Vehicle notification system

Abstract

A vehicle notification system specifies a current position of a right turning vehicle on a road map and a current position of a straight traveling vehicle on the road map. In a case where the right turning vehicle enters an intersection area after detection of a right turn intention, a notification in a first predetermined mode is issued for traffic participants under a condition that the straight traveling vehicle is located at a first predetermined distance from the intersection or is present at a position closer to the intersection than the first predetermined distance. On the other hand, in a case where the right turning vehicle is traveling toward a predicted collision point outside a predicted collision area or has entered the predicted collision area after the entrance to the intersection area, a notification in a second predetermined mode is issued to the traffic participants under a condition that the straight traveling vehicle is located at a second predetermined distance from the intersection or is present at a position closer to the intersection than the second predetermined distance.

Description

BACKGROUND OF THE INVENTIONField of the Invention

[0001] The present invention relates 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.Citation ListPatent Document

[0004] Patent Document 1: Japanese Patent Laid-Open No. 2009-265832

[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.SUMMARY OF THE INVENTION

[0008] Thus, an object of the present invention is to provide a vehicle notification system that contributes to a further improvement in traffic safety.

[0009] To solve the above-mentioned problem, a vehicle notification system according to one aspect of the present invention is configured to issue a notification to traffic participants including a first vehicle that is present in a traveling lane leading to an intersection and turns right or left at the intersection and a second vehicle that travels in a straight direction toward the intersection in a lane opposite to the traveling lane.

[0010] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, 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 while turning right or left at the intersection, a first vehicle behavior detection unit that detects, on a basis of the current position of the first vehicle specified by the first vehicle position specification unit, that the first vehicle is present at a first predetermined position in the traveling lane or a position closer to an intersection center than the first predetermined position after the direction-change-intention detection unit detects the direction change intention, the intersection center being a center position of the intersection, a second vehicle behavior detection unit that regards, as a predicted collision point, a point at which a path along which the first vehicle travels when passing the intersection and a path along which the second vehicle travels when passing the intersection intersect and detects, on the basis of the current position of the first vehicle, that the first vehicle is traveling at a position closer to the predicted collision point than the first predetermined position toward the predicted collision point or that the first vehicle is present at a position closer to the predicted collision point than a second predetermined position between the first predetermined position and the predicted collision point, a first notification issuing unit that issues a notification in a first predetermined mode to the traffic participants under a condition that the second vehicle is located at a first predetermined distance from the intersection or is present at a location closer to the intersection than the first predetermined distance in a case where the first vehicle behavior detection unit detects that the first vehicle is present at the first predetermined position or the position that is closer to the intersection center than the first predetermined position, and a second notification issuing unit that issues a notification in a second predetermined mode that is different from the first predetermined mode to the traffic participants under a condition that the second vehicle is located at a second predetermined distance from the intersection or is present at a position closer to the intersection than the second predetermined distance in a case where the second vehicle behavior detection unit detects that the first vehicle is traveling at a position closer to the predicted collision point than the first predetermined position or that the first vehicle is present at a position closer to the predicted collision point than the second predetermined position, the second predetermined distance being shorter than the first predetermined distance.

[0011] The first notification issuing unit and the second notification issuing unit may be configured to issue the respective notifications using mutually different displays or sounds.

[0012] An intersection area that overlaps the path along which the first vehicle travels when passing the intersection and that includes the first predetermined position on an outer edge and a predicted collision area that includes the predicted collision point therein and includes the second predetermined position on an outer edge may be set in an associated manner in the road map.

[0013] In this case, the first vehicle behavior detection unit may be configured to detect that the first vehicle is present inside the intersection area after the detection of the direction change intention, and the second vehicle behavior detection unit may be configured to detect that the first vehicle is traveling toward the predicted collision point inside the intersection area or is present inside the predicted collision area.

[0014] The first vehicle behavior detection unit may be detect that the first vehicle is stopping or is in a low-speed traveling state at a predetermined vehicle speed or less inside the intersection area after the detection of the direction change intention.

[0015] In this case, the first notification issuing unit may be configured to issue the notification in the first predetermined mode under the condition that the second vehicle is located at the first predetermined distance from the intersection or is present at the position closer to the intersection than the first predetermined distance in the case where the first vehicle is stopping or is in the low-speed traveling state inside the intersection area.

[0016] The vehicle notification system may further include a vehicle speed detection unit that detects a vehicle speed of the second vehicle.

[0017] In this case, the first notification issuing unit may be configured to calculate the first predetermined distance on a basis of the vehicle speed of the second vehicle detected by the vehicle speed detection unit, and the second notification issuing unit may be configured to calculate the second predetermined distance on the basis of the vehicle speed of the second vehicle detected by the vehicle speed detection unit.

[0018] The first notification issuing unit may be configured to calculate the first predetermined distance on a basis of the vehicle speed of the second vehicle and the first predetermined deceleration degree set in advance.

[0019] The second notification issuing unit may be configured to calculate the second predetermined distance on a basis of the vehicle speed of the second vehicle and the second predetermined deceleration degree set in advance as a deceleration degree that is higher than the first predetermined deceleration degree.

[0020] The vehicle notification system may further include a deceleration degree learning unit that learns an actual deceleration degree when the second vehicle decelerates in response to the notification issuance in the second predetermined mode and calculates a learning value that indicates the actual deceleration degree.

[0021] In this case, the vehicle notification system may further include a deceleration degree correcting unit that corrects at least one of the first predetermined deceleration degree and the second predetermined deceleration degree on a basis of the learning value calculated by the deceleration degree learning unit.

[0022] The direction-change-intention detection unit may be configured to detect the direction change intention in a case where the direction change intention of the first vehicle has continued for a predetermined period of time or more.

[0023] The notification issuance in the second predetermined mode by the second notification issuing unit may be prioritized over the notification issuance in the first predetermined mode by the first notification issuing unit.

[0024] In another aspect of the present invention, a vehicle notification system is configured to issue a notification related to other traffic participants including vehicles other than a host vehicle that turns right or left at an intersection.

[0025] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, a direction-change-intention detection unit that detects a direction change intention of the host vehicle while turning right or left at the intersection, a host vehicle position specification unit that specifies a current position of the host vehicle on the road map, an other vehicle information acquisition unit that acquires vehicle information including position information about another vehicle through communication with another vehicle, when there is another vehicle traveling in a straight direction toward the intersection in a lane opposite to the traveling lane where the host vehicle is present, an other vehicle position specification unit that specifies a current position of another vehicle on the road map on a basis of the vehicle information of another vehicle acquired by the other vehicle information acquisition unit, a first vehicle behavior detection unit that detects, on a basis of the current position of the host vehicle specified by the host vehicle position specification unit, that the host vehicle is present at a first predetermined position in the traveling lane or a position closer to an intersection center that is a center position of the intersection than the first predetermined position after the direction-change-intention detection unit detects the direction change intention, a second vehicle behavior detection unit that regards, as a predicted collision point, a point at which a path along which the host vehicle travels when passing the intersection and a path along which another vehicle travels when passing the intersection intersect and detects that the host vehicle is traveling at a position closer to the predicted collision point than the first predetermined position toward the predicted collision point or that the host vehicle is present at a position closer to the predicted collision point than a second predetermined position between the first predetermined position and the predicted collision point, a first notification issuing unit that issues a notification in a first predetermined mode under a condition that another vehicle is located at a first predetermined distance from the intersection or is present at a location closer to the intersection than the first predetermined distance in a case where the first vehicle behavior detection unit detects that the host vehicle is present at the first predetermined position or the position that is closer to the intersection center than the first predetermined position, and a second notification issuing unit that issues a notification in a second predetermined mode that is different from the first predetermined mode under a condition that another vehicle is located at a second predetermined distance that is shorter than the first predetermined distance from the intersection or is present at a position closer to the intersection than the second predetermined distance in a case where the second vehicle behavior detection unit detects that the host vehicle is traveling at a position closer to the predicted collision point than the first predetermined position or that the host vehicle is present at a position closer to the predicted collision point than the second predetermined position.

[0026] The vehicle notification system may further include a specific vehicle information transmitting unit that transmits specific vehicle information to another vehicle. The specific vehicle information may indicate implementation of at least one of the notifications by the first notification issuing unit and the second notification issuing unit.

[0027] In a further aspect of the present invention, a vehicle notification system is configured to issue a notification related to other traffic participants including vehicles other than a host vehicle that travels in a straight direction toward an intersection.

[0028] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, a host vehicle position specification unit that specifies a current position of the host vehicle on the road map, an other vehicle information acquisition unit that acquires vehicle information including position information about another vehicle through communication with another vehicle, when there is another vehicle in a lane opposite to the lane where the host vehicle travels, a direction-change-intention detection unit that detects a direction change intention of another vehicle while turning right or left at the intersection on a basis of the vehicle information of another vehicle acquired by the other vehicle information acquisition unit, an other vehicle position specification unit that specifies a current position of another vehicle on the road map based on the vehicle information of another vehicle, a first vehicle behavior detection unit that detects, on a basis of the current position of another vehicle specified by the other vehicle position specification unit, that another vehicle is present at a first predetermined position in the opposite lane or a position closer to an intersection center that is a center position of the intersection than the first predetermined position after the direction-change-intention detection unit detects the direction change intention, a second vehicle behavior detection unit that regards, as a predicted collision point, a point at which a path along which the host vehicle travels when passing the intersection and a path along which another vehicle travels when passing the intersection intersect and detects that another vehicle is traveling at a position closer to the predicted collision point than the first predetermined position toward the predicted collision point or that another vehicle is present at a position closer to the predicted collision point than a second predetermined position between the first predetermined position and the predicted collision point, a first notification issuing unit that issues a notification in a first predetermined mode under a condition that the host vehicle is located at a first predetermined distance from the intersection or is present at a location closer to the intersection than the first predetermined distance in a case where the first vehicle behavior detection unit detects that another vehicle is present at the first predetermined position or the position that is closer to the intersection center than the first predetermined position, and a second notification issuing unit that issues a notification in a second predetermined mode that is different from the first predetermined mode under a condition that the host vehicle is located at a second predetermined distance that is shorter than the first predetermined distance from the intersection or is present at a position closer to the intersection than the second predetermined distance in a case where the second vehicle behavior detection unit detects that another vehicle is traveling at a position closer to the predicted collision point than the first predetermined position or that another vehicle is present at a position closer to the predicted collision point than the second predetermined position.

[0029] The vehicle notification system may further include a specific vehicle information transmitting unit that transmits specific vehicle information to another vehicle. The specific vehicle information may indicate implementation of at least one of the notifications by the first notification issuing unit and the second notification issuing unit.

[0030] In a still further aspect of the present invention, a vehicle notification system is configured to issue a notification to traffic participants including a first vehicle and a second vehicle, the first vehicle being present in a traveling lane leading to an intersection and turning right or left at the intersection, and the second vehicle traveling toward the intersection in a lane leading to the intersection other than the traveling lane.

[0031] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, 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 while turning right or left at the intersection, a first issuance timing setting unit that sets a first issuance timing according to a relative position of the first vehicle with respect to an intersection area based on the current position of the first vehicle specified by the first vehicle position specification unit, the intersection area overlapping the path along which the first vehicle travels when passing the intersection and being set in association with the road map, a second issuance timing setting unit that sets a second issuance timing according to a behavior of the first vehicle within the intersection area, after the first issuance timing has been set by the first issuance timing setting unit, and a notification issuing unit that issues a notification in a predetermined mode to the traffic participants under a condition that issuance conditions defined with respect to a position of the second vehicle are satisfied at each of the first issuance timing set by the first issuance timing setting unit and the second issuance timing set by the second issuance timing setting unit.

[0032] In a still further aspect of the present invention, a vehicle notification system is configured to issue a notification to traffic participants including a first vehicle and a second vehicle, the first vehicle being present in a traveling lane leading to an intersection and turning right or left at the intersection, and the second vehicle traveling toward the intersection in a lane leading to the intersection other than the traveling lane.

[0033] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, 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 while turning right or left at the intersection, a first issuance timing setting unit that sets a first issuance timing when the first vehicle is present in an intersection area, the intersection area overlapping the path along which the first vehicle travels when passing the intersection and being set in association with the road map, a second issuance timing setting unit that sets a second issuance timing when the first vehicle is in a predicted collision area, the predicted collision area being different from the intersection area and including a predicted collision point at which a path along which the first vehicle travels when passing the intersection and a path along which the second vehicle travels when passing the intersection intersect, and a notification issuing unit that issues a notification in a predetermined mode to the traffic participants under a condition that issuance conditions defined with respect to a position of the second vehicle are satisfied at each of the first issuance timing set by the first issuance timing setting unit and the second issuance timing set by the second issuance timing setting unit.

[0034] The second vehicle may be a straight traveling vehicle traveling towards the intersection in a lane opposite to the traveling lane.

[0035] The second vehicle may be a crossing vehicle traveling towards the intersection in a lane intersecting the traveling lane.

[0036] According to one aspect of the present invention, it is possible to realize an appropriate notification in an appropriate mode in accordance with a relative relationship between a first vehicle that turns right or left at an intersection and a second vehicle that travels in a straight direction toward the intersection in an opposite lane in a situation where the first vehicle and the second vehicle are present, and to promote a driver to accurately recognize urgency of the circumstances.BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Fig. 1 is a schematic diagram illustrating an overall configuration of a vehicle notification system according to an embodiment of the present embodiment; 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 executed by the right turning vehicle; Fig. 5 is a flowchart illustrating content of the notification control (information presentation processing) executed by the right turning vehicle; Fig. 6 is a flowchart illustrating content of the notification control (alarm processing) executed by the right turning vehicle; Fig. 7 is a flowchart illustrating an overall flow of notification control executed by the straight traveling vehicle; Fig. 8 is a flowchart illustrating content of the notification control (information presentation processing) executed by the straight traveling vehicle; Fig. 9 is a flowchart illustrating content of the notification control (alarm processing) executed by the straight traveling vehicle; 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 schematically illustrating an example of a traffic situation assumed as 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 issuance timing of information presentation; Fig. 13 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an issuance timing of an alarm; Fig. 14 is a schematic diagram illustrating a situation after the straight traveling vehicle passes an intersection; Fig. 15 is a schematic diagram schematically illustrating another example of a traffic situation assumed as a target of a notification; Fig. 16 is a schematic diagram illustrating a relationship among the right turning vehicle, the straight traveling vehicle, and a crossing vehicle at an issuance timing of information presentation; and Fig. 17 is a schematic diagram illustrating a relationship among the right turning vehicle, the straight traveling vehicle, and the crossing vehicle at an issuance timing of an alarm. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] Hereinafter, embodiments of the present invention will be described with reference to the drawings.(Overall Configuration of Vehicle Notification System)

[0039] 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.

[0040] In the present embodiment, a traffic situation where a vehicle (hereinafter, referred to as a "right turning vehicle") VA traveling toward an intersection on a left-hand traffic road and another vehicle (hereinafter, referred to as a "straight traveling vehicle") VB traveling in a straight direction toward the intersection 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 toward an intersection and a straight traveling vehicle traveling toward the intersection in an opposite lane are present is 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 intersection and should not hinder the straight traveling vehicle traveling in the opposite lane from passing the intersection.

[0041] 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.

[0042] 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.

[0043] 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 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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 high-precision satellite positioning 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).

[0048] 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.

[0049] 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.

[0050] Detection signals from the position sensor 111a, the vehicle speed sensor 112a, and the right turn signal switch 113a are output to the controller 101a, while detection signals from the position sensor 111b, the vehicle speed sensor 112b, and the right turn signal switch 113b are output to the controller 101b.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] Fig. 11 is a schematic diagram schematically illustrating an example of a traffic situation assumed as a notification target according to the present embodiment.

[0056] 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.

[0057] In addition to the right turning vehicle VA and the straight traveling vehicle VB, a vehicle (hereinafter, referred to as a "waiting vehicle") VZ 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 VZ 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 VZ 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 VZ seen from the straight traveling vehicle VB.

[0058] 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. 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.(Internal Configuration of Controller)

[0059] 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 Fig. 11 as needed.

[0060] As illustrated in Fig. 2, the controller 101a 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, and a second notification issuing unit B119a. A function of each of these units B111a to B119a 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.

[0061] 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 of the host vehicle 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.

[0062] 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 of another vehicle 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.

[0063] 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. In the road map, identifiers (hereinafter, referred to as "link IDs") corresponding to lanes leading to the intersection CS, such as the right turn lanes L11 and L21 and the straight lanes L12 and L22, are assigned and are stored 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 on the road map.

[0064] 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 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.

[0065] 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.

[0066] 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.

[0067] 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).

[0068] In the present embodiment, an intersection area ACS is set as a determination criterion to recognize the relative positional relationship between the right turning vehicle VA and 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 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 twodotted 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.

[0069] 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.

[0070] 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.

[0071] 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 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.

[0072] 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).

[0073] The first notification issuing unit B118a outputs a command signal to issue a notification in a 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 established at a timing at which 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.

[0074] 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.

[0075] The HMI device 131a that has received the command signal from the first notification issuing unit B118a 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.

[0076] 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.

[0077] 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.

[0078] 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 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.

[0079] The first notification issuing unit B118a and the second notification issuing unit B119a can also provide a notification that the notification in each mode has been issued to the straight traveling vehicle VB via the transmitter 121a in accordance with the output of the command signal to the HMI device 131a and promote a notification to be issued in an appropriate mode in accordance with urgency in regard to collision against the host vehicle (that is, the right turning vehicle VA).

[0080] Fig. 10 is an explanatory diagram illustrating a method of calculating the information presentation distance Dth1 and the alarm distance Dth2.

[0081] 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.

[0082] 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

[0083] 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 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

[0084] 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.

[0085] As illustrated in Fig. 3, the controller 101b 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, and a second notification issuing unit B119b. Differences between an internal configuration of the controller 101b and that of the controller 101a will be mainly described below.

[0086] 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 thereof is based on an output signal from the position sensor 111b included in the straight traveling vehicle VB.

[0087] 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 thereof 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.

[0088] 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 the assigned link ID of each lane leading to 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. Although the road maps stored in the road map storage units B113b and B113a may have different levels of accuracy, both the maps employ an accuracy that is compatible with satellite positioning using GNSS in the present embodiment.

[0089] The right turn intention detection unit B114b is adapted to detect a right turn intention of the right turning vehicle VA, and the detection thereof is based on 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 or 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. 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.

[0090] 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 122a.

[0091] 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.

[0092] The size and the shape of the intersection area ACS may be the same or different between the controller 101a and the controller 101b. 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.

[0093] 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.

[0094] 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.

[0095] 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. 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.

[0096] 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.

[0097] The second notification issuing unit B119b outputs 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. 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.

[0098] 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.

[0099] 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.

[0100] 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 has been issued via the transmitter 121b in accordance with the output of the command signal to the HMI device 131b.(Content of Notification Control in Right Turning Vehicle)

[0101] Figs. 4 to 6 are flowcharts illustrating content of notification control performed by the controller 101a included in the right turning vehicle VA. 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 is detected in a road in front of the host vehicle (that is, the right turning vehicle VA).

[0102] In the flowchart illustrated in Fig. 4, various kinds of control information used for the notification control is read 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, and the current position Pb, the vehicle speed VSPb, and the link ID of the straight traveling vehicle VB. 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.

[0103] In S112, whether or not the right turning vehicle VA which is the host vehicle has detected another vehicle traveling in the straight direction toward the intersection CS in the lane opposite to the lane in which the right turning vehicle VA is present, that is, the straight traveling vehicle VB is determined. 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.

[0104] In S113, whether or not a right turn intention of the right turning vehicle VA has been detected is determined. 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.

[0105] In S114, the current position Pa of the right turning vehicle VA on the road map is specified.

[0106] In S115, whether or not the right turning vehicle VA has entered the intersection area ACS is determined. Specifically, 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, it is determined that the right turning vehicle VA has entered the intersection area ACS, and the processing proceeds to S116. On the other hand, in a case where the right turning vehicle VA is located at a position farther from the intersection center CTR than the outer edge of the intersection area ACS, the right turning vehicle VA is determined not to have arrived at the intersection area ACS and to be located outside the intersection area ACS, and this control is ended.

[0107] In S116, the information presentation processing is performed. The information presentation processing follows a procedure illustrated in the flowchart in Fig. 5.

[0108] In S117, the alarm processing is performed. The alarm processing follows a procedure illustrated in the flowchart in Fig. 6.

[0109] In S118, whether or not the right turning vehicle VA has passed the intersection CS is determined. The determination of whether or not 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.

[0110] In the flowchart illustrated in Fig. 5, various kinds of control information used for the information presentation processing is read 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.

[0111] In S212, the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map are specified.

[0112] In S213, whether or not the right turning vehicle VA is located outside the predicted collision area ACP is determined. Specifically, 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), the right turning vehicle VA is determined to be located outside the predicted collision area ACP, and the processing proceeds to S214. 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, whether or not the operation of the right turn signal is being continued may be determined in addition to the processing in S213, and the processing in and after S214 may be performed 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, the right turning vehicle VA is determined not to be located outside the predicted collision area ACP, and the information presentation processing is ended.

[0113] In S214, the vehicle speed VSPa of the right turning vehicle VA is read.

[0114] In S215, whether or not the vehicle speed VSPa of the right turning vehicle VA is equal to or less than a predetermined vehicle speed VSP1 is determined. 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 or not 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 the 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.

[0115] 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, it is determined that a notification issuance timing for the information presentation 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, the processing in and after S216 is performed, and whether or not the first predetermined notification issuance condition has been established is determined in the present embodiment.

[0116] In S216, 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") is calculated. 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.

[0117] In S217, the vehicle speed VSPb of the straight traveling vehicle VB is read.

[0118] In S218, the information presentation distance Dth1 is calculated. 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.

[0119] In S219, whether or not 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 is determined. 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.

[0120] In S220, the notification issuance for the information presentation is performed.

[0121] In the flowchart illustrated in Fig. 6, various kinds of control information used for the alarm processing is read 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.

[0122] In S312, the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map are specified.

[0123] In S313, whether or not the right turning vehicle VA is located inside the predicted collision area ACP is determined. Specifically, 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, the right turning vehicle VA is determined to be located inside the predicted collision area ACP, and 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, the right turning vehicle VA is determined not to be located inside the predicted collision area ACP, and 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.

[0124] In S314, the vehicle speed VSPa of the right turning vehicle VA is read.

[0125] In S315, whether or not the vehicle speed VSPa of the right turning vehicle VA is higher than the predetermined vehicle speed VSP1 is determined. 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, whether or not 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 is determined, and in a case where the vehicle speed VSPa is greater than the vehicle speed VSP1, the driver of the right turning vehicle VA is determined not to be 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, it is determined that the notification should be issued for the information presentation in the situation, and the alarm processing is ended.

[0126] In this manner, a notification issuance timing for an alarm is determined to have 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, the processing in and after S316 is performed, and whether or not the second predetermined notification issuance condition is established is determined.

[0127] In S316, the intersection arrival distance Db of the straight traveling vehicle VB is calculated.

[0128] In S317, the vehicle speed VSPb of the straight traveling vehicle VB is read.

[0129] In S318, the alarm distance Dth2 is calculated. 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.

[0130] In S319, whether or not 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 is determined. 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.

[0131] In S320, the notification issuance for the alarm is performed.(Content of Notification Control in Straight Traveling Vehicle)

[0132] Figs. 7 to 9 are flowcharts illustrating content of notification control performed by the controller 101b included in the straight traveling vehicle VB. 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 is detected in a road 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.

[0133] Each process performed by the controller 101a and the controller 101b in regard to the notification control corresponds to each other. Therefore, detailed description of the processes that are similar for both will be omitted in the following description.

[0134] In the flowchart illustrated in Fig. 7, various kinds of control information used for the notification control is read (S411), another vehicle that is present in the right turn lane L11 in the opposite lanes, that is, the right turning vehicle VA is detected (S412), and whether or not the right turn intention of the right turning vehicle VA, which is another vehicle, has been detected is then determined in S413. After the right turn intention is detected, the current position Pa of the right turning vehicle VA on the road map is specified (S414), and whether or not the right turning vehicle VA has entered the intersection area ACS is determined (S415). The procedure in and after S416 is executed in a case where the right turning vehicle VA has entered the intersection area ACS, or this control is ended in a case where the right turning vehicle VA has not entered the intersection area ACS. The information presentation processing is executed in S416, and the alarm processing is executed in S417. The information presentation processing and the alarm processing are repeated until the right turning vehicle VA passes the intersection area ACS.

[0135] In the flowchart illustrated in Fig. 8, 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, are read (S511), and the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map are specified (S512). In S513, whether or not the right turning vehicle VA, which is another vehicle, is located outside the predicted collision area ACP is determined, and in a case where the right turning vehicle VA is determined to be located outside the predicted collision area ACP, the vehicle speed VSPa of the right turning vehicle VA is read (S514), and whether or not the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the predetermined vehicle speed VSP1 is determined (S515). The processing in and after S516 is performed 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 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, whether or not the operation of the right turn signal is being continued may be determined in addition to the processing in S513, and the processing in and after S514 may be executed in a case where the operation of the right turn signal is being continued. Then, the intersection arrival distance Db of the straight traveling vehicle VB, which is the host vehicle, is calculated (S516), the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) is read (S517), and the information presentation distance Dth1 is calculated (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.

[0136] In the flowchart illustrated in Fig. 9, 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 is read (S611), and the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map are specified (S612). Whether or not the right turning vehicle VA, which is another vehicle, is located inside the predicted collision area ACP, is determined in S613, and in a case where the right turning vehicle VA is determined not to be located inside the predicted collision area ACP, the vehicle speed VSPa of the right turning vehicle VA is read (S614), and whether or not the vehicle speed VSPa of the right turning vehicle VA is greater than the predetermined vehicle speed VSP1 is determined (S615). The processing in and after S616 is performed 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 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 intersection arrival distance Db of the straight traveling vehicle VB, which is a host vehicle, is calculated (S616), the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) is read (S617), and the alarm distance Dth2 is calculated (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.(Description of Actions and Effects)

[0137] The vehicle notification system 1 according to the present embodiment has the aforementioned configuration. Effects obtained by the present embodiment will be described below.

[0138] 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.

[0139] 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.

[0140] 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 distance P1 or has approached the position closer to the predicted collision point CPP.

[0141] 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.

[0142] 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.

[0143] 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.

[0144] 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.

[0145] 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.

[0146] 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.

[0147] 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.

[0148] 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 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.

[0149] 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.

[0150] 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.

[0151] 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 the drawings) defining the outer edge of the predicted collision area ACP to the straight traveling vehicle VB is employed as the distance Db from the intersection CS to the straight traveling vehicle VB. The 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 distance Db.

[0152] 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.

[0153] 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 crossing lane L31 intersecting the right turn lane L11 from among lanes leading to the intersection CS to which the right turning vehicle VA is directed.

[0154] Fig. 15 is a schematic diagram schematically illustrating an example of a traffic situation assumed as a target of notification issuance by a notification system according to another embodiment of the present invention.

[0155] In the present embodiment, a traffic situation in which a crossing vehicle VC is also a target of notification issuance in addition to the right turning vehicle VA and the straight traveling vehicle VB in the example illustrated in Fig. 12 and the right turning vehicle VA, the straight traveling vehicle VB, and the crossing vehicle VC are traveling toward the intersection CS is assumed. Although the intersection CS and the road R leading to the intersection CS have configurations similar to those in the example illustrated in Fig. 12, a traffic signal to regulate passing of vehicles (including the crossing vehicle VC) that enter the intersection CS from the crossing lane L31 is not installed in the present embodiment. Therefore, there is a concern that the timing at which the crossing vehicle VC 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 the right turning vehicle VA, the straight traveling vehicle VB, and the crossing vehicle VC may be brought into contact with or collide against each other at the intersection CS in the illustrated situation.

[0156] In such a situation, the notification system 1 monitors the relative positional relationship between the right turning vehicle VA and the crossing vehicle VC 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 the right turning vehicle VA displays its right turn intention. 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 VC is executed at an appropriate timing before the right turning vehicle VA passes the intersection CS after approaching the intersection CS.

[0157] The processing performed by the right turning vehicle VA on the basis of the relationship with the crossing vehicle VC in regard to the notification control according to the present embodiment has content similar to that performed by the right turning vehicle VA on the basis of the relationship with the straight traveling vehicle VB in the previous embodiment. The processing performed by the crossing vehicle VC on the basis of the relationship with the turning vehicle VA is similar to that performed by the straight traveling vehicle VB on the basis of the relationship with the right turning vehicle VA in the previous embodiment.

[0158] The content of the notification control according to the present embodiment will be schematically described with reference to Figs. 16 and 17.

[0159] As illustrated in Fig. 16, the notification system detects the right turn intention of the right turning vehicle VA on the basis of the operating status of the right turn signal or the like, then detects that the right turning vehicle VA is present at the first predetermined position P1 in the traveling lane (that is, the right turn lane L11) or a position closer to the intersection center CTR than the first predetermined position P1, and sets the timing of this detection as a first notification issuance timing. The notification system sets an intersection area ACS that superimposes a path TRa along which the right turning vehicle VA travels at the time of passing the intersection CS and detects that the right turning vehicle VA is present 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 by the arrival of the right turning vehicle VA at the intersection area ACS or the entrance thereof to the intersection area ACS after displaying the right turn intention. The intersection area ACS is set as a circular area that includes, for example, the first predetermined position P1 on its outer edge and has a predetermined radius around the intersection center CTR at the center.

[0160] Similarly to the above description, the point at which the path TRa along which the right turning vehicle VA travels at the time of passing the intersection CS and a path TRc along which the crossing vehicle VC travels at the time of passing the intersection CS intersect is assumed to be a "predicted collision point" CPP of the right turning vehicle VA with respect to the crossing vehicle VC, traveling of the right turning vehicle VA toward the predicted collision point CPP at a position closer to the predicted collision point CPP than the first predetermined position P1 or presence thereof at a position closer to the predicted collision point CPP than the second predetermined position P2 between the first predetermined position P1 and the predicted collision point CPP is detected on the basis of the current position Pa of the right turning vehicle VA on the road map, and the timing of the detection is set as a second notification issuance timing.

[0161] The "predicted collision point" CPP of the right turning vehicle VA with respect to the crossing vehicle VC may be set separately from the predicted collision point with respect to the straight traveling vehicle VB, that is, the point at which the traveling path TRa of the right turning vehicle VA and the traveling path TRb (Fig. 12) of the straight traveling vehicle VB intersect or may be set as a common point. In a case where the predicted collision point CPP is set as a common point, a range in which the opposite straight lane L22 and the crossing lane L31 overlap in the intersection CS or the intersection area ACS, for example, is defined, and the point at the center of the range is set as the predicted collision point CPP.

[0162] As illustrated in Fig. 17, 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 thereof at a position closer to the predicted collision point CPP than the second predetermined position P2 is detected on the basis of traveling of the right turning vehicle VA at a vehicle speed higher than a predetermined vehicle speed toward the predicted collision point CPP inside the intersection area ACS or presence thereof inside the predicted collision area ACP after entering the intersection area ACS. 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.

[0163] Furthermore, the notification issuance in a predetermined mode is executed at each timing under a condition that a notification issuance condition defined in advance in regard to the position Pc of the crossing vehicle VC is established at each of the first and second notification issuance timings. Specifically, the notification issuance for the information presentation, which is the first predetermined mode, is executed under the condition that the first predetermined notification issuance condition is established at the first notification issuance timing, and the notification issuance for the alarm, which is the second predetermined mode, is performed under the condition that the second predetermined notification issuance condition is established at the second notification issuance timing.

[0164] The notification issuance for the information presentation is notification issuance for relatively low urgency in regard to collision between the right turning vehicle VA and the crossing vehicle VC and is notification issuance to promote the right turning vehicle VA to recognize the presence of the crossing vehicle VC traveling toward the intersection CS in the crossing lane L31. On the other hand, the notification issuance for the alarm is notification issuance for promoting recognition of higher urgency in regard to collision between the right turning vehicle VA and the crossing vehicle VC and is notification issuance that is more prominent and more visually or auditorily appealing to the driver as compared with the notification issuance for the information presentation.

[0165] The first predetermined notification issuance condition is that the crossing vehicle VC is located at the relatively long information presentation distance Dth1 from the intersection CS or is present at a position closer to the intersection CS than the information predetermined distance Dth1, and the second predetermined notification issuance condition is that the crossing vehicle VC is located at the alarm distance Dth2, which is shorter than the information presentation distance Dth1, from the intersection CS or is present at a position closer to the intersection CS than the alarm distance Dth2.

[0166] The information presentation distance Dth1 in the relationship with the crossing vehicle VC is calculated by (1) above as a distance required by the crossing vehicle VC to stop at the first predetermined deceleration degree DEC1 after the notification issuance, on the basis of a vehicle speed VSPc of the crossing vehicle VC at the first notification issuance timing and the first predetermined deceleration degree DEC1. On the other hand, the alarm distance Dth2 is calculated by (2) above as a distance required by the crossing vehicle VC to stop at the second predetermined deceleration degree DEC2 after the notification issuance on the basis of the vehicle speed VSPc of the crossing vehicle VC at the second notification issuance timing and the second predetermined deceleration degree DEC2.

[0167] The notification provided by the notification system may be targeted at all the related traffic participants or may be targeted at only some of the traffic participants. In a case where the right turning vehicle VA, the straight traveling vehicle VB, and the crossing vehicle VC are present as the traffic participants, for example, all the vehicles VA, VB, and VC may be targets of the notification, or only the crossing vehicle VC in addition to the right turning vehicle VA may be the target of the notification. In the case where both the straight traveling vehicle VB and the crossing vehicle VC are the targets, the notification control and the information presentation processing and the alarm processing included in the notification control may be executed separately or in parallel by the controllers of the vehicles VB and VC.

[0168] 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

[0169] 1 Vehicle notification system; 101a, 101b Controller; 111a, 111b Position sensor; 112a, 112b Vehicle speed sensor; 113a, 113b Right turn signal switch; 121a, 121b Transmitter; 122a, 122b Receiver; 131a, 131b HMI device; VA Right turning vehicle; VB Straight traveling vehicle; VC Crossing vehicle.

Examples

Embodiment Construction

[0038]Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Overall Configuration of Vehicle Notification System)

[0039]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.

[0040]In the present embodiment, a traffic situation where a vehicle (hereinafter, referred to as a "right turning vehicle") VA traveling toward an intersection on a left-hand traffic road and another vehicle (hereinafter, referred to as a "straight traveling vehicle") VB traveling in a straight direction toward the intersection 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 ...

BACKGROUND OF THE INVENTIONField of the Invention

[0001] The present invention relates 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.Citation ListPatent Document

[0004] Patent Document 1: Japanese Patent Laid-Open No. 2009-265832

[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.SUMMARY OF THE INVENTION

[0008] Thus, an object of the present invention is to provide a vehicle notification system that contributes to a further improvement in traffic safety.

[0009] To solve the above-mentioned problem, a vehicle notification system according to one aspect of the present invention is configured to issue a notification to traffic participants including a first vehicle that is present in a traveling lane leading to an intersection and turns right or left at the intersection and a second vehicle that travels in a straight direction toward the intersection in a lane opposite to the traveling lane.

[0010] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, 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 while turning right or left at the intersection, a first vehicle behavior detection unit that detects, on a basis of the current position of the first vehicle specified by the first vehicle position specification unit, that the first vehicle is present at a first predetermined position in the traveling lane or a position closer to an intersection center than the first predetermined position after the direction-change-intention detection unit detects the direction change intention, the intersection center being a center position of the intersection, a second vehicle behavior detection unit that regards, as a predicted collision point, a point at which a path along which the first vehicle travels when passing the intersection and a path along which the second vehicle travels when passing the intersection intersect and detects, on the basis of the current position of the first vehicle, that the first vehicle is traveling at a position closer to the predicted collision point than the first predetermined position toward the predicted collision point or that the first vehicle is present at a position closer to the predicted collision point than a second predetermined position between the first predetermined position and the predicted collision point, a first notification issuing unit that issues a notification in a first predetermined mode to the traffic participants under a condition that the second vehicle is located at a first predetermined distance from the intersection or is present at a location closer to the intersection than the first predetermined distance in a case where the first vehicle behavior detection unit detects that the first vehicle is present at the first predetermined position or the position that is closer to the intersection center than the first predetermined position, and a second notification issuing unit that issues a notification in a second predetermined mode that is different from the first predetermined mode to the traffic participants under a condition that the second vehicle is located at a second predetermined distance from the intersection or is present at a position closer to the intersection than the second predetermined distance in a case where the second vehicle behavior detection unit detects that the first vehicle is traveling at a position closer to the predicted collision point than the first predetermined position or that the first vehicle is present at a position closer to the predicted collision point than the second predetermined position, the second predetermined distance being shorter than the first predetermined distance.

[0011] The first notification issuing unit and the second notification issuing unit may be configured to issue the respective notifications using mutually different displays or sounds.

[0012] An intersection area that overlaps the path along which the first vehicle travels when passing the intersection and that includes the first predetermined position on an outer edge and a predicted collision area that includes the predicted collision point therein and includes the second predetermined position on an outer edge may be set in an associated manner in the road map.

[0013] In this case, the first vehicle behavior detection unit may be configured to detect that the first vehicle is present inside the intersection area after the detection of the direction change intention, and the second vehicle behavior detection unit may be configured to detect that the first vehicle is traveling toward the predicted collision point inside the intersection area or is present inside the predicted collision area.

[0014] The first vehicle behavior detection unit may be detect that the first vehicle is stopping or is in a low-speed traveling state at a predetermined vehicle speed or less inside the intersection area after the detection of the direction change intention.

[0015] In this case, the first notification issuing unit may be configured to issue the notification in the first predetermined mode under the condition that the second vehicle is located at the first predetermined distance from the intersection or is present at the position closer to the intersection than the first predetermined distance in the case where the first vehicle is stopping or is in the low-speed traveling state inside the intersection area.

[0016] The vehicle notification system may further include a vehicle speed detection unit that detects a vehicle speed of the second vehicle.

[0017] In this case, the first notification issuing unit may be configured to calculate the first predetermined distance on a basis of the vehicle speed of the second vehicle detected by the vehicle speed detection unit, and the second notification issuing unit may be configured to calculate the second predetermined distance on the basis of the vehicle speed of the second vehicle detected by the vehicle speed detection unit.

[0018] The first notification issuing unit may be configured to calculate the first predetermined distance on a basis of the vehicle speed of the second vehicle and the first predetermined deceleration degree set in advance.

[0019] The second notification issuing unit may be configured to calculate the second predetermined distance on a basis of the vehicle speed of the second vehicle and the second predetermined deceleration degree set in advance as a deceleration degree that is higher than the first predetermined deceleration degree.

[0020] The vehicle notification system may further include a deceleration degree learning unit that learns an actual deceleration degree when the second vehicle decelerates in response to the notification issuance in the second predetermined mode and calculates a learning value that indicates the actual deceleration degree.

[0021] In this case, the vehicle notification system may further include a deceleration degree correcting unit that corrects at least one of the first predetermined deceleration degree and the second predetermined deceleration degree on a basis of the learning value calculated by the deceleration degree learning unit.

[0022] The direction-change-intention detection unit may be configured to detect the direction change intention in a case where the direction change intention of the first vehicle has continued for a predetermined period of time or more.

[0023] The notification issuance in the second predetermined mode by the second notification issuing unit may be prioritized over the notification issuance in the first predetermined mode by the first notification issuing unit.

[0024] In another aspect of the present invention, a vehicle notification system is configured to issue a notification related to other traffic participants including vehicles other than a host vehicle that turns right or left at an intersection.

[0025] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, a direction-change-intention detection unit that detects a direction change intention of the host vehicle while turning right or left at the intersection, a host vehicle position specification unit that specifies a current position of the host vehicle on the road map, an other vehicle information acquisition unit that acquires vehicle information including position information about another vehicle through communication with another vehicle, when there is another vehicle traveling in a straight direction toward the intersection in a lane opposite to the traveling lane where the host vehicle is present, an other vehicle position specification unit that specifies a current position of another vehicle on the road map on a basis of the vehicle information of another vehicle acquired by the other vehicle information acquisition unit, a first vehicle behavior detection unit that detects, on a basis of the current position of the host vehicle specified by the host vehicle position specification unit, that the host vehicle is present at a first predetermined position in the traveling lane or a position closer to an intersection center that is a center position of the intersection than the first predetermined position after the direction-change-intention detection unit detects the direction change intention, a second vehicle behavior detection unit that regards, as a predicted collision point, a point at which a path along which the host vehicle travels when passing the intersection and a path along which another vehicle travels when passing the intersection intersect and detects that the host vehicle is traveling at a position closer to the predicted collision point than the first predetermined position toward the predicted collision point or that the host vehicle is present at a position closer to the predicted collision point than a second predetermined position between the first predetermined position and the predicted collision point, a first notification issuing unit that issues a notification in a first predetermined mode under a condition that another vehicle is located at a first predetermined distance from the intersection or is present at a location closer to the intersection than the first predetermined distance in a case where the first vehicle behavior detection unit detects that the host vehicle is present at the first predetermined position or the position that is closer to the intersection center than the first predetermined position, and a second notification issuing unit that issues a notification in a second predetermined mode that is different from the first predetermined mode under a condition that another vehicle is located at a second predetermined distance that is shorter than the first predetermined distance from the intersection or is present at a position closer to the intersection than the second predetermined distance in a case where the second vehicle behavior detection unit detects that the host vehicle is traveling at a position closer to the predicted collision point than the first predetermined position or that the host vehicle is present at a position closer to the predicted collision point than the second predetermined position.

[0026] The vehicle notification system may further include a specific vehicle information transmitting unit that transmits specific vehicle information to another vehicle. The specific vehicle information may indicate implementation of at least one of the notifications by the first notification issuing unit and the second notification issuing unit.

[0027] In a further aspect of the present invention, a vehicle notification system is configured to issue a notification related to other traffic participants including vehicles other than a host vehicle that travels in a straight direction toward an intersection.

[0028] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, a host vehicle position specification unit that specifies a current position of the host vehicle on the road map, an other vehicle information acquisition unit that acquires vehicle information including position information about another vehicle through communication with another vehicle, when there is another vehicle in a lane opposite to the lane where the host vehicle travels, a direction-change-intention detection unit that detects a direction change intention of another vehicle while turning right or left at the intersection on a basis of the vehicle information of another vehicle acquired by the other vehicle information acquisition unit, an other vehicle position specification unit that specifies a current position of another vehicle on the road map based on the vehicle information of another vehicle, a first vehicle behavior detection unit that detects, on a basis of the current position of another vehicle specified by the other vehicle position specification unit, that another vehicle is present at a first predetermined position in the opposite lane or a position closer to an intersection center that is a center position of the intersection than the first predetermined position after the direction-change-intention detection unit detects the direction change intention, a second vehicle behavior detection unit that regards, as a predicted collision point, a point at which a path along which the host vehicle travels when passing the intersection and a path along which another vehicle travels when passing the intersection intersect and detects that another vehicle is traveling at a position closer to the predicted collision point than the first predetermined position toward the predicted collision point or that another vehicle is present at a position closer to the predicted collision point than a second predetermined position between the first predetermined position and the predicted collision point, a first notification issuing unit that issues a notification in a first predetermined mode under a condition that the host vehicle is located at a first predetermined distance from the intersection or is present at a location closer to the intersection than the first predetermined distance in a case where the first vehicle behavior detection unit detects that another vehicle is present at the first predetermined position or the position that is closer to the intersection center than the first predetermined position, and a second notification issuing unit that issues a notification in a second predetermined mode that is different from the first predetermined mode under a condition that the host vehicle is located at a second predetermined distance that is shorter than the first predetermined distance from the intersection or is present at a position closer to the intersection than the second predetermined distance in a case where the second vehicle behavior detection unit detects that another vehicle is traveling at a position closer to the predicted collision point than the first predetermined position or that another vehicle is present at a position closer to the predicted collision point than the second predetermined position.

[0029] The vehicle notification system may further include a specific vehicle information transmitting unit that transmits specific vehicle information to another vehicle. The specific vehicle information may indicate implementation of at least one of the notifications by the first notification issuing unit and the second notification issuing unit.

[0030] In a still further aspect of the present invention, a vehicle notification system is configured to issue a notification to traffic participants including a first vehicle and a second vehicle, the first vehicle being present in a traveling lane leading to an intersection and turning right or left at the intersection, and the second vehicle traveling toward the intersection in a lane leading to the intersection other than the traveling lane.

[0031] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, 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 while turning right or left at the intersection, a first issuance timing setting unit that sets a first issuance timing according to a relative position of the first vehicle with respect to an intersection area based on the current position of the first vehicle specified by the first vehicle position specification unit, the intersection area overlapping the path along which the first vehicle travels when passing the intersection and being set in association with the road map, a second issuance timing setting unit that sets a second issuance timing according to a behavior of the first vehicle within the intersection area, after the first issuance timing has been set by the first issuance timing setting unit, and a notification issuing unit that issues a notification in a predetermined mode to the traffic participants under a condition that issuance conditions defined with respect to a position of the second vehicle are satisfied at each of the first issuance timing set by the first issuance timing setting unit and the second issuance timing set by the second issuance timing setting unit.

[0032] In a still further aspect of the present invention, a vehicle notification system is configured to issue a notification to traffic participants including a first vehicle and a second vehicle, the first vehicle being present in a traveling lane leading to an intersection and turning right or left at the intersection, and the second vehicle traveling toward the intersection in a lane leading to the intersection other than the traveling lane.

[0033] In this aspect, the vehicle notification system may include a road map storage unit that stores a road map including the intersection, 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 while turning right or left at the intersection, a first issuance timing setting unit that sets a first issuance timing when the first vehicle is present in an intersection area, the intersection area overlapping the path along which the first vehicle travels when passing the intersection and being set in association with the road map, a second issuance timing setting unit that sets a second issuance timing when the first vehicle is in a predicted collision area, the predicted collision area being different from the intersection area and including a predicted collision point at which a path along which the first vehicle travels when passing the intersection and a path along which the second vehicle travels when passing the intersection intersect, and a notification issuing unit that issues a notification in a predetermined mode to the traffic participants under a condition that issuance conditions defined with respect to a position of the second vehicle are satisfied at each of the first issuance timing set by the first issuance timing setting unit and the second issuance timing set by the second issuance timing setting unit.

[0034] The second vehicle may be a straight traveling vehicle traveling towards the intersection in a lane opposite to the traveling lane.

[0035] The second vehicle may be a crossing vehicle traveling towards the intersection in a lane intersecting the traveling lane.

[0036] According to one aspect of the present invention, it is possible to realize an appropriate notification in an appropriate mode in accordance with a relative relationship between a first vehicle that turns right or left at an intersection and a second vehicle that travels in a straight direction toward the intersection in an opposite lane in a situation where the first vehicle and the second vehicle are present, and to promote a driver to accurately recognize urgency of the circumstances.BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Fig. 1 is a schematic diagram illustrating an overall configuration of a vehicle notification system according to an embodiment of the present embodiment; 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 executed by the right turning vehicle; Fig. 5 is a flowchart illustrating content of the notification control (information presentation processing) executed by the right turning vehicle; Fig. 6 is a flowchart illustrating content of the notification control (alarm processing) executed by the right turning vehicle; Fig. 7 is a flowchart illustrating an overall flow of notification control executed by the straight traveling vehicle; Fig. 8 is a flowchart illustrating content of the notification control (information presentation processing) executed by the straight traveling vehicle; Fig. 9 is a flowchart illustrating content of the notification control (alarm processing) executed by the straight traveling vehicle; 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 schematically illustrating an example of a traffic situation assumed as 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 issuance timing of information presentation; Fig. 13 is a schematic diagram illustrating a relationship between the right turning vehicle and the straight traveling vehicle at an issuance timing of an alarm; Fig. 14 is a schematic diagram illustrating a situation after the straight traveling vehicle passes an intersection; Fig. 15 is a schematic diagram schematically illustrating another example of a traffic situation assumed as a target of a notification; Fig. 16 is a schematic diagram illustrating a relationship among the right turning vehicle, the straight traveling vehicle, and a crossing vehicle at an issuance timing of information presentation; and Fig. 17 is a schematic diagram illustrating a relationship among the right turning vehicle, the straight traveling vehicle, and the crossing vehicle at an issuance timing of an alarm. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] Hereinafter, embodiments of the present invention will be described with reference to the drawings.(Overall Configuration of Vehicle Notification System)

[0039] 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.

[0040] In the present embodiment, a traffic situation where a vehicle (hereinafter, referred to as a "right turning vehicle") VA traveling toward an intersection on a left-hand traffic road and another vehicle (hereinafter, referred to as a "straight traveling vehicle") VB traveling in a straight direction toward the intersection 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 toward an intersection and a straight traveling vehicle traveling toward the intersection in an opposite lane are present is 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 intersection and should not hinder the straight traveling vehicle traveling in the opposite lane from passing the intersection.

[0041] 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.

[0042] 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.

[0043] 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 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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 high-precision satellite positioning 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).

[0048] 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.

[0049] 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.

[0050] Detection signals from the position sensor 111a, the vehicle speed sensor 112a, and the right turn signal switch 113a are output to the controller 101a, while detection signals from the position sensor 111b, the vehicle speed sensor 112b, and the right turn signal switch 113b are output to the controller 101b.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] Fig. 11 is a schematic diagram schematically illustrating an example of a traffic situation assumed as a notification target according to the present embodiment.

[0056] 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.

[0057] In addition to the right turning vehicle VA and the straight traveling vehicle VB, a vehicle (hereinafter, referred to as a "waiting vehicle") VZ 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 VZ 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 VZ 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 VZ seen from the straight traveling vehicle VB.

[0058] 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. 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.(Internal Configuration of Controller)

[0059] 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 Fig. 11 as needed.

[0060] As illustrated in Fig. 2, the controller 101a 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, and a second notification issuing unit B119a. A function of each of these units B111a to B119a 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.

[0061] 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 of the host vehicle 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.

[0062] 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 of another vehicle 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.

[0063] 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. In the road map, identifiers (hereinafter, referred to as "link IDs") corresponding to lanes leading to the intersection CS, such as the right turn lanes L11 and L21 and the straight lanes L12 and L22, are assigned and are stored 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 on the road map.

[0064] 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 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.

[0065] 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.

[0066] 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.

[0067] 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).

[0068] In the present embodiment, an intersection area ACS is set as a determination criterion to recognize the relative positional relationship between the right turning vehicle VA and 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 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 twodotted 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.

[0069] 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.

[0070] 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.

[0071] 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 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.

[0072] 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).

[0073] The first notification issuing unit B118a outputs a command signal to issue a notification in a 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 established at a timing at which 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.

[0074] 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.

[0075] The HMI device 131a that has received the command signal from the first notification issuing unit B118a 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.

[0076] 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.

[0077] 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.

[0078] 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 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.

[0079] The first notification issuing unit B118a and the second notification issuing unit B119a can also provide a notification that the notification in each mode has been issued to the straight traveling vehicle VB via the transmitter 121a in accordance with the output of the command signal to the HMI device 131a and promote a notification to be issued in an appropriate mode in accordance with urgency in regard to collision against the host vehicle (that is, the right turning vehicle VA).

[0080] Fig. 10 is an explanatory diagram illustrating a method of calculating the information presentation distance Dth1 and the alarm distance Dth2.

[0081] 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.

[0082] 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

[0083] 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 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

[0084] 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.

[0085] As illustrated in Fig. 3, the controller 101b 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, and a second notification issuing unit B119b. Differences between an internal configuration of the controller 101b and that of the controller 101a will be mainly described below.

[0086] 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 thereof is based on an output signal from the position sensor 111b included in the straight traveling vehicle VB.

[0087] 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 thereof 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.

[0088] 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 the assigned link ID of each lane leading to 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. Although the road maps stored in the road map storage units B113b and B113a may have different levels of accuracy, both the maps employ an accuracy that is compatible with satellite positioning using GNSS in the present embodiment.

[0089] The right turn intention detection unit B114b is adapted to detect a right turn intention of the right turning vehicle VA, and the detection thereof is based on 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 or 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. 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.

[0090] 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 122a.

[0091] 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.

[0092] The size and the shape of the intersection area ACS may be the same or different between the controller 101a and the controller 101b. 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.

[0093] 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.

[0094] 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.

[0095] 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. 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.

[0096] 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.

[0097] The second notification issuing unit B119b outputs 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. 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.

[0098] 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.

[0099] 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.

[0100] 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 has been issued via the transmitter 121b in accordance with the output of the command signal to the HMI device 131b.(Content of Notification Control in Right Turning Vehicle)

[0101] Figs. 4 to 6 are flowcharts illustrating content of notification control performed by the controller 101a included in the right turning vehicle VA. 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 is detected in a road in front of the host vehicle (that is, the right turning vehicle VA).

[0102] In the flowchart illustrated in Fig. 4, various kinds of control information used for the notification control is read 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, and the current position Pb, the vehicle speed VSPb, and the link ID of the straight traveling vehicle VB. 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.

[0103] In S112, whether or not the right turning vehicle VA which is the host vehicle has detected another vehicle traveling in the straight direction toward the intersection CS in the lane opposite to the lane in which the right turning vehicle VA is present, that is, the straight traveling vehicle VB is determined. 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.

[0104] In S113, whether or not a right turn intention of the right turning vehicle VA has been detected is determined. 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.

[0105] In S114, the current position Pa of the right turning vehicle VA on the road map is specified.

[0106] In S115, whether or not the right turning vehicle VA has entered the intersection area ACS is determined. Specifically, 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, it is determined that the right turning vehicle VA has entered the intersection area ACS, and the processing proceeds to S116. On the other hand, in a case where the right turning vehicle VA is located at a position farther from the intersection center CTR than the outer edge of the intersection area ACS, the right turning vehicle VA is determined not to have arrived at the intersection area ACS and to be located outside the intersection area ACS, and this control is ended.

[0107] In S116, the information presentation processing is performed. The information presentation processing follows a procedure illustrated in the flowchart in Fig. 5.

[0108] In S117, the alarm processing is performed. The alarm processing follows a procedure illustrated in the flowchart in Fig. 6.

[0109] In S118, whether or not the right turning vehicle VA has passed the intersection CS is determined. The determination of whether or not 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.

[0110] In the flowchart illustrated in Fig. 5, various kinds of control information used for the information presentation processing is read 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.

[0111] In S212, the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map are specified.

[0112] In S213, whether or not the right turning vehicle VA is located outside the predicted collision area ACP is determined. Specifically, 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), the right turning vehicle VA is determined to be located outside the predicted collision area ACP, and the processing proceeds to S214. 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, whether or not the operation of the right turn signal is being continued may be determined in addition to the processing in S213, and the processing in and after S214 may be performed 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, the right turning vehicle VA is determined not to be located outside the predicted collision area ACP, and the information presentation processing is ended.

[0113] In S214, the vehicle speed VSPa of the right turning vehicle VA is read.

[0114] In S215, whether or not the vehicle speed VSPa of the right turning vehicle VA is equal to or less than a predetermined vehicle speed VSP1 is determined. 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 or not 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 the 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.

[0115] 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, it is determined that a notification issuance timing for the information presentation 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, the processing in and after S216 is performed, and whether or not the first predetermined notification issuance condition has been established is determined in the present embodiment.

[0116] In S216, 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") is calculated. 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.

[0117] In S217, the vehicle speed VSPb of the straight traveling vehicle VB is read.

[0118] In S218, the information presentation distance Dth1 is calculated. 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.

[0119] In S219, whether or not 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 is determined. 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.

[0120] In S220, the notification issuance for the information presentation is performed.

[0121] In the flowchart illustrated in Fig. 6, various kinds of control information used for the alarm processing is read 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.

[0122] In S312, the current positions Pa and Pb of the right turning vehicle VA and the straight traveling vehicle VB on the road map are specified.

[0123] In S313, whether or not the right turning vehicle VA is located inside the predicted collision area ACP is determined. Specifically, 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, the right turning vehicle VA is determined to be located inside the predicted collision area ACP, and 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, the right turning vehicle VA is determined not to be located inside the predicted collision area ACP, and 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.

[0124] In S314, the vehicle speed VSPa of the right turning vehicle VA is read.

[0125] In S315, whether or not the vehicle speed VSPa of the right turning vehicle VA is higher than the predetermined vehicle speed VSP1 is determined. 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, whether or not 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 is determined, and in a case where the vehicle speed VSPa is greater than the vehicle speed VSP1, the driver of the right turning vehicle VA is determined not to be 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, it is determined that the notification should be issued for the information presentation in the situation, and the alarm processing is ended.

[0126] In this manner, a notification issuance timing for an alarm is determined to have 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, the processing in and after S316 is performed, and whether or not the second predetermined notification issuance condition is established is determined.

[0127] In S316, the intersection arrival distance Db of the straight traveling vehicle VB is calculated.

[0128] In S317, the vehicle speed VSPb of the straight traveling vehicle VB is read.

[0129] In S318, the alarm distance Dth2 is calculated. 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.

[0130] In S319, whether or not 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 is determined. 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.

[0131] In S320, the notification issuance for the alarm is performed.(Content of Notification Control in Straight Traveling Vehicle)

[0132] Figs. 7 to 9 are flowcharts illustrating content of notification control performed by the controller 101b included in the straight traveling vehicle VB. 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 is detected in a road 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.

[0133] Each process performed by the controller 101a and the controller 101b in regard to the notification control corresponds to each other. Therefore, detailed description of the processes that are similar for both will be omitted in the following description.

[0134] In the flowchart illustrated in Fig. 7, various kinds of control information used for the notification control is read (S411), another vehicle that is present in the right turn lane L11 in the opposite lanes, that is, the right turning vehicle VA is detected (S412), and whether or not the right turn intention of the right turning vehicle VA, which is another vehicle, has been detected is then determined in S413. After the right turn intention is detected, the current position Pa of the right turning vehicle VA on the road map is specified (S414), and whether or not the right turning vehicle VA has entered the intersection area ACS is determined (S415). The procedure in and after S416 is executed in a case where the right turning vehicle VA has entered the intersection area ACS, or this control is ended in a case where the right turning vehicle VA has not entered the intersection area ACS. The information presentation processing is executed in S416, and the alarm processing is executed in S417. The information presentation processing and the alarm processing are repeated until the right turning vehicle VA passes the intersection area ACS.

[0135] In the flowchart illustrated in Fig. 8, 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, are read (S511), and the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map are specified (S512). In S513, whether or not the right turning vehicle VA, which is another vehicle, is located outside the predicted collision area ACP is determined, and in a case where the right turning vehicle VA is determined to be located outside the predicted collision area ACP, the vehicle speed VSPa of the right turning vehicle VA is read (S514), and whether or not the vehicle speed VSPa of the right turning vehicle VA is equal to or less than the predetermined vehicle speed VSP1 is determined (S515). The processing in and after S516 is performed 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 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, whether or not the operation of the right turn signal is being continued may be determined in addition to the processing in S513, and the processing in and after S514 may be executed in a case where the operation of the right turn signal is being continued. Then, the intersection arrival distance Db of the straight traveling vehicle VB, which is the host vehicle, is calculated (S516), the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) is read (S517), and the information presentation distance Dth1 is calculated (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.

[0136] In the flowchart illustrated in Fig. 9, 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 is read (S611), and the current positions Pb and Pa of the straight traveling vehicle VB and the right turning vehicle VA on the road map are specified (S612). Whether or not the right turning vehicle VA, which is another vehicle, is located inside the predicted collision area ACP, is determined in S613, and in a case where the right turning vehicle VA is determined not to be located inside the predicted collision area ACP, the vehicle speed VSPa of the right turning vehicle VA is read (S614), and whether or not the vehicle speed VSPa of the right turning vehicle VA is greater than the predetermined vehicle speed VSP1 is determined (S615). The processing in and after S616 is performed 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 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 intersection arrival distance Db of the straight traveling vehicle VB, which is a host vehicle, is calculated (S616), the vehicle speed VSPb of the host vehicle (that is, the straight traveling vehicle VB) is read (S617), and the alarm distance Dth2 is calculated (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.(Description of Actions and Effects)

[0137] The vehicle notification system 1 according to the present embodiment has the aforementioned configuration. Effects obtained by the present embodiment will be described below.

[0138] 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.

[0139] 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.

[0140] 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 distance P1 or has approached the position closer to the predicted collision point CPP.

[0141] 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.

[0142] 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.

[0143] 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.

[0144] 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.

[0145] 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.

[0146] 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.

[0147] 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.

[0148] 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 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.

[0149] 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.

[0150] 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.

[0151] 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 the drawings) defining the outer edge of the predicted collision area ACP to the straight traveling vehicle VB is employed as the distance Db from the intersection CS to the straight traveling vehicle VB. The 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 distance Db.

[0152] 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.

[0153] 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 crossing lane L31 intersecting the right turn lane L11 from among lanes leading to the intersection CS to which the right turning vehicle VA is directed.

[0154] Fig. 15 is a schematic diagram schematically illustrating an example of a traffic situation assumed as a target of notification issuance by a notification system according to another embodiment of the present invention.

[0155] In the present embodiment, a traffic situation in which a crossing vehicle VC is also a target of notification issuance in addition to the right turning vehicle VA and the straight traveling vehicle VB in the example illustrated in Fig. 12 and the right turning vehicle VA, the straight traveling vehicle VB, and the crossing vehicle VC are traveling toward the intersection CS is assumed. Although the intersection CS and the road R leading to the intersection CS have configurations similar to those in the example illustrated in Fig. 12, a traffic signal to regulate passing of vehicles (including the crossing vehicle VC) that enter the intersection CS from the crossing lane L31 is not installed in the present embodiment. Therefore, there is a concern that the timing at which the crossing vehicle VC 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 the right turning vehicle VA, the straight traveling vehicle VB, and the crossing vehicle VC may be brought into contact with or collide against each other at the intersection CS in the illustrated situation.

[0156] In such a situation, the notification system 1 monitors the relative positional relationship between the right turning vehicle VA and the crossing vehicle VC 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 the right turning vehicle VA displays its right turn intention. 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 VC is executed at an appropriate timing before the right turning vehicle VA passes the intersection CS after approaching the intersection CS.

[0157] The processing performed by the right turning vehicle VA on the basis of the relationship with the crossing vehicle VC in regard to the notification control according to the present embodiment has content similar to that performed by the right turning vehicle VA on the basis of the relationship with the straight traveling vehicle VB in the previous embodiment. The processing performed by the crossing vehicle VC on the basis of the relationship with the turning vehicle VA is similar to that performed by the straight traveling vehicle VB on the basis of the relationship with the right turning vehicle VA in the previous embodiment.

[0158] The content of the notification control according to the present embodiment will be schematically described with reference to Figs. 16 and 17.

[0159] As illustrated in Fig. 16, the notification system detects the right turn intention of the right turning vehicle VA on the basis of the operating status of the right turn signal or the like, then detects that the right turning vehicle VA is present at the first predetermined position P1 in the traveling lane (that is, the right turn lane L11) or a position closer to the intersection center CTR than the first predetermined position P1, and sets the timing of this detection as a first notification issuance timing. The notification system sets an intersection area ACS that superimposes a path TRa along which the right turning vehicle VA travels at the time of passing the intersection CS and detects that the right turning vehicle VA is present 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 by the arrival of the right turning vehicle VA at the intersection area ACS or the entrance thereof to the intersection area ACS after displaying the right turn intention. The intersection area ACS is set as a circular area that includes, for example, the first predetermined position P1 on its outer edge and has a predetermined radius around the intersection center CTR at the center.

[0160] Similarly to the above description, the point at which the path TRa along which the right turning vehicle VA travels at the time of passing the intersection CS and a path TRc along which the crossing vehicle VC travels at the time of passing the intersection CS intersect is assumed to be a "predicted collision point" CPP of the right turning vehicle VA with respect to the crossing vehicle VC, traveling of the right turning vehicle VA toward the predicted collision point CPP at a position closer to the predicted collision point CPP than the first predetermined position P1 or presence thereof at a position closer to the predicted collision point CPP than the second predetermined position P2 between the first predetermined position P1 and the predicted collision point CPP is detected on the basis of the current position Pa of the right turning vehicle VA on the road map, and the timing of the detection is set as a second notification issuance timing.

[0161] The "predicted collision point" CPP of the right turning vehicle VA with respect to the crossing vehicle VC may be set separately from the predicted collision point with respect to the straight traveling vehicle VB, that is, the point at which the traveling path TRa of the right turning vehicle VA and the traveling path TRb (Fig. 12) of the straight traveling vehicle VB intersect or may be set as a common point. In a case where the predicted collision point CPP is set as a common point, a range in which the opposite straight lane L22 and the crossing lane L31 overlap in the intersection CS or the intersection area ACS, for example, is defined, and the point at the center of the range is set as the predicted collision point CPP.

[0162] As illustrated in Fig. 17, 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 thereof at a position closer to the predicted collision point CPP than the second predetermined position P2 is detected on the basis of traveling of the right turning vehicle VA at a vehicle speed higher than a predetermined vehicle speed toward the predicted collision point CPP inside the intersection area ACS or presence thereof inside the predicted collision area ACP after entering the intersection area ACS. 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.

[0163] Furthermore, the notification issuance in a predetermined mode is executed at each timing under a condition that a notification issuance condition defined in advance in regard to the position Pc of the crossing vehicle VC is established at each of the first and second notification issuance timings. Specifically, the notification issuance for the information presentation, which is the first predetermined mode, is executed under the condition that the first predetermined notification issuance condition is established at the first notification issuance timing, and the notification issuance for the alarm, which is the second predetermined mode, is performed under the condition that the second predetermined notification issuance condition is established at the second notification issuance timing.

[0164] The notification issuance for the information presentation is notification issuance for relatively low urgency in regard to collision between the right turning vehicle VA and the crossing vehicle VC and is notification issuance to promote the right turning vehicle VA to recognize the presence of the crossing vehicle VC traveling toward the intersection CS in the crossing lane L31. On the other hand, the notification issuance for the alarm is notification issuance for promoting recognition of higher urgency in regard to collision between the right turning vehicle VA and the crossing vehicle VC and is notification issuance that is more prominent and more visually or auditorily appealing to the driver as compared with the notification issuance for the information presentation.

[0165] The first predetermined notification issuance condition is that the crossing vehicle VC is located at the relatively long information presentation distance Dth1 from the intersection CS or is present at a position closer to the intersection CS than the information predetermined distance Dth1, and the second predetermined notification issuance condition is that the crossing vehicle VC is located at the alarm distance Dth2, which is shorter than the information presentation distance Dth1, from the intersection CS or is present at a position closer to the intersection CS than the alarm distance Dth2.

[0166] The information presentation distance Dth1 in the relationship with the crossing vehicle VC is calculated by (1) above as a distance required by the crossing vehicle VC to stop at the first predetermined deceleration degree DEC1 after the notification issuance, on the basis of a vehicle speed VSPc of the crossing vehicle VC at the first notification issuance timing and the first predetermined deceleration degree DEC1. On the other hand, the alarm distance Dth2 is calculated by (2) above as a distance required by the crossing vehicle VC to stop at the second predetermined deceleration degree DEC2 after the notification issuance on the basis of the vehicle speed VSPc of the crossing vehicle VC at the second notification issuance timing and the second predetermined deceleration degree DEC2.

[0167] The notification provided by the notification system may be targeted at all the related traffic participants or may be targeted at only some of the traffic participants. In a case where the right turning vehicle VA, the straight traveling vehicle VB, and the crossing vehicle VC are present as the traffic participants, for example, all the vehicles VA, VB, and VC may be targets of the notification, or only the crossing vehicle VC in addition to the right turning vehicle VA may be the target of the notification. In the case where both the straight traveling vehicle VB and the crossing vehicle VC are the targets, the notification control and the information presentation processing and the alarm processing included in the notification control may be executed separately or in parallel by the controllers of the vehicles VB and VC.

[0168] 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

[0169] 1 Vehicle notification system; 101a, 101b Controller; 111a, 111b Position sensor; 112a, 112b Vehicle speed sensor; 113a, 113b Right turn signal switch; 121a, 121b Transmitter; 122a, 122b Receiver; 131a, 131b HMI device; VA Right turning vehicle; VB Straight traveling vehicle; VC Crossing vehicle.

Examples

Embodiment Construction

[0038]Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Overall Configuration of Vehicle Notification System)

[0039]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.

[0040]In the present embodiment, a traffic situation where a vehicle (hereinafter, referred to as a "right turning vehicle") VA traveling toward an intersection on a left-hand traffic road and another vehicle (hereinafter, referred to as a "straight traveling vehicle") VB traveling in a straight direction toward the intersection 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 ...

Claims

1. A vehicle notification system (1) that issues a notification to traffic participants including a first vehicle (VA) that is present in a traveling lane (L11) leading to an intersection (CS) and turns right or left at the intersection (CS) and a second vehicle (VB) that travels in a straight direction toward the intersection (CS) in a lane (L22) opposite to the traveling lane (L11), the vehicle notification system (1) comprising: a road map storage unit (B113a, B113b) that stores a road map including the intersection (CS); 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) while turning right or left at the intersection (CS); a first vehicle behavior detection unit (B116a, B116b) that detects, on a basis of the current position of the first vehicle (VA) specified by the first vehicle position specification unit (B111a, B112b), that the first vehicle (VA) is present at a first predetermined position in the traveling lane (L11) or a position closer to an intersection center (CTR) than the first predetermined position after the direction-change-intention detection unit (B114a, B114b) detects the direction change intention, the intersection center (CTR) being a center position of the intersection (CS); a second vehicle behavior detection unit (B117a, B117b) that regards, as a predicted collision point (CPP), a point at which a path along which the first vehicle (VA) travels when passing the intersection (CS) and a path along which the second vehicle (VB) travels when passing the intersection (CS) intersect and detects, on the basis of the current position of the first vehicle (VA), that the first vehicle (VA) is traveling at a position closer to the predicted collision point (CPP) than the first predetermined position toward the predicted collision point (CPP) or that the first vehicle (VA) is present at a position closer to the predicted collision point (CPP) than a second predetermined position between the first predetermined position and the predicted collision point (CPP); a first notification issuing unit (B118a, B118b) that issues a notification in a first predetermined mode to the traffic participants under a condition that the second vehicle (VB) is located at a first predetermined distance from the intersection (CS) or is present at a location closer to the intersection (CS) than the first predetermined distance in a case where the first vehicle behavior detection unit (B116a, B116b) detects that the first vehicle (VA) is present at the first predetermined position or the position that is closer to the intersection center (CTR) than the first predetermined position; and a second notification issuing unit (B119a, B119b) that issues a notification in a second predetermined mode that is different from the first predetermined mode to the traffic participants under a condition that the second vehicle (VB) is located at a second predetermined distance from the intersection (CS) or is present at a position closer to the intersection (CS) than the second predetermined distance in a case where the second vehicle behavior detection unit (B117a, B117b) detects that the first vehicle (VA) is traveling at a position closer to the predicted collision point (CPP) than the first predetermined position or that the first vehicle (VA) is present at a position closer to the predicted collision point (CPP) than the second predetermined position, the second predetermined distance being shorter than the first predetermined distance.

2. The vehicle notification system (1) according to claim 1, wherein the first notification issuing unit (B118a, B118b) and the second notification issuing unit (B119a, B119b) issue the respective notifications using mutually different displays or sounds.

3. The vehicle notification system (1) according to claim 1 or claim 2, wherein an intersection area (ACS) that overlaps the path along which the first vehicle (VA) travels when passing the intersection (CS) and that includes the first predetermined position on an outer edge and a predicted collision area (ACP) that includes the predicted collision point (CPP) therein and includes the second predetermined position on an outer edge are set in an associated manner in the road map, the first vehicle behavior detection unit (B116a, B116b) detects that the first vehicle (VA) is present inside the intersection area (ACS) after the detection of the direction change intention, and the second vehicle behavior detection unit (B117a, B117b) detects that the first vehicle (VA) is traveling toward the predicted collision point (CPP) inside the intersection area (ACS) or is present inside the predicted collision area (ACP).

4. The vehicle notification system (1) according to claim 3, wherein the first vehicle behavior detection unit (B116a, B116b) detects that the first vehicle (VA) is stopping or is in a low-speed traveling state at a predetermined vehicle speed or less inside the intersection area (ACS) after the detection of the direction change intention, and the first notification issuing unit (B118a, B118b) issues the notification in the first predetermined mode under the condition that the second vehicle (VB) is located at the first predetermined distance from the intersection (CS) or is present at the position closer to the intersection (CS) than the first predetermined distance in the case where the first vehicle (VA) is stopping or is in the low-speed traveling state inside the intersection area (ACS).

5. The vehicle notification system (1) according to any one of claims 1 to 4, further comprising: a vehicle speed detection unit (B115a, 112b) that detects a vehicle speed of the second vehicle (VB), wherein the first notification issuing unit (B118a, B118b) calculates the first predetermined distance on a basis of the vehicle speed of the second vehicle (VB) detected by the vehicle speed detection unit (B115a, 112b), and the second notification issuing unit (B119a, B119b) calculates the second predetermined distance on the basis of the vehicle speed of the second vehicle (VB) detected by the vehicle speed detection unit (B115a, 112b).

6. The vehicle notification system (1) according to claim 5, wherein the first notification issuing unit (B118a, B118b) has a first predetermined deceleration degree set in advance and calculates the first predetermined distance on a basis of the vehicle speed of the second vehicle (VB) and the first predetermined deceleration degree, and the second notification issuing unit (B119a, B119b) has a second predetermined deceleration degree set in advance as a deceleration degree that is higher than the first predetermined deceleration degree, and calculates the second predetermined distance on a basis of the vehicle speed of the second vehicle (VB) and the second predetermined deceleration degree.

7. The vehicle notification system (1) according to claim 6, further comprising: a deceleration degree learning unit that learns an actual deceleration degree when the second vehicle (VB) decelerates in response to the notification issuance in the second predetermined mode and calculates a learning value that indicates the actual deceleration degree; and a deceleration degree correcting unit that corrects at least one of the first predetermined deceleration degree and the second predetermined deceleration degree on a basis of the learning value calculated by the deceleration degree learning unit.

8. The vehicle notification system (1) according to any one of claims 1 to 7, wherein the direction-change-intention detection unit (B114a, B114b) detects the direction change intention in a case where the direction change intention of the first vehicle (VA) has continued for a predetermined period of time or more.

9. The vehicle notification system (1) according to any one of claims 1 to 8, wherein the notification issuance in the second predetermined mode by the second notification issuing unit (B119a, B119b) is prioritized over the notification issuance in the first predetermined mode by the first notification issuing unit (B118a, B118b).

10. A vehicle notification system (1, 101a) that issues a notification related to other traffic participants including vehicles (VB) other than a host vehicle (VA) that turns right or left at an intersection (CS), the vehicle notification system (1, 101a) comprising: a road map storage unit (B113a) that stores a road map including the intersection (CS); a direction-change-intention detection unit (B114a) that detects a direction change intention of the host vehicle (VA) while turning right or left at the intersection (CS); a host vehicle position specification unit (B111a) that specifies a current position of the host vehicle (VA) on the road map; an other vehicle information acquisition unit (122a) that acquires vehicle information including position information about another vehicle (VB) through communication with another vehicle (VB), when there is another vehicle (VB) traveling in a straight direction toward the intersection (CS) in a lane (L22) opposite to the traveling lane (L11) where the host vehicle (VA) is present; an other vehicle position specification unit (B112a) that specifies a current position of another vehicle (VB) on the road map on a basis of the vehicle information of another vehicle (VB) acquired by the other vehicle information acquisition unit (122a); a first vehicle behavior detection unit (B116a) that detects, on a basis of the current position of the host vehicle (VA) specified by the host vehicle position specification unit (B111a), that the host vehicle (VA) is present at a first predetermined position in the traveling lane (L11) or a position closer to an intersection center (CTR) than the first predetermined position after the direction-change-intention detection unit (B114a) detects the direction change intention, the intersection center (CTR) being a center position of the intersection (CS); a second vehicle behavior detection unit (B117a) that regards, as a predicted collision point (CPP), a point at which a path along which the host vehicle (VA) travels when passing the intersection (CS) and a path along which another vehicle (VB) travels when passing the intersection (CS) intersect and detects that the host vehicle (VA) is traveling at a position closer to the predicted collision point (CPP) than the first predetermined position toward the predicted collision point (CPP) or that the host vehicle (VA) is present at a position closer to the predicted collision point (CPP) than a second predetermined position between the first predetermined position and the predicted collision point; a first notification issuing unit (B118a) that issues a notification in a first predetermined mode under a condition that another vehicle (VB) is located at a first predetermined distance from the intersection (CS) or is present at a location closer to the intersection (CS) than the first predetermined distance in a case where the first vehicle behavior detection unit (B116a) detects that the host vehicle (VA) is present at the first predetermined position or the position that is closer to the intersection center (CTR) than the first predetermined position; and a second notification issuing unit (B119a) that issues a notification in a second predetermined mode that is different from the first predetermined mode under a condition that another vehicle (VB) is located at a second predetermined distance from the intersection (CS) or is present at a position closer to the intersection (CS) than the second predetermined distance in a case where the second vehicle behavior detection unit (B117a) detects that the host vehicle (VA) is traveling at a position closer to the predicted collision point (CPP) than the first predetermined position or that the host vehicle (VA) is present at a position closer to the predicted collision point (CPP) than the second predetermined position, the second predetermined distance being shorter than the first predetermined distance.

11. The vehicle notification system (1, 101a) according to claim 10, further comprising a specific vehicle information transmitting unit (121a) that transmits specific vehicle information to another vehicle (VB), the specific vehicle information indicating implementation of at least one of the notifications by the first notification issuing unit (B118a) and the second notification issuing unit (B119a).

12. A vehicle notification system (1, 101b) that issues a notification related to other traffic participants including vehicles (VA) other than a host vehicle (VB) that travels in a straight direction toward an intersection (CS), the vehicle notification system (1, 101b) comprising: a road map storage unit (B113b) that stores a road map including the intersection (CS); a host vehicle position specification unit (B111b) that specifies a current position of the host vehicle (VB) on the road map; an other vehicle information acquisition unit (122b) that acquires vehicle information including position information about another vehicle (VA) through communication with another vehicle (VA), when there is another vehicle (VA) in a lane (L11) opposite to the lane (L22) where the host vehicle (VB) travels; a direction-change-intention detection unit (B114b) that detects a direction change intention of another vehicle (VA) while turning right or left at the intersection (CS) on a basis of the vehicle information of another vehicle (VA) acquired by the other vehicle information acquisition unit (122b); an other vehicle position specification unit (B112b) that specifies a current position of another vehicle (VA) on the road map based on the vehicle information of another vehicle (VA); a first vehicle behavior detection unit (B116b) that detects, on a basis of the current position of another vehicle (VA) specified by the other vehicle position specification unit (B112b), that another vehicle (VA) is present at a first predetermined position in the opposite lane (L11) or a position closer to an intersection center (CTR) than the first predetermined position after the direction-change-intention detection unit (B114b) detects the direction change intention, the intersection center (CTR) being a center position of the intersection (CS); a second vehicle behavior detection unit (B117b) that regards, as a predicted collision point (CPP), a point at which a path along which the host vehicle (VB) travels when passing the intersection (CS) and a path along which another vehicle (VA) travels when passing the intersection (CS) intersect and detects that another vehicle (VA) is traveling at a position closer to the predicted collision point (CPP) than the first predetermined position toward the predicted collision point (CPP) or that another vehicle (VA) is present at a position closer to the predicted collision point (CPP) than a second predetermined position between the first predetermined position and the predicted collision point (CPP); a first notification issuing unit (B118b) that issues a notification in a first predetermined mode under a condition that the host vehicle (VB) is located at a first predetermined distance from the intersection (CS) or is present at a location closer to the intersection (CS) than the first predetermined distance in a case where the first vehicle behavior detection unit (B116b) detects that another vehicle (VA) is present at the first predetermined position or the position that is closer to the intersection center (CTR) than the first predetermined position; and a second notification issuing unit (B119b) that issues a notification in a second predetermined mode that is different from the first predetermined mode under a condition that the host vehicle (VB) is located at a second predetermined distance from the intersection (CS) or is present at a position closer to the intersection (CS) than the second predetermined distance in a case where the second vehicle behavior detection unit (B117b) detects that another vehicle (VA) is traveling at a position closer to the predicted collision point (CPP) than the first predetermined position or that another vehicle (VA) is present at a position closer to the predicted collision point (CPP) than the second predetermined position, the second predetermined distance being shorter than the first predetermined distance.

13. The vehicle notification system (1, 101b) according to claim 12, further comprising a specific vehicle information transmitting unit (121b) that transmits specific vehicle information to another vehicle (VA), the specific vehicle information indicating implementation of at least one of the notifications by the first notification issuing unit (B118b) and the second notification issuing unit (B119b).

14. A vehicle notification system (1) that issues a notification to traffic participants including a first vehicle (VA) and a second vehicle (VB, VC), the first vehicle (VA) being present in a traveling lane (L11) leading to an intersection (CS) and turning right or left at the intersection (CS), and the second vehicle (VB,VC) traveling toward the intersection (CS) in a lane (L22, L31) leading to the intersection (CS) other than the traveling lane (L11), the vehicle notification system (1) comprising: a road map storage unit (B113a, B113b) that stores a road map including the intersection (CS); 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, VC) on the road map; a direction-change-intention detection unit (B114a, B114b) that detects a direction change intention of the first vehicle (VA) while turning right or left at the intersection (CS); a first issuance timing setting unit (B116a, B116b) that sets a first issuance timing according to a relative position of the first vehicle (VA) with respect to an intersection area (ACS) based on the current position of the first vehicle (VA) specified by the first vehicle position specification unit (B111a, B112b), the intersection area (ACS) overlapping the path along which the first vehicle (VA) travels when passing the intersection (CS) and being set in association with the road map; a second issuance timing setting unit (B117a, B117b) that sets a second issuance timing according to a behavior of the first vehicle (VA) within the intersection area (ACS), after the first issuance timing has been set by the first issuance timing setting unit (B116a, B116b); and a notification issuing unit (B118a, B119a, B118b, B119b) that issues a notification in a predetermined mode to the traffic participants under a condition that issuance conditions defined with respect to a position of the second vehicle (VB, VC) are satisfied at each of the first issuance timing set by the first issuance timing setting unit (B116a, B116b) and the second issuance timing set by the second issuance timing setting unit (B117a, B117b).

15. A vehicle notification system (1) that issues a notification to traffic participants including a first vehicle (VA) and a second vehicle (VB, VC), the first vehicle (VA) being present in a traveling lane (L11) leading to an intersection (CS) and turning right or left at the intersection (CS), and the second vehicle (VB, VC) traveling toward the intersection (CS) in a lane (L22, L31) leading to the intersection (CS) other than the traveling lane (L11), the vehicle notification system (1) comprising: a road map storage unit (B113a, B113b) that stores a road map including the intersection (CS); 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, VC) on the road map; a direction-change-intention detection unit (B114a, B114b) that detects a direction change intention of the first vehicle (VA) while turning right or left at the intersection (CS); a first issuance timing setting unit (B116a, B116b) that sets a first issuance timing when the first vehicle (VA) is present in an intersection area (ACS), the intersection area (ACS) overlapping the path along which the first vehicle (VA) travels when passing the intersection (CS) and being set in association with the road map; a second issuance timing setting unit (B117a, B117b) that sets a second issuance timing when the first vehicle (VA) is in a predicted collision area (ACP), the predicted collision area (ACP) being different from the intersection area (ACS) and including a predicted collision point (CPP) at which a path along which the first vehicle (VA) travels when passing the intersection (CS) and a path along which the second vehicle (VB, VC) travels when passing the intersection (CS) intersect; and a notification issuing unit (B118a, B119a, B118b, B119b) that issues a notification in a predetermined mode to the traffic participants under a condition that issuance conditions defined with respect to a position of the second vehicle (VB, VC) are satisfied at each of the first issuance timing set by the first issuance timing setting unit (B116a, B116b) and the second issuance timing set by the second issuance timing setting unit (B117a, B117b).

16. The vehicle notification system (1) according to claim 14 or 15, wherein the second vehicle (VB, VC) is a straight traveling vehicle (VB) traveling towards the intersection (CS) in a lane (L22) opposite to the traveling lane (L11).

17. The vehicle notification system (1) according to claim 14 or 15, wherein the second vehicle (VB, VC) is a crossing vehicle (VC) traveling towards the intersection (CS) in a lane (L31) intersecting the traveling lane (L11).

Images