Vehicle control device, vehicle control method, and computer program product

Abstract

A vehicle control device, vehicle control method, and computer program product execute collision avoidance control by controlling an actuator for collision avoidance control to avoid a collision when there is a high probability of the vehicle colliding with a vehicle in front. The method includes: acquiring a predetermined direction of movement of the vehicle in front; prohibiting the execution of the collision avoidance control if the predetermined direction of movement of the vehicle in front is the same as the predetermined avoidance direction of the vehicle based on the collision avoidance control; and setting a control start condition for initiating the collision avoidance control in a manner that is more timely than if the predetermined direction of movement of the vehicle in front is not acquired.

Description

[0001] This application is a divisional application of the following application:

[0002] Invention title: Collision avoidance auxiliary device.

[0003] Parent application number: 202210060740.9. Technical Field

[0004] The present invention relates to a vehicle control device, a vehicle control method, and a computer program product for performing control to avoid collisions between a vehicle (the vehicle itself) and other vehicles (vehicles ahead) located in front of the vehicle. Background Technology

[0005] One type of conventional collision avoidance assist device, when there is a possibility that the vehicle will collide with an obstacle in front of it, automatically steers the vehicle along the avoidance path that allows it to avoid a collision with the obstacle and avoid collisions with other objects (see Patent Document 1).

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2017-43262

[0009] Furthermore, sometimes the obstacle in front of the vehicle is another vehicle, and the direction indicator of that vehicle is flashing (indicating either left or right). In this case, the indicated direction may differ from the direction the vehicle intends to avoid the vehicle using steering avoidance control (either left or right, hereinafter referred to as the "predetermined avoidance direction"). In this situation, after the vehicle begins to travel along the avoidance path (i.e., after steering avoidance control begins), there is a high probability that the vehicle in front will move away from the vehicle. If steering avoidance control is initiated prematurely, and the vehicle in front subsequently moves in the indicated direction, the lateral movement of the vehicle based on that steering avoidance control may become excessive, or steering avoidance control may not have been necessary at all. As a result, there is a possibility that the driver may become bored with the steering avoidance control.

[0010] Conversely, if the direction indicated by the vehicle ahead is the same as the intended avoidance direction of this vehicle, there is a possibility that the vehicle ahead will gradually approach the avoidance path. In this case, the vehicle ahead may approach too closely as this vehicle attempts to avoid a collision using steering avoidance control, or the vehicle ahead may collide with this vehicle as it attempts to avoid a collision using steering avoidance control. Summary of the Invention

[0011] This disclosure is made to address the aforementioned problems. Specifically, one object of this disclosure is to provide a vehicle control device that, when performing collision avoidance control (steering avoidance control), prevents the vehicle from approaching the vehicle in front excessively, and reduces the likelihood of the driver becoming annoyed by the collision avoidance control. Hereinafter, the vehicle control device of this disclosure will sometimes be referred to as the "disclosure auxiliary device".

[0012] The auxiliary device (10) disclosed herein includes: a surrounding sensor (21), including a camera sensor (21b) that captures an area in front of the vehicle (SV) to acquire image data representing that area, and acquires information about a vehicle ahead (OV1) based at least on the image data, wherein the vehicle ahead (OV1) is another vehicle present in the area in front of the vehicle; a rudder angle actuator (52) configured to change the rudder angle of the vehicle; and a control unit (20) that, when a collision probability condition is determined to be met based on information from the surrounding sensor (steps 710, 715, 720), acquires a target track for avoiding a collision between the vehicle and the vehicle ahead by using calculations of the image data (step 815), and, when a predetermined steering avoidance control start condition is determined to be met (step 850), initiates steering avoidance control by controlling the rudder angle actuator to make the vehicle travel along the target track (step 855), wherein the collision probability condition is met when there is a possibility of a collision between the vehicle and the vehicle ahead.

[0013] Furthermore, the control unit is configured to: acquire avoidance predetermined direction information indicating which direction (left or right) the target track causes the vehicle to change course (step 830); determine, based on the image data, whether the state of the direction indicator of the vehicle ahead is a direction indication state indicating the predetermined direction of movement of the vehicle ahead (step 835); and if it is determined that the state of the direction indicator is the direction indication state, acquire, based on the image data, information indicating which direction (left or right) the predetermined direction of movement of the vehicle ahead indicated by the direction indicator is (step 860); and if it is determined that the state of the direction indicator is not the direction indication state, set the steering avoidance control start condition to a first start condition, which is the inter-vehicle distance between the vehicle ahead and the vehicle ahead. If the first distance condition is met (steps 840 and 845), and the direction indicator is determined to be in the direction indication state, the predetermined direction of movement of the vehicle ahead is determined to be the same as the predetermined direction of avoidance based on the information about the indicated direction and the predetermined direction of avoidance (step 865). If the predetermined direction of movement of the vehicle ahead is the same as the predetermined direction of avoidance, the execution of the steering avoidance control is prohibited (step 865: No, step 825). If the predetermined direction of movement of the vehicle ahead is different from the predetermined direction of avoidance, the steering avoidance control start condition is set to a second start condition. This second start condition is met at a time when the vehicle-to-vehicle distance is shorter than the first distance, which is the time when the first start condition is met (step 865: Yes, step 870, step 875).

[0014] According to the auxiliary device of this disclosure, it is determined whether the state of the direction indicator of the vehicle ahead is "a direction indication state indicating that the predetermined direction of movement of the vehicle ahead is either the left or the right direction". Furthermore, according to the auxiliary device of this disclosure, if it is determined that the state of the direction indicator of the vehicle ahead is a direction indication state and the predetermined direction of movement of the vehicle ahead is the same as the predetermined direction of avoidance, the execution of steering avoidance control is prohibited. Therefore, the auxiliary device of this disclosure can reduce the possibility of a collision between the vehicle and the vehicle ahead.

[0015] Furthermore, according to the auxiliary device of this disclosure, when it is determined that the direction indicator is not in a direction-indicating state, the steering avoidance control start condition is set to "a first start condition that can be established when the inter-vehicle distance between the vehicle and the vehicle in front is a first distance". Conversely, when it is determined that the direction indicator of the vehicle in front is in a direction-indicating state and the predetermined direction of movement of the vehicle in front is different from the predetermined direction of avoidance, the steering avoidance control start condition is set to a second start condition. This second start condition is a condition that can be established at a time when the inter-vehicle distance between the vehicle and the vehicle in front is a distance shorter than the inter-vehicle distance at the time when the first start condition is established. In other words, the second start condition is a condition that is established at a time later than the time when the first start condition is established. Therefore, the auxiliary device of this disclosure can reduce the possibility that the lateral movement of the vehicle based on steering avoidance control becomes excessive when the predetermined direction of movement of the vehicle in front is different from the predetermined direction of avoidance, and as a result, it can reduce the possibility that the driver will feel bored with steering avoidance control.

[0016] In one embodiment of the auxiliary device disclosed herein, the steering avoidance control initiation condition includes at least the condition that the collision index value (TTC), which indicates the probability of the vehicle colliding with the vehicle in front, has reached a collision probability threshold (TTCth), and the control unit sets the collision probability threshold (TTC2) used under the second initiation condition to a different value than the collision probability threshold (TTC1) used under the first initiation condition.

[0017] More specifically, the steering avoidance control start condition includes at least the condition that the predicted collision prediction time (TTC), which is the predicted value of the time until the vehicle collides with the vehicle in front, is shorter than a predetermined collision determination threshold time (TTCth). The control unit sets the collision determination threshold time (TTCth) used under the first start condition as a first time (TTC1), and the control unit sets the collision determination threshold time (TTCth) used under the second start condition as a second time (TTC2) that is shorter than the first time.

[0018] According to the above scheme, the collision determination threshold when the direction indicator of the vehicle ahead is in the direction-indicating state and the predetermined direction of movement of the vehicle ahead is different from the predetermined direction of avoidance is set to a value different from the collision determination threshold when the direction indicator of the vehicle ahead is not in the direction-indicating state. Therefore, the steering avoidance control start condition when the predetermined direction of movement of the vehicle ahead is determined to be different from the predetermined direction of avoidance can be set as a second start condition, which is achieved at a time when the inter-vehicle distance is a distance shorter than the inter-vehicle distance at the time when the first start condition can be achieved.

[0019] In the foregoing description, to aid in understanding the invention, the components of the invention corresponding to the embodiments described below are enclosed in parentheses with the names and / or reference numerals used in those embodiments. However, the constituent elements of the invention are not limited to the embodiments specified by the names and / or reference numerals. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the collision avoidance assist device according to an embodiment of the present disclosure.

[0021] Figure 2 This is a diagram used to illustrate an overview of steering avoidance control.

[0022] Figure 3 This is a diagram used to illustrate the first mapping diagram, Map1.

[0023] Figure 4 This diagram is used to illustrate the general working principle of the collision avoidance assist device.

[0024] Figure 5 This diagram is used to illustrate the general working principle of the collision avoidance assist device.

[0025] Figure 6 This is a diagram used to illustrate the second mapping diagram, Map2.

[0026] Figure 7 This is a flowchart showing the routines executed by the CPU of the driver assistance ECU.

[0027] Figure 8 This is a flowchart showing the routines executed by the CPU of the driver assistance ECU.

[0028] Figure 9 This is a flowchart showing the routines executed by the CPU of the driver assistance ECU.

[0029] Figure 10 This is a diagram used to illustrate the general operation of a modified example of a collision avoidance assist device.

[0030] Explanation of reference numerals in the attached figures

[0031] 10: Collision avoidance assist device; 20: Driver assistance ECU; 21: Surrounding sensors; 21a: Radar sensor; 21b: Camera sensor; 21c: Beacon recognition unit; 22: Vehicle speed sensor; 23: Yaw rate sensor; 24: Front and rear acceleration sensors; 25: Lateral acceleration sensor; 50: EPS ECU; 51: Motor driver; 52: Steering motor; SV: Vehicle. Detailed Implementation

[0032] <Composition>

[0033] like Figure 1 As shown, the collision avoidance assist device 10 of this invention is applied to a vehicle SV. To distinguish it from other vehicles, the vehicle SV is sometimes referred to as "this vehicle SV". The collision avoidance assist device 10 includes a driver assistance ECU 20, an engine ECU 30, a brake ECU 40, and an electric power steering ECU 50. It should be noted that, hereinafter, the driver assistance ECU 20 is referred to as "DS (Driving Support) ECU", and the electric power steering ECU 50 is referred to as "EPS (Electric Power Steering) ECU 50".

[0034] These ECUs are control units (electronic control units) with a microcomputer as their main component, also known as controllers. These ECUs are interconnected via CAN 70 (Controller Area Network) to exchange data (communication). The microcomputer includes a CPU, ROM, RAM, and interfaces (I / F). The CPU executes instructions (programs, routines) stored in ROM to perform various functions. Several or all of these ECUs can be integrated into a single ECU.

[0035] The DSECU is connected to ambient sensors 21, vehicle speed sensor 22, yaw rate sensor 23, front and rear acceleration sensors 24, and lateral acceleration sensor 25. The DSECU receives detection signals or output signals from these sensors. Some or all of these sensors can also be connected to an ECU other than the DSECU. In this case, the DSECU receives the detection signals or output signals from these sensors from other ECUs via CAN.

[0036] The ambient sensor 21 includes a radar sensor 21a, a camera sensor 21b, and a target recognition unit 21c. It should be noted that, from a functional point of view, the ambient sensor 21 constitutes an "obstacle recognition device." From a functional point of view, the camera sensor 21b constitutes a "direction acquisition device." It should be noted that the target recognition unit 21c includes an ECU, which includes a microcomputer.

[0037] The surrounding sensor 21 identifies three-dimensional objects existing in the "peripheral area of ​​the vehicle SV," which at least includes the "prescribed area in front of the vehicle SV (front area)," and acquires information related to the identified three-dimensional objects. The three-dimensional objects are moving objects (e.g., pedestrians and vehicles) or fixed objects (e.g., utility poles, trees, and guardrails). Hereinafter, three-dimensional objects are sometimes referred to as "objects."

[0038] The surrounding sensor 21 performs calculations to acquire information related to the identified object (hereinafter sometimes referred to as "object information") and sends it to the DSECU. The object information includes the following listed information.

[0039] • Longitudinal distance of the object Dfx: The longitudinal distance of the object Dfx is the marked distance between the front end of the vehicle SV and the object in the direction of the central axis (x-axis direction) extending in the longitudinal direction of the vehicle SV.

[0040] • Lateral position of the object Dfy: The lateral position of the object Dfy is the marked distance between the center position of the object and the central axis of the vehicle SV in the width direction, in a direction orthogonal to the central axis extending in the front-rear direction of the vehicle SV (y-axis direction).

[0041] • Relative velocity of the object Vfx: The relative velocity of the object Vfx is the difference between the velocity of the object in the x-axis direction Vb and the vehicle speed (velocity in the x-axis direction) Vs of the vehicle SV (=Vb-Vs).

[0042] • Information indicating the type of object (e.g., whether the object is a vehicle, a pedestrian, or a stationary object).

[0043] • The width of the object (the horizontal width of the object) W

[0044] • Length L of the object

[0045] It should be noted that the longitudinal distance Dfx and the lateral position Dfy are also referred to as the "detection position of the object".

[0046] The surrounding sensor 21 acquires target information based on predefined x-y coordinates. The x-axis extends along the longitudinal direction of the vehicle SV, passing through the center position of the front end of the vehicle SV in the width direction, and has the front as a positive value. The y-axis is orthogonal to the x-axis and has the left direction of the vehicle SV as a positive value. The origin of the x-axis and the origin of the y-axis are the predetermined positions of the vehicle SV (e.g., the center position of the front end of the vehicle SV in the width direction).

[0047] More specifically, radar sensor 21a includes a radar wave transceiver unit and a processing unit. The radar wave transceiver unit, for example, radiates millimeter-wave radio waves (hereinafter referred to as "millimeter waves") to a peripheral area of ​​the vehicle SV, which at least includes the area in front of the vehicle SV, and receives reflected waves generated by the radiated millimeter waves being reflected by portions of a three-dimensional object (i.e., reflection points). It should be noted that radar sensor 21a may also be a radar sensor using radio waves (radar waves) in frequency bands other than the millimeter-wave band.

[0048] The processing unit of radar sensor 21a determines the presence or absence of a target based on reflection point information, which includes the phase difference between the transmitted millimeter wave and the received reflected wave, the attenuation level of the reflected wave, and the time from the transmission of the millimeter wave to the reception of the reflected wave. The processing unit of radar sensor 21a groups "multiple reflection points" that are highly likely to detect a three-dimensional object, and identifies the group of reflection points as a target (for example, see Japanese Patent Application Publication Nos. 2019-003235, 2019-002691, and 2019-002690, etc.).

[0049] Furthermore, the processing unit of radar sensor 21a calculates the longitudinal distance Dfx of the object, the lateral position Dfy of the object, the azimuth θp of the object relative to the vehicle SV, and the relative speed Vfx between the vehicle SV and the object based on the reflection point information belonging to the reflection point of the identified object. Hereinafter, the information including these values ​​acquired by radar sensor 21a is sometimes referred to as "radar sensor detection information".

[0050] Camera sensor 21b includes a stereo camera and an image processing unit. The stereo camera captures the scenery of the "left and right areas" in front of the vehicle SV (i.e., the area in front of the vehicle SV) to acquire a pair of left and right images (i.e., image data representing the area in front). The image processing unit determines whether an object exists in the area in front of the vehicle SV based on this image data.

[0051] When the image processing unit determines that an object exists in the area in front of the vehicle SV, it calculates the object's orientation θp, longitudinal distance Dfx, and relative speed Vfx between the vehicle SV and the object based on image data. Furthermore, the image processing unit determines the type of the object through pattern matching based on the image data and obtains information indicating that object type. This information obtained by the image processing unit is sometimes referred to as "camera sensor detection information."

[0052] The object recognition unit 21c receives "radar sensor detection information" and "camera sensor detection information" from the processing unit of the radar sensor 21a and the image processing unit of the camera sensor 21b, respectively.

[0053] The object recognition unit 21c determines (acquires) the final object information of the aforementioned object based on "radar sensor detection information" and "camera sensor detection information". After a predetermined period of time, the object recognition unit 21c sends the determined final object information to the DSECU.

[0054] The image processing unit of camera sensor 21b identifies the left and right lane markings (hereinafter referred to as "white lines") of the road based on the acquired image data using well-known methods. For example, the image processing unit detects edge points where the brightness of the image changes abruptly, and extracts the outline of the white lines based on the detected edge points, thereby identifying the left and right white lines.

[0055] Then, every time a specified time has elapsed, the image processing unit calculates and obtains the position information of the left and right white lines of the lane (driving lane) in which the vehicle SV is traveling (the x-y coordinate position mentioned above) and sends it to the DSECU.

[0056] Furthermore, when the surrounding sensor 21 (image processing unit of camera sensor 21b) identifies an object located in front of the vehicle SV as a vehicle (hereinafter also referred to as "the vehicle in front"), it acquires the direction indicator information described below based on current and past image data, and sends the acquired direction indicator information to the DSECU. The direction indicator information includes the following information.

[0057] • Information about whether the direction indicator for the vehicle ahead is flashing (working).

[0058] • Information regarding whether only one of the left and right turn indicators of the vehicle ahead is flashing when the vehicle ahead's turn indicator is flashing.

[0059] • Indicates which of the left and right turn indicators is flashing when only one of the left and right turn indicators for the vehicle ahead is flashing (hereinafter, sometimes referred to as "information about the direction of travel" or "direction information").

[0060] Specifically, when only the left turn indicator (one of the left and right turn indicators) is flashing, the image processing unit acquires information indicating that the indicated direction is left as information about the direction of indication. When only the right turn indicator (one of the left and right turn indicators) is flashing, the image processing unit acquires information indicating that the indicated direction is right as information about the direction of indication. It should be noted that when both the left and right turn indicators are not flashing, or when both are flashing, the direction of indication is uncertain. Therefore, in these cases, the image processing unit sends information indicating that the state of the turn indicator does not represent a direction indication state (i.e., the meaning of the indicated direction cannot be determined) to the DSECU as information about the direction of indication.

[0061] The vehicle speed sensor 22 detects the vehicle speed (Vs) of the vehicle SV and outputs a signal indicating the detected vehicle speed Vs.

[0062] Yaw rate sensor 23 detects the yaw rate of the vehicle SV and outputs a signal representing the yaw rate Yr.

[0063] The front and rear acceleration sensors 24 detect the front and rear acceleration of the vehicle SV and output a signal representing the detected front and rear acceleration Gx. When the front and rear acceleration Gx is negative, the magnitude (absolute value) of the front and rear acceleration Gx represents the deceleration.

[0064] Lateral acceleration sensor 25 detects the lateral acceleration of the vehicle SV and outputs a signal representing the detected lateral acceleration Gy.

[0065] The engine ECU 30 is connected to the engine actuator 31. The engine actuator 31 includes a throttle actuator that changes the opening of the throttle valve of the engine 32. The engine ECU 30 can change the torque generated by the engine 32 by driving the engine actuator 31. The torque generated by the engine 32 is transmitted to the drive wheels via a transmission (not shown).

[0066] Therefore, the engine ECU 30 can control the driving force of the vehicle SV by controlling the engine actuator 31, thereby changing the acceleration state (rear acceleration Gx) of the vehicle SV. It should be noted that when the vehicle SV is a hybrid vehicle, the engine ECU 30 can control the driving force of the vehicle SV generated by either or both of the "engine and electric motor" that serve as the vehicle's drive source. Furthermore, when the vehicle SV is an electric vehicle, the engine ECU 30 can control the driving force of the vehicle SV generated by the electric motor that serves as the vehicle's drive source.

[0067] The brake ECU 40 is connected to the brake actuator 41. The brake actuator 41 is located in a hydraulic circuit between a master cylinder (not shown) that pressurizes the working fluid by the force applied by the brake pedal and friction brake mechanisms 42 located on the left and right front and rear wheels respectively. The friction brake mechanism 42 includes a brake disc 42a fixed to the wheel and a brake caliper 42b fixed to the vehicle body.

[0068] The brake actuator 41 adjusts the hydraulic pressure supplied to the wheel cylinders built into the brake caliper 42b according to instructions from the brake ECU 40, and uses this hydraulic pressure to operate the wheel cylinders. As a result, the brake actuator 41 presses the brake pads against the brake disc 42a to generate frictional braking force. Therefore, the brake ECU 40 can control the braking force of the vehicle SV by controlling the brake actuator 41, thereby changing the acceleration state (negative front-rear acceleration Gx) of the vehicle SV.

[0069] EPS·ECU 50 is a well-known control device for electric power steering systems. EPS·ECU 50 is connected to motor driver 51. Motor driver 51 is connected to steering motor 52. Steering motor 52 is embedded in a steering mechanism including a steering wheel SW, steering shaft SF, and a steering gear mechanism (not shown). Steering motor 52 is an electric motor that generates steering torque using electricity supplied from motor driver 51. Steering motor 52 uses this steering torque to turn the left and right steering wheels of the vehicle SV. In other words, steering motor 52 functions as a steering angle actuator that changes the steering angle (steering wheel angle) of the vehicle SV.

[0070] The EPS·ECU 50 is connected to the steering angle sensor 53 and the steering torque sensor 54. The steering angle sensor 53 detects the steering angle of the steering wheel SW of the vehicle SV and outputs a signal representing the steering angle θs. The steering torque sensor 54 detects the steering torque (hereinafter referred to as "drive torque TqDr") applied to the steering shaft SF of the vehicle SV by the operation of the steering wheel SW and outputs a signal representing the drive torque TqDr. The steering angle θs and drive torque TqDr are defined as being positive when the vehicle SV is turning left and negative when the vehicle SV is turning right.

[0071] The EPS·ECU50 drives the steering motor 52 based on the detected "drive torque TqDr, steering angle θs, and vehicle speed Vs". As a result, the EPS·ECU50 generates steering assist torque to assist the driver's steering operation.

[0072] In the execution of the steering avoidance control described later, when the EPS·ECU50 receives a steering command from the DSECU, it drives the steering motor 52 via the motor driver 51 based on the target steering angle (or target steering torque) determined by the steering command. Thus, the DSECU can automatically change the steering angle (steering wheel rotation) of the vehicle SV via the EPS·ECU50.

[0073]

[0074] like Figure 2 As shown, it is assumed that the following situation occurs: when vehicle SV is traveling in lane LA1, which is a straight road, there is a vehicle OV1 in front of vehicle SV as a three-dimensional object (landmark).

[0075] Each time a specified time has elapsed, the DSECU identifies the driving lane LA1, which is divided by the left white line WL and the right white line WR, based on the position information of the left white line WL and the right white line WR.

[0076] Furthermore, DSECU calculates the expected driving trajectory of the vehicle SV based on the steering angle θs, yaw rate Yr, and vehicle speed Vs, assuming that the vehicle SV will maintain its current driving state.

[0077] Assuming that the vehicle ahead (OV1) maintains its current driving state, the DSECU calculates the predicted trajectory of OV1 based on its landmark information. The predicted trajectory of OV1 is the path that OV1 is expected to take. More specifically, the DSECU calculates the predicted trajectory based on multiple detection positions of OV1 acquired at predetermined intervals in the past and the current detection position of OV1.

[0078] The DSECU determines whether the collision probability condition is met based on the predicted trajectory of the vehicle SV and the predicted trajectory of the vehicle OV1 ahead. The collision probability condition is met when, with both the vehicle OV1 maintaining its current movement and the vehicle SV maintaining its current driving state, there is a possibility of a collision between the vehicle SV and the vehicle OV1 (the two predicted trajectories intersect). If the DSECU determines that the collision probability condition is met, it determines that there is a possibility of a collision between the vehicle SV and the vehicle OV1 ahead (i.e., there is a vehicle OV1 ahead that has the potential to collide with the vehicle SV).

[0079] When the DSECU determines that there is a possibility of a collision between the vehicle SV and the vehicle ahead OV1, it calculates the collision prediction time TTC based on the longitudinal distance Dfx and relative speed Vfx of the vehicle ahead OV1. Specifically, the DSECU calculates the collision prediction time TTC by inverting the sign of the value obtained by dividing the longitudinal distance Dfx by the relative speed Vfx (i.e., TTC = -Dfx / Vfx). It should be noted that the DSECU can also calculate the collision prediction time TTC by dividing the distance between the location where the vehicle SV is expected to collide with the vehicle ahead OV1 (the intersection of the two predicted driving trajectories) and the vehicle SV by the vehicle SV's current speed Vs at the current time.

[0080] Furthermore, the DSECU calculates the possible trajectory to avoid a collision between the vehicle SV and the vehicle OV1 ahead using well-known methods. More specifically, the DSECU sets the trajectory through which the vehicle SV can avoid interference (collision) with the vehicle OV1 ahead as the avoidance target trajectory a1 (for example, regarding the determination of the avoidance target trajectory a1, see Japanese Patent Application Publication No. 2017-105383, Japanese Patent Application Publication No. 2017-43262, and Japanese Patent Application Publication No. 2018-106230, etc.).

[0081] In this example, the target trajectory a1 to be avoided is determined as follows: based on the object information about the vehicle OV1 ahead and the position information of the left and right white lines, at least all of the following conditions (conditions A1 to A3) are satisfied.

[0082] • Condition A1: There exists an avoidance space SP1 that the vehicle SV can pass through at either the left or right side of the vehicle OV1 at the location where a collision between the vehicle SV and the vehicle OV1 ahead is expected.

[0083] • Condition A2: When vehicle SV travels along the avoidance target track a1 from its current driving state, vehicle SV will not deviate from the driving lane LA1 defined by the left white line and the right white line.

[0084] • Condition A3: When the vehicle SV travels along the avoidance target trajectory a1 from its current driving state, it can maintain the magnitude of the lateral acceleration Gy and the magnitude of the yaw rate Yr below their respective thresholds, and pass through the avoidance space SP1.

[0085] Next, the DSECU determines whether the prescribed steering avoidance control initiation conditions are met. The steering avoidance control initiation conditions are conditions that are met if both the first condition and the second condition described below are met.

[0086] The first condition holds true when the collision prediction time TTC is shorter than the threshold time TTCth. It should be noted that, for convenience, the threshold time TTCth is also called the "collision determination threshold time." The collision prediction time TTC is a value where a smaller value indicates a higher probability of collision; it can also be called the collision index value. Therefore, it can be said that the first condition holds true when the probability of collision represented by the collision index value is above the collision probability threshold.

[0087] Second condition: The second condition is established when, assuming that the vehicle SV is traveling along the avoidance target track a1, there is no collision with the vehicle SV or the distance to the vehicle SV is less than the specified minimum distance from any other "object other than the preceding vehicle OV1".

[0088] When the steering avoidance control start condition is met, the DSECU calculates the target yaw rate to make the vehicle SV travel along the avoidance target trajectory a1.

[0089] The DSECU calculates the target yaw rate of the vehicle's SV steering wheels based on the calculated target yaw rate and the vehicle speed Vs of the vehicle's SV, and sends the steering command for collision avoidance, representing the target yaw rate, to the EPS·ECU50.

[0090] The EPS·ECU 50 calculates the target steering torque required to match the actual steering angle with the target steering angle. The EPS·ECU 50 drives the steering motor 52 to turn the steering wheels of the vehicle SV by outputting a steering torque corresponding to the calculated target steering torque. Based on this, the DSECU changes the steering angle of the vehicle SV via the EPS·ECU 50 to make the vehicle SV travel along the avoidance target trajectory a1. In this case, the vehicle SV will not deviate from the driving lane LA1, will not collide with other objects, and can avoid a collision with the vehicle in front OV1. The above is a basic overview of steering avoidance control.

[0091] <Summary of steering avoidance control corresponding to the state of the direction indicator>

[0092] If the DSECU determines that there is a possibility of a collision between the vehicle SV and the vehicle OV1 in front, it obtains the aforementioned "direction indicator information including direction information" from the surrounding sensors 21.

[0093] Furthermore, the DSECU obtains information about the predetermined avoidance direction of the vehicle SV based on the avoidance target track a1. For example, if the avoidance target track a1 curves to the right (i.e., if the avoidance target track a1 is a track that moves the position of the vehicle SV in the lane width direction to the right), the DSECU obtains information indicating that "the predetermined avoidance direction is to the right" as information about the predetermined avoidance direction. Similarly, if the avoidance target track a1 curves to the left (i.e., if the avoidance target track a1 is a track that moves the position of the vehicle SV in the lane width direction to the left), the DSECU obtains information indicating that "the predetermined avoidance direction is to the left" as information about the predetermined avoidance direction.

[0094] (The case where the direction indicator is not in the direction indicator state)

[0095] If the direction indicator is not in the aforementioned direction indicator state, the DSECU will set the threshold time TTCth used under the first condition of the steering avoidance control initiation condition to the first time TTC1. It should be noted that, for convenience, the steering avoidance control initiation condition in which the threshold time TTCth used under the first condition is set to the first time TTC1 is also referred to as the "first initiation condition." Setting the threshold time TTCth to the first time TTC1 can be considered synonymous with setting the collision probability threshold to the first probability threshold.

[0096] More specifically, the DSECU applies the absolute value (|Vfx|) of the relative speed Vfx of the vehicle ahead (OV1) to... Figure 3 The first mapping map Map1, shown as a lookup table, determines the first time TTC1. According to the first mapping map Map1, as shown by the dashed line Ln1, the first time TTC1 is set to be longer if the absolute value of the relative speed Vfx of the vehicle OV1 ahead is larger.

[0097] (When the direction indicated by the direction indicator of the vehicle ahead (OV1) is the same as the predetermined avoidance direction of this vehicle (SV))

[0098] exist Figure 4 In the example shown, the right-hand indicator of the vehicle ahead (OV1) is active (i.e., the direction indicated by the indicator is to the right), and the predetermined avoidance direction of this vehicle (SV) is to the right. Therefore, the direction indicated by the indicator is the same as the predetermined avoidance direction of this vehicle (SV).

[0099] When the direction indicated by the direction indicator of the vehicle ahead (OV1) is the same as the predetermined avoidance direction of the vehicle ahead (SV), there is a possibility that the vehicle ahead (OV1) will begin to move in the indicated direction after the steering avoidance control is initiated. If the vehicle ahead (OV1) begins to move in the indicated direction after the steering avoidance control is initiated, even if the vehicle ahead (SV) intends to avoid a collision with the vehicle ahead (OV1) through steering avoidance control, a collision between the two vehicles is likely. Therefore, in this situation, the DSECU prohibits the execution of steering avoidance control. Thus, although the DSECU executes steering avoidance control, it reduces the probability of a collision between the vehicle ahead (SV) and the vehicle ahead (OV1). It should be noted that the DSECU can also execute collision avoidance control implemented through the well-known automatic braking control. Therefore, in this situation, automatic braking control is used to avoid a collision between the vehicle ahead (SV) and the vehicle ahead (OV1).

[0100] (When the direction indicated by the vehicle ahead (OV1) differs from the predetermined avoidance direction of this vehicle (SV))

[0101] exist Figure 5In the example shown, the left-hand indicator of the vehicle ahead (OV1) is active (i.e., the indicator points to the left), and the intended avoidance direction of the vehicle SV is to the right. Therefore, the indicated direction of the indicator differs from the intended avoidance direction of the vehicle SV (they are opposite). When the indicated direction of the vehicle ahead (OV1) differs from the intended avoidance direction of the vehicle SV, there is a high probability that the vehicle ahead (OV1) will move away from the vehicle SV after the vehicle SV begins traveling along the avoidance path (i.e., after steering avoidance control begins). Therefore, if steering avoidance control is initiated prematurely, and the vehicle ahead (OV1) subsequently moves in the indicated direction, the lateral movement of the vehicle SV based on this steering avoidance control becomes excessive. As a result, there is a possibility that the driver may become bored with the steering avoidance control. In other words, there is a possibility that, even though the vehicle ahead (OV1) is expected to move away from the vehicle SV, and the driver has determined that avoidance through steering or a slight steering maneuver is sufficient, steering avoidance control will still be performed without considering such movement of the vehicle ahead (OV1). As a result, there is a possibility that some drivers will become bored with the steering avoidance control.

[0102] Therefore, in this case, the DSECU sets the first condition as follows: the distance between the vehicle SV and the preceding vehicle OV1 at the time when the first condition (TTC < TTCth) is met is shorter than the distance at the time when the first condition is met if the direction indicator is not in the direction indicator state. Specifically, in this case, the DSECU sets the threshold time TTCth of the first condition to a second time TTC2, which is shorter than the first time TTC1. It should be noted that, for convenience, the steering avoidance control start condition in which the threshold time TTCth used in the first condition is set to the second time TTC2 is also referred to as the "second start condition". It can be said that setting the threshold time TTCth to the second time TTC2 is synonymous with setting the collision probability threshold to a "second probability threshold greater than the first probability threshold".

[0103] More specifically, the DSECU applies the absolute value (|Vfx|) of the relative speed Vfx of the vehicle ahead (OV1) to... Figure 6 The second mapping map Map2, shown as a lookup table, determines the second time TTC2. According to Map2, as indicated by the solid line Ln2, the second time TTC2 is set to be longer if the absolute value of the relative speed Vfx of the preceding vehicle OV1 is larger. Moreover, according to Map2, the second time TTC2 is set to be shorter than the first time TTC1, indicated by the dashed line Ln1, for any absolute value (|Vfx|) of the relative speed Vfx of the preceding vehicle OV1.

[0104] Therefore, when the relative speed Vfx of the vehicle ahead OV1 is any value, the timing at which the steering avoidance control initiation condition is met when the threshold time TTCth is set to the second time TTC2 is later than the timing at which the steering avoidance control initiation condition is met when the threshold time TTCth is set to the first time TTC1. In other words, the second initiation condition is met when the distance between the current vehicle SV and the vehicle ahead OV1 is shorter than the distance between the current vehicle SV and the vehicle ahead OV1 at the time when the first initiation condition is met. Thus, the DSECU can reduce the likelihood of the driver becoming bored with the steering avoidance control.

[0105] <Specific tasks>

[0106] Every time a predetermined time elapses, the DSECU's CPU (hereinafter referred to as "CPU") executes... Figures 7 to 9 Each of the routines shown in the flowchart.

[0107] Therefore, when the specified timing is reached, the CPU starts from... Figure 7 Step 700 begins processing and proceeds to step 705, where the value of the collision probability indicator (Xf) is determined to be "0". If Xf is "0", it indicates that there is no vehicle OV1 ahead that could potentially collide with this vehicle SV. If Xf is "1", it indicates that there is a vehicle OV1 ahead that could potentially collide with this vehicle SV. The value of Xf is set to "0" in the initialization routine executed by the CPU when the ignition key switch (not shown) of this vehicle SV changes from the off position to the on position.

[0108] If the value of flag Xf is "0", the CPU determines "yes" in step 705 and proceeds to step 710, which determines whether there is a vehicle OV1 in front of the vehicle SV in a predetermined area based on the landmark information obtained from the surrounding sensor 21. For example, the area in front is a range within a predetermined distance from the vehicle SV in the direction of travel of the vehicle SV, and is a range with a width in the width direction of the vehicle SV that is a predetermined distance wider than the width of the vehicle SV.

[0109] If there is no vehicle OV1 in front of this vehicle SV, the CPU determines "no" in step 710 and proceeds to step 795, temporarily ending this routine.

[0110] If a vehicle OV1 is present in the area in front of the vehicle SV, the CPU determines "yes" in step 710 and proceeds to step 715, using the method described above to determine whether there is a possibility of a collision between the vehicle SV and the vehicle OV1. That is, the CPU determines whether the above-mentioned collision possibility conditions have been met.

[0111] If there is no possibility of a collision between the vehicle SV and the vehicle OV1 in front, the CPU determines "no" in step 715 and proceeds to step 795, temporarily ending this routine.

[0112] Conversely, if there is a possibility of a collision between the vehicle SV and the vehicle OV1 ahead, the CPU determines "yes" in step 715 and proceeds to step 720, setting the value of the flag Xf to "1". Afterwards, the CPU proceeds to step 795 and temporarily terminates the current routine.

[0113] It should be noted that if the value of the time point flag Xf when the CPU executes step 705 is "1", the CPU will determine "no" in step 705 and proceed to step 795, temporarily ending this routine.

[0114] When the specified timing is reached, the CPU... Figure 8 Step 800 begins processing and proceeds to step 805, determining whether the steering avoidance control is not in execution (whether the steering avoidance control is not in execution). More specifically, at the current point in time, during the control execution period from the start of steering avoidance control to the end of steering avoidance control (or until steering avoidance control stops), the CPU determines that steering avoidance control is in execution (see below). Figure 9 Step 910. If the current time point is outside the control execution period, the CPU determines that the steering avoidance control is not being executed. If the current time point is within the control execution period, i.e., if the steering avoidance control is being executed, the CPU determines "No" in step 805 and proceeds to step 895, temporarily ending this routine.

[0115] In contrast, when steering avoidance control is not being executed, the CPU determines "yes" in step 805 and proceeds to step 810 to determine whether the value of the flag Xf is "1".

[0116] If the value of the flag Xf is "0", the CPU determines "no" in step 810 and proceeds to step 895, temporarily ending this routine.

[0117] Conversely, if the value of flag Xf is "1", the CPU determines "yes" in step 810 and proceeds to step 815 to calculate the avoidance target track a1 for the vehicle ahead OV1, which was determined in step 715 to have a possibility of colliding with the current vehicle SV. Then, the CPU proceeds to step 820 to determine whether there is an avoidance target track a1 (i.e., whether there is a track that satisfies all the conditions A1 to A3 mentioned above).

[0118] If there is no target trajectory a1 to avoid, the CPU determines "No" in step 820 and proceeds to step 825. After setting the value of flag Xf to "0", it proceeds to step 895 and temporarily terminates the current routine. Therefore, in this case, steering avoidance control for the vehicle OV1 ahead is not performed (steering avoidance control is prohibited). However, in this case, automatic braking control is generally performed.

[0119] In contrast, if there is a target trajectory a1 to avoid, the CPU determines "yes" in step 820 and proceeds to step 830, whereby it obtains the predetermined avoidance direction of the vehicle SV based on information about the predetermined avoidance direction. Then, the CPU proceeds to step 835, where it determines whether the state of the direction indicator is the aforementioned direction indication state (whether the direction indicated by the direction indicator of the preceding vehicle OV1 has been obtained) based on information about the indicated direction.

[0120] If the direction indicator is not in the aforementioned direction indicator state, the CPU determines "no" in step 835, and after sequentially executing the processes described below in steps 840 and 845, proceeds to step 850.

[0121] Step 840: The CPU obtains the first time TTC1 by applying the absolute value (|Vfx|) of the relative speed Vfx of the vehicle OV1 ahead to the first mapping map Map1.

[0122] Step 845: The CPU sets the threshold time TTCth to the first time TTC1.

[0123] Subsequently, regarding the CPU, upon entering step 850, it determines whether the aforementioned steering avoidance control start condition (i.e., both the first and second conditions) is met. It should be noted that in this case, the first time TTC1 is set to the threshold time TTCth of the first condition.

[0124] If the steering avoidance control start condition is not met, the CPU determines "no" in step 850 and proceeds to step 895, temporarily ending this routine.

[0125] If the steering avoidance control initiation condition is met, the CPU determines "yes" in step 850 and proceeds to step 855 to begin executing the steering avoidance control. That is, the CPU begins to steer the vehicle SV along the avoidance target trajectory a1. Afterward, the CPU proceeds to step 895 and temporarily terminates the current routine.

[0126] At the point in time when the CPU executes step 835, if the direction indicator is in the aforementioned direction indication state, the CPU determines "yes" in step 835 and proceeds to step 860. In step 860, the CPU obtains the indication direction based on information about the indication direction. Next, the CPU proceeds to step 865 to determine whether the direction indicated by the direction indicator is different from the predetermined avoidance direction.

[0127] If the direction indicated by the direction indicator is the same as the predetermined avoidance direction, the CPU determines "No" in step 865 and proceeds to step 825. After setting the value of flag Xf to "0", it proceeds to step 895 and temporarily terminates the current routine. Therefore, in this case, steering avoidance control for the vehicle OV1 in front is not performed (steering avoidance control is prohibited).

[0128] If the direction indicated by the direction indicator is different from the predetermined avoidance direction, the CPU determines "yes" in step 865, and after executing the processes described below in "steps 870 and 875", proceeds to step 850.

[0129] Step 870: The CPU obtains the second time TTC2 by applying the absolute value (|Vfx|) of the relative speed Vfx of the vehicle OV1 ahead to the second map Map2.

[0130] Step 875: The CPU sets the threshold time TTCth to the second time TTC2. As mentioned above, the second time TTC2 for any absolute value (|Vfx|) is shorter than the first time TTC1 for that arbitrary absolute value (|Vfx|).

[0131] As far as the CPU is concerned, when entering step 850, it determines whether the aforementioned steering avoidance control start condition (i.e., both the first condition and the second condition) is met. It should be noted that in this case, the second time TTC2 is set to the threshold time TTCth of the first condition.

[0132] If the steering avoidance control start condition is not met, the CPU determines "no" in step 850 and proceeds to step 895, temporarily ending this routine.

[0133] Conversely, if the steering avoidance control start condition is met, the CPU determines "yes" in step 850 and proceeds to step 855 to begin executing the steering avoidance control. In this case, the steering avoidance control starts at a later timing compared to the case where the threshold time TTCth for the steering avoidance control start condition is set to the first time TTC1. In other words, since the threshold time TTCth for the steering avoidance control start condition is set to the second time TTC2, the steering avoidance control starts at the point when the distance between the current vehicle SV and the preceding vehicle OV1 becomes smaller compared to the case where the threshold time TTCth for the steering avoidance control start condition is set to the first time TTC1. Afterward, the CPU proceeds to step 895 and temporarily terminates the current routine.

[0134] When the specified timing is reached, the CPU... Figure 9 Step 900 begins processing and proceeds to step 905, where it is determined whether steering avoidance control is being executed.

[0135] If steering avoidance control is not being executed, the CPU determines "no" in step 905 and proceeds to step 995, temporarily ending this routine.

[0136] If steering avoidance control is in progress, the CPU determines "yes" in step 905 and proceeds to step 910 to determine whether the prescribed termination condition for steering avoidance control has been met. For example, the termination condition for steering avoidance control is met when the vehicle SV is traveling along the avoidance target track a1 and is parallel to the vehicle OV1 in the lane width direction.

[0137] If the termination condition for steering avoidance control is not met, the CPU determines "no" in step 910 and proceeds to step 995, temporarily ending this routine.

[0138] If the termination condition for steering avoidance control has been met, the CPU determines "yes" in step 910. After executing the processes described below in "steps 915 and 920", it proceeds to step 995 and temporarily terminates the routine.

[0139] Step 915: The CPU terminates steering avoidance control.

[0140] Step 920: The CPU sets the value of flag Xf to "0".

[0141] This disclosure is not limited to the above-described embodiments. Within the scope of this disclosure, various modifications based on the technical concept of this disclosure can be adopted.

[0142] For example, in the above embodiment, each of the first time TTC1 and the second time TTC2 can also be changed according to the overlap ratio LR. In this case, the overlap ratio LR is an indicator representing the degree of overlap between the vehicle SV and the preceding vehicle OV1 in the vehicle width direction at the point when a collision is expected. The overlap ratio LR is calculated by dividing the length of overlap between the vehicle SV and the preceding vehicle OV1 in the vehicle width direction by the width of the vehicle SV. In this case, the first time TTC1 is set such that the larger the overlap ratio LR, the longer the first time TTC1. The second time TTC2 is set such that the larger the overlap ratio LR, the longer the second time TTC2, and it is shorter than the first time TTC1 corresponding to the same absolute value (|Vfx|) and the same overlap ratio LR.

[0143] In the above embodiments, at least a portion of the processing performed by the object recognition unit 21c and / or the surrounding sensors 21 may also be performed by the DSECU. Moreover, the collision index value is not limited to the collision prediction time TTC, and may be obtained by applying the relative positions of the vehicle SV and the preceding vehicle OV1, the motion state of the vehicle SV, and the motion state of the preceding vehicle OV1 to a predetermined lookup table.

[0144] <Variation Example>

[0145] Furthermore, as another variation of this disclosure, the following variation can also be adopted. This variation calculates the target trajectory and the limit index value (turning avoidance limit index value) TTS as described later, and initiates turning avoidance control when the limit index value TTS becomes "0". That is, the limit index value TTS is the time from the current time point to the time point when turning avoidance control needs to be initiated. It can be said that the condition of the limit index value TTS being "0" is the first condition (i.e., TTC < TTCth) that replaces the aforementioned turning avoidance control initiation condition.

[0146] The following is for reference Figure 10 The workings of the modified examples will be explained in detail. Figure 10 The vertical axis of the coordinate system represents the lateral (width direction) position of the vehicle SV (hereinafter referred to as "lateral position"). The origin of this vertical axis is the center position of the front end of the vehicle SV in the width direction. The left direction of the vehicle SV is defined as the positive direction of the vertical axis. Figure 10 The horizontal axis of the coordinate system represents the elapsed time since the current point in time.

[0147] First, the DSECU uses the object information of the vehicle ahead (OV1) to calculate the collision prediction time (TTC) as described above.

[0148] Next, the DSECU uses the target information of the preceding vehicle OV1 to determine the first position P1a of time point tc1, which is the time point elapsed since the current time point after the collision prediction time TTC. The first position P1a is calculated by moving the lateral position P1 of the left rear end of the preceding vehicle OV1 at time point tc1 along... Figure 10 The vertical axis has been moved in the positive direction by a specified first distance d1 (margin) to its current position.

[0149] Similarly, DSECU calculates the second position P2a at time point tc1. The second position P2a is the lateral position P2 of the right rear end of the vehicle OV1 ahead of time point tc1 along... Figure 10 The vertical axis has been moved in the negative direction by a specified second distance d2 (margin) to its current position.

[0150] The DSECU calculates the target trajectory of the left front end LFr of the vehicle SV based on the lateral acceleration curve of the vehicle SV stored in ROM (the relationship between the elapsed time from the start of steering avoidance control and the lateral acceleration). This lateral acceleration curve is, for example, the following curve: from the start of steering avoidance control, the lateral acceleration increases proportionally to time from "0" to "lateral acceleration of magnitude A", and then is maintained at "lateral acceleration of magnitude A". It should be noted that when calculating the target trajectory of the left front end LFr, the DSECU uses the value obtained by adding a negative sign to the "magnitude of lateral acceleration specified by the lateral acceleration curve" as the lateral acceleration. For the DSECU, the starting point (initial point) of the target trajectory is located on the path LLFr that the left front end LFr of the vehicle SV will traverse, and the target trajectory is moved from the second position P2a, thereby calculating the collision avoidance prediction trajectory LO1 of the left front end LFr of the vehicle SV.

[0151] Next, the DSECU determines the "time point at which steering should begin (steering start time point) TS1" required for the left front end LFr of the vehicle SV to move on the collision avoidance prediction trajectory LO1. Furthermore, the DSECU calculates the time from the current time point to the steering start time point TS1 as the first steering start margin time T1. It should be noted that the DSECU can also calculate the first steering start margin time T1 by dividing the distance from the current position of the vehicle SV to the starting point PSL of the collision avoidance prediction trajectory LO1 by the vehicle speed Vs of the vehicle SV at the current time point.

[0152] Similarly, the DSECU calculates the target trajectory of the right front end RFr of the vehicle SV based on the aforementioned lateral acceleration curve. When calculating the target trajectory of the right front end RFr, the DSECU uses the value obtained by adding a positive sign to the "magnitude of the lateral acceleration as defined by the lateral acceleration curve" as the lateral acceleration. For the DSECU, the target trajectory is moved such that its starting point (initial point) is located on the path LRFr that the right front end RFr of the vehicle SV will traverse, and the target trajectory passes through the first position P1a, thereby calculating the collision avoidance prediction trajectory RO1 for the right front end RFr of the vehicle SV.

[0153] Next, the DSECU determines the "time point at which steering should begin (steering start time point) TS2" required for the right front end RFr of the vehicle SV to move on the collision avoidance prediction trajectory RO1. Furthermore, the DSECU calculates the time from the current time point to the steering start time point TS2 as the second steering start margin time T2. It should be noted that the DSECU can also calculate the second steering start margin time T2 by dividing the distance from the current position of the vehicle SV to the starting point PSR of the collision avoidance prediction trajectory RO1 by the vehicle speed Vs of the vehicle SV at the current time point.

[0154] Next, a summary of the steering avoidance control performed in this variant will be given.

[0155] In the modified example, the DSECU determines whether the above-mentioned collision possibility condition is met. If the collision possibility condition is met (that is, if it is determined that there is a possibility of collision with the vehicle SV by a vehicle OV1 in front), the following processing is performed.

[0156] (1) DSECU uses the above method to calculate the collision avoidance prediction trajectory LO1, the first steering start margin time T1, the collision avoidance prediction trajectory RO1, and the second steering start margin time T2.

[0157] (2) The DSECU determines whether the right-hand steering avoidance condition is met. The right-hand steering avoidance condition is met when the following two conditions are met.

[0158] • At the point when it is predicted that this vehicle SV will collide with the vehicle ahead OV1 (time point tc1 after the collision prediction time TTC has passed from the current time), there is an avoidance space to the right of the vehicle ahead OV1 that this vehicle SV will not deviate from its driving lane and that this vehicle SV can pass through.

[0159] • When the vehicle SV is traveling in a manner where the left front end LFr of the vehicle SV is moving on the collision avoidance prediction trajectory LO1, there are no other objects other than the vehicle ahead OV1 that will collide with the vehicle SV or whose distance from the vehicle SV is less than the specified minimum distance.

[0160] (3) The DSECU determines whether the left-hand steering avoidance condition is met. The left-hand steering avoidance condition is met when the following two conditions are met.

[0161] • At the point tc1 when it is expected that this vehicle SV will collide with the vehicle ahead OV1, there is a space to the left of the vehicle ahead OV1 that allows this vehicle SV to avoid deviating from its lane and pass through.

[0162] • When the vehicle SV is traveling in a manner where the right front end RFr of the vehicle SV is moving on the collision avoidance prediction trajectory RO1, there are no other objects other than the preceding vehicle OV1 that will collide with the vehicle SV or whose distance from the vehicle SV is less than the specified minimum distance.

[0163] (4) If neither the right-hand steering avoidance condition nor the left-hand steering avoidance condition is met, the DSECU disables steering avoidance control. At this time, the DSECU sets the limit index value TTS to an essentially infinite time.

[0164] (5) When the right-direction steering avoidance condition has been met, but the left-direction steering avoidance condition has not been met, the DSECU uses the collision avoidance prediction trajectory LO1 as the avoidance target trajectory of the left front end LFr of the vehicle SV, and uses the first steering start margin time T1 as the limit index value TTS.

[0165] (6) When the left-direction steering avoidance condition has been met, but the right-direction steering avoidance condition has not been met, the DSECU uses the collision avoidance prediction trajectory RO1 as the avoidance target trajectory of the right front end RFr of the vehicle SV, and uses the second steering start margin time T2 as the limit index value TTS.

[0166] (7) When both the right-hand steering avoidance condition and the left-hand steering avoidance condition are met, the DSECU uses the longer of the first steering start margin time T1 and the second steering start margin time T2 as the limit index value TTS. Moreover, the DSECU uses the collision avoidance prediction trajectory corresponding to the longer of the first steering start margin time T1 and the second steering start margin time T2 as the avoidance target trajectory for the front end (left front end LFr or right front end RFr) of the corresponding vehicle SV.

[0167] (8) Each time a specified time has elapsed, the DSECU repeatedly executes the above processes (1) to (7) to determine whether the limit index value TTS has become 0. If the limit index value TTS becomes 0, the DSECU further performs the following processes.

[0168] (9) The DSECU determines whether the direction indicator is in a direction-indicating state based on the direction indicator information. If the DSECU determines that the direction indicator is not in a direction-indicating state, it changes the steering angle of the vehicle SV so that "one of the right front end RFr and left front end LFr of the vehicle SV" that is suitable for the collision avoidance prediction trajectory set as the avoidance target trajectory moves on the avoidance target trajectory. That is, steering avoidance control begins. It should be noted that, for convenience, the start time of this steering avoidance control when the collision avoidance prediction trajectory LO1 is adopted as the avoidance target trajectory is called the "right-direction normal time point". For convenience, the start time of this steering avoidance control when the collision avoidance prediction trajectory RO1 is adopted as the avoidance target trajectory is called the "left-direction normal time point".

[0169] (10) If the DSECU determines, based on the direction indicator information and the target trajectory to be avoided, that the direction indicator of the preceding vehicle OV1 is in the direction indication state, it determines whether the indicated direction of the direction indicator of the preceding vehicle OV1 is different from the predetermined avoidance direction of the current vehicle SV. If the DSECU determines that the indicated direction of the direction indicator is the same as the predetermined avoidance direction of the current vehicle SV, it prohibits (does not start) steering avoidance control.

[0170] (11) In contrast, when the DSECU determines that the direction indicator of the vehicle ahead OV1 is in the direction indication state based on the direction indicator information and the target trajectory to be avoided, it does not immediately start steering avoidance control when it determines that the direction indicated by the direction indicator of the vehicle ahead OV1 is different from the predetermined avoidance direction of the vehicle SV, but performs the following further processing.

[0171] (11-1) Avoiding the case where the predetermined direction is to the right (i.e., the right-direction turning avoidance condition has been met, but the left-direction turning avoidance condition has not been met, and the collision avoidance prediction trajectory LO1 is adopted as the avoidance target trajectory).

[0172] In this case, DSECU calculates the lateral position P2 of the right rear end of the vehicle OV1 ahead of time point tc1 along... Figure 10 The coordinate axis is shifted in the negative direction by a position "less than the specified corrected second distance d2" to serve as the second position P2a.

[0173] Then, each time a predetermined time has elapsed, the DSECU repeatedly performs the following process: using the second position P2a, it recalculates the collision avoidance prediction trajectory LO1 of the left front end LFr as the avoidance target trajectory, and recalculates the first steering start margin time T1 (the time until the steering start time point TS1) as the limit index value TTS. From the point when the first steering start margin time T1 obtained in this way becomes "0" (hereinafter, for convenience, referred to as the "right direction delay time point"), the DSECU changes the steering angle of the vehicle SV, causing the left front end LFr to move on the avoidance target trajectory (collision avoidance prediction trajectory LO1). That is, steering avoidance control begins. This right direction delay time point is later in time than the aforementioned right direction normal time point. In other words, the vehicle SV at the right direction delay time point is shorter than the vehicle SV at the right direction normal time point. Thus, similar to the embodiment, this variation can reduce the possibility of the driver becoming bored with steering avoidance control.

[0174] (11-2) Avoiding the case where the predetermined direction is to the left (i.e., the left-direction turning avoidance condition has been met, but the right-direction turning avoidance condition has not been met, and the collision avoidance prediction trajectory RO1 is adopted as the avoidance target trajectory).

[0175] In this case, DSECU calculates the lateral position P1 of the left rear end of the vehicle OV1 ahead of time point tc1 along... Figure 10 The coordinate axis is moved in the positive direction by a position "less than the specified first correction distance of the first distance d1" to serve as the first position P1a.

[0176] Then, each time a predetermined time has elapsed, the DSECU repeatedly performs the following process: using the first position P1a, it recalculates the collision avoidance prediction trajectory RO1 of the right front end RFr as the avoidance target trajectory, and recalculates the second steering start margin time T2 (the time until the steering start time point TS2) as the limit index value TTS. From the point when the second steering start margin time T2 obtained in this way becomes "0" (hereinafter, for convenience, referred to as the "left direction delay time point"), the DSECU changes the steering angle of the vehicle SV, causing the right front end RFr to move on the avoidance target trajectory (collision avoidance prediction trajectory RO1). That is, steering avoidance control begins. This left direction delay time point is later in time than the aforementioned left direction normal time point. In other words, the vehicle SV at the left direction delay time point is shorter than the vehicle SV at the left direction normal time point. Thus, similar to the embodiment, this variation can reduce the possibility of the driver becoming bored with steering avoidance control.

Claims

1. A vehicle control device, comprising: The controller performs collision avoidance control by controlling the actuators used for collision avoidance control, which avoids a collision when there is a high probability of the vehicle colliding with the vehicle in front. The controller is configured to: Obtain the predetermined direction of movement of the vehicle ahead. If the predetermined direction of movement of the vehicle ahead is the same as the predetermined direction of avoidance of the vehicle based on the collision avoidance control, the execution of the collision avoidance control is prohibited. When the predetermined direction of movement of the vehicle ahead is different from the predetermined direction of avoidance of the vehicle based on the collision avoidance control, the control start condition for initiating the collision avoidance control is set in such a way that the control start condition is established at a later timing compared to the case where the predetermined direction of movement of the vehicle ahead is not acquired.

2. The vehicle control device according to claim 1, wherein, The controller is configured to: The predetermined direction of movement of the vehicle ahead is obtained based on the direction that the direction indicator is pointing when the direction indicator of the vehicle ahead is flashing.

3. The vehicle control device according to claim 2, wherein, In either the case where the left and right direction indicators of the vehicle ahead are both not flashing, or in the case where both the left and right direction indicators are flashing, the predetermined direction of movement of the vehicle ahead is not acquired.

4. A vehicle control method that executes collision avoidance control by controlling an actuator for collision avoidance control to avoid a collision when there is a high probability of the vehicle colliding with a vehicle in front. The vehicle control method includes: The step of obtaining the predetermined direction of movement of the vehicle ahead; The step of prohibiting the execution of the collision avoidance control when the predetermined direction of movement of the vehicle in front is the same as the predetermined direction of avoidance of the vehicle based on the collision avoidance control. as well as When the predetermined direction of movement of the vehicle ahead is different from the predetermined direction of avoidance of the vehicle based on the collision avoidance control, the step of setting the control start condition for starting the collision avoidance control is as follows: the control start condition is set at a later timing compared to the case where the predetermined direction of movement of the vehicle ahead is not acquired.

5. A computer program product comprising a computer program executed by a computer mounted in the vehicle to perform collision avoidance control by controlling an actuator for collision avoidance control to avoid a collision when the probability of a collision between the vehicle and a vehicle ahead is high. The computer program causes the computer to perform the following steps: The step of obtaining the predetermined direction of movement of the vehicle ahead; The step of prohibiting the execution of the collision avoidance control when the predetermined direction of movement of the vehicle ahead is the same as the predetermined direction of avoidance of the vehicle based on the collision avoidance control; and When the predetermined direction of movement of the vehicle ahead is different from the predetermined direction of avoidance of the vehicle based on the collision avoidance control, the step of setting the control start condition for starting the collision avoidance control is as follows: the control start condition is set at a later timing compared to the case where the predetermined direction of movement of the vehicle ahead is not acquired.

Images