Vehicle control system and collision avoidance support device

Abstract

To provide a vehicle control system that can reduce risk of collision when one has no choice but entering the opposite lane or vehicles from opposite direction may enter the lane of this side due to un-usability of the opposite lane.SOLUTION: A vehicle control system 10 makes it easier to activate collision avoidance assistance by the PCS when a vehicle 2 enters and travels in the opposite lane 102 adjacent to the own lane 101, than when it travels in the own lane 101. In addition, the vehicle control system 10 makes it easier to activate collision avoidance assistance by the PCS when an opposite vehicle may enter and travel in the own lane 101, than when the vehicle is traveling in the opposite lane 102.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle control system having a collision avoidance assistance function and a collision avoidance assistance device. [Background technology]

[0002] Various technologies have been proposed for the purpose of avoiding collisions between a vehicle and an obstacle. For example, Patent Document 1 discloses a technology related to vehicle control when there is a risk on both sides in front of the host vehicle. According to the conventional technology disclosed in Patent Document 1, when a host vehicle is traveling on a straight road and detects an oncoming vehicle approaching from the right front and a parked vehicle in front of the left, a first risk level of the host vehicle colliding with the parked vehicle and a second risk level of the host vehicle colliding with the oncoming vehicle are calculated. Then, a first control threshold is set to the left of the host vehicle based on the first risk level, and a second control threshold is set to the right of the host vehicle based on the second risk level, and an actuator is controlled so that the host vehicle travels between the two control thresholds.

[0003] However, the conventional technology described in Patent Document 1 is a technology that targets a specific situation where there are risks on both sides in front of the vehicle, and does not address the situation targeted by the present disclosure. In addition to Patent Document 1, the following Patent Documents 2 to 4 can be cited as prior art documents that show the technical level in the technical field to which the present disclosure pertains. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-070069 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-137385 [Patent Document 3] Japanese Patent Application Publication No. 2019-043405 [Patent Document 4] Japanese Patent Application Laid-Open No. 2017-224163 Summary of the Invention [Problem to be solved by the invention]

[0005] This disclosure deals with a situation in which a vehicle is traveling in an area where either the vehicle's own lane or an adjacent oncoming lane is impassable. If the vehicle's own lane is impassable, the vehicle is forced to enter the oncoming lane. Furthermore, if the oncoming lane adjacent to the vehicle's own lane is impassable, an oncoming vehicle may enter the vehicle's own lane. In such a situation, the risk of a collision between the vehicle and the oncoming vehicle increases.

[0006] The present disclosure has been made in consideration of the above-mentioned problems. That is, a first object of the present disclosure is to provide a vehicle control system that can reduce the risk of collision with an oncoming vehicle when the host vehicle is forced to enter an oncoming lane or when the oncoming lane is not accessible and there is a possibility that the oncoming vehicle will enter the host vehicle's lane. Also, a second object of the present disclosure is to provide a collision avoidance assistance device that can reduce the risk of collision with an oncoming vehicle when the host vehicle is forced to enter an oncoming lane or when the oncoming lane is not accessible and there is a possibility that the oncoming vehicle will enter the host vehicle's lane. [Means for solving the problem]

[0007] A first vehicle control system according to the present disclosure includes at least one processor and at least one memory storing a program and information to be loaded into the at least one processor. The at least one processor performs autonomous driving, which automatically drives a host vehicle based on necessary driving information, including map information and information about the host vehicle's surrounding environment. In addition to the autonomous driving, the at least one processor also performs collision avoidance assistance, which operates the host vehicle to avoid a collision when the risk of a collision between the host vehicle and an obstacle ahead exceeds a threshold. When the host vehicle is autonomously driving through an area where either the host vehicle's lane or an adjacent oncoming lane is impassable, the at least one processor lowers the threshold at which the collision avoidance assistance activates. This processing facilitates activation of the collision avoidance assistance, thereby reducing the risk of a collision with an oncoming vehicle, when the host vehicle is forced to enter an oncoming lane due to impassable traffic in the host vehicle's lane. Furthermore, even when the oncoming lane is impassable due to the possibility of an oncoming vehicle entering the host vehicle's lane, the collision avoidance assistance can be facilitated to reduce the risk of a collision with an oncoming vehicle.

[0008] In a first vehicle control system according to the present disclosure, at least one processor may cause the host vehicle to travel along a target trajectory determined based on necessary information for autonomous driving. If the host vehicle's lane is impassable and the target trajectory strays into an oncoming lane, the at least one processor may lower a threshold for activating a collision avoidance assist. When the positional relationship between the target trajectory and the oncoming lane increases the risk of a collision, activating the collision avoidance assist can reduce the risk of a collision with an oncoming vehicle.

[0009] In the first vehicle control system according to the present disclosure, at least one processor may temporarily stop the host vehicle before the host vehicle enters the area during autonomous driving. Then, when or after the host vehicle restarts after temporarily stopping, the at least one processor may lower a threshold at which collision avoidance assistance is activated. By lowering the activation threshold of the collision avoidance assistance in conjunction with temporarily stopping the vehicle, it is possible to reduce the risk of a collision.

[0010] In a first vehicle control system according to the present disclosure, at least one processor may perform autonomous driving in accordance with a stop instruction and a start instruction when a stop instruction and a start instruction are issued by a traffic light or a traffic attendant. When a stop instruction and a start instruction are issued by a traffic light or a traffic attendant, at least one processor may maintain or reduce the threshold at which collision avoidance assistance is activated. If a stop instruction and a start instruction are issued by a traffic light or a traffic attendant, the vehicle is unlikely to encounter an oncoming vehicle when traveling through the area. In such a case, maintaining or reducing the activation threshold of the collision avoidance assistance can reduce unnecessary activation of the collision avoidance assistance due to erroneous detection.

[0011] A second vehicle control system according to the present disclosure includes at least one processor and at least one memory storing programs and information to be loaded into the at least one processor. The at least one processor performs autonomous driving, causing the host vehicle to travel along a target trajectory determined based on necessary driving information, including map information and information about the vehicle's surrounding environment. In addition to the autonomous driving, the at least one processor also performs collision avoidance assistance, which operates the host vehicle to avoid a collision when a collision risk between the host vehicle and an obstacle ahead exceeds a threshold. If the target trajectory deviates into an oncoming lane, the at least one processor lowers the threshold at which the collision avoidance assistance activates. This processing facilitates activation of the collision avoidance assistance, thereby reducing the risk of a collision with an oncoming vehicle, when the target trajectory deviates into an oncoming lane, for example, when the host vehicle deviates into an oncoming lane to overtake a vehicle ahead.

[0012] The collision avoidance assistance device according to the present disclosure is a collision avoidance assistance device that activates when the risk of a collision between the host vehicle and an obstacle ahead exceeds a threshold. The collision avoidance assistance device according to the present disclosure lowers a threshold that triggers activation when the host vehicle is traveling in an area where either the host vehicle's own lane or an oncoming lane adjacent to the host vehicle is impassable. By performing such processing, when the host vehicle is forced to enter the oncoming lane due to the oncoming lane being impassable, the collision avoidance assistance device is more likely to activate, thereby reducing the risk of a collision with an oncoming vehicle. Furthermore, when the oncoming lane is impassable and there is a possibility that an oncoming vehicle will enter the host vehicle's lane, the collision avoidance assistance device is more likely to activate, thereby reducing the risk of a collision with an oncoming vehicle. [Effects of the Invention]

[0013] According to the present disclosure, in cases where the vehicle is unable to travel in its own lane and is forced to enter the oncoming lane, or in cases where the oncoming lane is unable to travel and there is a possibility that an oncoming vehicle will enter the vehicle's own lane, collision avoidance assistance can be more easily activated, thereby reducing the risk of collision with an oncoming vehicle. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a diagram illustrating an overview of vehicle control in a one-way traffic area according to an embodiment of the present invention. FIG. [Figure 2] 1 is a diagram illustrating an overview of vehicle control in a one-way traffic area according to an embodiment of the present invention. FIG. [Figure 3] 1 is a diagram illustrating an overview of vehicle control in a one-way traffic area according to an embodiment of the present invention. FIG. [Figure 4] 1 is a block diagram showing a configuration of a vehicle control system according to an embodiment of the present invention; [Figure 5] 4 is a flowchart of vehicle control according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, when the numbers, quantities, amounts, ranges, etc. of each element are mentioned in the following embodiments, the present invention is not limited to the mentioned numbers unless otherwise specified or clearly specified in principle. Furthermore, the structures, etc. described in the following embodiments are not necessarily essential to the present invention unless otherwise specified or clearly specified in principle.

[0016] 1. Overview of the vehicle control system according to this embodiment 1-1.Autonomous driving and collision avoidance assistance The vehicle control system according to this embodiment is a vehicle control system configured to be able to perform automatic driving, which drives a vehicle automatically, and collision avoidance assistance, which assists in avoiding a collision between the vehicle and an obstacle.

[0017] Autonomous driving is performed based on necessary driving information, including map information and information about the vehicle's surrounding environment. Specifically, the optimal route to the destination is determined based on the map information. Then, a driving plan is created to drive the vehicle safely along the optimal route while complying with traffic rules. The driving plan includes operations such as maintaining the current driving lane and changing lanes.

[0018] In autonomous driving, a target trajectory is generated based on a driving plan. The target trajectory is the final driving trajectory that the vehicle should take, and is determined after taking into consideration collisions with all obstacles ahead of the vehicle obtained from information about the vehicle's surrounding environment. The target trajectory includes a set of target positions for the vehicle on the road on which the vehicle is traveling and a target speed for each target position. In autonomous driving, to make the vehicle follow the target trajectory, the deviation (lateral deviation, yaw angle deviation, speed deviation, etc.) between the vehicle and the target trajectory is calculated, and the steering, braking, or driving of the vehicle is controlled to reduce the deviation.

[0019] Collision avoidance assistance is a function that operates the host vehicle to avoid a collision or mitigate damage caused by a collision when it is determined that there is a high possibility of the host vehicle colliding with an obstacle present in front of the host vehicle. An example of collision avoidance assistance is PCS (Pre-Crash Safety). In PCS, automatic braking by a braking actuator is used as a method of collision avoidance. Hereinafter, the collision avoidance assistance according to this embodiment is referred to as PCS.

[0020] The necessity of activating the PCS is determined based on the relative relationship between the host vehicle and an obstacle. In this embodiment, the lateral position of the obstacle relative to the host vehicle and the TTC (Time To Collision) of the obstacle relative to the host vehicle are used for the determination. Specifically, an obstacle whose lateral position is within a predetermined width is recognized as a target for PCS activation, and the PCS is activated when the TTC of the recognized target obstacle falls below a predetermined limit time.

[0021] The magnitude of the collision risk between the vehicle and an obstacle increases as the lateral position of the obstacle approaches the vehicle and as the TTC of the obstacle decreases. In this embodiment, the collision risk is expressed by a function with the lateral position and TTC as parameters. The PCS is activated when the collision risk exceeds a predetermined threshold. The collision risk threshold (activation threshold) at which the PCS activates is variable. Lowering the PCS activation threshold makes it easier for the PCS to activate for obstacles that are farther away from the vehicle. Lowering the PCS activation threshold includes widening the width of the lateral position of an obstacle that is recognized as a target for PCS activation and lengthening the TTC limit time at which the PCS activates for an obstacle that is recognized as a target for activation.

[0022] 1-2. Overview of vehicle control in one-way traffic areas The vehicle control according to this embodiment is characterized by vehicle control in a one-way traffic area where travel is prohibited in either the own lane or the oncoming lane adjacent to the own lane. In a one-way traffic area, there are patterns where the oncoming lane is passable, and patterns where the own lane is passable. In the former case, a situation occurs where the own vehicle has no choice but to enter the oncoming lane (first situation). In the latter case, a situation occurs where an oncoming vehicle may enter the own lane (second situation).

[0023] FIG. 1 is a diagram illustrating an overview of vehicle control in a first situation. FIG. 2 is a diagram illustrating an overview of vehicle control in a second situation. In each situation, a vehicle 2 is traveling on a two-lane road 100 with an oncoming lane 101 and an oncoming lane 102 separated by a center line 103. The vehicle 2 is an autonomous vehicle equipped with a vehicle control system 10 that can perform autonomous driving and collision avoidance assistance. The vehicle 2 also communicates with a remote monitoring center 4 and is a remote assistance vehicle that operates based on remote assistance received from the remote monitoring center 4.

[0024] In the first situation shown in FIG. 1 , an obstacle 110 is present ahead in the vehicle's lane 101. The obstacle 110 blocks the vehicle's lane 101, making it impossible to travel in the lane 101. For this reason, in order for the vehicle 2 to move forward, the vehicle 2 must first enter the oncoming lane 102 to bypass the obstacle 110. Examples of the obstacle 110 blocking the lane in this example include a construction site and a large parked vehicle such as a truck or bus. These obstacles 110 are comprehensively detected by an external sensor mounted on the vehicle 2, or are obtained from a road traffic information and communication system. The road traffic information and communication system provides vehicles with road traffic information via beacons installed on the road or FM multiplex broadcasting.

[0025] In a first situation, the vehicle control system 10 causes the vehicle 2 to temporarily stop in front of the obstacle 110. The stopping position L10 of the vehicle 2 is determined by the distance to the obstacle 110. After the temporary stop, the vehicle control system 10 requests a start instruction from the remote monitoring center 4. When the vehicle control system 10 requests remote assistance from the remote monitoring center 4, it transmits an image of the surroundings of the vehicle 2 captured by a camera of the vehicle 2 to the remote monitoring center 4. The remote operator at the remote monitoring center 4 checks the situation around the vehicle 2 from the camera image displayed on a display in the remote monitoring center 4. Then, if it is determined that there is no problem, the remote operator transmits a start instruction to the vehicle control system 10.

[0026] Upon receiving the start command, the vehicle control system 10 starts the vehicle 2 and generates a target trajectory TR that temporarily passes through the oncoming lane 102 to detour around the obstacle 110. The target trajectory TR is generated so that the distance that the vehicle 2 passes through the oncoming lane 102 is as short as possible and so that the vehicle 2 can safely return to the own lane 101. The vehicle 2 travels along the target trajectory TR, crosses the center line 103, and enters the oncoming lane 102. Then, after passing the obstacle 110, the vehicle 2 crosses the center line 103 again and returns to the own lane 101.

[0027] The risk of a collision with an oncoming vehicle increases from the time the vehicle 2 crosses the center line 103 into the oncoming lane 102 until it returns to the own lane 101, that is, while the vehicle 2 is traveling in the oncoming lane 102. Therefore, the vehicle control system 10 lowers the PCS activation threshold from its normal value at position L11 where the vehicle 2 crosses the center line 103 and enters the oncoming lane 102. Specifically, position L11 where the PCS activation threshold is lowered can be the position where the target trajectory TR intersects with the center line 103. Then, at position L12 where the vehicle 2 returns from the oncoming lane 102 to the own lane 101, the vehicle control system 10 returns the PCS activation threshold to its original value. Specifically, position L12 where the PCS activation threshold is returned to its original value can be the position where the target trajectory TR intersects with the center line 103 again.

[0028] As described above, in the first situation, while the vehicle 2 is in the oncoming lane 102, the vehicle control system 10 temporarily lowers the PCS activation threshold. This makes it easier to activate the PCS, reducing the risk of a collision with an oncoming vehicle. Note that it is conceivable that an oncoming vehicle may appear while the vehicle is traveling around the obstacle 110, causing the PCS to activate. When the vehicle 2 stops due to activation of the PCS, for example, the vehicle 2 may reverse autonomously, or a remote operator may remotely operate the vehicle 2 to reverse.

[0029] 2, an obstacle 110 exists in the oncoming lane 102. The oncoming lane 102 is blocked by the obstacle 110, making it impossible for vehicles to travel in the oncoming lane 102. As a result, an oncoming vehicle 111 traveling in the oncoming lane 102 is forced to temporarily enter the own lane 101 to bypass the obstacle 110.

[0030] In the second situation, the vehicle 2 traveling in the own lane 101 has priority over the oncoming vehicle 111, so it is highly likely that the vehicle traveling in the own lane 101 will not anticipate the preceding vehicle stopping temporarily. If the vehicle 2 is forced to stop temporarily, the distance between the vehicle 2 and the following vehicle may become too close, which may adversely affect the driving of the following vehicle. For this reason, in the second situation, the vehicle control system 10 allows the vehicle 2 to pass by the obstacle 110 without stopping temporarily.

[0031] However, while the vehicle 2 is passing by the obstacle 110, there is a possibility that an oncoming vehicle 111 may appear entering the own lane 101 from the oncoming lane 102. Therefore, the vehicle control system 10 temporarily lowers the PCS activation threshold below the normal value when the vehicle 2 passes by the obstacle 110. Specifically, from the trajectory tr of the oncoming vehicle 111 predicted from the position and size of the obstacle 110, a position L22 where the oncoming vehicle 111 crosses the center line 103 and enters the own lane 101, and a position L21 where the oncoming vehicle 111 returns from the own lane 101 to the oncoming lane 102 are predicted. Then, the section including at least the position L21 to position L22 is determined as the section where the PCS activation threshold is to be lowered.

[0032] As described above, in the second situation, the vehicle control system 10 allows the vehicle 2 to pass by the obstacle 110 without stopping while temporarily lowering the PCS activation threshold. This makes it easier to activate the PCS even when an oncoming vehicle 111 appears in the vehicle's own lane 101, thereby reducing the risk of a collision with the oncoming vehicle 111. Note that it is conceivable that the oncoming vehicle 111 may appear while the vehicle is passing by the obstacle 110, causing the PCS to activate. When the vehicle 2 stops due to activation of the PCS, for example, the vehicle 2 may wait for the oncoming vehicle 111 to back up before moving forward autonomously, or a remote operator may move the vehicle 2 forward while monitoring the oncoming vehicle 111's backing up.

[0033] FIG. 3 shows a third situation that is the target of vehicle control according to this embodiment. In the third situation, as in the first situation, an obstacle 110 located ahead of the vehicle's own lane 101 creates a one-way traffic area in which only the oncoming lane 102 is passable. Therefore, in order for the vehicle 2 to move forward, the vehicle 2 must first enter the oncoming lane 102 to bypass the obstacle 110. However, in the third situation, traffic lights 121 and 122 are installed ahead and behind the obstacle 110. The traffic light 121 ahead of the obstacle 110 as viewed from the vehicle 2 is used to check the safety of the vehicle 2 passing through the own lane 101, and the traffic light 122 behind the obstacle 110 as viewed from the vehicle 2 is used to check the safety of an oncoming vehicle 111 passing through the oncoming lane 102. Specifically, the obstacle 110 in the third situation is a construction site.

[0034] In the third situation, the vehicle control system 10 recognizes a traffic light 121 that is present in the forward detection range SA using an external sensor mounted on the vehicle 2. Then, by image recognition of the camera image, the vehicle control system 10 determines whether the traffic light 121 is red or green. If the traffic light is green, the vehicle control system 10 allows the vehicle 2 to pass through. If the traffic light is red, the vehicle control system 10 makes the vehicle 2 stop temporarily, and allows the vehicle 2 to start moving when the traffic light turns green.

[0035] In the third situation, just as vehicle 2 obeys traffic light 121, oncoming vehicle 111 also obeys traffic light 122. While vehicle 2 is traveling in the oncoming lane 102, traffic light 122 is red, so oncoming vehicle 111 is stopped behind obstacle 110. Therefore, in the third situation, vehicle 2 is unlikely to encounter oncoming vehicle 111 while traveling in the oncoming lane 102. Therefore, vehicle control system 10 maintains the PCS activation threshold at a normal value, rather than lowering the PCS activation threshold as in the first situation.

[0036] The vehicle control in the third situation also applies to the case in the second situation where traffic lights are installed before and after the obstacle 110 in the oncoming lane 102. In this case, just as the vehicle 2 obeys the traffic lights, the oncoming vehicle 111 also obeys the traffic lights. Therefore, instead of lowering the PCS activation threshold as in the second situation, the PCS activation threshold is maintained at a normal value.

[0037] As described above, the vehicle control system 10 maintains the PCS activation threshold at a normal value when traffic lights 121, 122 issue stop and start commands. Lowering the PCS activation threshold increases the PCS activation sensitivity, but also increases the likelihood of the PCS being activated unnecessarily due to false detection. In the first and second situations, reducing the risk of a collision with an oncoming vehicle is given priority, so the PCS activation threshold is lowered. However, in the third situation, the risk of a collision with an oncoming vehicle is not as high as in the first and second situations. Therefore, the PCS activation threshold can be maintained, thereby reducing the likelihood of the PCS being activated unnecessarily due to false detection.

[0038] 2. Configuration and Function of Vehicle Control System According to This Embodiment 2-1. Vehicle control system configuration 4 is a diagram showing an example configuration of a vehicle control system 10 according to this embodiment and a vehicle 2 to which the same is applied. The vehicle 2 includes the vehicle control system 10, an on-board sensor 20 that inputs information to the vehicle control system 10, and a vehicle actuator 30 that operates in response to a signal output from the vehicle control system 10. The vehicle 2 also includes a communication device 40 that can connect to a communication network 6 via mobile communication such as 4G or 5G. The vehicle control system 10 communicates with a remote monitoring center 4 via the communication device 40. The vehicle control system 10, the on-board sensor 20, the vehicle actuator 30, and the communication device 40 are connected via an in-vehicle network.

[0039] The on-board sensors 20 include an external sensor 21, an internal sensor 22, and a GPS receiver sensor 23. The external sensor 21 is a sensor that acquires information about the environment surrounding the vehicle 2. The external sensor 21 includes a camera, a millimeter-wave radar, and a LiDAR. Based on the information acquired by the external sensor 21, processing such as detection of objects present around the vehicle 2, measurement of the relative position and relative speed of the detected object with respect to the vehicle 2, and recognition of the shape of the detected object is performed. The internal sensor 22 is a sensor that acquires information about the movement of the vehicle 2. The internal sensor 22 includes, for example, a wheel speed sensor, an acceleration sensor, a yaw rate sensor, and a steering angle sensor. The GPS receiver 23 is used to acquire information about the current position of the vehicle 2. In addition to these, the vehicle 2 is also equipped with a receiver that receives information from a road traffic information and communication system.

[0040] The vehicle actuators 30 include a steering actuator 31 that steers the vehicle 2, a drive actuator 32 that drives the vehicle 2, and a braking actuator 33 that brakes the vehicle 2. The steering actuator 31 includes, for example, a power steering system, a steer-by-wire steering system, and a rear-wheel steering system. The drive actuator 32 includes, for example, an engine, an EV system, and a hybrid system. The braking actuator 33 includes, for example, a hydraulic brake and a regenerative brake.

[0041] The vehicle control system 10 includes an automatic driving device 11 and a collision avoidance assistance device 12. As described above, the collision avoidance assistance device 12 according to this embodiment is a PCS. The automatic driving device 11 and the collision avoidance assistance device 12 are each an independent ECU (Electronic Control Unit). The automatic driving device 11 and the collision avoidance assistance device 12 include processors 11a and 12a and memories 11b and 12b, respectively. Various programs and data are stored in the memories 11b and 12b. The memories 11b and 12b may include not only memories in the narrow sense such as RAM (Random Access Memory), but also data storage devices such as magnetic disks such as HDDs, optical disks such as DVDs, and flash memory storage devices such as SSDs. Necessary information is input and output between the automatic driving device 11 and the collision avoidance assistance device 12, for example, via CAN communication.

[0042] The automatic driving device 11 is responsible for managing the automatic driving of the vehicle 2, one of the functions of the vehicle control system 10. The memory 11b included in the automatic driving device 11 stores an automatic driving program executable by the processor 11a and various information related to the program. The information includes map information. This map information may be stored in advance in the memory 11b, downloaded from an external server via the communication network 6, or referenced from the map information on the external server. When the automatic driving program is executed by the processor 11a, the processor 11a acquires sensor information from the external sensor 21, recognizes the position of the vehicle 2 on the map, and recognizes the situation around the vehicle 2. The processor 11a creates a driving plan for the vehicle 2 during automatic driving based on the position of the vehicle 2 on the map and the situation around the vehicle 2. Furthermore, the processor 11a generates a target trajectory based on the driving plan and operates the vehicle actuator 30 so that the vehicle 2 follows the target trajectory.

[0043] The collision avoidance assist device 12 is responsible for managing the operation of the PCS, one of the functions of the vehicle control system 10. A collision avoidance assist program executable by the processor 12a and various information related to the program are stored in the memory 12b of the collision avoidance assist device 12. When the collision avoidance assist program is executed by the processor 12a, the processor 11a detects an obstacle ahead of the vehicle 2 using the external sensor 21 and calculates the risk of collision with the obstacle based on information obtained from the external sensor 21 and the internal sensor 22. If the collision risk exceeds the PCS activation threshold, the processor 11a activates the PCS and attempts to avoid a collision with the obstacle by automatic braking using the brake actuator 33. Furthermore, as described with reference to FIGS. 1 to 3, when the vehicle 2 is traveling in an area where either the current lane or the oncoming lane is prohibited, the processor 11a changes the PCS activation threshold depending on the situation in which the vehicle 2 is located.

[0044] 2-2. Vehicle control procedures by the vehicle control system Next, the vehicle control procedure by the vehicle control system 10, particularly the vehicle control procedure when there is a one-way traffic area ahead of the vehicle 2, will be described with reference to the flowchart shown in FIG.

[0045] First, the vehicle control system 10 determines whether or not there is a one-way traffic area ahead of the vehicle 2, based on information acquired from the external sensor 21 and the road traffic information and communication system. If there is no one-way traffic area ahead of the vehicle 2, the vehicle control system 10 skips all the processing in this flowchart and maintains the PCS activation threshold at a normal value (step S101).

[0046] If there is a one-way traffic area ahead of the vehicle 2, the vehicle control system 10 determines whether a traffic light is available before the one-way traffic area based on information obtained by the external sensor 21 (step S102). If a traffic light is available, the vehicle control system 10 determines whether the traffic light is green or red based on the camera image (step S111). If the traffic light is red, the vehicle control system 10 causes the vehicle 2 to temporarily stop in front of the traffic light (step S112).

[0047] If the traffic light is green, the vehicle control system 10 allows the vehicle 2 to pass through without stopping. If the traffic light turns green while the vehicle 2 is stopped, the vehicle control system 10 allows the vehicle 2 to start moving (step S113). If a traffic light is available in the one-way traffic area, not only the vehicle 2 but also oncoming vehicles follow the traffic light. Therefore, the vehicle control system 10 maintains the PCS activation threshold at the normal threshold while the vehicle 2 is passing through the one-way traffic area (step S114).

[0048] If no traffic lights are provided in the one-way traffic area, the vehicle control system 10 determines whether travel is prohibited in the own lane or the oncoming lane (step S103). If travel is prohibited in the oncoming lane, the own lane becomes the priority lane, and the vehicle control system 10 allows the vehicle 2 to pass through the one-way traffic area without temporarily stopping (step S115).

[0049] Vehicle 2 passes through a one-way traffic area while traveling in its own lane, but there is a possibility that an oncoming vehicle will appear in its own lane from the oncoming lane. Therefore, vehicle control system 10 lowers the PCS activation threshold below the normal threshold (step S108). The PCS activation threshold remains lowered until vehicle 2 passes through the one-way traffic area (step S109). Then, after vehicle 2 passes through the one-way traffic area, vehicle control system 10 returns the PCS activation threshold to the normal value (step S110).

[0050] If there is no traffic light in the one-way traffic area and travel is prohibited on the side of the vehicle's own lane, the vehicle control system 10 causes the vehicle 2 to temporarily stop before the one-way traffic area (step S104). Next, the vehicle control system 10 communicates with the remote monitoring center 4 using the communication device 40, transmits camera images of the surroundings of the vehicle 2 to the remote monitoring center 4, and requests a start instruction from the remote monitoring center 4 (step S105). The vehicle control system 10 continues to temporarily stop the vehicle 2 until a transmission instruction is issued from the remote monitoring center 4 (step S106). Then, when a transmission instruction is issued from the remote monitoring center 4, the vehicle control system 10 causes the vehicle 2 to start (step S107).

[0051] Although the situation of the oncoming lane has been confirmed by the remote operator at the remote monitoring center 4, there is a possibility that an oncoming vehicle will appear in front of vehicle 2 after the vehicle enters the oncoming lane. Therefore, vehicle control system 10 lowers the PCS activation threshold below the normal threshold (step S108). The PCS activation threshold remains lowered until vehicle 2 passes through the one-way traffic area (step S109). Then, after vehicle 2 passes through the one-way traffic area and returns to its own lane, vehicle control system 10 returns the PCS activation threshold to the normal value (step S110).

[0052] Vehicle control according to the above procedure makes it easier to activate the PCS when the vehicle 2 is forced to enter the oncoming lane because the vehicle's own lane is closed, or when the oncoming lane is closed and there is a possibility that an oncoming vehicle will enter the vehicle's own lane. This reduces the risk of a collision with an oncoming vehicle in a one-way traffic area. Furthermore, if a traffic light is installed in the one-way traffic area, the vehicle is less likely to encounter an oncoming vehicle when traveling through the one-way traffic area. In such cases, the PCS activation threshold is maintained, thereby reducing unnecessary activation of the PCS due to erroneous detection.

[0053] 3. Other embodiments In the first situation shown in FIG. 1, if the external sensor 21 does not detect an oncoming vehicle in the opposite lane, the PCS activation threshold may be lowered below normal and the vehicle may pass through the one-way traffic area without stopping. In the third situation shown in FIG. 3, the PCS activation threshold may be lowered rather than maintained, but the amount of reduction may be smaller than the reduction in the activation threshold in the first and second situations. In the third situation shown in FIG. 3, if a traffic guide is present instead of a traffic light, the vehicle may stop and start in accordance with the actions of the guide. In this case, the actions of the guide and the instructions are associated in advance.

[0054] Examples of vehicle 2 entering the oncoming lane are not limited to cases where vehicle 2 is forced to enter the oncoming lane because the vehicle's own lane is impassable. For example, vehicle 2 may enter the oncoming lane to overtake a leading vehicle. In such cases, as in the first situation, the PCS activation threshold can be lowered below the normal value to make the PCS more likely to activate and reduce the risk of a collision with an oncoming vehicle. Therefore, vehicle control system 10 may lower the PCS activation threshold when the target trajectory determined based on necessary driving information, including map information and information about the vehicle's surrounding environment, crosses the center line and strays into the oncoming lane.

[0055] In the above embodiment, a PCS that avoids a collision by braking is given as an example of collision avoidance assistance, but collision avoidance assistance by steering, or collision avoidance assistance by both braking and steering, is also possible. For example, collision avoidance assistance by steering is effective when an oncoming vehicle is discovered the moment the vehicle is about to cross the center line into the oncoming lane and the vehicle returns to the original lane, or when the oncoming lane is sufficiently wide, including the shoulder. Furthermore, a collision with an oncoming vehicle can be avoided by steering toward the vehicle's lane even in a section from which the vehicle passes an obstacle such as a construction site before returning to the vehicle's lane.

[0056] In the above embodiment, the collision avoidance assistance function is implemented in an ECU separate from the automatic driving device 11, but the collision avoidance assistance function can also be incorporated into the automatic driving device 11. That is, a collision avoidance assistance program executable by the processor 11a and various pieces of information related to the program may be stored in the memory 11b of the automatic driving device 11. That is, the collision avoidance assistance function may be realized as a single application.

[0057] Furthermore, the collision avoidance assistance device according to the present disclosure can be applied not only to autonomously driven vehicles such as the vehicle 2 of the above embodiment, but also to manually driven vehicles that are driven by the operation of a driver. [Explanation of symbols]

[0058] 2 vehicles 4 Remote Monitoring Center 6. Communication Networks 10 Vehicle Control System 11 Automatic driving device 11a processor 11b memory 12 Collision avoidance support device 12a processor 12b memory 20 In-vehicle sensors 21 External Sensor 30 Vehicle Actuator 40 Communication equipment 101 own lane 102 Oncoming traffic 103 Center Line 110 Obstacles 111 Oncoming vehicle 121,122 Traffic lights TR target trajectory

Claims

1. A vehicle control system capable of performing collision avoidance assistance to operate a vehicle so as to avoid a collision with an obstacle ahead, at least one processor; at least one memory in which programs and information to be loaded into the at least one processor are stored; The at least one processor is configured to more easily activate the collision avoidance assistance when the vehicle is traveling in an oncoming lane adjacent to the own lane than when the vehicle is traveling within the own lane. A vehicle control system comprising:

2. A vehicle control system capable of performing collision avoidance assistance to operate a vehicle so as to avoid a collision with an obstacle ahead, at least one processor; at least one memory in which programs and information to be loaded into the at least one processor are stored; the at least one processor is more likely to activate the collision avoidance assistance when an oncoming lane adjacent to the host vehicle lane is blocked by an obstacle than when the oncoming lane is not blocked by an obstacle; When a stop instruction or a start instruction is given by a traffic light or a traffic guide, the collision avoidance support is made less likely to be activated than when the stop instruction or the start instruction is not given, or the ease of activation of the collision avoidance support is maintained. A vehicle control system comprising:

3. 2. The vehicle control system according to claim 1, The at least one processor, if the vehicle is stopped before entering the oncoming lane, starts facilitating activation of the collision avoidance assistance when or after the vehicle restarts after the stop. A vehicle control system comprising:

4. In the vehicle control system according to claim 1 or 3, When a stop instruction and a start instruction are given by a traffic light or a traffic guide, the at least one processor suppresses the likelihood of activating the collision avoidance assistance compared to when the stop instruction and the start instruction are not given, or maintains the likelihood of activating the collision avoidance assistance. A vehicle control system comprising:

5. 4. The vehicle control system according to claim 1, the vehicle control system is a system capable of executing automatic driving of the vehicle, The at least one processor is configured to more easily activate the collision avoidance assistance when the vehicle enters the oncoming lane during the automated driving than when the vehicle is traveling within the own lane. A vehicle control system comprising:

6. 6. The vehicle control system according to claim 5, The at least one processor drives the vehicle along a target trajectory during the automated driving, and makes it easier to activate the collision avoidance assistance when the target trajectory strays from the own vehicle lane into the oncoming lane. A vehicle control system comprising:

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