Vehicle notification system

Abstract

A vehicle notification system that contributes to further improving traffic safety is provided. [Solution] In a traffic situation where a right-turning vehicle VA and a straight-moving vehicle VB are facing each other across an intersection CS, the vehicle notification system sets the timing of alerting according to the relative position of the right-turning vehicle VA with respect to the intersection CS. Alerting distances Dth1 and Dth2 are calculated based on preset deceleration rates DEC1 and DEC2 as the distance required for the straight-moving vehicle VB to decelerate, and an alert is issued in a predetermined mode if, at the time of the alerting timing, the straight-moving vehicle VB is within the alerting distance DEC1 or DEC2 from the intersection CS or is closer to the intersection CS than this.

Description

[Technical Field]

[0001] The present invention relates to a vehicle notification system. [Background technology]

[0002] There is a technology that aims to assist drivers when turning right at an intersection on a left-hand traffic road by understanding the driving conditions of other traffic participants, including oncoming vehicles traveling straight toward the intersection in the oncoming lane, and instructing the driver on the timing of the right turn to avoid a collision with an oncoming vehicle.

[0003] Here, detection of traffic participants is generally performed by an on-board sensor such as a camera or radar. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-265832 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when using an on-board sensor, it is difficult to detect traffic participants in blind spots, such as behind an obstacle.

[0006] Specifically, if there is another vehicle traveling alongside the oncoming vehicle in the same lane, or if another vehicle is stopped in front of the oncoming vehicle waiting to turn right, the other vehicle becomes an obstacle and is in the blind spot of the other vehicle, making it difficult for the onboard sensors installed in the right-turning vehicle to detect the oncoming vehicle.

[0007] If the other vehicle acting as an obstacle is a large vehicle, the blind spot will be wider, making it more difficult to detect the oncoming vehicle.

[0008] Therefore, an object of the present invention is to provide a vehicle notification system that contributes to further improving traffic safety. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems, one aspect of the present invention provides a vehicle notification system that issues an alert to traffic participants, including a right-turning vehicle in a lane leading to an intersection and a straight-moving vehicle traveling straight toward the intersection in an oncoming lane to the lane in which the right-turning vehicle is located, the system comprising: an alert timing setting means for setting an alert timing according to a relative position of the right-turning vehicle with respect to the intersection; and an alert issuing means for issuing an alert in a predetermined mode to the traffic participants, on the condition that an alert condition determined with respect to the position of the straight-moving vehicle is satisfied at the alert timing set by the alert timing setting means. The alert issuing means calculates an alert distance based on a predetermined deceleration as a distance required to decelerate the straight-moving vehicle, and issues the alert in the predetermined mode if the straight-moving vehicle is located within the alert distance from the intersection or closer to the intersection at the alert timing. [Effects of the Invention]

[0010] According to one aspect of the present invention, in a situation where a right-turning vehicle and a straight-moving vehicle are facing each other across an intersection, the timing of issuing an alert is set according to the relative position of the right-turning vehicle with respect to the intersection. Here, an alert distance is calculated based on a preset deceleration, and if the straight-moving vehicle is at or closer to the intersection than this alert distance at the time of the alert, an alert is issued in a predetermined mode. This makes it possible to issue an alert at a timing that matches the driver's sensation (driving feeling) when the straight-moving vehicle decelerates in response to the alert, thereby preventing the driver from feeling uneasy due to a mismatch between the driver's sensation and the timing of the alert, and enabling more appropriate alert issuing. [Brief explanation of the drawings]

[0011] [Figure 1]1 is a schematic diagram showing an overall configuration of a vehicle notification system according to an embodiment of the present invention; [Figure 2] FIG. 2 is a schematic diagram showing the internal configuration of a controller provided in a right-turning vehicle. [Figure 3] FIG. 2 is a schematic diagram showing the internal configuration of a controller provided in a straight-moving vehicle. [Figure 4] 10 is a flowchart showing the overall flow of notification control. [Figure 5] 10 is a flowchart showing the contents of an information presentation process. [Figure 6] 10 is a flowchart showing the contents of an information presentation distance calculation process. [Figure 7] 10 is a flowchart showing the contents of a warning process. [Figure 8] 10 is a flowchart showing the contents of a warning distance calculation process. [Figure 9] FIG. 10 is an explanatory diagram showing a method for calculating an information presentation distance and a warning distance (based on the speed of a straight-moving vehicle). [Figure 10] 10 is an explanatory diagram showing a method of calculating an information presentation distance and a warning distance (based on the relative vehicle speed of a straight-moving vehicle). FIG. [Figure 11] 10 is an explanatory diagram showing changes in decelerations DEC1 and DEC2 according to the vehicle speed or relative vehicle speed of a vehicle turning right. FIG. [Figure 12] FIG. 2 is a schematic diagram showing an example of a traffic situation that is expected to be the subject of notification. [Figure 13] FIG. 10 is a schematic diagram showing the relationship between a right-turning vehicle and a straight-moving vehicle at the timing of issuing an information notification (when the right-turning vehicle is traveling at a low speed). [Figure 14] FIG. 10 is a schematic diagram showing the relationship between a right-turning vehicle and a straight-moving vehicle at the timing of issuing an alarm (when the right-turning vehicle is traveling at a low speed). [Figure 15] 10 is a schematic diagram showing the relationship between a right-turning vehicle and a straight-moving vehicle at the timing of issuing an information notification (when the right-turning vehicle is traveling at a high speed). FIG. [Figure 16] FIG. 10 is a schematic diagram showing the relationship between a right-turning vehicle and a straight-moving vehicle at the timing of issuing an alarm (when the right-turning vehicle is traveling at a high speed). [Figure 17]FIG. 2 is a schematic diagram showing the situation after a straight-moving vehicle has passed through an intersection. DETAILED DESCRIPTION OF THE INVENTION

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0013] (Overall configuration of vehicle notification system) FIG. 1 is a schematic diagram showing the configuration of a vehicle notification system (hereinafter, sometimes simply referred to as "notification system") 1 according to one embodiment of the present invention.

[0014] In this embodiment, a traffic situation is assumed in which 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-moving vehicle") VB traveling straight toward the intersection in a lane (hereinafter referred to as an "oncoming lane") opposite the lane in which the right-turning vehicle VA is traveling (hereinafter referred to as a "driving lane"). The notification system 1 is applicable not only to left-hand traffic roads but also to right-hand traffic roads. In the case of right-hand traffic, the notification system 1 targets a traffic situation in which a left-turning vehicle traveling toward an intersection and a straight-moving vehicle traveling in an oncoming lane toward the intersection exist. In other words, the notification system 1 is applicable to traffic situations in which right-turning or left-turning vehicles (hereinafter referred to as "right / left-turning vehicles" or "non-straight-moving vehicles") in the driving lane and straight-moving vehicles in the oncoming lane coexist. In the case of left-hand traffic, the right-turning vehicle is a vehicle turning right at the intersection and must not obstruct the straight-moving vehicle traveling in the oncoming lane from passing through the intersection.

[0015] The notification system 1 includes a controller 101 as main elements related to this embodiment, as well as accessory devices such as vehicle sensors 111 to 113, communication devices 121 and 122, and an HMI (human machine interface) device 131.

[0016] In this embodiment, these various elements including the controller 101 are provided in each of the right-turning vehicle VA and the straight-moving vehicle VB. The controller 101a provided in the right-turning vehicle VA and the controller 101b provided in the straight-moving vehicle VB cooperate with each other to form a single virtual controller that constitutes the notification system 1. Naturally, the notification system 1 can be configured as an in-vehicle system for the right-turning vehicle VA using the controller 101a provided in the right-turning vehicle VA and its associated devices, and can also be configured as an in-vehicle system for the straight-moving vehicle VB using the controller 101b provided in the straight-moving vehicle VB and its associated devices.

[0017] In the following description, vehicle-to-vehicle communication is performed between a right-turning vehicle VA and a straight-moving vehicle VB, and vehicle information regarding the right-turning vehicle VA can be shared between the right-turning vehicle VA and the straight-moving vehicle VB, and vehicle information regarding the straight-moving vehicle VB can be shared between these vehicles VA and VB. In this embodiment, the vehicle information to be communicated or shared between the right-turning vehicle VA and the straight-moving vehicle VB includes the current positions Pa, Pb, vehicle speeds VSPa, VSPb, right turn signal operation status (i.e., right turn signal switch output), and lane ID of each vehicle VA and VB. Communication between the right-turning vehicle VA and the straight-moving vehicle VB is not limited to direct communication via vehicle-to-vehicle communication, but can also be indirectly performed via a roadside device installed on the side of the road, a server located in a remote location, or a communication device provided in a vehicle other than the right-turning vehicle VA and the straight-moving vehicle VB.

[0018] In this embodiment, the right-turning vehicle VA and the straight-moving vehicle VB have the same basic configuration to constitute the notification system 1. The right-turning vehicle VA includes a controller 101a, vehicle sensors 111a, 112a, and 113a, communication devices 121a and 122a, and an HMI device 131a. On the other hand, the straight-moving vehicle VB includes a controller 101b, vehicle sensors 111b, 112b, and 113b, communication devices 121b and 122b, and an HMI device 131b.

[0019] The controllers 101a and 101b constitute the calculation unit of the notification system 1, and generate and output command signals according to the calculation results. The controllers 101a and 101b are constituted by a microcomputer equipped with a central processing unit (CPU), storage devices such as ROM and RAM, and an input / output interface.

[0020] The vehicle sensors 111a to 113b and 111b to 113b constitute the detection unit of the notification system 1. The right-turning vehicle VA is equipped with, as its accompanying vehicle sensors, a position sensor 111a, a vehicle speed sensor 112a, and a right blinker switch 113a, and the straight-moving vehicle VB is equipped with, as its accompanying vehicle sensors, a position sensor 111b, a vehicle speed sensor 112b, and a right blinker switch 113b.

[0021] 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-moving vehicle VB. The position sensors 111a and 111b can each be configured with a receiver for a Global Navigation Satellite System (GNSS), and detect the current positions of the target vehicles VA and VB using latitude and longitude coordinates Pa (Pai, ​​Paj) and Pb (Pbi, Pbj).

[0022] Vehicle speed sensor 112a detects the traveling speed (hereinafter referred to as "vehicle speed") VSPa of right-turning vehicle VA, and vehicle speed sensor 112b detects the vehicle speed VSPb of straight-moving vehicle VB. Vehicle speed sensors 112a and 112b can detect the wheel speeds (e.g., rotational speeds of driven wheels) of target vehicles VA and VB and convert them into traveling distance per unit time using tire dynamic radius or the like.

[0023] The right blinker switch 113a outputs an ON signal when the right turn indicator (hereinafter referred to as "right blinker") of the right-turning vehicle VA is activated, and the right blinker switch 113b outputs an ON signal when the right blinker of the straight-moving vehicle VB is activated. The activation of the right blinker switches 113a and 113b indicates that the target vehicles VA and VB intend to turn right or change lanes.

[0024] Detection signals from the position sensor 111a, the vehicle speed sensor 112a and the right blinker switch 113a are output to the controller 101a, and detection signals from the position sensor 111b, the vehicle speed sensor 112b and the right blinker switch 113b are output to the controller 101b.

[0025] The HMI devices 131a and 131b constitute the output section of the notification system 1. The HMI device 131a receives a command signal from the controller 101a and notifies the driver of the right-turning vehicle VA about the traffic conditions. The HMI device 131b receives a command signal from the controller 101b and notifies the driver of the straight-moving vehicle VB about the traffic conditions.

[0026] The notification by the HMI devices 131a and 131b may be visual or audible. The HMI devices 131a and 131b can provide notification by both display and sound, or can provide notification by either one of these. The HMI devices 131a and 131b are placed in a location that is easily visible to the driver, such as on the dashboard inside the vehicle.

[0027] In addition to the above, the right-turning vehicle VA is equipped with a transmitter 121a and a receiver 122a, and the straight-moving vehicle VB is equipped with a transmitter 121b and a receiver 122b. The transmitter 121a and the receiver 122a equipped in the right-turning vehicle VA constitute an inter-vehicle communication device for the right-turning vehicle VA, and the transmitter 121b and the receiver 122b equipped in the straight-moving vehicle VB constitute an inter-vehicle communication device for the straight-moving vehicle VB. The right-turning vehicle VA and the straight-moving vehicle VB can communicate wirelessly via each other's inter-vehicle communication devices.

[0028] As mentioned above, communication between the right-turning vehicle VA and the straight-moving vehicle VB is not limited to direct communication between the right-turning vehicle VA and the straight-moving vehicle VB, but may also be indirect communication via a roadside device, a remote server, or another vehicle.

[0029] FIG. 12 is a schematic diagram showing an example of a traffic situation that is expected to be the subject of notification according to this embodiment.

[0030] In this embodiment, a traffic situation is assumed in which a right-turning vehicle VA and a straight-moving vehicle VB are facing each other across an intersection CS. An intersection (in this embodiment, a crossroads) CS exists on a two-lane road R that includes right-turn lanes L11 and L21 and straight-moving lanes L12 and L22. The right-turning vehicle VA is in one right-turn lane L11 and is approaching the intersection CS, while the straight-moving vehicle VB is in the other straight-moving lane L22 and is traveling straight toward the intersection CS at a position away from the intersection CS. Here, the right-turn lane L11 corresponds to the lane in which the right-turning vehicle VA is traveling, and the right-turn lane L21 and the straight-moving lane L22 correspond to oncoming lanes relative to the right-turning vehicle VA. The oncoming right-turn lane L21 and the straight-moving lane L22 may hereinafter be referred to as the "oncoming right-turn lane" and the "oncoming straight-moving lanes."

[0031] In addition to the right-turning vehicle VA and the straight-moving vehicle VB, in the oncoming right-turn lane L21, there is a vehicle (hereinafter referred to as the "waiting vehicle") VC stopped in front of the stop line SL2 ahead of the straight-moving vehicle VB, waiting to turn right. In the traffic situation shown in the figure, the waiting vehicle VC is a visual obstacle that blocks part of the view from the right-turning vehicle VA and also blocks part of the view from the straight-moving vehicle VB. Because the straight-moving vehicle VB is in the blind spot of the waiting vehicle VC from the perspective of the right-turning vehicle VA, it is difficult for the right-turning vehicle VA to see the straight-moving vehicle VB, and because the right-turning vehicle VA is in the blind spot of the waiting vehicle VC from the perspective of the straight-moving vehicle VB, it is difficult for the straight-moving vehicle VB to see the right-turning vehicle VA.

[0032] In such a situation, the notification system 1 monitors the relative positional relationship between the right-turning vehicle VA and the straight-moving vehicle VB after the right-turning vehicle VA indicates its intention to turn right at the intersection CS (hereinafter simply referred to as "intention to turn right"). Then, at an appropriate timing between the time the right-turning vehicle VA approaches the intersection CS and the time it passes through the intersection CS, the notification system 1 issues a notification according to the urgency of the situation regarding contact or collision between the right-turning vehicle VA and the straight-moving vehicle VB.

[0033] (Internal structure of the controller) Fig. 2 is a schematic diagram showing the internal configuration of a controller 101a provided in a right-turning vehicle VA, and Fig. 3 is a schematic diagram showing the internal configuration of a controller 101b provided in a straight-moving vehicle VB. The internal configurations of the controllers 101a and 101b will be described in order using Fig. 2 and Fig. 3, with appropriate reference to Fig. 12 given above.

[0034] 2, the controller 101a includes a host vehicle position detection unit B111a, another 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 alarm generation unit B118a, and a second alarm generation unit B119a. The functions of these units B111a to B119a are realized in software by a central processing unit included in the controller 101a reading a computer program stored in a storage device and operating in accordance with instructions from the program.

[0035] The host vehicle position detection unit B111a detects the current position Pa of the host vehicle, which is the right-turning vehicle VA. The host vehicle position detection unit B111a detects the current position Pa of the host vehicle based on an output signal from a position sensor 111a provided in the right-turning vehicle VA.

[0036] The other vehicle position detection unit B112a detects the current position Pb of the other vehicle, the straight-moving vehicle VB. The other vehicle position detection unit B112a detects the current position Pb of the other vehicle by reading position information indicating the current position Pb from the vehicle information acquired from the straight-moving vehicle VB via the receiver 122a provided in the right-turning vehicle VA.

[0037] The road map storage unit B113a stores a road map. In this embodiment, the current positions Pa, Pb of the right-turning vehicle VA and the straight-going vehicle VB are represented by latitude and longitude coordinates indicating these positions Pa, Pb. The road map storage unit B113a extracts a map of an area or section including the intersection CS from the road map and identifies the current positions Pa, Pb of the right-turning vehicle VA and the straight-going vehicle VB on the road map. Identifiers (hereinafter referred to as "link IDs") corresponding to each lane leading to the intersection CS, such as right-turn lanes L11, L21 and straight-going lanes L12, L22, are assigned to the road map and stored corresponding to each lane L11, L21, L12, and L22. By identifying the position on the road map, it is possible to determine the lane in which the target vehicle exists or is traveling.

[0038] The right-turn intention detection unit B114a detects that the right-turning vehicle VA has an intention to turn right. The right-turn intention detection unit B114a can detect the intention to turn right by an output signal from a right blinker switch 113a provided on the right-turning vehicle VA, or, if the right-turn lane L11 is a right-turn-only lane, by reading out the link ID associated with the current lane from the road map and detecting that the right-turning vehicle VA is in the right-turn lane L11.

[0039] The vehicle speed detection unit B115a detects the vehicle speed VSPb of the straight-moving vehicle VB. The vehicle speed detection unit B115a detects the vehicle speed VSPb of the straight-moving vehicle VB (i.e., the other vehicle) by reading vehicle speed information indicating the vehicle speed VSPb from the vehicle information acquired from the straight-moving vehicle VB via the receiver 122a provided in the right-turning vehicle VA.

[0040] Based on the current position Pa of the right-turning vehicle VA on the road map, the first vehicle behavior detection unit B116a detects that the right-turning vehicle VA is located at a first predetermined position P1 in the lane in which it is traveling (i.e., the right-turning lane L11) or at a position closer to the center position CTR of the intersection CS (hereinafter referred to as the "intersection center") after the right-turn intention detection unit B114a detects an intention to turn right, in other words, after the right-turning vehicle VA indicates an intention to turn right by entering the right-turn lane L11 or activating its right turn signal.

[0041] Fig. 13 is a schematic diagram showing the positional relationship between right-turning vehicle VA and straight-going vehicle VB at the time when right-turning vehicle VA crosses stop line SL1 in right-turn lane L11 and enters intersection CS. Fig. 13 simplifies the illustration of road R, showing only right-turn lane L11 and straight-going lane L22 of two-lane road R (the same applies to Figs. 14 to 17 shown later).

[0042] In this embodiment, an intersection area ACS is set as a criterion for determining the relative positional relationship between a right-turning vehicle VA and an intersection CS. The intersection area ACS is set so as to overlap with the route TRa along which the right-turning vehicle VA travels when passing through the intersection CS. When the right-turning vehicle VA indicates its intention to turn right and reaches or enters the intersection area ACS, it is detected that the right-turning vehicle VA is located at a first predetermined position P1 in the right-turn lane L11 or closer to the intersection center CTR. The first vehicle behavior detection unit B116a sets the timing at which it detects that the right-turning vehicle VA has reached or entered the intersection area ACS as the first alert timing. The first alert timing set by the first vehicle behavior detection unit B116a is the timing at which an alert in a first predetermined mode is issued for the right-turning vehicle VA. The intersection area ACS is set as a circular area concentric with the intersection center CTR and including the first predetermined position P1 on its outer edge. Figures 13 to 17 show the intersection area ACS with a two-dot chain line, the driving route TRa of the right-turning vehicle VA with a dotted chain line, and the collision prediction area ACP and the driving route TRb of the straight-moving vehicle VB, which will be described below, with dashed lines and dotted chain lines, respectively.

[0043] The second vehicle behavior detection unit B117a determines the point where the route TRa that the right-turning vehicle VA takes when passing through the intersection CS and the route TRb that the straight-moving vehicle VB takes when passing through the intersection CS intersect as a ``collision prediction point'' CPP, and detects, based on the current position Pa of the right-turning vehicle VA on the road map, that the right-turning vehicle VA is traveling toward the collision prediction point CPP at a position closer to the collision prediction point CPP than a first predetermined position P1, or that the right-turning vehicle VA is located at a position closer to the collision prediction point CPP than a second predetermined position P2 between the first predetermined position P1 and the collision prediction point CPP.

[0044] FIG. 14 is a schematic diagram showing the positional relationship between a right-turning vehicle VA and a straight-moving vehicle VB when the right-turning vehicle VA enters the intersection CS, moves forward within the intersection CS, and approaches the intersection center CTR.

[0045] In this embodiment, a collision prediction area ACP is set as an area different from the intersection area ACS, with the collision prediction point CPP at its center. After entering the intersection area ACS, a right-turning vehicle VA is traveling within the intersection area ACS toward the collision prediction point CPP or is present within the collision prediction area ACP. This detects that the right-turning vehicle VA is traveling closer to the collision prediction point CPP than the first predetermined position P1 or is present closer to the collision prediction point CPP than the second predetermined position P2. The second vehicle behavior detection unit B117a sets the timing at which the right-turning vehicle VA is traveling within the intersection area ACS toward the collision prediction point CPP or is present within the collision prediction area ACP as the second alert timing. The second alert timing set by the second vehicle behavior detection unit B117a is the timing at which the right-turning vehicle VA issues an alert in a second predetermined mode. The collision prediction 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.

[0046] The intersection area ACS is not limited to a circle, but may be a shape that resembles the area where two intersecting roads overlap (for example, a rectangle with four corners at the corners), or may be the shape of the area surrounded by the stop lines SL1 and SL2 installed on each of the intersecting roads.The same is true for the collision prediction area ACP, which can be set to a shape other than a circle, such as a rectangle (for example, a rectangle with two sides parallel to the road boundary line that defines the oncoming straight-ahead lane L22).

[0047] The first alarm issuing unit B118a outputs a command signal to the HMI device 131a provided in the host vehicle (i.e., the right-turning vehicle VA) to issue an alert in a first predetermined mode, on the condition that a first predetermined alarm issuing condition is met regarding the position Pb of the other vehicle, which is the straight-moving vehicle VB, at the timing when the first alarm issuing unit B118a detects that the right-turning vehicle VA is at a first predetermined position P1 in the right-turn lane L11 or at a position closer to the intersection center CTR than that, that is, at the first alarm issuing timing. In this embodiment, the output of the command signal from the first alarm issuing unit B118a to the HMI device 131a is regarded as "execution of alert in the first predetermined mode."

[0048] The first predetermined alarm condition is that the straight-moving vehicle VB is at a relatively long first predetermined distance (hereinafter referred to as the "information presentation distance") Dth1 from the intersection CS or at a position closer to the intersection CS than this. In this embodiment, the distance Db from the intersection CS to the straight-moving vehicle VB is taken as the distance from the outer edge of the collision prediction area ACP, specifically, the distance from the intersection of the travel path TRb of the straight-moving vehicle VB and a circle (indicated by a dashed line in the figures) that defines the outer edge of the collision prediction area ACP, as shown in Figures 13 and 14.

[0049] The HMI device 131a, which has received the command signal from the first alarm issuing unit B118a, issues an alarm by display and sound to prompt the driver of the right-turning vehicle VA to recognize the presence of the straight-moving vehicle VB traveling in the oncoming straight-moving lane L22 toward the intersection CS. The alarm issued by the first alarm issuing unit B118a is an alarm to present information regarding a relatively low urgency regarding a collision between the right-turning vehicle VA and the straight-moving vehicle VB.

[0050] The second alarm issuing unit B119a outputs a command signal to the HMI device 131a to issue an alert in the second predetermined mode, on the condition that a second predetermined alarm condition determined in advance for the position Pb of the straight-moving vehicle VB is satisfied, when the second alarm issuing unit B119a detects that the right-turning vehicle VA is traveling at a position closer to the predicted collision point CPP than the first predetermined position P1 or is present at a position closer to the predicted collision point CPP than the second predetermined position P2, that is, at the second alarm issuing timing. In this embodiment, the output of the command signal from the second alarm issuing unit B119a to the HMI device 131a is regarded as "issuing an alert in the second predetermined mode."

[0051] The second predetermined alarm condition is that the straight-moving vehicle VB is at a second predetermined distance (hereinafter referred to as the "alarm distance") Dth2 from the intersection CS that is shorter than the information presentation distance Dth1, or is located closer to the intersection CS than this.

[0052] The second predetermined mode is a different mode from the first predetermined mode, and the HMI device 131a, having received a command signal from the second alarm unit B119a, issues an alarm by display and sound to the driver of the right-turning vehicle VA to encourage the driver to recognize a higher level of urgency regarding a collision between the right-turning vehicle VA and the straight-moving vehicle VB. The alarm issued by the second alarm unit B119a is more noticeable and appeals more to the driver's sight or hearing than the alarm issued by the first alarm unit B118a.

[0053] In addition to outputting a command signal to the HMI device 131a, the first alarm unit B118a and the second alarm unit B119a can also notify the straight-moving vehicle VB via the transmitter 121a that an alarm has been issued in each mode, and prompt the vehicle VB to issue an appropriate alarm in accordance with the urgency of the collision with its own vehicle (i.e., the right-turning vehicle VA).

[0054] In this embodiment, the controller 101a provided in the right-turning vehicle VA and the controller 101b provided in the straight-moving vehicle VB basically have the same configuration and have corresponding elements.

[0055] 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 alarm generation unit B118b, and a second alarm generation unit B119b. The internal configuration of the controller 101b will be described below, focusing on the differences from the controller 101a.

[0056] The host vehicle position detection unit B111b detects the current position Pb of the host vehicle, i.e., the straight-moving vehicle VB, and this detection is based on an output signal from a position sensor 111b provided in the straight-moving vehicle VB.

[0057] The other vehicle position detection unit B112b detects the current position Pa of the other vehicle, the right-turning vehicle VA, by reading position information indicating the current position Pa from the vehicle information obtained from the right-turning vehicle VA via the receiver 122b provided in the straight-moving vehicle VB.

[0058] Similar to the road map storage unit B113a, the road map storage unit B113b stores a road map that includes an intersection CS and to which link IDs of the lanes leading to the intersection CS are assigned, and identifies the current positions Pb and Pa of the straight-moving vehicle VB and the right-turning vehicle VA on the road map. The road maps stored in the road map storage units B113b and B113a may have different accuracy, but in this embodiment, both road maps have an accuracy that is compatible with satellite positioning using GNSS.

[0059] The right-turn intention detection unit B114b detects the right-turning vehicle VA's intention to turn right by identifying the link ID of the lane in which the right-turning vehicle VA is located from the current position Pa of the right-turning vehicle VA, or by reading information indicating the operation status of the right blinker from the 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 in which each vehicle VA and VB are located in the vehicle information exchanged between the straight-moving vehicle VB and the right-turning vehicle VA, and to detect the right-turning vehicle VA's intention to turn right based on the link ID acquired through communication.

[0060] The vehicle speed detection unit B115b detects the vehicle speed VSPa of the right-turning vehicle VA by reading vehicle speed information indicating the vehicle speed VSPa from the vehicle information obtained from the right-turning vehicle VA via the receiver 122b provided in the straight-moving vehicle VB.

[0061] After the right-turning vehicle VA indicates its intention to turn right, the first vehicle behavior detection unit B116b detects that the vehicle is at a predetermined relative position relative to the intersection CS, with the first predetermined position P1 as the reference. Specifically, as described above, 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 or entered the intersection area ACS. The first vehicle behavior detection unit B116b then sets the detection timing as the first alert timing. The first alert timing set by the first vehicle behavior detection unit B116b is the timing at which an alert in the first predetermined mode is issued for the straight-moving vehicle VB.

[0062] The size and shape of the intersection area ACS may be the same or different between the controller 101a and the controller 101b. For example, it is possible to variably set the size of the intersection area ACS or change its shape depending on the driver's choice or the tendency of the driving state when passing through the intersection CS.

[0063] The second vehicle behavior detection unit B117b monitors the behavior of the right-turning vehicle VA after entering the intersection CS, and detects that the right-turning vehicle VA is traveling within the intersection area ACS toward the predicted collision point CPP or is present within the predicted collision area ACP after entering the intersection area ACS. The second vehicle behavior detection unit B117b then sets the detection timing as the second alert timing. The second alert timing set by the second vehicle behavior detection unit B117b is the timing at which an alert in the second predetermined mode is issued for the straight-moving vehicle VB.

[0064] The size and shape of the predicted collision area ACP may be different between the controller 101a and the controller 101b, but in this embodiment, they are set to the same size and shape. The predicted collision area ACP may be set in advance as predetermined coordinates on a road map, or may be set by notifying the other controller of the coordinate information of the predicted collision area ACP set in one of the controllers 101a, 101b via vehicle-to-vehicle communication or the like.

[0065] When the first alarm unit B118b detects that the right-turning vehicle VA has arrived at or entered the intersection area ACS, that is, at the first alarm timing, the first alarm unit B118b outputs a command signal to the HMI device 131b provided in the host vehicle (i.e., the straight-moving vehicle VB) to issue an alarm in a first predetermined mode, provided that a first predetermined alarm condition related to the position Pb of the straight-moving vehicle VB is met. As described above, the first predetermined alarm condition is that the straight-moving vehicle VB is located at an information presentation distance Dth1 from the intersection CS or closer to the intersection CS. The output of the command signal from the first alarm unit B118b to the HMI device 131b is deemed to be "the implementation of an alarm in the first predetermined mode."

[0066] The HMI device 131b, which has received the command signal from the first alarm issuing unit B118b, issues an alarm by display and sound to the driver of the straight-moving vehicle VB to prompt the driver to be aware that there is a right-turning vehicle VA that should be watched out for in the oncoming right-turn lane L11. As described above, the alarm issued by the first alarm issuing unit B118b is an alarm to present information regarding a relatively low urgency regarding a collision between the straight-moving vehicle VB and the right-turning vehicle VA.

[0067] The second alarm unit B119b outputs a command signal to the HMI device 131b to issue an alarm in a second predetermined mode when it detects that the right-turning vehicle VA is traveling within the intersection area ACS toward the predicted collision point CPP or is present within the predicted collision area ACP, that is, at the second alarm timing, provided that a second predetermined alarm condition related to the position Pb of the straight-moving vehicle VB is met. The second predetermined alarm condition is that the straight-moving vehicle VB is at a warning distance Dth2 from the intersection CS or is present at a position closer to the intersection CS than this. The output of the command signal from the second alarm unit B119b to the HMI device 131b is deemed to be "the implementation of an alarm in the second predetermined mode."

[0068] The HMI device 131b, which has received the command signal from the second alarm issuing unit B119b, issues a visual and audio alert to the driver of the straight-moving vehicle VB to encourage greater awareness of the urgency of the collision between the straight-moving vehicle VB and the right-turning vehicle VA. The alert issued by the second alarm issuing unit B119b is similar to that described above, and is an alert that is more noticeable and appeals more to the driver's visual or auditory senses.

[0069] In addition to outputting a command signal to the HMI device 131b, the first alarm issuing unit B118b and the second alarm issuing unit B119b can also notify the right-turning vehicle VA via the transmitter 121b that an alarm has been issued in each mode.

[0070] 9 and 10 are explanatory diagrams showing a method for calculating the information presentation distance Dth1 and the warning distance Dth2.

[0071] In this embodiment, the information presentation distance Dth1 and the warning distance Dth2 each correspond to an "alarm distance", with the information presentation distance Dth1 corresponding to a "first alarm distance" and the warning distance Dth2 corresponding to a "second alarm distance".

[0072] The first alarm unit B118a of the controller 101a and the first alarm unit B118b of the controller 101b read the vehicle speeds VSPa and VSPb of the right-turning vehicle VA and the straight-moving vehicle VB, respectively, when calculating the information presentation distance Dth1. The second alarm unit B119a of the controller 101a and the second alarm unit B119b of the controller 101b read the vehicle speeds VSPa and VSPb of the right-turning vehicle VA and the straight-moving vehicle VB, respectively, when calculating the warning distance Dth2.

[0073] The vehicle speeds VSPa and VSPb of each vehicle VA and VB used to calculate the alarm distance, i.e., the information presentation distance Dth1 which is the first alarm distance and the warning distance Dth2 which is the second alarm distance, are the vehicle speeds at the first and second alarm timings, respectively, but for simplicity, it is also possible to use the vehicle speed at the first alarm timing for each of the vehicle speeds VSPa and VSPb.

[0074] In this embodiment, the vehicle speed of the straight-moving vehicle VSPb used to calculate the alarm distance is switched between the absolute vehicle speed VSPb (hereinafter, when simply referring to "vehicle speed," it will refer to the absolute vehicle speed) and the relative vehicle speed RSPb, depending on the vehicle speed VSPa of the right-turning vehicle VA. Here, the relative vehicle speed RSPb is the vehicle speed (=VSPa+VSPb) of the straight-moving vehicle VB relative to the right-turning vehicle VA.

[0075] Specifically, when the vehicle speed VSPa of the right-turning vehicle VA is higher than a predetermined vehicle speed Vth1, the relative vehicle speed RSPb of the straight-moving vehicle VB is used to calculate the alarm distances Dth1 and Dth2. When the vehicle speed VSPa is equal to or lower than the predetermined vehicle speed Vth1, the vehicle speed VSPb of the straight-moving vehicle VB is used. In this embodiment, the predetermined vehicle speed Vth1 is a vehicle speed that is expected to substantially increase the driver's sense of the approach of the other vehicle, in other words, the sense that the distance between the vehicle and the other vehicle is shortening. The predetermined vehicle speed Vth1 can be appropriately selected and set by a sensory evaluation test or the like. The predetermined vehicle speed Vth1 is, for example, 20 km / h.

[0076] When the vehicle speed VSPa of the right-turning vehicle VA is equal to or less than a predetermined vehicle speed Vth1, the information presentation distance Dth1 and the warning distance Dth2 are calculated based on the vehicle speed VSPb of the straight-moving vehicle VB and the deceleration rates DEC1 and DEC2 that are preset according to the alarm mode, as the distance that the straight-moving vehicle VB is expected to travel from its current vehicle speed VSPb to a stop after the alarm is issued, in other words, the distance required for the straight-moving vehicle VB to stop.

[0077] As shown in FIG. 9, the information presentation distance Dth1 is calculated by adding the estimated travel distance to each of the free-running time PRD1 and the deceleration time PRD2 based on the vehicle speed VSPb (=V1) of the straight-moving vehicle VB at the first alert timing. The free-running time PRD1 is the sum of the reaction time required for the driver to recognize, judge, and operate the vehicle after the alert is issued until the driver actually applies the brakes, and the operational delay time of the system and hydraulic equipment in response to the brake operation. In this embodiment, the free-running time PRD1 is preset to a fixed time (=ΔT). The deceleration time PRD2 is the time required from when the brakes actually begin to apply until the vehicle stops, and can be calculated based on the vehicle speed VSPb and the deceleration DEC1 (PRD2=VSPb / DEC1). Specifically, the information presentation distance Dth1 is calculated using the following equation (1.1): Dth1=VSPb×ΔT+VSPb×(VSPb / DEC1) / 2 …(1.1)

[0078] Similarly, the warning distance Dth2 is calculated by adding the estimated distance to each of the free-running time PRD1 and the deceleration time PRD2, but a different deceleration DEC2 is used than the one used to calculate the information presentation distance Dth1. The deceleration DEC2 used to calculate the warning distance is higher than the deceleration DEC1 used to calculate the information presentation distance, in other words, a deceleration with a larger absolute value than the deceleration DEC1 (|DEC1|<|DEC2|). Specifically, this is calculated using the following equation (2.1): Dth2=VSPb×ΔT+VSPb×(VSPb / DEC2) / 2 …(2.1)

[0079] In contrast, when the vehicle speed VSPa of the right-turning vehicle VA is higher than a predetermined vehicle speed Vth1, the information presentation distance Dth1 and the warning distance Dth2 are calculated based on the relative vehicle speed RSPb of the straight-moving vehicle VB and the decelerations DEC1 and DEC2 preset according to the alarm mode, as the distance the straight-moving vehicle VB is expected to travel before stopping after the alarm is activated, assuming the relative vehicle speed RSPb is the vehicle speed. In this embodiment, the decelerations DEC1 and DEC2 used to calculate the alarm distance are the same whether the vehicle speed VSPa of the right-turning vehicle VA is higher than the predetermined vehicle speed Vth1 or lower. Possible decelerations DEC1 and DEC2 are, for example, DEC1 = -0.1G and DEC2 = -0.2G.

[0080] As shown in Fig. 10, the information presentation distance Dth1 is calculated by adding the distance expected to be traveled to each of the free-running time PRD1 and the deceleration time PRD2 based on the relative vehicle speed RSPb (=V2) of the straight-moving vehicle VB at the first alert timing. The free-running time PRD1 is set in advance as a fixed time (=ΔT), and the deceleration time PRD2 can be calculated based on the relative vehicle speed RSPb and the deceleration DEC1 (PRD2=RSPb / DEC1). Specifically, the information presentation distance Dth1 is calculated using the following equation (1.2): Dth1=RSPb×ΔT+RSPb×(RSPb / DEC1) / 2 …(1.2)

[0081] Similarly, the warning distance Dth2 is calculated by adding the distance that is expected to be traveled during the free-running time PRD1 and the deceleration time PRD2 based on the relative vehicle speed RSPb and deceleration DEC2 of the straight-moving vehicle VB. Specifically, this is calculated using the following equation (2.2): Dth2=RSPb×ΔT+RSPb×(RSPb / DEC2) / 2 …(2.2)

[0082] The information presentation distance Dth1 and the warning distance Dth2 may be set to the same distance or different distances between the controllers 101a and 101b. When setting different distances, for example, at least one of the decelerations DEC1 and DEC2 is made different between the right-turning vehicle VA and the straight-moving vehicle VB. For example, since it is considered that the driver of the straight-moving vehicle VB feels a stronger sense of an approaching vehicle than the driver of the right-turning vehicle VA, at least one of the decelerations DEC1 and DEC2 of the controller 101b is set to a value greater than the decelerations DEC1 and DEC2 of the controller 101a.

[0083] (Contents of notification control for right-turning vehicles) 4 to 8 are flowcharts showing the details of notification control executed by the controller 101a provided in the right-turning vehicle VA. The flowchart in FIG. 4 shows the overall flow of the notification control, the flowcharts in FIGS. 5 and 6 show the details of the process (information presentation process) performed by the right-turning vehicle VA regarding information presentation, and the flowcharts in FIGS. 7 and 8 show the details of the process (alarm process) performed by the right-turning vehicle VA regarding an alarm. The information presentation process and the alarm process are executed as part of the notification control. When the controller 101a detects an intersection on the road ahead of its own vehicle (i.e., the right-turning vehicle VA), it executes the notification control at predetermined time intervals.

[0084] In the flowchart shown in Fig. 4, various control information used for notification control is read in S111. The control information read in S111 includes the current position Pa, vehicle speed VSPa, and link ID of the right-turning vehicle VA, and the current position Pb, vehicle speed VSPb, and link ID of the straight-moving vehicle VB. It may also include information regarding the operation status of the right blinkers of the right-turning vehicle VA and the straight-moving vehicle VB.

[0085] In S112, it is determined whether or not another vehicle traveling in the opposite lane to the lane in which the host vehicle, right-turning vehicle VA, is located, in the straight-moving direction toward the intersection CS, i.e., straight-moving vehicle VB, has been detected. The straight-moving vehicle VB is detected based on the link ID of the straight-moving vehicle VB. If the straight-moving vehicle VB is detected, the process proceeds to S113; if not, the current control is terminated.

[0086] In S113, it is determined whether or not a right-turning intention of the right-turning vehicle VA has been detected. The detection of a right-turning intention is based on the operation status of the right blinker of the right-turning vehicle VA. In addition to or instead of this, the determination can also be based on the link ID of the right-turning vehicle VA. For example, if the right-turning lane L11 is a right-turn-only lane, the right-turning intention of the right-turning vehicle VA can be detected by checking that the lane in which the vehicle is traveling is the right-turning lane L11. If a right-turning intention is detected, proceed to S114; if not, end the current control.

[0087] In S114, the current position Pa of the right-turning vehicle VA on the road map is identified.

[0088] In S115, it is determined whether the right-turning vehicle VA has entered the intersection area ACS. Specifically, if the right-turning vehicle VA is at the outer edge of the intersection area ACS (i.e., the first predetermined position P1) or at a position closer to the intersection center CTR than this position, it is determined that it has entered the intersection area ACS, and the process proceeds to S116. On the other hand, if the right-turning vehicle VA is at a position farther from the intersection center CTR than the outer edge of the intersection area ACS, it is determined that it has not reached the intersection area ACS and is outside the intersection area ACS, and the current control is terminated.

[0089] In S116, information presentation processing is performed according to the procedure shown in the flowchart of FIG.

[0090] In S117, an alarm process is carried out according to the procedure shown in the flowchart of FIG.

[0091] In S118, it is determined whether the right-turning vehicle VA has passed through the intersection CS. The determination of whether the right-turning vehicle VA has passed through the intersection CS is made when the right-turning vehicle VA departs from the intersection area ACS in the direction of travel after turning right. If the right-turning vehicle VA has passed the intersection CS, the current control is terminated. If the right-turning vehicle VA has not passed through the intersection CS and is still within the intersection area ACS, the process returns to S116, and the information presentation process and the warning process are repeatedly executed until the right-turning vehicle VA has passed the intersection CS.

[0092] 5, various control information used in the information presentation process is read in S211. The control information read in S211 includes the current position Pa and vehicle speed VSPa of the right-turning vehicle VA and the current position Pb and vehicle speed VSPb of the straight-moving vehicle VB.

[0093] In S212, the current positions Pa and Pb on the road map of the right-turning vehicle VA and the straight-going vehicle VB are identified.

[0094] In S213, it is determined whether the right-turning vehicle VA is outside the collision prediction area ACP. Specifically, if the right-turning vehicle VA is between the outer edge of the intersection area ACS and the outer edge of the collision prediction area ACP (i.e., the second predetermined position P2), it is determined that the vehicle is outside the collision prediction area ACP, and the process proceeds to S214. If the operation status of the right blinker is used to detect the right-turning vehicle VA's intention to turn right, it may be determined whether the right blinker is still operating in addition to the process of S213, and if the right blinker is still operating, the process from S214 onwards may be carried out. On the other hand, if the vehicle VA is located on the outer edge of the collision prediction area ACP or closer to the collision prediction point CPP, it is determined that the vehicle is not outside the collision prediction area ACP, and the information presentation process is terminated.

[0095] In S214, the vehicle speed VSPa of the right-turning vehicle VA is read.

[0096] In S215, it is determined whether the vehicle speed VSPa of the right-turning vehicle VA is equal to or less than a predetermined vehicle speed VSP1. The predetermined vehicle speed VSP1 is a vehicle speed low enough to determine that the right-turning vehicle VA is traveling at a low speed, for example, a creeping speed (specifically, 10 km / h). In this embodiment, if the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, it is determined that the driver of the right-turning vehicle VA is paying attention to the surrounding conditions when passing through the intersection CS. If the vehicle speed VSPa is equal to or less than the predetermined vehicle speed VSP1, the process proceeds to S216, and if it is higher than the vehicle speed VSP1, the information presentation process is terminated. The predetermined vehicle speed VSP1 may be 0 km / h; in other words, S215 may be a process of determining whether the right-turning vehicle VA has made a temporary stop within the intersection area ACS. Furthermore, it is possible to eliminate the processing of S215 itself, and if the conditions for issuing information (S218) and the conditions for issuing an alarm (S318) described later are met simultaneously, the issuance of an alarm may be given priority over the issuance of information.

[0097] In this way, in this embodiment, after the right-turning vehicle VA enters the intersection area ACS, if it maintains a low vehicle speed VSPa or decelerates sufficiently (including when it is stopped temporarily) before reaching the collision prediction area ACP, the timing for issuing an information notification is deemed to have arrived when the vehicle speed VSPa is detected to be equal to or less than the predetermined vehicle speed VSP1, and processing from S216 onwards is carried out to determine whether the first predetermined notification condition is met.

[0098] In S216, the distance Db from the intersection CS to the straight-moving vehicle VB, in other words, the distance ahead of the straight-moving vehicle VB before reaching the intersection CS (hereinafter referred to as "intersection arrival distance") is calculated. As shown in Fig. 13, the intersection arrival distance Db is calculated as the distance from the outer edge of the predicted collision area ACP to the straight-moving vehicle VB, and this calculation is based on the current position Pb of the straight-moving vehicle VB.

[0099] In S217, the information presentation distance Dth1 is calculated based on the vehicle speed VSPb of the straight-moving vehicle VB, the relative vehicle speed RSPb, and the first predetermined deceleration DEC1, according to the procedure shown in the flowchart of FIG.

[0100] In S218, it is determined whether the intersection arrival distance Db of the straight-moving vehicle VB is equal to or less than the information presentation distance Dth1, in other words, whether the straight-moving vehicle VB is at the information presentation distance Dth1 from the intersection CS or is at a position even closer to the intersection CS. If it is equal to or less than the information presentation distance Dth1, the process proceeds to S219, and if it is longer than the information presentation distance Dth1, the information presentation process ends.

[0101] In S219, a notification of information presentation is issued.

[0102] In the flowchart shown in FIG. 6, in S217a, the vehicle speed VSPa of the subject vehicle, that is, the right-turning vehicle VA, is read.

[0103] In S217b, it is determined whether the vehicle speed VSPa of the right-turning vehicle VA is equal to or less than a predetermined vehicle speed Vth1. If the vehicle speed VSPa is equal to or less than the predetermined vehicle speed Vth1, the process proceeds to S217c, and if it is higher than the predetermined vehicle speed Vth1, the process proceeds to S217e.

[0104] In S217c, the vehicle speed VSPb of the other vehicle VB going straight is read.

[0105] In S217d, the information presentation distance Dth11 is calculated using the above formula (1.1) based on the vehicle speed VSPb of the straight-moving vehicle VB and the first predetermined deceleration DEC1.

[0106] In S217e, the vehicle speed VSPb of the straight-moving vehicle VB is read.

[0107] In S217f, the relative vehicle speed RSPb of the straight-moving vehicle VB with respect to the right-turning vehicle VA is calculated.

[0108] In S217g, the information presentation distance Dth12 is calculated using the above formula (1.2) based on the relative vehicle speed RSPb of the straight-moving vehicle VB and the first predetermined deceleration DEC1. Here, as shown in Fig. 15, the information presentation distance Dth12 calculated using the relative vehicle speed RSPb of the straight-moving vehicle VB is longer than the information presentation distance Dth11 (Fig. 13) calculated using the vehicle speed VSPb.

[0109] 7, various control information used in the warning process is read in S311. The control information read in S311 includes the current position Pa and vehicle speed VSPa of the right-turning vehicle VA and the current position Pb and vehicle speed VSPb of the straight-moving vehicle VB.

[0110] In S312, the current positions Pa and Pb on the road map of the right-turning vehicle VA and the straight-going vehicle VB are identified.

[0111] In S313, it is determined whether the right-turning vehicle VA is within the collision prediction area ACP. Specifically, if the right-turning vehicle VA is located at the outer edge of the collision prediction area ACP (i.e., the second predetermined position P2) or closer to the collision prediction point CPP than this, it is determined that it is within the collision prediction area ACP, and the process proceeds to S316. On the other hand, if it is located farther from the collision prediction point CPP than the outer edge of the collision prediction area ACP, it is determined that it is not within the collision prediction area ACP, and the process proceeds to S314. If the operation status of the right turn signal is used to detect the right turn intention of the right-turning vehicle VA, the continued operation of the right turn signal may be included as a condition for performing the process of S313.

[0112] In S314, the vehicle speed VSPa of the right-turning vehicle VA is read.

[0113] In S315, it is determined whether the vehicle speed VSPa of the right-turning vehicle VA is higher than a predetermined vehicle speed VSP1. If it is higher than the predetermined vehicle speed VSP1, the process proceeds to S316, and if it is equal to or lower than the predetermined vehicle speed VSP1, the warning process is terminated. That is, it is determined whether the vehicle speed VSPa of the right-turning vehicle VA is higher than the vehicle speed VSP1 that indicates a low-speed traveling state, for example, a slow-moving state, and if it is higher than the vehicle speed VSP1, it is determined that the driver of the right-turning vehicle VA is not paying attention to the surrounding situation, and the process proceeds to S316. On the other hand, if the vehicle speed is equal to or lower than VSP1, it is determined that a situation requires the issuance of an information presentation alert, and the warning process is terminated.

[0114] In this way, in S313 to S315, if the right-turning vehicle VA enters the intersection area ACS and then reaches the collision prediction area ACP, and is already within the collision prediction area ACP, or is outside the collision prediction area ACP but is traveling toward the collision prediction point CPP at a speed above a certain level and is approaching the collision prediction area ACP, the detection of such a situation determines that it is time to issue an alarm, and processing from S316 onwards is carried out to determine whether the second predetermined alarm condition is met.

[0115] In S316, the distance Db to the intersection of the vehicle VB going straight is calculated.

[0116] In S317, the warning distance Dth2 is calculated based on the vehicle speed VSPb of the straight-moving vehicle VB, the relative vehicle speed RSPb, and the second predetermined deceleration DEC2, according to the procedure shown in the flowchart of FIG.

[0117] In S318, it is determined whether the intersection arrival distance Db of the straight-moving vehicle VB is equal to or less than the warning distance Dth2, in other words, whether the straight-moving vehicle VB is at the warning distance Dth2 from the intersection CS or is at a position even closer to the intersection CS. If it is equal to or less than the warning distance Dth2, the process proceeds to S319, and if it is longer than the warning distance Dth2, the warning process is terminated.

[0118] In S319, an alarm is issued.

[0119] In the flowchart shown in FIG. 8, in S317a, the vehicle speed VSPa of the subject vehicle, that is, the right-turning vehicle VA, is read.

[0120] In S317b, it is determined whether the vehicle speed VSPa of the right-turning vehicle VA is equal to or less than a predetermined vehicle speed Vth1. If the vehicle speed VSPa is equal to or less than the predetermined vehicle speed Vth1, the process proceeds to S317c. If the vehicle speed VSPa is higher than the predetermined vehicle speed Vth1, the process proceeds to S317e.

[0121] In S317c, the vehicle speed VSPb of the other vehicle VB going straight is read.

[0122] In S317d, the warning distance Dth21 is calculated by the above formula (2.1) based on the vehicle speed VSPb of the straight-moving vehicle VB and the second predetermined deceleration DEC2.

[0123] In S317e, the vehicle speed VSPb of the straight-moving vehicle VB is read.

[0124] In S317f, the relative vehicle speed RSPb of the straight-moving vehicle VB with respect to the right-turning vehicle VA is calculated.

[0125] In S317g, the warning distance Dth22 is calculated using the above formula (2.2) based on the relative vehicle speed RSPb of the straight-moving vehicle VB and the second predetermined deceleration DEC2. Here, as shown in Fig. 16, the warning distance Dth22 calculated using the relative vehicle speed RSPb of the straight-moving vehicle VB is longer than the warning distance Dth21 (Fig. 14) calculated using the vehicle speed VSPb.

[0126] (Contents of notification control for straight-moving vehicles)

[0127] The steps performed by the controller 101a and the controller 101b in relation to notification control correspond to each other. Therefore, in the following description, the differences between the notification control performed by the controller 101b and the control performed by the controller 101a will be mainly described with reference to the flowcharts shown in Figures 4 to 8 as appropriate.

[0128] When the controller 101b starts the notification control, it reads various control information (S111 shown in the flowchart of FIG. 4). When it detects another vehicle, that is, a right-turn vehicle VA, existing in the right-turn lane L11 of the oncoming lane (S112), it determines whether it has detected the right-turn intention of the right-turn vehicle VA (S113). After detecting the right-turn intention, it specifies the current position Pa of the right-turn vehicle VA on the road map (S114), and determines whether the right-turn vehicle VA has entered the intersection area ACS (S115). When the right-turn vehicle VA has entered the intersection area ACS, the control continues, and information presentation processing is performed (S116), and warning processing is performed (S117). The information presentation processing and the warning processing are repeatedly performed until the right-turn vehicle VA passes through the intersection area ACS.

[0129] In the information presentation processing, after the controller 101b reads various control information used in the information presentation processing, such as the current positions Pb and Pa of the straight-ahead vehicle VB and the right-turn vehicle VA (S211), it specifies the current positions Pb and Pa of the straight-ahead vehicle VB and the right-turn vehicle VA on the road map respectively (S212). It determines whether the right-turn vehicle VA is outside the collision prediction area ACP (S213). When it is determined that the right-turn vehicle VA is outside the collision prediction area ACP, it reads the vehicle speed VSPa of the right-turn vehicle VA (S214), and determines whether the vehicle speed VSPa is less than or equal to a predetermined vehicle speed VSP1 (S215). When the vehicle speed VSPa is less than or equal to the predetermined vehicle speed VSP1, the process continues, and the intersection arrival distance Db of the straight-ahead vehicle VB is calculated (S216), and the information presentation distance Dth1 is calculated (S217). The calculation of the information presentation distance Dth1 is by the same procedure as shown in the flowchart of FIG. 6. Here, when the vehicle speed VSPb of the right-turn vehicle VA is higher than the predetermined vehicle speed Vth1 and the driver can clearly perceive the approach of the other vehicle, the information presentation distance Dth1 is calculated as a longer distance than when it is less than or equal to the predetermined vehicle speed Vth1 by adopting the relative vehicle speed RSPb (Dth11 < Dth12). When the intersection arrival distance Db is less than or equal to the information presentation distance Dth1 (S218), the information presentation is transmitted (S219).

[0130] In the alarm processing, the controller 101b reads various control information used for alarm processing, such as the current positions Pb and Pa of the straight-ahead vehicle VB and the right-turn vehicle VA (S311), and identifies the current positions Pb and Pa of the straight-ahead vehicle VB and the right-turn vehicle VA on the road map respectively (S312). It determines whether the right-turn vehicle VA is within the collision prediction area ACP (S313). When it is determined that the right-turn vehicle VA is not within the collision prediction area ACP, it reads the vehicle speed VSPa of the right-turn vehicle VA (S314), and determines whether the vehicle speed VSPa is higher than a predetermined vehicle speed VSP1 (S315). When the vehicle speed VSPa is higher than the predetermined vehicle speed VSP1, the process continues, and calculates the intersection arrival distance Db of the straight-ahead vehicle VB, which is the host vehicle (S316), and calculates the alarm distance Dth2 (S317). The calculation of the alarm distance Dth2 is based on the same procedure as shown in the flowchart of FIG. 8. Here, when the vehicle speed VSPb of the right-turn vehicle VA is higher than the predetermined vehicle speed Vth1 and the driver strongly perceives the approach of the other vehicle, the alarm distance Dth2 is calculated as a longer distance than when it is below the predetermined vehicle speed Vth1 by adopting the relative vehicle speed RSPb (Dth21 < Dth22). And when the intersection arrival distance Db is less than or equal to the alarm distance Dth2 (S318), an alarm is issued (S319).

[0131] (Description of the operation and effect) The vehicle notification system 1 according to the present embodiment has the above configuration. Hereinafter, the effects obtained by the present embodiment will be described.

[0132] First, in the traffic situation where the right-turn vehicle VA and the straight-ahead vehicle VB face each other across the intersection CS, the alarm transmission timing is set according to the relative position of the right-turn vehicle VA with respect to the intersection CS, and at this alarm transmission timing, the alarm transmission in a predetermined mode is performed on the condition that the alarm transmission condition defined for the position of the straight-ahead vehicle VB is satisfied. Thereby, it becomes possible to perform the alarm transmission in a mode corresponding to the urgency of the situation regarding the contact or collision of these vehicles VA and VB for traffic participants including the right-turn vehicle VA and the straight-ahead vehicle VB at an appropriate timing.

[0133] Specifically, when the right-turning vehicle VA is located a relatively long distance from the predicted collision point CPP and the straight-moving vehicle VB is located far enough away from the intersection CS, a warning is issued to provide information on a relatively low level of urgency regarding a contact or collision between the two vehicles.On the other hand, when the right-turning vehicle VA continues traveling at a relatively high speed after entering the intersection area ACS or reaches the predicted collision area ACP, and the straight-moving vehicle VB also approaches close to the intersection CS, a warning is issued to encourage awareness of a higher level of urgency regarding a collision between the two vehicles.

[0134] Here, when issuing an alert, alert distances Dth1 and Dth2 are calculated based on preset decelerations (i.e., a first predetermined deceleration DEC1 and a second predetermined deceleration DEC2), and if, at the time of issuing an alert, the straight-moving vehicle VB is at or closer to the intersection CS than the alert distances Dth1 and Dth2 from the intersection CS, an alert is issued in a predetermined mode, thereby enabling the alert to be issued at a timing that matches the driver's sensation (driving feeling) during deceleration. This makes it possible to prevent the driver from feeling uncomfortable or anxious due to a mismatch between the driver's sensation and the timing of issuing an alert, thereby realizing more appropriate alert issuing.

[0135] Secondly, by detecting the relative vehicle speed RSPb of the straight-moving vehicle VB relative to the right-turning vehicle VA and calculating the alarm distances Dth1 and Dth2 based on the pre-set decelerations DEC1 and DEC2 and the relative vehicle speed RSPb of the straight-moving vehicle VB, the timing of alarm activation can be reflected in the sensations that the driver actually experiences as the other vehicle approaches, and the timing of alarm activation can be made more in line with the driver's sensations, thereby further reducing situations in which the driver feels uncomfortable or uneasy.

[0136] For example, in a situation where a right-turning vehicle VA is approaching an intersection CS or an intersection center CTR at a relatively high vehicle speed VSPa, if the vehicle speed VSPb of the straight-moving vehicle VB is used to calculate the alarm distances Dth1 and Dth2, the alarm will not be issued until the straight-moving vehicle VB arrives relatively close to the intersection CS, even though the driver is keenly aware of the approach of the other vehicle. This may cause the driver to feel uncomfortable or uneasy about the timing of the alarm. According to this embodiment, the alarm can be issued at a more appropriate timing, thereby preventing such a situation and making it possible to prevent a situation in which the driver, upon noticing the presence of the other vehicle through the alarm, panics and brakes, thereby compromising safety.

[0137] Thirdly, the vehicle speed used to calculate the alarm distances Dth1 and Dth2 can be switched between absolute vehicle speed VSPb and relative vehicle speed RSPb depending on the vehicle speed VSPa of the right-turning vehicle VA. If the vehicle speed VSPa of the right-turning vehicle VA is higher than a predetermined vehicle speed Vth1, the relative vehicle speed RSPb of the straight-moving vehicle VB is adopted, while if the vehicle speed VSPa is equal to or lower than the predetermined vehicle speed Vth1, the vehicle speed VSPb (i.e., absolute vehicle speed) of the straight-moving vehicle VB is adopted. This makes it possible to issue an alarm at a more appropriate time while suppressing the adverse effects of adopting relative vehicle speed RSPb, such as the alarm distances Dth1 and Dth2 becoming longer than necessary and the driver receiving the alarm becoming careless.

[0138] Fourth, as the timing for issuing an alarm, a first alarm timing and a second alarm timing are set in which the right-turning vehicle VA is located closer to the predicted collision point CPP than at the first alarm timing, and at each of the first and second alarm timings, an alarm is issued in a predetermined mode on the condition that the alarm condition regarding the position of the straight-moving vehicle VB is met, thereby making it possible to issue an alarm at each timing in an appropriate mode according to the urgency of the situation regarding contact or collision between the right-turning vehicle VA and the straight-moving vehicle VB.

[0139] Here, the conditions for issuing an alert at the first alert timing include that the straight-moving vehicle VB is at an information presentation distance Dth1 from the intersection CS or is located closer to the intersection CS than this, and the conditions for issuing an alert at the second alert timing include that the straight-moving vehicle VB is at an alarm distance Dth2 from the intersection CS or is located closer to the intersection CS than this.Furthermore, by calculating the information presentation distance Dth1 and the alarm distance Dth2 based on different decelerations DEC1 and DEC2, it is possible to issue an alert at an appropriate timing according to the purpose of providing information and warning.

[0140] Fifth, by calculating the alarm distances Dth1 and Dth2 based on the deceleration distance corresponding to the deceleration rates DEC1 and DEC2 plus the free-running distance, it is possible to more reliably ensure that the driver has enough time to take the necessary measures in response to the alarm being issued.

[0141] In the above description, after setting the timing for alarm activation, when determining whether the alarm activation condition is met, the decelerations DEC1 and DEC2 used to calculate the alarm activation distances Dth1 and Dth2 are set to the same values ​​when the vehicle speed VSPa of the right-turning vehicle VA is higher or lower than the predetermined vehicle speed Vth1. However, without being limited to this, the decelerations DEC1 and DEC2 can also be set to different values ​​when the vehicle speed VSPa is higher or lower than the predetermined vehicle speed Vth1.

[0142] Figure 11 shows an example of such a setting, in which when the vehicle speed VSPa of the right-turning vehicle VA is higher than a predetermined vehicle speed Vth1 and the relative vehicle speed RSPb (= V22) of the straight-moving vehicle VB is used to calculate the alarm distances Dth1 and Dth2, the decelerations DEC1 and DEC2 are reduced compared to when the vehicle speed VSPb of the right-turning vehicle VA is lower than the predetermined vehicle speed Vth1 and the vehicle speed VSPb (= V21) of the straight-moving vehicle VB is used to calculate the alarm distances Dth1 and Dth2.

[0143] In this way, the first predetermined deceleration DEC1 used to calculate the information presentation distance Dth1 can be switched between a relatively high deceleration DEC11 and a lower deceleration DEC12 depending on the vehicle speed VSPa of the right-turning vehicle VA, and the second predetermined deceleration DEC2 used to calculate the warning distance Dth2 can be switched between a relatively high deceleration DEC21 and a lower deceleration DEC22 depending on the vehicle speed VSPa of the right-turning vehicle VA.

[0144] The decelerations used to calculate the alarm distances Dth1 and Dth2 (i.e., the first and second predetermined decelerations DEC1 and DEC2) can be switched depending on the vehicle speed VSPa of the right-turning vehicle VA, and when the vehicle speed VSPa of the right-turning vehicle VA is higher than the predetermined vehicle speed Vth1, the decelerations DEC1 and DEC2 are reduced compared to when the vehicle speed VSPa is lower. This allows the driver's actual perception of the approaching other vehicle to be reflected in the timing of alarm activation, and by further optimizing the timing of alarm activation, it is possible to further reduce situations that cause the driver to feel uneasy. Specifically, when the driver of the straight-moving vehicle VB actually feels a strong sensation of the approaching right-turning vehicle VA (the driver more strongly perceives the approach of the right-turning vehicle VA), the decelerations DEC1 and DEC2 can be reduced to activate the alarm at an earlier timing, and it is possible to ensure the driver has enough time to take measures such as braking in response to the alarm activation.

[0145] Furthermore, the deceleration rates DEC1 and DEC2 may be switched not only in accordance with the vehicle speed VSPa of the right-turning vehicle VA, but also, or instead, in accordance with the vehicle speed VSPb or relative vehicle speed RSPb of the straight-moving vehicle VB. For example, in calculating the information presentation distance Dth1, the first predetermined deceleration rate DEC1 is reduced as the vehicle speed VSPb or relative vehicle speed RSPb increases, and in calculating the warning distance Dth2, the second predetermined deceleration rate DEC2 is reduced as the vehicle speed VSPb or relative vehicle speed RSPb increases.

[0146] The distance Db from the intersection CS to the straight-moving vehicle VB is the distance from the outer edge of the collision prediction area ACP, specifically, the intersection of the travel path TRb of the straight-moving vehicle VB and the circle defining the outer edge of the collision prediction area ACP (the circle shown by the dashed line in the figure) to the straight-moving vehicle VB. However, the distance Db may be the distance from the collision prediction point CPP to the straight-moving vehicle VB, or the distance along the center line of the oncoming lane L22 from the right-turning vehicle VA to the straight-moving vehicle VB.

[0147] The calculation unit of the notification system 1 is composed of the controllers 101a and 101b provided in the right-turning vehicle VA or the straight-moving vehicle VB, respectively, and the controllers 101a and 101b constitute a single virtual controller. However, it is also possible to configure the notification control to be performed outside the vehicle by storing a road map and a computer program for notification control in a roadside device or a remote server. In this case, the right-turning vehicle VA and the straight-moving vehicle VB transmit their respective position information to an external controller via road-to-vehicle communication and receive a command signal that is the result of a calculation related to control. Then, based on the command signal, the controller presents information or issues an alarm.

[0148] Traffic participants to be notified are not limited to the right-turning vehicle VA and the straight-going vehicle VB, but may also be other vehicles approaching the intersection CS. An example of such a vehicle is a vehicle traveling toward the intersection CS in a lane other than the right-turn lane L11 and a lane extending parallel thereto (for example, the straight-going lane L12) among the lanes leading to the intersection CS toward which the right-turning vehicle VA is heading, specifically, a lane intersecting the right-turn lane L11 (i.e., an intersecting vehicle). Here, a vehicle other than the right-turning vehicle VA that is approaching the intersection CS and may enter the intersection CS is called an "intersection-entering vehicle," and this includes not only the straight-going vehicle VB but also an intersecting vehicle.

[0149] On the road shown in Figure 12, in a situation where there are right-turning vehicle VA, straight-going vehicle VB, and an intersecting vehicle (not shown) traveling toward intersection CS, if there are no traffic lights installed to regulate the passage of intersecting vehicles at intersection CS, the timing at which the intersecting vehicle enters intersection CS will coincide with the timing at which right-turning vehicle VA and straight-going vehicle VB enter intersection CS, raising the concern that contact or collision may occur between these vehicles.

[0150] In such a situation, after detecting the right-turning vehicle VA's intention to turn right, the notification system 1 monitors the relative positional relationship between the right-turning vehicle VA and the intersecting vehicle, in addition to or instead of controlling notifications between the right-turning vehicle VA and the straight-moving vehicle VB. As described above, the notification system 1 issues a notification based on the urgency of the situation regarding contact or collision between the right-turning vehicle VA and the intersecting vehicle at an appropriate timing between the time the right-turning vehicle VA approaches the intersection CS and the time it passes through the intersection CS. As an example, the right-turning vehicle VA and the intersecting vehicle perform the same information presentation processing and warning processing as those performed between the right-turning vehicle VA and the straight-moving vehicle VB. [Explanation of symbols]

[0151] 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-moving vehicle.

Claims

1. A vehicle turning right in the lane leading to the intersection, A vehicle notification system that issues a warning to traffic participants including a straight-moving vehicle traveling in a straight direction toward the intersection in an oncoming lane relative to the lane in which the right-turning vehicle is present, an alert timing setting means for setting an alert timing according to the relative position of the right-turning vehicle with respect to the intersection; an alert issuing means for issuing an alert in a predetermined mode to the traffic participants on the condition that an alert issuing condition determined with respect to the position of the straight-moving vehicle is satisfied at the alert issuing timing set by the alert issuing timing setting means, The alarm issuing means calculating an alarm distance based on a predetermined deceleration as a distance required for deceleration of the straight-moving vehicle; The vehicle notification system issues a notification in the predetermined mode when, at the notification timing, the straight-moving vehicle is within the notification distance from the intersection or is closer to the intersection than this.

2. a relative vehicle speed detection means for detecting a relative vehicle speed of the straight-moving vehicle with respect to the right-turning vehicle, The vehicle notification system according to claim 1 , wherein the notification means calculates the notification distance based on the deceleration and a relative vehicle speed of the straight-moving vehicle.

3. a first vehicle speed detection means for detecting a vehicle speed of the right-turning vehicle; a second vehicle speed detection means for detecting the vehicle speed of the straight-moving vehicle, 3. The vehicle warning system of claim 2, wherein the alarm issuing means calculates the warning distance based on the deceleration and the relative vehicle speed of the straight-moving vehicle when the vehicle speed of the right-turning vehicle detected by the first vehicle speed detection means is higher than a predetermined vehicle speed, and calculates the warning distance based on the deceleration and the vehicle speed of the straight-moving vehicle detected by the second vehicle speed detection means when the vehicle speed of the right-turning vehicle is lower than the predetermined vehicle speed.

4. The vehicle notification system according to claim 2 , wherein the notification means calculates the notification distance by switching the deceleration rate in accordance with a vehicle speed of the right-turning vehicle.

5. The vehicle notification system according to claim 2 , wherein the alarm issuing unit calculates the alarm distance by switching the deceleration rate in accordance with a vehicle speed of the straight-moving vehicle or a relative vehicle speed of the straight-moving vehicle.

6. The vehicle notification system according to claim 3 , wherein the alarm issuing unit calculates the alarm distance by switching the deceleration rate depending on whether the vehicle speed of the right-turning vehicle is higher or lower than the predetermined vehicle speed.

7. The vehicle notification system according to claim 6, wherein the notification means reduces the deceleration when the vehicle speed of the right-turning vehicle is higher than the predetermined vehicle speed compared to when the vehicle speed is lower than the predetermined vehicle speed.

8. a point where a route along which the right-turning vehicle will travel when passing through the intersection and a route along which the straight-moving vehicle will travel when passing through the intersection intersect is set as a collision prediction point, and the alert timing setting means sets, as the alert timings, a first alert timing and a second alert timing at which the right-turning vehicle is located closer to the collision prediction point than the first alert timing; the alert issuing means issues an alert in the predetermined mode on condition that the alert condition is satisfied at each of the first alert timing and the second alert timing set by the alert timing setting means, The alarm issuing means the alert condition at the first alert timing includes that the straight-moving vehicle is at a first alert distance from the intersection or is at a position closer to the intersection than the first alert distance, the alert condition at the second alert timing includes that the straight-moving vehicle is at a second alert distance from the intersection that is shorter than the first alert distance, or is at a position closer to the intersection than the second alert distance, The deceleration includes a first predetermined deceleration and a second predetermined deceleration higher than the first predetermined deceleration, 2. The vehicle notification system according to claim 1, wherein the first alarm distance is calculated based on the first predetermined deceleration, and the second alarm distance is calculated based on the second predetermined deceleration.

9. 2. The vehicle notification system according to claim 1, wherein the notification means calculates the notification distance based on a distance obtained by adding a predetermined free running distance to a deceleration distance corresponding to the deceleration.

Images