vehicle VA and the straight traveling vehicle is assumed. In this situation, when a traffic signal to regulate passing of the crossing vehicle that enters the intersection CS is not installed, there is a concern that the timing at which the crossing vehicle enters the intersection CS and the timings at which the right turning vehicle VA and the straight traveling vehicle VB enter the intersection CS may become the same and these vehicles may be brought into contact with or collide against each other at the intersection CS.

[0238] In such a situation, the notification system 1 monitors the relative positional relationship between the right turning vehicle VA and the crossing vehicle in addition to or instead of the control related to the notification between the right turning vehicle VA and the straight traveling vehicle VB after detecting the right turn intention of the right turning vehicle VA. Then, similarly to the above description, the notification issuance in accordance with urgency of the situation related to contact or collision between the right turning vehicle VA and the crossing vehicle is executed at an appropriate timing before the right turning vehicle VA passes the intersection CS after approaching the intersection CS. For example, the right turning vehicle VA and the crossing vehicle perform information presentation processing and alarm processing similar to those performed between the right turning vehicle VA and the straight traveling vehicle VB.

[0239] Furthermore, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that regards the point at which the right turning path TRa' where the right turning vehicle VA travels when the right turning vehicle VA turns right at the virtual intersection VCS and enters the predetermined area PA located on the roadside along the opposite lane L22 of the road R and the center line CL of the road R intersect as the virtual intersection center VCTR, regards the point at which the right turning path TRa' and the straight traveling path TRb' of the straight traveling vehicle VB intersect as the virtual predicted collision point VCPP, and sets the virtual intersection area VACS including the virtual intersection center VCTR and the virtual predicted collision area VACP including the virtual predicted collision point VCPP in an associated manner on the road map in a case where the right turning vehicle VA and the straight traveling vehicle VB are present and the right turn intention of the right turning vehicle VA is detected. Therefore, the notification system 1 can perform the notification issuance in the third predetermined mode with an intention to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA under the condition that the third predetermined notification issuance condition defined in advance in regard to the position of the straight traveling vehicle VB is met at the third notification issuance timing set in accordance with the relative positional relationship between the virtual intersection area VACS and the right turning vehicle VA. In addition, the notification system 1 can perform the notification issuance in the fourth predetermined mode with an intention to provide an alarm to promote recognition of high urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA under the condition that the fourth notification issuance condition defined in advance in regard to the position of the straight traveling vehicle VB is met at the fourth notification issuance timing set in accordance with the positional relationship among the virtual intersection area VACS, the virtual predicted collision area VACP, and the right turning vehicle VA. Therefore, the notification system 1 can perform the notification issuance in an appropriate mode at an appropriate timing in accordance with a degree of urgency of the situation where there is a concern that the right turning vehicle VA and the straight traveling vehicle VB may collide against each other at a location other than the intersection CS of the road R.

[0240] Furthermore, the notification system 1 according to the present embodiment includes the first notification issuing unit B118a that does not perform the notification issuance in the third predetermined mode and the second notification issuing unit B119a that does not perform the notification issuance in the fourth predetermined mode in a case where the right turning vehicle VA enters the intersection area ACS that overlaps the path TRa where the right turning vehicle VA travels when the right turning vehicle VA turns right at and passes the intersection CS leading to the traveling lane L11. Therefore, the notification system 1 can distinguish the case of turning right at the intersection CS and the case of turning right at a location other than the intersection CS, that is, turning right at the virtual intersection VCS, and perform the notification issuance in an appropriate predetermined mode (the notification issuance in the first predetermined mode and the notification issuance in the second predetermined mode) when the right turning vehicle VA passes through the intersection CS in a case where the right turning vehicle VA actually passes the intersection CS even after the setting of the virtual intersection area VACS and the virtual predicted collision area VACP.

[0241] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that does not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance Dab between the right turning vehicle VA and the straight traveling vehicle VB exceeds the predetermined separation distance Dth5. Therefore, the notification system 1 can reduce the calculation load by not setting the unnecessary virtual intersection area VACS and virtual predicted collision area VACP in a case where the distance between the right turning vehicle VA and the straight traveling vehicle VB is sufficiently long and the risk of collision between the right turning vehicle VA and the straight traveling vehicle VB is low. On the other hand, the notification system 1 can perform the notification in a predetermined mode with an appropriate positional relationship between the right turning vehicle VA and the straight traveling vehicle VB by setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the distance Dab is equal to or less than the predetermined separation distance Dth5.

[0242] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that does not set the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the vehicle speed VSPa of the right turning vehicle VA exceeds the second predetermined vehicle speed VSP2 that is higher than the first predetermined vehicle speed VSP1. Therefore, the notification system 1 can reduce the calculation load by not setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where it is determined that the right turning vehicle VA will not turn right. On the other hand, the notification system 1 can perform the notification in a predetermined mode with an appropriate positional relationship between the right turning vehicle VA and the straight traveling vehicle VB by setting the virtual intersection area VACS and the virtual predicted collision area VACP in a case where the vehicle speed VSPa is equal to or less than the second predetermined vehicle speed VSP2.

[0243] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that sets the virtual intersection area VACS with the outer edge that includes the four vertices of the virtual intersection VCS. Therefore, the notification system 1 can more appropriately use the virtual intersection area VACS as a determination criterion for recognizing the relative positional relationship between the right turning vehicle VA and the virtual intersection VCS.

[0244] Furthermore, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that sets the virtual intersection area VACS such that the right turning vehicle VA is not present inside the virtual intersection area VACS and the outer edge of the virtual intersection area VACS is located just in front of the right turning vehicle VA. Therefore, the notification system 1 can more reliably perform the notification issuance in the third predetermined mode with an intention to present information for relatively low urgency in regard to collision between the straight traveling vehicle VB and the right turning vehicle VA and the notification issuance in the fourth predetermined mode with an intention to provide an alarm to promote recognition of high urgency as compared with a case where the virtual intersection area VACS is set so as to be located far away from the right turning vehicle VA on the front side.

[0245] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that sets the right turning path TRa' in an associated manner on the road map on the basis of at least one of the destination information of the navigation device 115a in which the predetermined area PA is set as a destination, the steering amount of the right turning vehicle VA detected by the steering angle sensor 114a as the steering amount detection section, and the vehicle speed VSPa of the right turning vehicle VA. Therefore, the notification system 1 can accurately set the right turning path TRa' and improve the setting accuracy of the virtual intersection area VACS and the virtual predicted collision area VACP that are set on the basis of the right turning path TRa'. In other words, the notification system 1 can accurately perform the notification issuance in a predetermined mode based on the virtual intersection area VACS and the virtual predicted collision area VACP.

[0246] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that determines the virtual intersection area VACS from among at least one virtual intersection area candidate VACSC, which is a candidate for the virtual intersection area VACS, and determines the virtual predicted collision area VACP from among at least one virtual predicted collision area candidate VACPC, which is a candidate for the virtual predicted collision area VACP, by determining the predetermined area PA from among at least one predetermined area candidate PAC, which is a candidate for the predetermined area PA. Therefore, the notification system 1 can shorten the setting processing time for the virtual intersection area VACS and the virtual predicted collision area VACP after the predetermined setting condition is met and can improve accuracy when the notification in a predetermined mode is performed by setting the virtual intersection area VACS and the virtual predicted collision area VACP with no delay.

[0247] In addition, the notification system 1 according to the present embodiment includes the virtual area setting unit B122a that determines the predetermined area PA from among at least one predetermined area candidate PAC on the basis of at least one of the steering amount of the right turning vehicle VA detected by the steering angle sensor 114a as the steering amount detection and notification section and the vehicle speed VSPa of the right turning vehicle VA. Therefore, the notification system 1 can set the virtual intersection area VACS and the virtual predicted collision area VACP without delay and with high accuracy, allowing for more precise notification in a predetermined mode.

[0248] In the above description, the distance from the outer edge of the predicted collision area ACP, specifically, the intersecting point between the traveling path TRb of the straight traveling vehicle VB and the circle (the circles illustrated by the dashed lines in Figs. 12 and 13) defining the outer edge of the predicted collision area ACP to the straight traveling vehicle VB is employed as the intersection arrival distance Db from the intersection CS to the straight traveling vehicle VB. The intersection arrival distance Db is not limited thereto, and the distance from the predicted collision point CPP to the straight traveling vehicle VB may be employed, or the distance along the center line of the opposite lane L22 from the right turning vehicle VA to the straight traveling vehicle VB may be employed, as the intersection arrival distance Db. In the same manner, the distance from the outer edge of the predicted collision area ACP, specifically, the intersecting point between the traveling path TRb' of the straight traveling vehicle VB and the circle (the circles illustrated by the dashed lines in Figs. 22 and 23) defining the outer edge of the virtual predicted collision area VACP to the straight traveling vehicle VB is employed as the virtual intersection arrival distance Db' from the virtual intersection VCS to the straight traveling vehicle VB. The virtual intersection arrival distance Db' is not limited thereto, and the distance from the virtual predicted collision point VCPP to the straight traveling vehicle VB may be employed, or the distance along the center line of the opposite lane L22 from the right turning vehicle VA to the straight traveling vehicle VB may be employed, as the virtual intersection arrival distance Db'. In addition, at the virtual intersection VCS having a regular square shape, the distance from the side of the virtual intersection VCS closer to the straight traveling vehicle VB to the straight traveling vehicle may be employed, as the virtual intersection arrival distance Db'.

[0249] Furthermore, although the controllers 101a and 101b included in the right turning vehicle VA and the straight traveling vehicle VB, respectively constitute the calculation unit of the notification system 1 and the controllers 101a and 101b constitute one virtual controller, a configuration in which roadside equipment or a remote server is caused to have the road map and a computer program for the notification control and is caused to perform the notification control outside the vehicles may also be adopted. In this case, the right turning vehicle VA and the straight traveling vehicle VB transmit position information of the respective vehicles to the external controller through road-to-vehicle communication and receive command signals which are results of calculation related to control. Then, the notification issuance for the information presentation or the alarm is executed on the basis of the command signals.

[0250] In the above description, a traffic situation where the right turning vehicle VA traveling toward a predetermined section of the left-hand traffic road R to turn right at the predetermined section and the straight traveling vehicle VB traveling in the straight traveling direction toward the predetermined section in the opposite lane L22 that is opposite to the traveling lane L11 where the right turning vehicle VA travels are present is assumed. Also, the notification system 1 that assumes the intersection CS as the predetermined section of the road R and the virtual intersection VCS that is a location other than the intersection and performs notification issuance to avoid collision between the right turning vehicle VA and the straight traveling vehicle VB when the right turning vehicle VA turns right in each case has been described. Here, the notification system 1 that performs the notification issuance at the virtual intersection VCS, which is a location other than the intersection CS, can actually be applied to the intersection CS as well. In other words, the notification system 1 can perform the notification issuance to avoid collision between the right turning vehicle VA and the straight traveling vehicle VB when the right turning vehicle VA turns right without distinguishing the intersection CS and the location other than the intersection CS, by including the intersection CS in the virtual intersection VCS.

[0251] In other words, the notification system 1 according to the preset embodiment is a vehicle notification system that issues notifications for traffic participants including a right turning vehicle VA that is present in a traveling lane L11 leading to a predetermined section on a road R in order to turn right at the predetermined section and a straight traveling vehicle VB that is traveling in a straight direction on a lane L22 opposite to the traveling lane L11 toward the predetermined section.

[0252] The notification system 1 includes: a road map storage unit B113a that stores a road map including the predetermined section and specifies a current position of the right turning vehicle VA on the road map and a current position of the straight traveling vehicle VB on the road map; and a right turn intention detection unit B114a that detects a right turn intention of the right turning vehicle VA.

[0253] The notification system 1 further includes a virtual area setting unit B122a that in a case where a specification result of the road map storage unit B113a shows that the right turning vehicle VA and the straight traveling vehicle VB are present and the right turn intention detection unit B114a detects the right turn intention, regards, as a virtual intersection center VCTR, a point at which a right turning path TRa' that is a path where the right turning vehicle VA travels when the right turning vehicle VA turns right at the predetermined section and a center line CL that sections the traveling lane L11 and the opposite lane L22 or extension of the center line CL intersect, regards, as a virtual predicted collision point VCPP, a point where the right turning path TRa' and a straight traveling path TRb' that is a path where the straight traveling vehicle VB travels intersect, and sets a virtual intersection area VACS including the virtual intersection center VCTR and a virtual predicted collision area VACP including the virtual predicted collision point VCPP in an associated manner in the road map.

[0254] The notification system 1 further includes: a third vehicle behavior detection unit B120a that sets, as a third notification issuance timing, a timing at which presence of the right turning vehicle VA at a predetermined position relative to the virtual intersection area VACS set by the virtual area setting unit B122a is detected on the basis of the current position of the right turning vehicle VA specified by the road map storage unit; and a fourth vehicle behavior detection unit B121a that sets, as a fourth notification issuance timing that is different from the third notification issuance timing, a timing at which traveling of the right turning vehicle VA toward the virtual predicted collision point VCPP inside the virtual intersection area VACS or presence of the right turning vehicle VA inside the virtual predicted collision area VACP is detected after the third vehicle behavior detection unit B120a sets the third notification issuance timing.

[0255] The notification system 1 further includes: a first notification issuing unit B118a that performs notification issuance in a third predetermined mode for the traffic participants under a condition that a third predetermined notification issuance condition defined in advance in regard to a position of the straight traveling vehicle VB is met at the third notification issuance timing set by the third vehicle behavior detection unit B120a; and a second notification issuing unit B119a that performs notification issuance in a fourth predetermined mode for the traffic participants under a condition that a fourth predetermined notification issuance condition defined in advance in regard to the position of the straight traveling vehicle VB is met at the fourth notification issuance timing set by the fourth vehicle behavior detection unit B121a.

[0256] While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions, and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.REFERENCE SIGNS LIST

[0257] 1Vehicle notification system 101a, 101bController 111a, 111bPosition sensor 112a, 112bVehicle speed sensor 113a, 113bRight turn signal switch 114a, 114bSteering angle sensor 115a, 115bnavigation device 121a, 121bTransmitter 122a, 122bReceiver 131a, 131bHMI device

Examples

Embodiment Construction

[0014]Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the same reference signs are given to identical or equivalent components in each figure.

(Overall Configuration of Vehicle Notification System)

[0015]Fig. 1 is a schematic diagram illustrating a configuration of a vehicle notification system (hereinafter, simply referred to as a "notification system" in some cases) 1 according to an embodiment of the present invention.

[0016] In the present embodiment, a traffic situation where a vehicle (hereinafter, referred to as a "right turning vehicle") VA traveling toward a predetermined section (predetermined location) on a left-hand traffic road in order to turn right at the predetermined section and another vehicle (hereinafter, referred to as a "straight traveling vehicle") VB traveling in a straight direction toward the predetermined section in a lane (hereinafter, referred to as an "opposite lane" in some cases) opposite to a...

Claims

1. A vehicle notification system (1) that issues notifications for traffic participants including a first vehicle (VA) that is present in a traveling lane (L11) leading to a predetermined section on a road (R) in order to turn right or left at the predetermined section and a second vehicle (VB) that is traveling in a straight direction on a lane (L22) opposite to the traveling lane (L11) toward the predetermined section, the vehicle notification system (1) comprising: a road map storage unit (B113a, B113b) that stores a road map including the predetermined section and specifies a current position of the first vehicle (VA) on the road map and a current position of the second vehicle (VB) on the road map; a direction-change-intention detection unit (B114a, B114b) that detects a direction change intention of the first vehicle (VA) turning right or left at the predetermined section; a virtual area setting unit (B122a, B122b) that in a case where a specification result of the road map storage unit (B113a, B113b) shows that the first vehicle (VA) and the second vehicle (VB) are present and the direction-change-intention detection unit (B114a, B114b) detects the direction change intention, regards, as a virtual intersection center (VCTR), a point at which a turning path (TRa') that is a path where the first vehicle (VA) travels when the first vehicle (VA) turns right or left at the predetermined section and enters a predetermined area (PA) located on a roadside along the opposite lane (L22) of the road (R) and a center line (CL) that sections the traveling lane (L11) and the opposite lane (L22) intersect, regards, as a virtual predicted collision point (VCPP), a point where the turning path (TRa') and a straight traveling path (TRb') that is a path where the second vehicle (VB) travels intersect, and sets a virtual intersection area (VACS) including the virtual intersection center (VCTR) and a virtual predicted collision area (VACP) including the virtual predicted collision point (VCPP) in an associated manner in the road map; a third vehicle behavior detection unit (B120a, B120b) that sets, as a third notification issuance timing, a timing at which presence of the first vehicle (VA) at a predetermined position relative to the virtual intersection area (VACS) set by the virtual area setting unit (B122a, B122b) is detected on the basis of the current position of the first vehicle (VA) specified by the road map storage unit (B113a, B113b); a fourth vehicle behavior detection unit (B121a, B121b) that sets, as a fourth notification issuance timing that is different from the third notification issuance timing, a timing at which traveling of the first vehicle (VA) toward the virtual predicted collision point (VCPP) inside the virtual intersection area (VACS) or presence of the first vehicle (VA) inside the virtual predicted collision area (VACP) is detected after the third vehicle behavior detection unit (B120a, B120b) sets the third notification issuance timing; a first notification issuing unit (B118a, B118b) that performs notification issuance in a third predetermined mode for the traffic participants under a condition that a third predetermined notification issuance condition defined in advance in regard to a position of the second vehicle (VB) is met at the third notification issuance timing set by the third vehicle behavior detection unit (B120a, B120b); and a second notification issuing unit (B119a, B119b) that performs notification issuance in a fourth predetermined mode for the traffic participants under a condition that a fourth predetermined notification issuance condition defined in advance in regard to the position of the second vehicle (VB) is met at the fourth notification issuance timing set by the fourth vehicle behavior detection unit (B121a, B121b).

2. The vehicle notification system (1) according to claim 1, wherein in a case where the first vehicle (VA) is present in the traveling lane (L11) leading to an intersection (CS) on the road (R) in order to turn right or left at the intersection (CS), and the first vehicle (VA) has entered an intersection area (ACS) that overlaps a path where the first vehicle (VA) travels when the first vehicle (VA) passes the intersection (CS) and that is set in advance in association with the road map, the first notification issuing unit (B118a, B118b) does not perform the notification issuance in the third predetermined mode, and the second notification issuing unit (B119a, B119b) does not perform the notification issuance in the fourth predetermined mode.

3. The vehicle notification system (1) according to claim 1 or 2, wherein in a case where a distance between the first vehicle (VA) and the second vehicle (VB) exceeds a predetermined separation distance (Dth5), the virtual area setting unit (B122a, B122b) does not set the virtual intersection area (VACS) and the virtual predicted collision area (VACP).

4. The vehicle notification system (1) according to any one of claims 1 to 3, wherein in a case where a vehicle speed of the first vehicle (VA) exceeds a predetermined vehicle speed, the virtual area setting unit (B122a, B122b) does not set the virtual intersection area (VACS) and the virtual predicted collision area (VACP).

5. The vehicle notification system (1) according to any one of claims 1 to 4, wherein the predetermined section is a square section having a side corresponding to a road width of the road (R), and the virtual intersection area (VACS) has an outer edge including four vertices of the predetermined section.

6. The vehicle notification system (1) according to any one of claims 1 to 5, wherein the virtual area setting unit (B122a, B122b) sets the virtual intersection area (VACS) such that the first vehicle (VA) is not present inside the virtual intersection area (VACS) and an outer edge of the virtual intersection area (VACS) is located just in front of the first vehicle (VA).

7. The vehicle notification system (1) according to any one of claims 1 to 6, wherein the virtual area setting unit (B122a, B122b) sets the turning path (TRa') based on destination information of a navigation device in which the predetermined area (PA) is set as a destination or at least one of a steering amount of the first vehicle (VA) detected by a steering amount detection and notification unit and a vehicle speed of the first vehicle (VA).

8. The vehicle notification system (1) according to any one of claims 1 to 6, wherein the virtual area setting unit (B122a, B122b) sets at least one predetermined area candidate (PAC) that is a candidate for the predetermined area (PA), a virtual intersection area candidate (VACSC) that is a candidate for the virtual intersection area (VACS) corresponding to the at least one predetermined area candidate (PAC), respectively, and a virtual predicted collision area candidate (VACPC) that is a candidate for the virtual predicted collision area (VACP) corresponding to the at least one predetermined area candidate (PAC), respectively, in an associated manner on the road map, and determines the virtual intersection area (VACS) from among the at least one virtual intersection area candidate (VACSC) and determines the virtual predicted collision area (VACP) from among the at least one virtual predicted collision area candidate (VACPC) by determining the predetermined area (PA) from among the at least one predetermined area candidate (PAC).

9. The vehicle notification system (1) according to claim 8, wherein the virtual area setting unit (B122a, B122b) determines the predetermined area (PA) from among the at least one predetermined area candidate (PAC) based on at least one of a steering amount of the first vehicle (VA) detected by a steering amount detection and notification unit and a vehicle speed of the first vehicle (VA).

10. A vehicle notification system (1) that performs notification issuance for traffic participants including a first vehicle (VA) and a second vehicle (VB) traveling in a lane (L22) opposite to a lane (L11) where the first vehicle (VA) is traveling in a traffic situation where the first vehicle (VA) and the second vehicle (VB) are present, the vehicle notification system (1) comprising: a road map storage unit (B113a, B113b) that stores a road map; a first vehicle position specification unit (B111a, B112b) that specifies a current position of the first vehicle (VA) on the road map; a second vehicle position specification unit (B111b, B112a) that specifies a current position of the second vehicle (VB) on the road map; a direction-change-intention detection unit (B114a, B114b) that detects a direction change intention of the first vehicle (VA) turning right or left; a virtual area setting unit (B122a, B122b) that sets a virtual area (VACS, VACP) that overlaps a path where the first vehicle (VA) travels when the first vehicle (VA) turns right or left on the road map corresponding to a section between the first vehicle (VA) and the second vehicle (VB) in a case where the direction-change-intention detection unit (B114a, B114b) detects the direction change intention; a notification issuance timing setting unit (B116a, B116b, B117a, B117b, B120a, B120b, B121a, B121b) that sets a notification issuance timing in accordance with a position of the first vehicle (VA) relative to the virtual area (VACS, VACP) set by the virtual area setting unit (B122a, B122b); and a notification issuing unit (B118a, B118b, B119a, B119b) that performs notification issuance in a predetermined mode for the traffic participants under a condition that a predetermined notification issuance condition defined in regard to a position of the second vehicle (VB) is met at the notification issuance timing set by the notification issuance timing setting unit (B116a, B116b, B117a, B117b, B120a, B120b, B121a, B121b).

Images