Intersection Support Target Extraction System and Vehicle Support Device

Abstract

To provide a support object intersection extraction system for appropriately extracting a support object intersection to be an object of vehicle support of a support object vehicle.SOLUTION: A support object intersection extraction system extracts a support object intersection to be an object of vehicle support in a support object vehicle from among intersections included in map information and comprises: a priority road extraction unit which extracts a priority road among roads connecting with the intersection on the basis of position information, travel information acquired from a plurality of probe vehicles and the map information; a risk reduction amount calculation unit which calculates a risk reduction amount of an intersection on a priority road side at the intersection from which the priority road is extracted on the basis of the position information and the travel information acquired from the plurality of probe vehicles; and a support object intersection extraction unit which extracts the support object intersection from among intersections at which a travel road of the support object vehicle is the priority road and the risk reduction amount is less than a risk reduction amount threshold.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a support target intersection extraction system and a vehicle support device.

Background Art

[0002] Conventionally, as a technical document related to a support target intersection extraction system, Japanese Unexamined Patent Application Publication No. 2020-140310 is known. This publication shows that in an evaluation device that evaluates risks existing around a road on which a vehicle travels, risks of curves and intersections are determined based on the driving behavior of the driver of the vehicle.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Although risk factors vary depending on the environment around an intersection, there has been a problem that the prior art cannot identify risk factors. In the prior art, when it is desired to extract and support only the scenes in which the driver predicts a risk of jumping out and performs deceleration or steering in advance to reduce the collision risk, it cannot be used for its realization.

Means for Solving the Problems

[0005] One aspect of the present invention is to determine, from intersections included in map information, in a support target vehicle Including deceleration support or avoidance supportA support target intersection extraction system for extracting support target intersections to be supported by a vehicle, comprising: a priority road extraction unit that extracts a priority road from roads connected to an intersection based on position information and driving information acquired from a plurality of probe vehicles and map information; and a risk reduction amount calculation unit that calculates a risk reduction amount based on the position information and driving information acquired from the plurality of probe vehicles, As the difference between the risk value when a pedestrian jumps out from a non-priority road at an intersection in the risk avoidance behavior actually taken by a probe vehicle traveling on the priority road side of the intersection where the priority road has been extracted, and the risk value when a pedestrian jumps out from a non-priority road at the intersection assuming that the probe vehicle did not take risk avoidance behavior and a support target intersection extraction unit that extracts a support target intersection from intersections where the driving road of the support target vehicle is a priority road and the risk reduction amount is less than a risk reduction amount threshold. Based on the detection results of the external sensors of the vehicle to be supported, a shielding determination unit that determines whether or not the intersecting road that intersects the traveling road of the vehicle to be supported at an intersection is shielded as viewed from the traveling road Among them, at intersections where the intersecting road is determined to be shielded as viewed from the traveling road For vehicle support, it is deceleration support for the vehicle to be supported .

[0007] Another aspect of the present invention is a vehicle support device that performs vehicle support for a support target vehicle at a support target intersection extracted by the above-described support target intersection extraction system. The vehicle support device includes a vehicle control unit that executes a collision damage reduction brake as vehicle support based on a detection result of an external sensor of the support target vehicle. The vehicle control unit relaxes the operating conditions of the collision damage reduction brake at the support target intersection compared to the operating conditions at other intersections.

Effects of the Invention

[0008] According to one aspect of the present invention, it is possible to appropriately extract a support target intersection that is the target of vehicle support for a support target vehicle.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Best Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0011] FIG. 1 is a diagram showing an extraction system for an intersection to be supported according to the present embodiment. The extraction system 1 for an intersection to be supported shown in FIG. 1 includes a server 10 and an ECU of a vehicle 2A to be supported. The extraction system 1 for an intersection to be supported is a system that extracts an intersection to be supported, which is an intersection that is the target of vehicle support for the vehicle 2A to be supported, from among intersections on a map. The vehicle 2A to be supported is a vehicle that executes vehicle support. Vehicle support is, for example, AEBS [Autonomous Emergency Braking System] (Collision Damage Reduction Brake), deceleration support, and avoidance support. The content of vehicle support is not particularly limited.

[0012] The server 10 is communicably connected to probe vehicles 2 (probe vehicles 2A to 2Z) via a network N. The network N is a wireless communication network. The network N may be a communication network for mobile phones or the Internet. The network N is not particularly limited, and well-known technologies can be adopted.

[0013] The probe vehicle 2 is a vehicle that provides the server 10 with position information and driving information as probe data. The position information and driving information may be associated with time. The probe vehicle 2 includes, for example, probe vehicles 2A to 2Z. The probe vehicle 2 may be composed of two or more vehicles. In the present embodiment, the vehicle 2A to be supported also provides information to the server 10 as the probe vehicle 2. Note that the vehicle 2A to be supported may be a vehicle that only obtains information for vehicle support from the server 10 without providing information to the server 10. The probe vehicle 2 and / or the vehicle 2A to be supported may be an autonomous driving vehicle.

[0014] The map database 50 is a database that stores map information. The map information includes road location information, road shape information, intersection location information, etc. The map information may be stored in the form of road links and intersection nodes. Also, the map information may include information on the presence or absence of traffic lights at intersections.

[0015] The density probe database 51 is a database that stores the location information and driving information of each probe vehicle 2 collected from the traveling probe vehicle 2. The driving information includes vehicle speed information. The driving information may also include longitudinal acceleration information and lateral acceleration information. The density probe data is easier to collect by communication compared to the high-density probe data, and various data can be constantly collected from a large number of probe vehicles 2.

[0016] The support target intersection candidate database 52 is a database that stores support target intersection candidates. A support target intersection candidate is an intersection that is a candidate for a support target intersection.

[0017] Figure 2 is a diagram showing the configuration of the server. As shown in Figure 2, the server 10 has a processor 11, a storage unit 12, a communication unit 13, and a user interface 14. The server 10 may have a storage unit in addition to various databases.

[0018] The processor 11 controls the server 10 by operating, for example, an operating system. The processor 11 is an arithmetic unit such as a CPU [Central Processing Unit] that includes a control device, an arithmetic device, registers, etc. The processor 11 oversees the communication unit 13 and the user interface 14. The processor 11 controls the data transmission and reception with the map database 50, the density probe database 51, and the support target intersection candidate database 52.

[0019] The memory unit 12 may be a ROM and / or a RAM, or may be a storage medium such as an HDD configured in a RAID [Redundant Arrays of Inexpensive Disks] configuration. The communication unit 13 is a communication device for performing communication via the network N. For the communication unit 13, a network device, a network controller, a network card, etc. can be used. The user interface 14 is a device including output devices such as a display and a speaker, and input devices such as a touch panel.

[0020] Next, the functional configuration of the server 10 will be described. As shown in FIG. 2, the processor 11 of the server 10 has a priority road extraction unit 11a, a risk reduction amount calculation unit 11b, and a candidate storage unit 11c.

[0021] The priority road extraction unit 11a extracts a priority road from the roads connecting to an intersection based on the map information stored in the map database 50 and the position information and driving information of each probe vehicle 2 stored in the density probe database 51. The priority road is a road with a high driving priority at an intersection where no signal is provided.

[0022] Based on the mapping results of the trajectories and vehicle speed changes of each probe vehicle 2 entering the intersection, the priority road extraction unit 11a uses the feature that vehicles traveling on the priority road have a small reduction in vehicle speed, and vehicles traveling on non-priority roads (roads that are not priority roads at the intersection) have an average vehicle speed approaching zero due to a temporary stop, to extract a priority road from the roads connecting to the intersection.

[0023] For example, the priority road extraction unit 11a determines, from the vehicle speed changes corresponding to the positions of a plurality of probe vehicles 2 approaching the intersection by traveling on the roads intersecting each other at the intersection, that a road with an average value of the vehicle speed of the probe vehicle 2 in front of the intersection being near zero (for example, less than 5 km / h) is a non-priority road, and extracts, as a priority road, a road among the roads intersecting the non-priority road where the average value of the vehicle speed reduction amount of the probe vehicle 2 in front of the intersection is less than a certain threshold value. The values of the determination threshold near zero and the certain threshold value are not particularly limited.

[0024] The priority road extraction unit 11a may determine the presence or absence of a traffic signal at an intersection. When the map information includes information on the presence or absence of a traffic signal at an intersection, the priority road extraction unit 11a determines the presence or absence of a traffic signal at the intersection based on the map information. Since vehicles stopping at a red signal and vehicles passing at a green signal are mixed at intersections with traffic signals, the priority road extraction unit 11a may also determine the presence or absence of a traffic signal at an intersection based on the vehicle speed information of the probe vehicle 2.

[0025] Based on the position information and driving information acquired from a plurality of probe vehicles, the risk reduction amount calculation unit 11b calculates the risk reduction amount at the intersection on the priority road side at the intersection where the priority road is extracted.

[0026] The risk reduction amount may be obtained, for example, as an average value calculated by calculating the difference in the risk values for the same intersection for a predetermined number of probe vehicles 2 from a certain distance (for example, 20 m) in front of the intersection to 0 m assuming no change in the vehicle speed and steering of the probe vehicle 2. The predetermined number can be 10 or more, and may be 50 or 80. In other words, the risk reduction amount can be obtained as the difference in the risk values calculated respectively from the behavior (trajectory and vehicle speed change) actually taken by the probe vehicle 2 with awareness of risk avoidance (for example, a pedestrian jumping out) at the intersection and the behavior assuming that the probe vehicle 2 did not take risk avoidance.

[0027] As a method for obtaining the risk (quantification method), a method using the risk field described in Japanese Patent Application Laid-Open No. 2017-206117 can be adopted. Since this method is used for comparison between intersections, the assumed values of the jumping-out speed of traffic participants (such as pedestrians and other vehicles) and the deceleration of the own vehicle in the risk field are not particularly limited. For example, by calculating the values of the risk field in the case of assuming that traffic participants are not avoided at the intersection every 100 m per second and the case of the actual driving of the probe vehicle 2, and accumulating the difference until passing through the intersection, it is possible to quantitatively calculate how much risk avoidance behavior the driver of the probe vehicle 2 has taken.

[0028] FIG. 3 is a diagram for explaining an example of the calculation of the risk reduction amount. FIG. 3 shows an intersection T of a crossroads, a priority road R1, a non-priority road R2, a probe vehicle 2B, and a wall W. The priority road R1 is a driving road on which the probe vehicle 2B travels. The non-priority road R2 is an intersecting road that intersects with the priority road R1 at the intersection T. The vehicle speed of the probe vehicle 2B is 40 km / h. The wall W is formed so as to shield the non-priority road R2 (intersecting road) as viewed from the priority road R1 (driving road) on which the probe vehicle 2B travels. That is, from the driver of the probe vehicle 2B, a traffic participant (for example, a pedestrian P) jumping out from the non-priority road R2 cannot be visually recognized. The intersection T is an intersection with poor visibility.

[0029] Also, FIG. 3 shows an actual travel locus Cr and a virtual travel locus Cv of the probe vehicle 2B. In the actual travel locus Cr, the probe vehicle 2B travels so as to keep a distance from the entrance of the intersection T of the non-priority road R2 while decelerating to 30 km / h in consideration of the possibility that a traffic participant such as a pedestrian P jumps out from the non-priority road R2 on the left. On the other hand, the virtual travel locus Cv shows the case where the probe vehicle 2B goes straight without decelerating.

[0030] The risk reduction amount calculation unit 11b calculates the difference in the risk field value between the case of the virtual travel locus Cv and the case of the actual travel locus Cr in the section from the probe vehicle 2B shown in FIG. 3 to the entrance of the intersection T as the risk reduction amount. In the risk field, when the speed of the pedestrian P is 2 m / s, it is assumed that in the actual travel locus Cr, 0.5 s of time can be gained by being 1 m away from the non-priority road R2, and as a result, it is considered that the collision speed can be reduced by 17 km / h.

[0031] The candidate storage unit 11c extracts candidate supported intersection points and stores them in the supported intersection point candidate database 52. The candidate storage unit 11c extracts, as candidate supported intersection points, intersection points among the intersection points included in the map information for which the risk reduction amount is less than the risk reduction amount threshold value. The risk reduction amount threshold value is a preset threshold value. The risk reduction amount threshold value may be set to an arbitrary value by the system administrator. The candidate storage unit 11c may extract, as candidate supported intersection points, intersection points without traffic signals among the intersection points for which the risk reduction amount is less than the risk reduction amount threshold value.

[0032] The candidate storage unit 11c stores the candidate supported intersection points in the supported intersection point candidate database 52. The candidate storage unit 11c may store the candidate supported intersection points as latitude and longitude information, or may store the candidate supported intersection points in association with the intersection nodes of the map information. The candidate storage unit 11c stores the candidate supported intersection points in association with the priority road (or intersection approach direction). The candidate storage unit 11c may set a risk level for each candidate supported intersection point. The risk level is the degree of risk according to the environment of the intersection.

[0033] In addition to the position information of the candidate supported intersection points, the candidate storage unit 11c may store risk-taking amount data in the supported intersection point candidate database 52. The risk-taking amount data is data obtained by calculating how much risk the driver of the probe vehicle 2 has taken in the candidate supported intersection point in accordance with the concept of the above-described risk field. The risk-taking amount data is obtained from the average of the driving data of a plurality of probe vehicles 2, and is different from the above-described risk level.

[0034] In addition to the position information of the candidate supported intersection points, the candidate storage unit 11c may store sudden deceleration occurrence information (near miss information) in the supported intersection point candidate database 52. The sudden deceleration occurrence information means that sudden deceleration is required due to, for example, a pedestrian jumping out at the candidate supported intersection point. The candidate storage unit 11c may set the risk level of the candidate supported intersection point where sudden deceleration has occurred to a higher value than when sudden deceleration has not occurred.

[0035] When the data transmitted from the probe vehicle 2 includes the captured image by the front camera of the probe vehicle 2, the candidate storage unit 11c may determine whether the intersection candidate to be assisted is an intersection with poor visibility by a well-known image recognition process. The candidate storage unit 11c may store the determination result of whether it is an intersection with poor visibility in the support target intersection candidate database 52 in association with the support target intersection candidate. The candidate storage unit 11c may set the risk level of the support target intersection candidate determined to be an intersection with poor visibility to a higher value than when it is not determined to be an intersection with poor visibility.

[0036] When the map information of the map database 50 includes information on the road width, the candidate storage unit 11c may determine whether the road is a narrow road with a road width equal to or less than a certain value. The candidate storage unit 11c may store the determination result of whether it is a narrow road in the support target intersection candidate database 52 in association with the support target intersection candidate. The candidate storage unit 11c may set the risk level of the support target intersection candidate determined to be a narrow road to a higher value than when it is not determined to be a narrow road.

[0037] When the map information of the map database 50 includes information on the intersection environment such as the presence or absence of a crosswalk, the candidate storage unit 11c may store the information on the support target intersection candidate and the intersection environment in the support target intersection candidate database 52 in association with each other. It is possible to devise the use of this information for extracting the support target intersection.

[0038] Next, the functional configuration of the support target vehicle 2A will be described. FIG. 4 is a diagram showing the functional configuration of the support target vehicle 2A. As shown in FIG. 4, the support target vehicle 2A has an ECU 20. The ECU 20 is an electronic control unit having a CPU, a ROM, a RAM, and the like. The ECU 20 functions as a vehicle support device.

[0039] The ECU 20 is connected to a GNSS [Global Navigation Satellite System] receiver unit 21, an external sensor 22, an internal sensor 23, a map database 24, a communication unit 25, and an actuator 26.

[0040] The GNSS receiver unit 21 measures the position (e.g., latitude and longitude) of the vehicle 2A to be supported by receiving signals from a plurality of GNSS satellites. The GNSS receiver unit 21 transmits the measured position information of the vehicle 2A to be supported to the ECU 20.

[0041] The external sensor 22 is an in-vehicle sensor that detects the external environment of the vehicle 2A to be supported. The external sensor 22 includes at least a camera. The camera is an imaging device that images the external environment of the vehicle 2A to be supported. The camera is provided, for example, on the back side of the front glass of the vehicle 2A to be supported and images the front of the vehicle. The camera transmits imaging information regarding the external environment of the vehicle 2A to be supported to the ECU 20. The camera may be a monocular camera or a stereo camera. A plurality of cameras may be provided, and in addition to the front of the vehicle 2A to be supported, the left and right sides and the rear of the vehicle 2A to be supported may be imaged.

[0042] The external sensor 22 may include a radar sensor. The radar sensor is a detection device that detects an object around the vehicle 2A to be supported using radio waves (e.g., millimeter waves) or light. The radar sensor includes, for example, a millimeter-wave radar or a lidar [Light Detection and Ranging]. The radar sensor transmits radio waves or light to the periphery of the vehicle 2A to be supported and detects an object by receiving the radio waves or light reflected by the object. The radar sensor transmits the detected object information to the ECU 20.

[0043] The internal sensor 23 is an in-vehicle sensor that detects the driving state of the vehicle 2A to be supported. The internal sensor 23 includes a vehicle speed sensor, an acceleration sensor, and a yaw rate sensor. The vehicle speed sensor is a detector that detects the speed of the vehicle 2A to be supported. As the vehicle speed sensor, a wheel speed sensor provided for the wheels of the vehicle 2A to be supported or a drive shaft that rotates integrally with the wheels and that detects the rotational speed of each wheel can be used. The vehicle speed sensor transmits the detected vehicle speed information (wheel speed information) to the ECU 20.

[0044] The acceleration sensor is a detector that detects the acceleration of the vehicle 2A to be supported. The acceleration sensor includes, for example, a longitudinal acceleration sensor that detects the longitudinal acceleration of the vehicle 2A to be supported. The acceleration sensor may include a lateral acceleration sensor that detects the lateral acceleration of the vehicle 2A to be supported. The acceleration sensor transmits, for example, the acceleration information of the vehicle 2A to be supported to the ECU 20. The yaw rate sensor is a detector that detects the yaw rate (rotational angular velocity) around the vertical axis of the center of gravity of the vehicle 2A to be supported. As the yaw rate sensor, for example, a gyro sensor can be used. The yaw rate sensor transmits the detected yaw rate information of the vehicle 2A to be supported to the ECU 20.

[0045] The map database 24 is a database that stores map information. The map database 24 is formed, for example, in a storage device such as an HDD [Hard Disk Drive] mounted on the host vehicle. The map information includes, for example, road position information, road shape information, intersection position information, and the like.

[0046] The communication unit 25 is a communication device that controls wireless communication with the outside of the vehicle 2A to be supported. The communication unit 25 transmits and receives various information through communication with the server 10. When the vehicle 2A to be supported functions as a probe vehicle, the communication unit 25 transmits the position information and driving information of the vehicle 2A to be supported to the server 10.

[0047] In addition, the communication unit 25 acquires information on candidate intersections to be supported from the server 10 for use in vehicle support of the vehicle 2A to be supported. The communication unit 25 acquires information on candidate intersections to be supported related to the vehicle 2A to be supported from the server 10 (the candidate intersection database 52), for example, by transmitting the position information of the vehicle 2A to be supported to the server 10. The communication unit 25 may transmit information on the driving road on which the vehicle 2A to be supported is traveling to the server 10, or may transmit the target route of the navigation system to the server 10. The candidate intersections to be supported related to the vehicle 2A to be supported are candidate intersections to be supported where the driving road of the vehicle 2A to be supported is a priority road.

[0048] The actuator 26 is a device used for controlling the vehicle 2A to be supported. The actuator 26 includes at least a drive actuator, a brake actuator, and a steering actuator.

[0049] Next, an example of the functional configuration of the ECU 20 will be described. The ECU 20 has a vehicle position acquisition unit 31, an occlusion determination unit 32, a support target intersection extraction unit 33, and a vehicle control unit 34.

[0050] The vehicle position acquisition unit 31 acquires the position of the vehicle 2A to be supported based on the position information measured by the GNSS reception unit 21 and the map information of the map database 24. Note that the vehicle position acquisition unit 31 may use the position information of fixed obstacles such as utility poles included in the map information of the map database 24 and the detection results of the external sensor 22 to recognize the position of the vehicle 2A to be supported by SLAM [Simultaneous Localization and Mapping] technology.

[0051] The vehicle position acquisition unit 31 determines whether there is a candidate intersection to be supported on the driving road of the vehicle 2A to be supported based on the information on the candidate intersection to be supported acquired from the server 10 via the communication unit 25 and the position of the vehicle 2A to be supported. The vehicle position acquisition unit 31 may determine that there is a candidate intersection to be supported on the driving road when the vehicle 2A to be supported approaches the candidate intersection to be supported.

[0052] When the support target vehicle 2A approaches the support target intersection candidate, for example, it is when the distance between the support target vehicle 2A and the support target intersection candidate becomes less than a certain distance. The certain distance may be, for example, 20 m or 30 m. The certain distance is not particularly limited. The occlusion determination unit 32 may determine that the support target vehicle 2A has approached the support target intersection candidate when the remaining time until the support target vehicle 2A reaches the support target intersection candidate becomes less than a certain time.

[0053] Based on the detection result of the external sensor 22, the occlusion determination unit 32 determines whether or not the intersecting road that intersects with the traveling road at the support target intersection candidate is occluded as viewed from the traveling road. The state where the intersecting road that intersects with the traveling road is occluded as viewed from the traveling road is, for example, a state where the visual recognition of the intersecting road (non-priority road) R2 is obstructed as viewed from the traveling road (priority road) R1 by the wall W as shown in FIG. 3.

[0054] For example, when the occlusion determination unit 32 detects a structure (including natural structures such as trees and rocks) that occludes the visual recognition of the intersecting road of the support target intersection candidate by means of a camera or a radar sensor of the external sensor 22, it determines that the intersecting road is occluded as viewed from the traveling road.

[0055] The support target intersection extraction unit 33 extracts a support target intersection from among the intersections (support target intersection candidates) where the traveling road of the support target vehicle 2A is a priority road and the risk reduction amount is less than the risk reduction amount threshold.

[0056] The support target intersection extraction unit 33 extracts, as a support target intersection, an intersection determined by the occlusion determination unit 32 to have an intersecting road occluded as viewed from the traveling road among the support target intersection candidates.

[0057] The support target intersection extraction unit 33 may extract, as support target intersections, intersections among the support target intersection candidates where the intersecting road is determined to be blocked as seen from the driving road and the risk level is equal to or higher than a certain value. The support target intersection extraction unit 33 may extract, as support target intersections, intersections among the support target intersection candidates where the intersecting road is determined to be blocked as seen from the driving road and deceleration information is associated with the intersection.

[0058] Also, the support target intersection extraction unit 33 may extract, as support target intersections, intersections among the support target intersection candidates where the intersecting road is determined to be blocked as seen from the driving road and a determination result indicating that it is a narrow road or an intersection with poor visibility is associated with the intersection. The support target intersection extraction unit 33 may perform the extraction of support target intersections by using in combination the risk level, the risk-taking amount, deceleration information, and the determination result indicating that it is a narrow road or an intersection with poor visibility.

[0059] The vehicle control unit 34 executes various vehicle supports for the support target vehicle 2A based on the detection result of the external sensor 22. For example, when the distance from the support target vehicle 2A to the support target intersection becomes less than the support start distance, the vehicle control unit 34 starts deceleration mitigation support and lateral avoidance support.

[0060] The deceleration mitigation support is a vehicle support for gently decelerating the support target vehicle 2A. The lateral avoidance support is a vehicle support for performing steering or steering assistance (such as reducing steering reaction force) of the support target vehicle 2A so as to move away from the blocked intersecting road. The vehicle control unit 34 may execute only one of the deceleration mitigation support and the lateral avoidance support. Thereby, the vehicle control unit 34 can support the driver's risk reduction driving at the support target intersection.

[0061] When the vehicle control unit 34 acquires the risk level associated with the support target intersection candidate from the server 10, the vehicle control unit 34 may determine the support amount according to the risk level. For example, the higher the risk level, the larger the support amount. The support amount is, for example, the deceleration amount in the deceleration mitigation support and the lateral avoidance amount (separation distance from the intersecting road) in the lateral avoidance support.

[0062] When the vehicle control unit 34 acquires risk-taking amount data (data on the risk-taking amounts of a plurality of probe vehicles 2) associated with the intersection candidates to be supported from the server 10, it can perform vehicle support with less discomfort for general drivers by determining the support amount using the average value of the risk-taking amounts. The vehicle control unit 34 may determine the support amount using both the risk-taking amount and the risk level.

[0063] The vehicle control unit 34 may adjust the degree of support according to the driver's preference for vehicle support. For example, based on the driver's input, the vehicle control unit 34 sets the driver's preference for vehicle support in three levels: high sensitivity, medium sensitivity, and low sensitivity. At this time, if the variance of the risk-taking amount is used, with "high sensitivity: general driver - 1σ", "medium sensitivity: average of general drivers", and "low sensitivity: general driver + 1σ", it is possible to obtain a support amount that corresponds to the risk-taking amount of the intersection to be supported and reflects the driver's preference.

[0064] The vehicle control unit 34 may make the operating conditions of the collision damage mitigation brake at the intersection to be supported looser than those at other intersections. Making the operating conditions of the collision damage mitigation brake looser means making it easier to operate the collision damage mitigation brake.

[0065] For example, regarding the collision margin time [TTC: Time to Collision] between the vehicle 2A to be supported and the obstacle as the operating condition of the collision damage mitigation brake, the vehicle control unit 34 may set a larger value for the operating threshold at the intersection to be supported than at other intersections. Also, the vehicle control unit 34 may set a smaller value for the required threshold of the obstacle recognition reliability of the external sensor 22 as the operating condition of the collision damage mitigation brake than at other intersections. Thereby, the vehicle control unit 34 can operate the collision damage mitigation brake at the moment when a traffic participant becomes slightly visible from the intersecting road shielded by the wall W or the like at the intersection to be supported, and can perform appropriate collision avoidance.

[0066] When the vehicle control unit 34 has the sudden deceleration occurrence information (near miss information) associated with the intersection to be supported and stored in the support target intersection candidate database 52, the operating conditions for vehicle support may be relaxed compared to the operating conditions at other intersections. For example, the vehicle control unit 34 may relax the operating conditions of the collision damage reduction brake only when the sudden deceleration occurrence information is associated with and stored in the intersection to be supported, compared to the operating conditions at other intersections.

[0067] [Processing of Support Target Intersection Extraction System] Next, the processing of the support target intersection extraction system 1 according to the present embodiment will be described with reference to the drawings. FIG. 5 is a flowchart showing an example of the storage process of support target intersection candidates. The storage process of support target intersection candidates is executed at regular intervals.

[0068] As shown in FIG. 5, the server 10 of the support target intersection extraction system 1, as S1, recognizes the probe data transmitted from the probe vehicle 2. The server 10 acquires position information and driving information as probe data from a plurality of probe vehicles 2 via the network N.

[0069] In S2, the server 10 extracts intersections from the map information in the map database 50. Note that the extraction range of intersections may be narrowed down to an arbitrary range.

[0070] In S3, the server 10 extracts a priority road from the roads connecting to the intersection by the priority road extraction unit 11a. For example, the priority road extraction unit 11a extracts, as a priority road, a road for which the average value of the vehicle speed reduction amount of the probe vehicle 2 in front of the intersection is less than a certain threshold value, based on the vehicle speed changes corresponding to the positions of a plurality of probe vehicles 2 that travel on the roads intersecting each other at the intersection and approach the intersection.

[0071] In S4, the server 10 performs traffic signal determination by the priority road extraction unit 11a. When the map information includes information on the presence or absence of traffic signals at intersections, the priority road extraction unit 11a determines the presence or absence of traffic signals at intersections based on the map information. The priority road extraction unit 11a may also determine the presence or absence of traffic signals at intersections based on the vehicle speed information of the probe vehicle 2.

[0072] In S5, the server 10 calculates the risk reduction amount at the intersection on the priority road side at the intersection where the priority road is extracted by the risk reduction amount calculation unit 11b. The risk reduction amount calculation unit 11b calculates, for example, the difference in the risk field values between the case of the provisional driving trajectory Cv and the case of the actual driving trajectory Cr in the section from the probe vehicle 2B shown in FIG. 3 to the entrance of the intersection T as the risk reduction amount.

[0073] In S6, the server 10 extracts and stores support target intersection candidates by the candidate storage unit 11c. The candidate storage unit 11c extracts, for example, intersections where a priority road is extracted, there are no traffic signals, and the risk reduction amount is less than the risk reduction amount threshold as support target intersection candidates. The candidate storage unit 11c stores the support target intersection candidates in the support target intersection candidate database 52. The candidate storage unit 11c sets a risk level for each support target intersection candidate and stores it in association with the support target intersection candidate.

[0074] Next, the processing of the ECU 20 (vehicle support device) of the support target vehicle 2A according to the present embodiment will be described with reference to the drawings. FIG. 6 is a flowchart showing an example of vehicle support processing at a support target intersection. The vehicle support processing at the support target intersection is executed, for example, when the driver turns on the vehicle support function.

[0075] As shown in FIG. 6, as S10, the ECU 20 determines, by the vehicle position acquisition unit 31, whether there is a support target intersection candidate on the driving road of the support target vehicle 2A. When it is determined that there is a support target intersection candidate on the driving road (S10: YES), the ECU 20 proceeds to S11. When it is determined that there is no support target intersection candidate on the driving road (S10: NO), the ECU 20 ends the vehicle support process for the current support target intersection.

[0076] In S11, the ECU 20 determines, by the shielding determination unit 32, whether the intersecting road that intersects the driving road at the support target intersection candidate is shielded as seen from the driving road. The shielding determination unit 32 makes the above determination based on the detection result of the external sensor 22. When it is determined that the intersecting road is shielded as seen from the driving road (S11: YES), the ECU 20 proceeds to S12. When it is determined that the intersecting road is not shielded as seen from the driving road (S11: NO), the ECU 20 ends the vehicle support process for the current support target intersection.

[0077] In S12, the ECU 20 extracts the support target intersection by the support target intersection extraction unit 33. The support target intersection extraction unit 33 extracts, as the support target intersection, the support target intersection candidate determined by the shielding determination unit 32 to be shielded as seen from the driving road. The support target intersection extraction unit 33 may extract the support target intersection by comprehensively using the determination results of the risk level, the risk-taking amount, the sudden deceleration information, and the intersection being a narrow road or having poor visibility.

[0078] In S13, the ECU 20 executes vehicle support at the support target intersection by the vehicle control unit 34. The vehicle control unit 34 executes vehicle support such as deceleration assistance and lateral avoidance support for the support target intersection.

[0079] According to the support target intersection extraction system 1 described above, by extracting support target intersections from intersections where the driving road of the support target vehicle is a priority road and the risk reduction amount is less than the risk reduction amount threshold, it is possible to appropriately extract support target intersections that are the targets of vehicle support for the support target vehicle.

[0080] Also, in the support target intersection extraction system 1, the shielding determination unit 32 determines whether the intersecting road that intersects with the driving road at the support target intersection candidate is shielded as seen from the driving road, and extracts the intersection where the intersecting road is shielded as seen from the driving road as the support target intersection. Therefore, vehicle support can be performed so as to reduce the risk of a traffic participant jumping out from the intersecting road.

[0081] Furthermore, in the support target intersection extraction system 1, since intersections without traffic lights are extracted as support target intersections, vehicle support can be performed so as to reduce the risk at intersections where traffic participants are likely to jump out from the intersecting road due to the absence of traffic lights.

[0082] In addition, according to the ECU 20 (vehicle support device) of the support target vehicle 2A, in the vehicle control unit 34, by making the operating conditions of the collision damage reduction brake at the support target intersection looser than the operating conditions at other intersections, vehicle support can be performed so as to reduce the risk at support target intersections where traffic participants are likely to jump out from the intersecting road.

[0083] As described above, the embodiments of the present invention have been described, but the present invention is not limited to the above-described embodiments. The present invention can be implemented in various forms with various changes and improvements based on the knowledge of those skilled in the art, including the above-described embodiments.

[0084] All functions of the support target intersection extraction system 1 may be installed in a single support target vehicle 2A. That is, in the ECU 20 of the support target vehicle 2A, priority road determination and risk reduction amount calculation may be performed based on the position information and driving information transmitted from the probe vehicle 2.

[0085] The server 10 does not necessarily need to grasp the information on the presence or absence of traffic lights at intersections from the map information. The server 10 may estimate that an intersection has no traffic lights based on the extraction result of the priority road. When the server 10 extracts an intersection where the priority road and the non-priority road intersect, the server 10 may also estimate that the intersection has no traffic lights.

[0086] Moreover, the server 10 does not necessarily need to grasp any information on the presence or absence of traffic lights. In the ECU 20 of the vehicle 2A to be supported, it may be a mode of determining the presence or absence of traffic lights at the intersection in front of the vehicle 2A to be supported from the captured image of the camera.

[0087] The method for obtaining the risk reduction amount is not limited to the above content. The risk reduction amount calculation unit 11b may obtain, as the risk reduction amount, a value proportional to the distance at which the actual driving trajectory Cr separates from the non-priority road R2 at the intersection T in the situation shown in FIG. 3, or may use, as the risk reduction amount, the difference in the collision speed between the actual driving trajectory Cr and the hypothetical driving trajectory Cv when it is assumed that a pedestrian running at a constant speed jumps out from the non-priority road R2.

[0088] The ECU 20 of the vehicle 2A to be supported does not necessarily need to have the occlusion determination unit 32. In the extraction of the intersection to be supported, occlusion determination may not be used, and instead, the determination result of an intersection with poor visibility in the server 10 may be used.

[0089] The vehicle control unit 34 does not necessarily need to perform deceleration assistance or lateral avoidance assistance. The vehicle control unit 34 does not necessarily need to change the operating conditions of the collision damage reduction brake between the intersection to be supported and other intersections.

Explanation of Signs

[0090] 1… Support target intersection extraction system, 2, 2A~2Z… Probe vehicles, 2A… Support target vehicle, 10… Server, 11a… Priority road extraction unit, 11b… Risk reduction amount calculation unit, 20… ECU (vehicle support device), 22… External sensor, 32… Shielding determination unit, 33… Support target intersection extraction unit, 34… Vehicle control unit, R1… Priority road (travel road), R1… Travel road (priority road), R2… Non-priority road (intersection road), R2… Intersection road (non-priority road), T… Intersection.

Claims

1. A support target intersection extraction system that extracts a support target intersection that is the target of vehicle support from among intersections included in map information, a priority road extraction unit that extracts a priority road from among roads connected to the intersection based on position information and driving information acquired from a plurality of probe vehicles and the map information, Based on the position information and the driving information acquired from a plurality of the probe vehicles, the average value of the difference between the risk value at the time of a pedestrian jumping out from a non-priority road of the intersection in the risk avoidance behavior actually taken by a plurality of the probe vehicles traveling on the priority road side of the intersection where the priority road has been extracted and the risk value at the time of a pedestrian jumping out from a non-priority road of the intersection assuming that the probe vehicle did not take the risk avoidance behavior, a risk reduction amount calculation unit that calculates the risk reduction amount, a shielding determination unit that determines whether or not an intersecting road that intersects the driving road of the support target vehicle at the intersection is shielded as viewed from the driving road based on the detection result of an external sensor of the support target vehicle; Among the intersections where the driving road of the support target vehicle is the priority road and the risk reduction amount is less than the risk reduction amount threshold, a support target intersection extraction unit that extracts the support target intersection from among the intersections determined to be shielded as viewed from the driving road, comprising, The vehicle support is deceleration support for the support target vehicle, a support target intersection extraction system.

2. A vehicle support device that executes vehicle support for the support target vehicle at the support target intersection extracted by the support target intersection extraction system according to Claim 1, comprising a vehicle control unit that executes a collision damage reduction brake as the vehicle support based on the detection result of an external sensor of the support target vehicle, The vehicle control unit relaxes the operating conditions of the collision damage reduction brake at the support target intersection compared to the operating conditions at other intersections, a vehicle support device.

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