Vehicle driving support device

Abstract

To provide a vehicle driving support device for reducing the risk of an accident with another vehicle by reasonable collision damage mitigation brake control when an own vehicle turns across an opposite lane at an intersection or the like.SOLUTION: A collision avoidance control section 20 of a vehicle driving support device 1 comprises: an own-vehicle position estimation section 21; an oncoming vehicle recognition section 22; and a collision avoidance operation determination section 24 for determining whether to execute collision avoidance control in which a travel control unit 10 operates a brake drive section 7, for a collision predicted position Pn at which a collision of an own vehicle M with an oncoming vehicle V is predicted by a collision prediction calculation section 23. The collision avoidance control section 20 causes the collision avoidance control to intervene such that kinetic energy in a travel direction remains in the own vehicle M, at collision avoidance positions Pa and Pb on an own-vehicle predicted travel path, each corresponding to the collision predicted position Pn for which the collision avoidance control is to be executed by the collision avoidance operation determination section 24.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a driving assistance device for a vehicle equipped with a collision mitigation brake. [Background technology]

[0002] 2. Description of the Related Art In recent years, many vehicles are equipped with an autonomous emergency braking (AEB) system as one of driving assistance devices.

[0003] The collision damage mitigation brake control warns the driver and also forcibly intervenes in brake control when it is determined that the vehicle is likely to collide (including interference) with another vehicle, obstacle, etc. In this way, the collision damage mitigation brake control is intended to prevent the vehicle from colliding with another vehicle, obstacle, etc.

[0004] A driving assistance device of a vehicle executes collision damage mitigation brake control when it determines that there is a possibility of a collision between the vehicle and another vehicle such as a preceding vehicle, an oncoming vehicle, a crossing vehicle, etc. Such collision damage mitigation brake control is disclosed in, for example, Patent Document 1. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2021-191660 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, when a vehicle turns around and crosses the oncoming lane at an intersection (for example, turning right at an intersection in a left-hand traffic area such as Japan), there are often multiple oncoming vehicles approaching the intersection. In this case, the vehicle's automatic emergency brake (AEB) may actually increase the risk of an accident.

[0007] For example, if an oncoming vehicle is approaching while the vehicle is turning at an intersection and the automatic emergency braking system (AEB) is activated and the vehicle stops in the intersection, it may take time for the vehicle to start moving again, which could increase the risk of an accident with another vehicle.

[0008] The above problems can be solved if the vehicle and the oncoming vehicle are equipped with functions such as road-to-vehicle communication (Driving Safety Support Systems) and vehicle-to-vehicle communication. However, not all vehicles are equipped with such functions.

[0009] In view of the above circumstances, the present invention aims to provide a vehicle driving assistance device that reduces the risk of accidents with other vehicles by implementing rational collision damage mitigation brake control when the vehicle turns and crosses an oncoming lane at an intersection, etc. [Means for solving the problem]

[0010] A vehicle driving assistance device according to one aspect of the present invention includes a surrounding environment recognition unit that acquires information about a surrounding environment ahead of a vehicle, a cruise control unit that activates a brake drive unit, and a collision avoidance control unit provided in the cruise control unit, the collision avoidance control unit including a vehicle position estimation unit that estimates a position of the vehicle and generates a predicted vehicle path when the vehicle turns and crosses an oncoming lane at an intersection, an oncoming vehicle recognition unit that recognizes oncoming vehicles traveling in each vehicle lane of the oncoming lane based on the surrounding environment information, and a collision prediction unit that generates a collision prediction unit that predicts a collision at a point where the predicted vehicle path and the path of the oncoming vehicle intersect. the collision prediction calculation unit detecting a position of the host vehicle for each vehicle lane and predicting a collision between the host vehicle and the oncoming vehicle; and a collision avoidance operation determination unit determining whether or not the cruise control unit should execute collision avoidance control to operate the brake drive unit for the collision predicted position where a collision between the host vehicle and the oncoming vehicle has been predicted by the collision prediction calculation unit, and the collision avoidance control is intervened at a collision avoidance position on the host vehicle's predicted path of travel corresponding to the collision predicted position where the collision avoidance control is executed by the collision avoidance operation determination unit so as to leave kinetic energy in the traveling direction of the host vehicle. Effect of the Invention

[0011] According to the present invention, it is possible to provide a vehicle driving assistance device that reduces the risk of an accident with another vehicle by implementing rational collision damage mitigation brake control when the vehicle turns and crosses an oncoming lane at an intersection, etc. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a vehicle driving assistance device; [Diagram 2] Flowchart showing an oncoming vehicle collision determination processing routine [Diagram 3] Flowchart showing an AEB intervention determination processing routine [Figure 4] Flowchart showing the AEB execution processing routine [Diagram 5] A diagram showing a predicted target path when the vehicle turns right at an intersection, with an oncoming vehicle traveling in the oncoming lane. [Figure 6] A diagram showing a state in which an oncoming vehicle is detected when the vehicle is turning right at an intersection, and there is a car changing lanes to overtake the oncoming motorcycle in the oncoming lane. [Figure 7] A diagram showing the response of a vehicle when avoiding a collision with an oncoming motorcycle in the first lane at an intersection. [Figure 8] A diagram showing the response of a vehicle when avoiding a collision with an oncoming vehicle in the second lane at an intersection. [Figure 9] A diagram showing the response of a vehicle when restarting and turning right after avoiding a collision with an oncoming motorcycle in the first lane at an intersection. [Figure 10] A diagram showing the response of a vehicle when it is forced to stop just before the predicted collision position with an oncoming motorcycle in the first lane at an intersection. [Figure 11] A diagram showing the response of a vehicle when stopping just before a predicted collision position with an oncoming vehicle in the second lane at an intersection. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of a vehicle driving assistance device according to one aspect of the present invention will be described in detail with reference to the drawings. In the drawings used in the following description, the scales of the components are different so that each component can be recognized on the drawings. Therefore, the present invention is not limited only to the number of components, the shapes of the components, the size ratios of the components, and the relative positional relationships of the components shown in these drawings.

[0014] 1, a vehicle driving assistance device 1 is mounted on a vehicle such as an automobile. The vehicle driving assistance device 1 includes a driving control unit (ECU) 10, a surrounding environment recognition unit 2 as a surrounding environment information acquisition unit, a road map database 5, a brake drive unit 7, and an alarm device 8.

[0015] The cruise control unit 10 executes autonomous emergency braking (AEB) control in addition to well-known adaptive cruise control (ACC) and active lane keep (ALK) control. Note that the ACC control and ALK control executed by the cruise control unit 10 are the same as conventional controls, and therefore detailed description of these controls will be omitted.

[0016] In the AEB control, when it is determined that there is a possibility that the vehicle will collide (including interference) with another vehicle, an obstacle, etc., the warning device 8 is activated to notify the driver. In addition, in the AEB control, when necessary, the brake drive unit 7 is forcibly activated to avoid the vehicle colliding with the other vehicle, the obstacle, etc.

[0017] The other vehicles are a preceding vehicle, an oncoming vehicle, and a crossing vehicle. The preceding vehicle and the oncoming vehicle correspond to vehicles ahead of the host vehicle. An oncoming vehicle is a vehicle traveling in the oncoming lane toward the host vehicle's travel path. A crossing vehicle is a vehicle traveling in the direction of the host vehicle's travel path at an intersection that intersects with the host vehicle's travel path at an intersection.

[0018] The surrounding environment recognition unit 2 includes a surrounding environment sensor 3 and a surrounding environment recognition unit 4. The surrounding environment sensor 3 senses the environment around the vehicle to obtain surrounding environment information. One or more surrounding environment sensors 3 are disposed, for example, at the front, at the front corners, inside the windshield, etc. of the vehicle.

[0019] The surrounding environment sensor 3 is composed of at least one of the following devices: ultrasonic radar, millimeter wave radar, LiDAR (Light Detection and Ranging), a stereo camera consisting of a main camera and a sub camera, a monocular camera, etc. The surrounding environment sensor 3 may be composed of a combination of two or more of these devices.

[0020] The surrounding environment recognition unit 4 recognizes other vehicles (surrounding vehicles) such as automobiles, motorcycles, and bicycles traveling around the vehicle, road signs, road markings, etc., using well-known methods such as pattern matching, based on the surrounding environment information acquired by the surrounding environment sensor 3. The surrounding environment recognition unit 4 then outputs the recognized vehicle information to the cruise control unit 10.

[0021] Furthermore, the road map database 5 is a large-capacity storage medium such as a HDD. Road map information 6 is stored in the road map database 5. This road map information 6 includes static information such as lane data, road data, and road structure data.

[0022] The lane data includes the number of lanes, lane width data, lane center position coordinate data, lane travel azimuth data, speed limit data, etc. The road data includes intersections, priority roads, non-priority roads, etc. The road structure data includes traffic lights, road signs, etc.

[0023] In addition to the surrounding environment recognition unit 4 and road map database 5, the input side of the driving control unit 10 is connected to a GNS (Global Navigation Satellite System) receiver 9 that receives positioning signals transmitted from a plurality of positioning satellites.

[0024] The driving control unit 10 and the surrounding environment recognition unit 4 are configured with a well-known microcomputer equipped with a CPU, RAM, ROM, etc., and its peripheral devices. The ROM stores in advance programs to be executed by the CPU, fixed data such as a base map, and the like.

[0025] The brake driving unit 7 and the warning device 8 are connected to the output side of the driving control unit 10. The brake driving unit 7 supplies brake fluid pressure to wheel cylinders of brake calipers provided on each wheel (not shown) to forcibly operate the brakes of the host vehicle.

[0026] On the other hand, the warning device 8 issues a warning to the driver. The warning device 8 issues the warning to the driver audibly through an audio speaker or visually through a display.

[0027] The cruise control unit 10 also includes a collision avoidance control unit 20 as a function of executing AEB control when another vehicle is detected. The collision avoidance control unit 20 includes a host vehicle position estimation unit 21, an oncoming vehicle recognition unit 22, a collision prediction calculation unit 23, and an AEB operation determination unit 24. The AEB operation determination unit 24 functions as a collision avoidance operation determination unit.

[0028] The vehicle position estimation unit 21 acquires position information (latitude, longitude, altitude) of the vehicle's current position based on the positioning signal received by the GNS receiving unit 9. The vehicle position estimation unit 21 then performs map matching on the road map of the road map information 6 to estimate the current position of the vehicle (vehicle position).

[0029] Furthermore, the vehicle position estimation unit 21 acquires intersection information ahead of the lane (vehicle road) on which the vehicle is traveling, based on the position information of the vehicle, with reference to the road map information 6. Furthermore, the vehicle position estimation unit 21 acquires intersection information ahead of the vehicle road on which the vehicle is traveling, based on the surrounding environment information recognized by the surrounding environment recognition unit 4 of the surrounding environment recognition unit 2.

[0030] Then, the vehicle position estimation unit 21 obtains the time required to reach an intersection, etc. (intersection arrival time) based on the intersection information. The vehicle position estimation unit 21 adds the current time to the obtained intersection arrival time. In this way, the vehicle position estimation unit 21 calculates the time when the vehicle enters the intersection, etc. (intersection entry time).

[0031] Furthermore, the vehicle position estimation unit 21 generates a predicted path of the vehicle when the vehicle turns and crosses an oncoming lane when the vehicle turns at an intersection, etc. The vehicle position estimation unit 21 receives inputs of the vehicle speed, the blinking signal of the turn signal, steering angle information, etc.

[0032] The oncoming vehicle recognition unit 22 recognizes whether or not an oncoming vehicle traveling in the oncoming lane has been detected, based on the vehicle information acquired by the surrounding environment recognition unit 4. In particular, the oncoming vehicle recognition unit 22 recognizes an oncoming vehicle traveling in the oncoming lane toward the intersection when the host vehicle turns and crosses the oncoming lane.

[0033] When an oncoming vehicle traveling toward an intersection on the vehicle's travel path is detected by the oncoming vehicle recognition unit 22, the collision prediction calculation unit 23 calculates the intersection time of the oncoming vehicle with the vehicle's predicted travel path in the intersection. The collision prediction calculation unit 23 then compares the arrival time of the vehicle on the vehicle's predicted travel path with the intersection time of the oncoming vehicle, and calculates whether or not there is a possibility of collision between the vehicle and the oncoming vehicle.

[0034] When the collision prediction calculation unit 23 determines that there is a possibility of a collision between the vehicle and an oncoming vehicle at an intersection or the like, the AEB operation determination unit 24 activates the warning device 8 to notify the driver of the possibility of a collision.

[0035] As a result, the warning device 8 prompts the host vehicle to decelerate. Furthermore, when there is a high possibility that the host vehicle will collide with an oncoming vehicle, the AEB operation determination unit 24 operates the brake drive unit 7. As a result, the host vehicle is forcibly decelerated. As a result, the AEB operation determination unit 24 prevents the host vehicle from colliding with the oncoming vehicle by decelerating or stopping the host vehicle.

[0036] At that time, if a predetermined control intervention release condition is satisfied, the AEB operation determination unit 24 deactivates the brake drive unit 7. As a result, the host vehicle is controlled so that it can pass through the intersection without being forcibly decelerated.

[0037] In the following description, the function executed by the cruise control unit 10 will be described in detail with regard to AEB control for oncoming vehicles traveling in the oncoming lane entering an intersection when the vehicle is turning right or left (hereinafter, turning right) at an intersection and crossing the oncoming lane.

[0038] In the AEB control of the cruise control unit 10, other vehicles to be controlled include a preceding vehicle, a crossing vehicle, etc., but since the AEB control for these preceding vehicles, crossing vehicles, etc. is the same as conventional, a description thereof will be omitted.

[0039] The vehicle driving assistance device 1 executes a process for determining whether or not a vehicle will collide with an oncoming vehicle when turning and crossing an oncoming lane at an intersection, under the control of a collision avoidance control section 20 provided in the cruise control unit 10. Specifically, the process is performed according to an oncoming vehicle collision determination process routine shown in Figs.

[0040] In the following description, a road on which driving on the left side is prescribed in Japan, the UK, etc. will be taken as an example. Therefore, on a road on which driving on the right side is prescribed in the US, etc., the control by the collision avoidance control unit 20 can be applied by replacing the left side with the right side.

[0041] 2, in the oncoming vehicle collision determination process, the collision avoidance control unit 20 estimates the vehicle position (S1). The collision avoidance control unit 20 acquires, by the vehicle position estimation unit 21, position information (latitude, longitude, altitude) of the current position (vehicle position) of the vehicle M (see FIG. 5) while it is traveling, in chronological order, based on the positioning signal received by the GNS receiving unit 9.

[0042] Then, the vehicle position estimation unit 21 performs map matching of the acquired position information on the road map of the road map information 6. The vehicle position estimation unit 21 estimates the current position (vehicle position) of the vehicle M, which changes from moment to moment. At the same time, the vehicle position estimation unit 21 identifies the roadway (vehicle roadway) on which the vehicle M is traveling and the traveling direction.

[0043] Next, the collision avoidance control unit 20 judges whether an intersection is detected ahead (S2). The collision avoidance control unit 20 detects, by the vehicle position estimation unit 21, whether an intersection is present at a predetermined position (several hundred meters) ahead of the current position of the vehicle M on the road on which the vehicle M is traveling, based on the surrounding environment information and road map information.

[0044] If an intersection is detected (step S2: YES), the collision avoidance control unit 20 proceeds to step S3. If an intersection is not detected (step S2: NO), the collision avoidance control unit 20 exits the routine, returns to step S1, and repeats the subsequent processes.

[0045] When the process proceeds to step S3, the collision avoidance control unit 20 determines whether the host vehicle M will turn right at the intersection (S3). The collision avoidance control unit 20 detects whether the host vehicle M will turn right at the intersection based on signal inputs such as a turn signal light operation and a steering operation (not shown).

[0046] The collision avoidance control unit 20 also determines that the host vehicle M will turn right when the host vehicle position specified by the host vehicle position estimation unit 21 is, for example, in a right-turn lane provided just before an intersection. If the host vehicle M does not turn right at the intersection, the collision avoidance control unit 20 exits the routine, returns to step S1, and repeats the subsequent processing. That is, the collision avoidance control unit 20 determines that the host vehicle M will not turn at the intersection and will travel straight along the host vehicle travel path.

[0047] If the collision avoidance control unit 20 determines that the vehicle M will turn right at the intersection (step S3: YES), the process proceeds to step S4. If the collision avoidance control unit 20 determines that the vehicle M will not turn right at the intersection (step S3: NO), the process exits the routine, returns to step S1, and repeats the subsequent processes.

[0048] When the process proceeds to step S4, the collision avoidance control unit 20 determines whether or not there is a traffic light at the intersection (S4). The collision avoidance control unit 20 detects, by the vehicle position estimation unit 21, whether or not there is a traffic light at the intersection, based on the surrounding environment information and the intersection information stored in the road map information.

[0049] If a traffic light is detected (step S4: YES), the collision avoidance control unit 20 proceeds to step S5. If a traffic light is not detected (step S4: NO), the collision avoidance control unit 20 proceeds to step S6.

[0050] When the process proceeds to step S5, the collision avoidance control unit 20 determines whether or not the detected traffic light is a green light (S5). The collision avoidance control unit 20 detects whether or not the traffic light is a green light based on the surrounding environment information.

[0051] If the traffic light is green (step S5: YES), the collision avoidance control unit 20 proceeds to step S6. If the traffic light is not green, such as red (step S5: NO), the collision avoidance control unit 20 exits the routine and returns to step S1, and repeats the subsequent processes.

[0052] In addition, when the arrow signal accompanying the traffic light is green, the collision avoidance control unit 20 exits the routine, returns to step S1, and repeats the subsequent processing since the vehicle M has priority to turn right at the intersection.

[0053] When the process proceeds to step S6, the collision avoidance control unit 20 determines whether or not an oncoming vehicle V (for example, oncoming motorcycle V1, oncoming automobiles V2, V3, etc. as oncoming vehicles shown in FIG. 5) has been detected in the oncoming lane (S6). At this time, the collision avoidance control unit 20 detects, based on the surrounding environment information, by the oncoming vehicle recognition unit 22 whether or not there is an oncoming vehicle V traveling in the oncoming lane toward the intersection.

[0054] Then, if the oncoming vehicle V is detected by the oncoming vehicle recognition unit 22 (step S6: YES), the collision avoidance control unit 20 proceeds to step S7. If the oncoming vehicle V is not detected by the oncoming vehicle recognition unit 22 (step S6: NO), the collision avoidance control unit 20 exits the routine, returns to step S1, and repeats the subsequent processes.

[0055] When the process proceeds to step S7, the collision avoidance control unit 20 sets a predicted vehicle travel path when the vehicle M turns and crosses an oncoming lane (S7). The collision avoidance control unit 20 sets a predicted vehicle travel path when the vehicle M turns and crosses an oncoming lane, here, when turning right at an intersection, as shown by a dashed line in Fig. 5, by the vehicle position estimation unit 21. Note that the setting of the predicted vehicle travel path is the same control as in the past, and therefore a detailed description thereof will be omitted.

[0056] Next, the collision avoidance control unit 20 executes an AEB intervention determination process (S8). This AEB intervention determination process is a subroutine that is executed by the collision avoidance control unit 20 according to the routine of FIG.

[0057] 3, in the AEB intervention determination process, the collision avoidance control unit 20 determines whether or not an oncoming vehicle V is detected in the n-th vehicle lane of the oncoming lane (S11). The collision avoidance control unit 20 detects the oncoming vehicle V in the n-th vehicle lane of the oncoming lane by the oncoming vehicle recognition unit 22 based on the surrounding environment information.

[0058] At this time, the oncoming vehicle recognition unit 22 first detects the oncoming vehicle V in the oncoming lane, starting from the first vehicle lane (n=1) which is the furthest from the host vehicle. That is, the oncoming vehicle recognition unit 22 detects the oncoming vehicle V in the oncoming lane, starting from the nth vehicle lane (n=min). Note that the oncoming vehicle recognition unit 22 may first detect the oncoming vehicle V in the oncoming lane, starting from the nth vehicle lane (n=max) which is the closest to the host vehicle.

[0059] Then, when the oncoming vehicle recognition unit 22 detects an oncoming vehicle V in the nth vehicle lane of the oncoming lane (step S11: YES), the collision avoidance control unit 20 proceeds to step S12. On the other hand, when the oncoming vehicle recognition unit 22 does not detect an oncoming vehicle V in the nth vehicle lane of the oncoming lane (step S11: NO), the collision avoidance control unit 20 proceeds to step S19.

[0060] When the process proceeds to step S12, the collision avoidance control unit 20 judges whether or not there is a vehicle changing lanes ahead of the oncoming vehicle V (S12). When detecting an oncoming vehicle V in the second vehicle lane (n=2), the collision avoidance control unit 20 detects, for example, an oncoming vehicle V3 changing lanes into the second vehicle lane to overtake an oncoming motorcycle V1 traveling in the first vehicle lane, as shown in Fig. 6, by the oncoming vehicle recognition unit 22. The oncoming vehicle recognition unit 22 judges the lane change of the oncoming vehicle V3 by the blinking of a turn signal, for example.

[0061] Then, when the oncoming vehicle recognition unit 22 detects an oncoming vehicle V in the nth vehicle lane of the oncoming lane (step S11: YES), the collision avoidance control unit 20 proceeds to step S12. On the other hand, when the oncoming vehicle recognition unit 22 does not detect an oncoming vehicle V in the nth vehicle lane of the oncoming lane (step S11: NO), the collision avoidance control unit 20 proceeds to step S14.

[0062] When the process proceeds to step S13, the collision avoidance control unit 20 sets the lane-changing vehicle in the n-th vehicle lane as an oncoming vehicle V (S13). For example, as shown in FIG. 6, the collision avoidance control unit 20 sets the oncoming vehicle V3 changing lanes from the first vehicle lane to the second vehicle lane as the oncoming vehicle V by the collision prediction calculation unit 23.

[0063] Next, the collision avoidance control unit 20 calculates the arrival time Tmn at a collision prediction point Pn, which is a predicted position of a collision between the host vehicle M and the oncoming vehicle V on the host vehicle predicted traveling path (S14). The collision avoidance control unit 20 detects the collision prediction point Pn, which intersects with the host vehicle predicted traveling path when the oncoming vehicle V travels straight, by the collision prediction calculation unit 23.

[0064] At this time, the collision prediction calculation unit 23 divides the distance from the host vehicle position to the collision prediction point Pn by the host vehicle speed to obtain the time (arrival time) until the host vehicle M reaches the collision prediction point Pn. Next, the collision prediction calculation unit 23 adds the current time to the arrival time to calculate the arrival time Tmn of the host vehicle M to the collision prediction point Pn.

[0065] The speed of the host vehicle M is detected by a vehicle speed sensor (not shown). The distance to the collision prediction point Pn of the host vehicle M is obtained by measuring the distance to the collision prediction point Pn on the host vehicle's predicted travel path. At this time, the collision avoidance control unit 20 calculates the distance to the collision prediction point Pn by the oncoming vehicle recognition unit 22 based on the surrounding environment information acquired by the surrounding environment recognition unit 4 of the surrounding environment recognition unit 2.

[0066] Next, the collision avoidance control unit 20 calculates the arrival time Tvn of the oncoming vehicle V to the collision prediction point Pn (S15). The collision avoidance control unit 20 detects the position and vehicle speed of the oncoming vehicle V by the oncoming vehicle recognition unit 22. At this time, the oncoming vehicle recognition unit 22 detects the relative distance and relative speed with respect to the host vehicle M from the vehicle information of the oncoming vehicle V input from the surrounding environment recognition unit 4.

[0067] Then, the collision avoidance control unit 20 calculates the distance to the collision prediction point Pn on the predicted path of the oncoming vehicle V and the vehicle speed from the relative distance and relative speed with respect to the host vehicle M. The vehicle speed of the oncoming vehicle V can also be obtained from the amount of movement of the oncoming vehicle V detected in time series.

[0068] Next, the collision avoidance control unit 20 divides the distance to the collision prediction point Pn of the oncoming vehicle V by the vehicle speed to calculate the time (arrival time) until the oncoming vehicle V reaches the collision prediction point Pn by the collision prediction calculation unit 23.

[0069] Then, the collision prediction calculation unit 23 calculates the arrival time at the collision prediction point Pn by adding the current time to the arrival time of the collision prediction point Pn. Next, the collision prediction calculation unit 23 calculates the arrival time Tvn of the oncoming vehicle V at the collision prediction point Pn by adding the current time to the arrival time.

[0070] The collision prediction calculation unit 23 calculates the absolute value |Tmn-Tvn| of the difference between the arrival time Tmn of the host vehicle M to the collision prediction point Pn and the arrival time Tvn of the oncoming vehicle V to the collision prediction point Pn, and compares it with a predetermined threshold value Tnth of the collision judgment time.

[0071] Then, the collision avoidance control unit 20 determines whether the absolute value |Tmn-Tvn| of the difference between the arrival time Tmn of the host vehicle M to the collision predicted point Pn and the arrival time Tvn of the oncoming vehicle V to the collision predicted point Pn is less than or equal to a predetermined threshold Tnth of the collision judgment time (S16).

[0072] The predetermined threshold value Tnth of the collision determination time is a time width during which the host vehicle M and the oncoming vehicle V may collide at the collision prediction point Pn, and is set in advance through experiments, etc. The predetermined threshold value Tnth of the collision determination time is set, for example, based on the deceleration (e.g., 3 m / s) that the driver of the oncoming vehicle V can generally achieve during the reaction time (e.g., 2 seconds) of the driver of the oncoming vehicle V. 2 ) and adding the result.

[0073] Then, if the absolute value of the difference |Tmn-Tvn| calculated by the collision prediction calculation unit 23 is less than or equal to a predetermined threshold value Tnth of the collision judgment time (|Tmn-Tvn|≦Tnth) (step S16: YES), the collision avoidance control unit 20 determines by the AEB operation judgment unit 24 that there is a possibility of a collision between the host vehicle M and the oncoming vehicle V, and proceeds to step S17.

[0074] In addition, if the absolute value of the difference |Tmn-Tvn| calculated by the collision prediction calculation unit 23 is not less than or equal to a predetermined threshold value Tnth for the collision judgment time (|Tmn-Tvn|>Tm2) (step S16: NO), the collision avoidance control unit 20 determines through the AEB operation judgment unit 24 that the host vehicle M and the oncoming vehicle V can pass the collision prediction point Pn without colliding, and proceeds to step S18.

[0075] In other words, if the arrival time Tmn of the host vehicle M at the predicted collision point Pn is greater than the arrival time Tvn of the oncoming vehicle V at the predicted collision point Pn (Tmn>Tvn), and the absolute value of the difference |Tmn-Tvn| exceeds a predetermined threshold Tnth of the collision judgment time (|Tmn-Tvn|>Tm2), the host vehicle M will pass the predicted collision point Pn earlier than the oncoming vehicle V.

[0076] In addition, if the arrival time Tvn of the oncoming vehicle V to the collision predicted point Pn is greater than the arrival time Tmn of the host vehicle M to the collision predicted point Pn (Tvn>Tmn), and the absolute value of the difference |Tmn-Tvn| exceeds a predetermined threshold Tnth of the collision judgment time (|Tmn-Tvn|>Tm2), the oncoming vehicle V passes the collision predicted point Pn earlier than the host vehicle M.

[0077] By satisfying these conditions, the host vehicle M can pass through the predicted collision point Pn without colliding with the oncoming vehicle V.

[0078] When the collision avoidance control unit 20 determines that the AEB operation determination unit 24 will collide with the oncoming vehicle V (step S16: YES), the collision avoidance control unit 20 proceeds to step S17, sets flag *1 (Pn←*1) for the collision prediction point Pn (S17), and proceeds to step S19.

[0079] On the other hand, if the collision avoidance control unit 20 determines by the AEB operation judgment unit 24 that there will be no collision between the oncoming vehicle V and the own vehicle M (step S16: NO), the collision avoidance control unit 20 proceeds to step S18, sets the flag *0 (Pn←*0) for the collision prediction point Pn (S18), and proceeds to step S19.

[0080] When the process proceeds to step S19, the collision avoidance control unit 20 determines whether or not there is an n+1 vehicle lane on the side of the host vehicle M from the n vehicle lane (S19). The collision avoidance control unit 20 detects, by the oncoming vehicle recognition unit 22, whether or not there is an n+1 vehicle lane on the side of the host vehicle M from the n vehicle lane, based on the surrounding environment information.

[0081] If the n+1-th vehicle lane is present (step S19: YES), the collision avoidance control unit 20 returns to step S11 and repeatedly executes the processes from step S11 onward for the n+1-th vehicle lane. That is, the collision avoidance control unit 20 repeatedly executes the AEB intervention determination process of FIG. 3 according to the number of vehicle lanes in the oncoming lane.

[0082] On the other hand, if there is no (n+1)th vehicle lane (step S19: NO), the collision avoidance control unit 20 ends the AEB intervention determination process, and proceeds to step 9 of the oncoming vehicle collision determination process shown in FIG.

[0083] In addition, the oncoming vehicle recognition unit 22 may first detect the oncoming vehicle V starting from the nth vehicle lane (n=max) closest to the host vehicle in the oncoming lane, and in this case, in step S19, it determines whether or not there is an n-1th vehicle lane further away from the host vehicle M than the nth vehicle lane.

[0084] When the process proceeds to step S9 of the oncoming vehicle collision determination process shown in Fig. 2, the collision avoidance control unit 20 performs AEB execution process (S9). This AEB execution process is a subroutine that the collision avoidance control unit 20 performs according to the routine of Fig. 4.

[0085] In the AEB execution process shown in Fig. 4, the collision avoidance control unit 20 determines whether or not the flag *1 (P1←*1) of the collision prediction point P1 of the first vehicle lane is set (S21). The collision avoidance control unit 20 determines whether or not the flag *1 (P1←*1) of the collision prediction point P1 of the first vehicle lane determined by the AEB operation determination unit 24 in step S17 in Fig. 3 is set.

[0086] Then, if the flag *1 (P1←*1) of the collision prediction point P1 in the first vehicle lane is set (step S21: YES), the collision avoidance control unit 20 proceeds to step S22.

[0087] On the other hand, if the flag *1 (P1←*1) of the collision prediction point P1 of the first vehicle lane is not set (step S21: NO), the collision avoidance control unit 20 proceeds to step S25. That is, if the flag *0 (P1←*0) of the collision prediction point P1 of the first vehicle lane is set, the collision avoidance control unit 20 proceeds to step S25.

[0088] When the process proceeds to step S22, the collision avoidance control unit 20 intervenes in warning / AEB control to stop the host vehicle M at a collision avoidance point Pa, which is a collision avoidance position. The collision avoidance point Pa is set, for example, as shown in Fig. 7, at a position on the host vehicle's predicted traveling path before the collision prediction point P1 in order to avoid the host vehicle M colliding with an oncoming motorcycle V1, which is an oncoming vehicle V. The collision avoidance point Pa is set to a front position of the host vehicle M on the host vehicle's predicted traveling path where the host vehicle M will not come into contact with or collide with the oncoming vehicle V.

[0089] When the process proceeds to step S23, the collision avoidance control unit 20 determines whether or not an oncoming vehicle V has been detected in the second vehicle lane (S23). The collision avoidance control unit 20 detects an oncoming vehicle V (here, an oncoming vehicle V2) in the second vehicle lane of the oncoming lane by the oncoming vehicle recognition unit 22 based on the surrounding environment information.

[0090] Then, if the oncoming vehicle recognition unit 22 detects an oncoming vehicle V in the second vehicle lane of the oncoming lane (step S23: YES), the collision avoidance control unit 20 proceeds to step S24. If the oncoming vehicle recognition unit 22 does not detect an oncoming vehicle V in the second vehicle lane of the oncoming lane (step S23: NO), the collision avoidance control unit 20 ends the AEB execution process or proceeds to the next step S.

[0091] In step S24, the collision avoidance control unit 20 determines whether or not the flag *1 (P2←*1) of the collision prediction point P2 of the second vehicle lane is set (S24). The collision avoidance control unit 20 determines whether or not the flag *1 (P2←*1) of the collision prediction point P2 of the second vehicle lane determined by the AEB operation determination unit 24 in step S17 of FIG. 3 is set.

[0092] Then, if the flag *1 (P2←*1) of the collision prediction point P2 of the second vehicle lane is set (step S24: YES), the collision avoidance control unit 20 proceeds to step S25. On the other hand, if the flag *1 (P2←*1) of the collision prediction point P2 of the second vehicle lane is not set (step S24: NO), the collision avoidance control unit 20 proceeds to step S26.

[0093] When proceeding to step S25, the collision avoidance control unit 20 changes to the intervention of warning·AEB control in which the host vehicle M stops at the collision avoidance point Pb which is the collision avoidance position. Note that, for example, as shown in FIG. 8, the collision avoidance control unit 20 sets the collision avoidance point Pb at a position in front of the collision prediction point P2 in the second vehicle passing zone on the predicted traveling path of the host vehicle, in order to avoid a collision between the host vehicle M and the oncoming vehicle V, here the oncoming vehicle V2, and then ends the AEB execution process or proceeds to the next step S. This collision avoidance point Pb is also the front position of the host vehicle M where it does not contact or collide with the oncoming vehicle V.

[0094] When proceeding to step S26, the collision avoidance control unit 20 changes to the intervention of warning·AEB control in which a predetermined host vehicle speed remains such that the host vehicle M does not stop at the collision avoidance point Pa which is the collision avoidance position (S26). Here, the collision avoidance control unit 20 decelerates to the collision avoidance point Pa where the host vehicle M avoids a collision with the oncoming vehicle V (oncoming motorcycle V1) traveling in the first vehicle passing zone, and executes AEB control with a brake assist amount such that a predetermined host vehicle speed remains without stopping.

[0095] That is, the host vehicle M increases the deceleration until the collision avoidance point Pa, and at the collision avoidance point Pa, the state is such that kinetic energy remains in the traveling direction. Therefore, it is easier for the host vehicle M to re-accelerate than when starting from a stop. Note that the predetermined host vehicle speed (Vm) at the collision avoidance point Pa is set in advance to be, for example, 0 km / h < Vm < 10 km / h, which is a vehicle speed at which the host vehicle M can stop immediately if it applies the brakes.

[0096] Next, the collision avoidance control unit 20 determines whether or not the oncoming vehicle V traveling in the first vehicle passing zone has passed the collision prediction point P1 (S27). The collision avoidance control unit 20 detects based on the surrounding environment information whether or not the oncoming vehicle V (here, the oncoming motorcycle V1) in the first vehicle passing zone of the oncoming lane has passed the collision prediction point P1.

[0097] Then, if the oncoming vehicle V (oncoming motorcycle V1) has passed the collision prediction point P1 (step S27: YES), the collision avoidance control unit 20 ends the AEB execution process or proceeds to the next step S.

[0098] At this time, as shown in FIG. 9, for example, the oncoming motorcycle V1 in the first vehicle lane has passed the predicted collision point P1, and the oncoming automobile V2 in the second vehicle lane has not yet reached the predicted collision point P2, so that the host vehicle M can accelerate again to turn right and pass through the intersection without colliding with the oncoming motorcycle V1 and the oncoming automobile V2.

[0099] On the other hand, if the oncoming vehicle V (oncoming motorcycle V1) has not passed the collision prediction point P1 due to deceleration or the like (step S27: NO), the collision avoidance control unit 20 proceeds to step S28.

[0100] When the process proceeds to step S28, the collision avoidance control unit 20 determines whether or not the host vehicle M has passed the collision prediction point P2 of the second vehicle lane (S28). The collision avoidance control unit 20 detects whether or not the host vehicle M has passed the collision prediction point P2 of the second vehicle lane based on the surrounding environment information.

[0101] If the host vehicle M has passed the collision prediction point P2 (step S28: YES), the collision avoidance control unit 20 proceeds to step S29. On the other hand, if the host vehicle M has not passed the collision prediction point P2 (step S28: NO), the collision avoidance control unit 20 proceeds to step S30.

[0102] When the process proceeds to step S29, the collision avoidance control unit 20 forcibly executes warning / AEB control to stop the host vehicle M before the predicted collision point P1 (S29), and ends the AEB execution process or proceeds to the next step S.

[0103] Here, the collision avoidance control unit 20 forcibly executes AEB control to stop the host vehicle M as close as possible to a predicted collision point P1 at which the host vehicle M will collide with an oncoming vehicle V (oncoming motorcycle V1) traveling in the first vehicle lane.

[0104] At this time, the host vehicle M will suddenly stop just before the collision prediction point P1, for example, as shown in Figure 10, to avoid a collision with an oncoming vehicle V, which is an oncoming motorcycle V1, traveling in the first vehicle lane, and to allow an oncoming automobile V2, which is an oncoming vehicle V, traveling in the second vehicle lane, to avoid a collision to the right side of the host vehicle M.

[0105] Furthermore, when the process proceeds to step S30, the collision avoidance control unit 20 forcibly executes warning / AEB control to stop the host vehicle M before the predicted collision point P2 (S30), and ends the AEB execution process or proceeds to the next step S.

[0106] Here, the collision avoidance control unit 20 forcibly executes AEB control to stop the host vehicle M as close as possible to a predicted collision point P2 at which the host vehicle M will collide with an oncoming vehicle V (oncoming vehicle V2) traveling in the second vehicle lane.

[0107] At this time, the host vehicle M will stop suddenly just before the collision prediction point P2, for example, as shown in Figure 11, to allow the oncoming vehicle V2, which is an oncoming vehicle V traveling in the second vehicle lane, to avoid a collision to the left side of the host vehicle M.

[0108] However, regardless of whether the host vehicle M stops before the predicted collision point P1 or P2, the judgment routine of step S24 determines that the host vehicle M is under conditions where it will not collide with the oncoming vehicle V2, which is an oncoming vehicle V traveling in the second vehicle lane, and therefore the driver of the oncoming vehicle V2 can slow down to avoid a collision with the host vehicle M.

[0109] In the above explanation, the collision avoidance control unit 20 has exemplified an oncoming lane as a two-lane road with up to the second lane, and in the case of an oncoming lane with a third lane or more, executes a setting that changes to intervention of warning / AEB control so that the host vehicle M stops at a collision avoidance point according to the number of lanes.

[0110] Furthermore, when the collision avoidance control unit 20 ends the AEB execution process in step 9 of the oncoming vehicle collision determination process shown in FIG. 2, the collision avoidance control unit 20 returns to step S1 and repeatedly executes the subsequent processes.

[0111] Incidentally, when the vehicle M is turning to cross the oncoming lane at an intersection (when turning right in the above description), if the collision avoidance control unit 20 sets an alarm / AEB control intervention, the cruise control unit 10 activates the alarm device 8 to notify the driver that there is a high possibility of a collision with the oncoming vehicle V.

[0112] Then, the cruise control unit 10 calculates the brake assist amount according to the positions of the collision avoidance points Pa, Pb with the oncoming vehicle V. If the cruise control unit 10 determines from this state that it is difficult to avoid the collision through the collision avoidance operation (mainly braking operation) by the driver, it forcibly operates the brake drive unit 7 to assist the collision avoidance operation by the driver.

[0113] In this way, the vehicle driving assistance device 1 of this embodiment detects an oncoming vehicle V in an oncoming lane having multiple vehicle lanes, and intervenes warning and AEB control for the oncoming vehicle V that is highly likely to collide with the host vehicle M.

[0114] For example, when a road has two oncoming lanes, if the vehicle driving assistance device 1 activates AEB control only for an oncoming motorcycle V1 traveling in the first vehicle lane, the host vehicle M will stop in the second vehicle lane at the collision avoidance point Pa.

[0115] At this time, the host vehicle M is in a situation where it blocks the path of the oncoming vehicle V2 traveling in the second vehicle lane. As a result, there is a risk that the oncoming vehicle V2 will collide with the side of the host vehicle M.

[0116] In addition, the vehicle driving assistance device 1 can also control the host vehicle M not to enter an intersection when activating AEB control for an oncoming vehicle V traveling in the oncoming lane, regardless of the vehicle lane.

[0117] However, with this type of control, the automatic emergency braking system (AEB) will be activated at a position contrary to the will of the driver who is trying to turn right at the intersection in accordance with the position of the oncoming vehicle V. As a result, if the automatic emergency braking system (AEB) is activated against the driver's will, the driver may become confused and make an error in driving operations, and there is a risk that the vehicle M will become stuck in the intersection.

[0118] In contrast, the vehicle driving assistance device 1 of this embodiment can perform rational automatic emergency braking (AEB) operation for each oncoming vehicle V traveling in a plurality of vehicle lanes in the oncoming lane.

[0119] Specifically, before the host vehicle M enters an intersection, the vehicle driving assistance device 1 determines the possibility of collision with an oncoming vehicle V (oncoming motorcycle V1) in the first vehicle lane of the oncoming lane.

[0120] Then, when the vehicle driving assistance device 1 determines that it is necessary to activate an automatic emergency braking system (AEB) for an oncoming vehicle V in the first vehicle lane, it sets a collision prediction point P1 where the predicted path of the vehicle M intersects with the path of the oncoming vehicle V in the first vehicle lane.

[0121] At this time, the vehicle driving support device 1 provisionally determines control to activate an automatic emergency brake (AEB) for the collision prediction point P1. The vehicle driving support device 1 also intervenes in warning and AEB control to stop the host vehicle M at a collision avoidance point Pa before the collision prediction point P1 to avoid a collision with an oncoming vehicle V in the first vehicle lane.

[0122] Furthermore, before the host vehicle M enters the intersection, the vehicle driving assistance device 1 determines the possibility of collision with an oncoming vehicle V (oncoming vehicle V2) in the second vehicle lane of the oncoming lane.

[0123] Then, when the vehicle's driving assistance device 1 determines that it is necessary to activate an automatic emergency braking system (AEB) for an oncoming vehicle V in the second vehicle lane, it sets a collision prediction point P2 where the predicted path of the vehicle M intersects with the path of the oncoming vehicle V in the second vehicle lane.

[0124] At this time, the vehicle driving support device 1 changes to a control for activating an automatic emergency brake (AEB) for the collision prediction point P2. The vehicle driving support device 1 also intervenes in warning and AEB control to stop the host vehicle M at a collision avoidance point Pb before the collision prediction point P2 for avoiding a collision with an oncoming vehicle V in the second vehicle lane.

[0125] In this way, the vehicle driving assistance device 1 causes the collision avoidance control unit 20 provided in the cruise control unit 10 to execute warning / AEB control via the AEB operation determination unit 24 at a collision avoidance point Pb on the vehicle's predicted path of travel that corresponds to the collision predicted point P2 in the second vehicle lane that is closest to the vehicle M, among the collision predicted points P1, P2.

[0126] Furthermore, when there is no possibility of collision with an oncoming vehicle V (oncoming automobile V2) in the second vehicle lane, the vehicle driving assistance device 1 intervenes in the AEB control so that a predetermined vehicle speed at which the host vehicle M does not stop is maintained at a collision avoidance point Pa before a collision prediction point P1 at which a collision with an oncoming vehicle V (oncoming motorcycle V1) in the first vehicle lane is avoided. This makes it easier for the host vehicle M to re-accelerate compared to starting from a stop, and makes it possible to avoid a side collision of the oncoming vehicle V (oncoming automobile V2) in the second vehicle lane with the host vehicle M.

[0127] That is, the host vehicle M has improved responsiveness in re-accelerating after the oncoming vehicle V in the first vehicle lane passes the collision prediction point P1 by retaining kinetic energy, so that the host vehicle M can pass the intersection more quickly and reduce the risk of collision with the oncoming vehicle V in the second vehicle lane.

[0128] That is, for example, when an oncoming vehicle V in the second vehicle lane approaches the host vehicle M while the host vehicle M is turning (turning right) at an intersection, the vehicle driving assistance device 1 activates an automatic emergency brake (AEB) to keep the host vehicle M at a speed that does not cause the host vehicle M to stop in the intersection. This shortens the time it takes for the host vehicle M to restart, and reduces the risk of an accident with the oncoming vehicle V in the second vehicle lane.

[0129] The intervention of warning and AEB control by the vehicle driving assistance device 1 described above has been exemplified as an example of a road with two oncoming lanes, but is not limited to this and can also be applied to intervention of warning and AEB control to stop the host vehicle M at a collision avoidance point depending on the number of oncoming lanes.

[0130] As described above, the vehicle driving assistance device 1 of this embodiment can perform rational automatic emergency braking (AEB) operation to avoid a collision between the vehicle M and oncoming vehicle V when turning and crossing the oncoming lane at an intersection (here, an example is given of an area where traffic keeps on the left, and turning right at an intersection), particularly in an oncoming lane with multiple lanes.

[0131] The cruise control unit (ECU) 10 and the collision avoidance control unit 20 each have a processor including a central processing unit (CPU), and storage devices such as a ROM and a RAM. All or part of the configuration of the multiple circuits of the processor may be implemented by software. For example, the CPU may read and execute various programs corresponding to the respective functions stored in the ROM.

[0132] Furthermore, all or part of the functions of the processor may be configured using logic circuits or analog circuits, and the processing of various programs may be realized by electronic circuits such as FPGAs.

[0133] The invention described in the above embodiments is not limited to those embodiments, and various modifications can be made in the implementation stage without departing from the gist of the invention. Furthermore, each of the above embodiments includes inventions at various stages, and various inventions can be extracted by appropriate combinations of the disclosed constituent elements.

[0134] For example, if some of the constituent elements shown in each form are deleted, and the stated problem can be solved and the stated effect can be obtained, the configuration from which these constituent elements are deleted can be extracted as an invention. [Explanation of symbols]

[0135] 1. Driving support device 2...Surrounding environment recognition unit 3...Ambient environment sensor 4. Surrounding environment recognition section 5…Road map database 6. Road map information 7…Brake drive section 8…Alarm device 9…Receiver 9…GNS receiver 10...ECU (Electric Control Unit) 10...Drive control unit 20...Collision avoidance control unit 21... Vehicle position estimation unit 22…Oncoming vehicle detection unit 23...Collision prediction calculation section 24...AEB operation determination section (collision avoidance operation determination section) M…Own vehicle P1, P2: collision prediction points Pa,Pb…Collision avoidance point Tmn,Tvn…Arrival time Tnth: Threshold V: Oncoming vehicle V1: Oncoming motorcycle V2, V3: Oncoming vehicles

Claims

1. a surrounding environment recognition unit that acquires surrounding environment information in front of the host vehicle; A travel control unit that operates the brake drive unit; A collision avoidance control unit provided in the driving control unit; having The collision avoidance control unit is a vehicle position estimating unit that estimates a position of the vehicle and generates a predicted travel path of the vehicle when the vehicle turns and crosses an oncoming lane at an intersection; an oncoming vehicle recognition unit that recognizes oncoming vehicles traveling in each vehicle lane of the oncoming lane based on the surrounding environment information; a collision prediction calculation unit that detects a collision prediction position where the predicted travel path of the host vehicle and the travel path of the oncoming vehicle intersect for each vehicle lane and predicts a collision between the host vehicle and the oncoming vehicle; a collision avoidance operation determination unit that determines whether or not the cruise control unit should execute collision avoidance control for operating the brake drive unit at the collision prediction position where a collision between the host vehicle and the oncoming vehicle is predicted by the collision prediction calculation unit; Equipped with a collision avoidance control unit that performs the collision avoidance control by executing the collision avoidance control operation on the vehicle's predicted path of travel at a collision avoidance position on the vehicle's predicted path of travel that corresponds to the predicted collision position, and that causes the vehicle to perform the collision avoidance control operation by the collision avoidance operation determination unit.

2. 2. The vehicle driving assistance device according to claim 1, wherein the collision avoidance control unit intervenes in the collision avoidance control so that the host vehicle maintains a predetermined host vehicle speed at the collision avoidance position such that the host vehicle does not stop.

3. 3. The vehicle driving assistance device of claim 1, wherein the collision avoidance control unit executes the collision avoidance control to forcibly stop the host vehicle just before the first predicted collision position when, based on the surrounding environment information, the host vehicle has not passed a first predicted collision position with a first oncoming vehicle traveling in a first vehicle lane in the oncoming lane that is farthest from the host vehicle, and has passed a second predicted collision position with a second oncoming vehicle traveling in a second vehicle lane in the oncoming lane that is closer to the host vehicle than the first vehicle lane.

4. 4. The vehicle driving assistance device according to claim 3, wherein the collision avoidance control unit executes the collision avoidance control to forcibly stop the host vehicle before the second predicted collision position when the host vehicle has not passed the second predicted collision position.

Images