Driving assistance device, driving assistance method, and driving assistance program

Abstract

To provide an operation support device capable of reliably avoiding a collision between an own vehicle and an object ahead thereof through forcibly causing the own vehicle to decelerate and make a turn.SOLUTION: An operation support device 10 executes: both side avoidance brake and steering control which forcibly causes an own vehicle to make a turn so as to avoid an object 200 while forcibly causing the own vehicle to decelerate with brake force applied to wheels on both sides of the own vehicle 100 when a turning amount increase demand condition is not met; and single side avoidance brake and steering control which forcibly causes the own vehicle to make a turn so as to avoid the object while forcibly causing the own vehicle to decelerate with the brake force applied to wheels on either a right side or a left side when the turning amount increase demand condition is met and the own vehicle is required to forcibly make a right turn or a left turn to avoid the object through collision avoidance control.SELECTED DRAWING: Figure 16

Description

[Technical field]

[0001] The present invention relates to a driving assistance device, a driving assistance method, and a driving assistance program. [Background technology]

[0002] There is known a driving support device that performs collision avoidance braking to avoid a collision between the host vehicle and the object ahead by forcibly decelerating the host vehicle and stopping the host vehicle before the host vehicle reaches the object ahead of the host vehicle. Furthermore, there is also known a driving support device that performs collision avoidance steering to avoid a collision between the host vehicle and the object ahead by forcibly turning the host vehicle so that the host vehicle runs while avoiding the object ahead in addition to the collision avoidance braking when the collision between the host vehicle and the object ahead cannot be avoided even after the collision avoidance braking is performed (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5246176 Summary of the Invention

[0004] In a conventional driving assistance device, when a collision between the host vehicle and the forward object cannot be avoided even by applying collision avoidance braking, the conventional driving assistance device attempts to avoid a collision between the host vehicle and the forward object by performing collision avoidance steering in addition to collision avoidance braking. In other words, the conventional driving assistance device attempts to avoid a collision between the host vehicle and the forward object by compensating for the part of the collision between the host vehicle and the forward object that cannot be avoided by collision avoidance braking with collision avoidance steering.

[0005] However, there is naturally a limit to the amount of lateral movement of the vehicle that can be achieved through collision avoidance steering, so there are some situations in which a collision between the vehicle and an object in front cannot be avoided simply by using collision avoidance steering to supplement collision avoidance braking.

[0006] An object of the present invention is to provide a driving assistance device, a driving assistance method, and a driving assistance program that can more reliably avoid a collision between the vehicle and an object ahead by forcibly decelerating the vehicle while turning.

[0007] The driving assistance device of the present invention is equipped with a control device that executes collision avoidance control to avoid a collision between the host vehicle and the object in front of the host vehicle by forcibly decelerating the host vehicle and forcibly turning the host vehicle so that the host vehicle travels while avoiding the object in front of the host vehicle.

[0008] In the driving assistance device of the present invention, when a turning amount increase request condition is not satisfied, which requests an increase in turning rate, which is the amount of turning of the host vehicle relative to the amount of change in the steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, the control device is configured to execute a two-sided braking steering avoidance control as the collision avoidance control, which applies equal or approximately equal braking forces to the wheels on both sides of the host vehicle to forcibly decelerate the host vehicle, while forcibly turning the host vehicle so that the host vehicle travels while avoiding the object.

[0009] Furthermore, in the driving assistance device according to the present invention, the control device is configured to execute, as the collision avoidance control, one-sided braking steering avoidance control for applying a greater braking force to a right wheel of the host vehicle than to a left wheel of the host vehicle to forcibly decelerate the host vehicle and forcibly turn the host vehicle so that the host vehicle runs while avoiding the object when the turning amount increase request condition is satisfied, while executing, as the collision avoidance control, one-sided braking steering avoidance control for applying a greater braking force to a left wheel of the host vehicle than to a right wheel of the host vehicle to forcibly decelerate the host vehicle and forcibly turn the host vehicle so that the host vehicle runs while avoiding the object when the turning amount increase request condition is satisfied, when the collision avoidance control is performed to forcibly turn the host vehicle so that the host vehicle runs while avoiding the object. The control device is configured to determine that, when a predetermined condition set based on the relative speed of the host vehicle with respect to the object or a predetermined condition set based on the overlap ratio between the host vehicle and the object is satisfied, there is a request to increase the turning rate, which is the amount of turning of the host vehicle relative to the amount of change in the steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, and to determine that the turning amount increase request condition is satisfied.

[0010] According to this, when there is a request to increase the turning rate when the host vehicle is forced to turn by the collision avoidance control, when the host vehicle is forced to turn and travel to avoid an object, a greater braking force is applied to the wheels on the side that turns the host vehicle than to the wheels on the opposite side, forcing the host vehicle to decelerate, so that the turning rate when the host vehicle turns becomes large. Therefore, when there is a request to increase the turning rate when the host vehicle is forced to turn by the collision avoidance control, the turning rate can be increased, and as a result, it becomes possible to more reliably avoid a collision between the host vehicle and the object ahead.

[0019] In addition, in the driving assistance device according to the present invention, The first predetermined condition For example, ,before written object The vehicle The relative velocity of is greater than a given velocity. With It is a condition.

[0020] When the vehicle is about to collide with an object ahead of the vehicle and the relative speed between the vehicle and the object is high, the vehicle needs to be turned widely in order to forcibly turn the vehicle to avoid the object and more reliably avoid the collision between the vehicle and the object. According to the present invention, when the vehicle is forcibly turned to avoid the object when the relative speed between the vehicle and the object is high, a larger braking force is applied to the wheels on the side turning the vehicle than to the wheels on the opposite side, forcibly slowing down the vehicle, so that the vehicle turns widely. Therefore, the collision between the vehicle and the object ahead of the vehicle can be more reliably avoided.

[0021] In addition, in the driving assistance device according to the present invention, The second predetermined condition For example, the overlap ratio between the host vehicle and the object is greater than a predetermined value. With It is a condition.

[0022] When the overlap ratio between the host vehicle and an object ahead of the host vehicle is large when the host vehicle is about to collide with the object, the host vehicle needs to be turned widely in order to forcibly turn the host vehicle to avoid the object and more reliably avoid the collision between the host vehicle and the object. According to the present invention, when the overlap ratio between the host vehicle and the object is large, when the host vehicle is forcibly turned to avoid the object, a larger braking force is applied to the wheels on the side turning the host vehicle than to the wheels on the opposite side, forcibly slowing down the host vehicle, so that the host vehicle makes a large turn. Therefore, the host vehicle can more reliably avoid the collision between the host vehicle and the object ahead.

[0023] In the driving assistance device according to the present invention, the collision avoidance control may include braking avoidance control for avoiding a collision between the host vehicle and the object by forcibly decelerating and stopping the host vehicle without forcibly turning the host vehicle. In this case, the control device may be configured to execute the braking avoidance control when the deceleration of the host vehicle when the braking avoidance control is executed is equal to or less than a predetermined deceleration, and to execute the two-sided braking steering avoidance control or the one-sided braking steering avoidance control when the deceleration of the host vehicle when the braking avoidance control is executed is greater than the predetermined deceleration.

[0024] According to this, if the deceleration of the host vehicle is large when the braking avoidance control is executed, the bilateral braking steering avoidance control or the one-sided braking steering avoidance control is executed, so that the host vehicle can be decelerated at a small deceleration while avoiding a collision between the host vehicle and an object.

[0025] In addition, in the driving assistance device of the present invention, the control device may be configured not to execute the both-side braking steering avoidance control and the one-side braking steering avoidance control if there is a possibility that the host vehicle will collide with an object other than the object when the both-side braking steering avoidance control or the one-side braking steering avoidance control is executed.

[0026] This makes it possible to prevent a collision between the host vehicle and another object that would otherwise be caused by executing both-side braking steering avoidance control or one-side braking steering avoidance control.

[0027] In addition, the driving assistance method according to the present invention is a method for avoiding a collision between the host vehicle and the object by forcibly decelerating the host vehicle and executing collision avoidance control that forcibly turns the host vehicle so that the host vehicle travels while avoiding the object in front of the host vehicle.

[0028] In the driving assistance method according to the present invention, when a turning amount increase request condition is not satisfied, which indicates that there is a request to increase a turning rate, which is a turning amount of the host vehicle relative to a change in steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, a two-sided braking steering avoidance control is executed as the collision avoidance control, in which equal or approximately equal braking forces are applied to wheels on both sides of the host vehicle to forcibly decelerate the host vehicle, and the host vehicle is forcibly turned so as to travel while avoiding the object, and when the turning amount increase request condition is satisfied, when the host vehicle is forcibly turned right by the collision avoidance control to travel while avoiding the object, The method executes one-sided braking steering avoidance control as the collision avoidance control, which applies a greater braking force to the right wheels of the vehicle than to the left wheels, thereby forcibly decelerating the vehicle, while forcibly turning the vehicle so that the vehicle runs away from the object, and when the turning amount increase request condition is satisfied, when the collision avoidance control forces the vehicle to turn left and run away from the object, the method executes one-sided braking steering avoidance control as the collision avoidance control, which applies a greater braking force to the left wheels of the vehicle than to the right wheels, thereby forcibly decelerating the vehicle, while forcibly turning the vehicle so that the vehicle runs away from the object. Furthermore, the driving assistance method is a method in which, when a first predetermined condition set based on the relative speed of the host vehicle with respect to the object or a second predetermined condition set based on the overlap ratio between the host vehicle and the object is satisfied, it is determined that there is a request to increase the turning rate, which is the amount of turning of the host vehicle relative to the amount of change in the steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, and the turning amount increase request condition is satisfied.

[0029] According to this, for the same reasons as those mentioned above, when there is a request to increase the turning rate when the vehicle is forcibly turned by collision avoidance control, the turning rate can be increased, and as a result, a collision between the vehicle and an object ahead can be avoided more reliably.

[0030] In addition, the driving assistance program of the present invention is a program that avoids a collision between the host vehicle and the object by forcibly decelerating the host vehicle and executing collision avoidance control that forcibly turns the host vehicle so that the host vehicle travels while avoiding the object in front of the host vehicle.

[0031] The driving assistance program according to the present invention executes, as the collision avoidance control, a bilateral braking steering avoidance control in which, when a turning amount increase request condition is not satisfied, the host vehicle is forcibly decelerated by applying equal or approximately equal braking forces to the wheels on both sides of the host vehicle, and the host vehicle is forcibly turned so as to travel while avoiding the object. When the turning amount increase request condition is satisfied, when the host vehicle is forcibly turned right by the collision avoidance control to travel while avoiding the object, the driving assistance program executes, as the collision avoidance control, a bilateral braking steering avoidance control in which the host vehicle is forcibly turned so as to travel while avoiding the object. The collision avoidance control is configured to execute one-sided braking steering avoidance control in which a greater braking force is applied to the right wheels of the host vehicle than to the left wheels, thereby forcibly decelerating the host vehicle, while forcibly turning the host vehicle so that the host vehicle runs away from the object, and when the turning amount increase request condition is satisfied, when the collision avoidance control is to forcibly turn the host vehicle left to run away from the object, the collision avoidance control is configured to execute one-sided braking steering avoidance control in which a greater braking force is applied to the left wheels of the host vehicle than to the right wheels, thereby forcibly decelerating the host vehicle, while forcibly turning the host vehicle so that the host vehicle runs away from the object. Furthermore, the driving assistance program is constructed so that, when a first predetermined condition set based on the relative speed of the host vehicle with respect to the object or a second predetermined condition set based on the overlap ratio between the host vehicle and the object is satisfied, it determines that there is a request to increase the turning rate, which is the amount of turning of the host vehicle relative to the amount of change in the steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, and determines that the turning amount increase request condition is satisfied.

[0032] According to this, for the same reasons as those mentioned above, when there is a request to increase the turning rate when the vehicle is forcibly turned by collision avoidance control, the turning rate can be increased, and as a result, a collision between the vehicle and an object ahead can be avoided more reliably.

[0035] The components of the present invention are not limited to the embodiments of the present invention described below with reference to the drawings. Other objects, other features and associated advantages of the present invention will be easily understood from the description of the embodiments of the present invention. [Brief description of the drawings]

[0036] [Figure 1] FIG. 1 is a diagram showing a driving assistance device according to an embodiment of the present invention and a vehicle (host vehicle) equipped with the driving assistance device. [Diagram 2] FIG. 2 is a diagram showing the distance between the vehicle and an object (vehicle) ahead of the vehicle. [Diagram 3] FIG. 3A is a diagram showing a predicted driving area of ​​the host vehicle, and FIG. 3B is a diagram showing a scene in which an object (vehicle) exists in the predicted driving area of ​​the host vehicle. [Figure 4] FIG. 4 is a diagram showing a scene in which the host vehicle approaches an object (vehicle) ahead of the host vehicle and a collision avoidance control execution condition is met. [Diagram 5] FIG. 5 is a diagram showing the relationship between the vehicle speed and the braking avoidance limit time and the steering avoidance limit time. [Figure 6] FIG. 6A is a diagram showing a scene in which a braking force is applied to the host vehicle by braking avoidance control, and FIG. 6B is a diagram showing a scene in which the host vehicle is stopped by braking avoidance control. [Figure 7] FIG. 7 is a diagram showing a scene in which the host vehicle approaches an object (vehicle) ahead of the host vehicle and the collision avoidance control execution condition is met. [Figure 8] FIG. 8(A) is a diagram showing a target driving route set by one-sided braking steering avoidance control, and FIG. 8(B) is a diagram showing a scene in which the host vehicle begins to turn along the target driving route by one-sided braking steering avoidance control. [Figure 9] FIG. 9(A) is a diagram showing a scene in which the host vehicle is passing alongside an object (vehicle) due to one-sided braking steering avoidance control, and FIG. 9(B) is a diagram showing a scene in which the host vehicle has passed alongside an object (vehicle) and one-sided braking steering avoidance control has ended. [Figure 10] FIG. 10A shows a target driving route set by both-side braking steering avoidance control, and FIG. 10B shows a scene in which the host vehicle begins to turn along the target driving route by both-side braking steering avoidance control. [Figure 11]FIG. 11(A) is a diagram showing a scene in which the host vehicle is passing alongside an object (vehicle) due to both-side braking steering avoidance control, and FIG. 11(B) is a diagram showing a scene in which the host vehicle has passed alongside an object (vehicle) and both-side braking steering avoidance control has ended. [Figure 12] Figure 12 (A) shows a situation where a following vehicle (a vehicle traveling behind the vehicle) is present when the collision avoidance control execution condition is met, and Figure 12 (B) shows a situation where the collision avoidance control execution condition is met for an object (person) about to cross the vehicle's lane. [Figure 13] FIG. 13(A) is a diagram showing a target driving route set by non-braking steering avoidance control, and FIG. 13(B) is a diagram showing a scene in which the host vehicle begins to turn along the target driving route by non-braking steering avoidance control. [Figure 14] FIG. 14A shows a scene in which the host vehicle passes beside an object (vehicle) due to non-braking steering avoidance control, and FIG. 14B shows a scene in which the host vehicle passes beside an object (vehicle) and non-braking steering avoidance control is terminated. [Figure 15] FIG. 15 is a diagram showing a scene in which another object (person) is present in the space beside a forward object (vehicle) with which a collision needs to be avoided. [Figure 16] FIG. 16 is a flowchart showing a routine executed by the driving assistance device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Hereinafter, a driving support device according to an embodiment of the present invention will be described with reference to the drawings. As shown in Fig. 1, a driving support device 10 according to an embodiment of the present invention is mounted on a vehicle (host vehicle 100).

[0038] <ecu> The driving assistance device 10 includes an ECU 90 as a control device. ECU is an abbreviation for electronic control unit. The ECU 90 includes a microcomputer as a main part. The microcomputer includes a CPU, ROM, RAM, non-volatile memory, and an interface. The CPU realizes various functions by executing instructions, programs, or routines stored in the ROM.

[0039] <Running gear> The host vehicle 100 is also equipped with a traveling device 20. The traveling device 20 includes a drive device 21, a braking device 22, and a steering device 23.

[0040] <Drive unit> The drive device 21 is a device that outputs a drive torque (drive force) applied to the host vehicle 100 to make the host vehicle 100 travel, and is, for example, an internal combustion engine, a motor, etc. The drive device 21 is electrically connected to the ECU 90. The ECU 90 can control the drive torque output from the drive device 21 by controlling the operation of the drive device 21.

[0041] <Brake device> The braking device 22 is a device that outputs a braking torque (braking force) applied to the host vehicle 100 in order to brake the host vehicle 100, and is, for example, a brake device. The braking device 22 is electrically connected to the ECU 90. The ECU 90 can control the braking torque output from the braking device 22, i.e., the braking torque applied to each wheel of the host vehicle 100 by the braking device 22, by controlling the operation of the braking device 22. In this example, the braking device 22 is configured to be able to individually control the braking torque applied to each wheel of the host vehicle 100.

[0042] <Steering system> The steering device 23 is a device that outputs a steering torque (steering force) applied to the host vehicle 100 in order to steer the host vehicle 100, and is, for example, a power steering device. The steering device 23 is electrically connected to the ECU 90. The ECU 90 can control the steering torque output from the steering device 23 by controlling the operation of the steering device 23, i.e., the steering torque applied to the host vehicle 100 by the steering device 23.

[0043] <Sensors, etc.> Furthermore, the vehicle 100 is equipped with an accelerator pedal 31, an accelerator pedal operation amount sensor 32, a brake pedal 33, a brake pedal operation amount sensor 34, a steering wheel 35, a steering shaft 36, a steering angle sensor 37, a steering torque sensor 38, a vehicle momentum detection device 50, and a surrounding information detection device 60.

[0044] <Accelerator pedal operation amount sensor> The accelerator pedal operation amount sensor 32 is a sensor that detects the amount of operation of the accelerator pedal 31. The accelerator pedal operation amount sensor 32 is electrically connected to the ECU 90. The accelerator pedal operation amount sensor 32 transmits information on the detected amount of operation of the accelerator pedal 31 to the ECU 90. Based on that information, the ECU 90 obtains the amount of operation of the accelerator pedal 31 as the accelerator pedal operation amount AP.

[0045] The ECU 90 acquires a required driving force (required driving torque) by calculation based on the accelerator pedal operation amount AP and the traveling speed of the host vehicle 100. The required driving force is a driving force that is required to be output from the drive device 21. The ECU 90 controls the operation of the drive device 21 so that the required driving force is output, except when executing braking avoidance control, one-sided braking steering avoidance control, and two-sided braking steering avoidance control, which will be described later.

[0046] <Brake pedal operation amount sensor> The brake pedal operation amount sensor 34 is a sensor that detects the amount of operation of the brake pedal 33. The brake pedal operation amount sensor 34 is electrically connected to the ECU 90. The brake pedal operation amount sensor 34 transmits information on the detected amount of operation of the brake pedal 33 to the ECU 90. The ECU 90 obtains the amount of operation of the brake pedal 33 as a brake pedal operation amount BP based on the information.

[0047] The ECU 90 acquires a required braking force (required braking torque) by calculation based on the brake pedal operation amount BP. The required braking force is a braking force that is required to be output from the braking device 22. The ECU 90 controls the operation of the braking device 22 so that the required braking force is output, except when executing braking avoidance control, one-sided braking steering avoidance control, and two-sided braking steering avoidance control, which will be described later.

[0048] <Steering angle sensor> The steering angle sensor 37 is a sensor that detects the rotation angle of the steering shaft 36 with respect to the neutral position. The steering angle sensor 37 is electrically connected to the ECU 90. The steering angle sensor 37 transmits information on the detected rotation angle of the steering shaft 36 to the ECU 90. The ECU 90 obtains the rotation angle of the steering shaft 36 as the steering angle θ based on the information.

[0049] <Steering torque sensor> The steering torque sensor 38 is a sensor that detects the torque input by the driver to the steering shaft 36 via the steering wheel 35. The steering torque sensor 38 is electrically connected to the ECU 90. The steering torque sensor 38 transmits information on the detected torque to the ECU 90. The ECU 90 acquires the torque input by the driver to the steering shaft 36 via the steering wheel 35 (driver input torque) based on the information.

[0050] <Vehicle motion detection device> The vehicle motion quantity detection device 50 is a device that detects the motion quantity of the host vehicle 100, and in this example, includes a vehicle speed detection device 51, a vertical acceleration sensor 52, a lateral acceleration sensor 53, and a yaw rate sensor .

[0051] <Vehicle speed detection device> The vehicle speed detection device 51 is a device that detects the traveling speed of the host vehicle 100, and is, for example, a wheel speed sensor. The vehicle speed detection device 51 is electrically connected to the ECU 90. The vehicle speed detection device 51 transmits information on the detected vehicle speed of the host vehicle 100 to the ECU 90. The ECU 90 acquires the traveling speed of the host vehicle 100 (host vehicle speed V100) based on the information.

[0052] The ECU 90 acquires a required steering force (required steering torque) by calculation based on the acquired steering angle θ, driver input torque, and vehicle speed V100. The required steering force is a steering force that is requested to be output from the steering device 23. The ECU 90 controls the operation of the steering device 23 so that the required steering force is output from the steering device 23, except when executing a side braking steering avoidance control and a both-side braking steering avoidance control, which will be described later.

[0053] <Vertical acceleration sensor> The vertical acceleration sensor 52 is a sensor that detects the acceleration in the forward / rearward direction of the host vehicle 100. The vertical acceleration sensor 52 is electrically connected to the ECU 90. The vertical acceleration sensor 52 transmits information on the detected acceleration to the ECU 90. The ECU 90 acquires the acceleration in the forward / rearward direction of the host vehicle 100 as the vertical acceleration Gx based on the information.

[0054] <Lateral acceleration sensor> The lateral acceleration sensor 53 is a sensor that detects the acceleration in the lateral direction (width direction) of the host vehicle 100. The lateral acceleration sensor 53 is electrically connected to the ECU 90. The lateral acceleration sensor 53 transmits information on the detected acceleration to the ECU 90. The ECU 90 obtains the lateral acceleration of the host vehicle 100 as the lateral acceleration Gy based on the information.

[0055] <Yaw rate sensor> The yaw rate sensor 54 is a sensor that detects the yaw rate YR of the host vehicle 100. The yaw rate sensor 54 is electrically connected to the ECU 90. The yaw rate sensor 54 transmits information on the detected yaw rate YR to the ECU 90. The ECU 90 acquires the yaw rate YR of the host vehicle 100 based on the information.

[0056] In addition, instead of the vertical acceleration sensor 52, the lateral acceleration sensor 53, and the yaw rate sensor 54, an IMU (Inertial Measurement Unit) in which the vertical acceleration sensor 52, the lateral acceleration sensor 53, and the yaw rate sensor 54 are integrated into one may be used.

[0057] <Peripheral information detection device> The surrounding information detection device 60 is a device that detects information about the surroundings of the vehicle 100, and in this example, includes a radio wave sensor 61 and an image sensor 62. The radio wave sensor 61 is, for example, a radar sensor (such as a millimeter wave radar). The image sensor 62 is, for example, a camera. The surrounding information detection device 60 may include a sonic sensor such as an ultrasonic sensor (clearance sonar) or an optical sensor such as a laser radar (LiDAR), or may include a ToF sensor (Time of Flight sensor).

[0058] <Radio wave sensor> The radio wave sensor 61 is electrically connected to the ECU 90. The radio wave sensor 61 transmits radio waves and receives radio waves reflected by objects (reflected waves). The radio wave sensor 61 transmits information (detection results) relating to the transmitted radio waves and received radio waves (reflected waves) to the ECU 90. In other words, the radio wave sensor 61 detects objects present in the vicinity of the vehicle 100 and transmits information (detection results) relating to the detected objects to the ECU 90. The ECU 90 can acquire information (periphery detection information ID) relating to objects present in the vicinity of the vehicle 100 based on the information (radio wave information).

[0059] In this example, the objects include vehicles, motorcycles, bicycles, and people.

[0060] <Image sensor> The image sensor 62 is also electrically connected to the ECU 90. The image sensor 62 captures an image of the surroundings of the vehicle 100, and transmits information related to the captured image to the ECU 90. The ECU 90 can acquire information (surroundings detection information ID) related to the surroundings of the vehicle 100 based on the information (image information).

[0061] 2, when an object (forward object 200) is present ahead of the vehicle 100, the ECU 90 detects the forward object 200 based on the surrounding detection information ID. The forward object 200 may be a vehicle, a motorcycle, a bicycle, a person, or the like, and is a vehicle in the example shown in FIG.

[0062] When the ECU 90 detects a forward object 200, it can obtain, for example, the "distance between the forward object 200 and the host vehicle 100 (object distance D200)" and the "speed of the host vehicle 100 relative to the forward object 200 (relative speed ΔV200)" based on the surrounding detection information ID.

[0063] Furthermore, the ECU 90 recognizes "the left and right demarcation lines LM_L and LM_R that define the driving lane of the vehicle 100 (the own lane LN1)" based on the surrounding detection information ID. The ECU 90 can specify the range of the own lane LN1 based on the recognized left and right demarcation lines LM (i.e., the left and right demarcation lines LM_L and LM_R). In FIG. 2, the symbol LN2 indicates an oncoming lane for the own lane LN1.

[0064] <Overview of operation of driving support device> Next, an overview of the operation of the driving support device 10 will be described.

[0065] <Normal driving control> While the host vehicle 100 is traveling, the driving support device 10 performs a process for detecting an object such as a vehicle ahead of the host vehicle 100 in the traveling direction based on the surrounding detection information ID. The driving support device 10 performs normal traveling control while the driving support device 10 does not detect an object ahead of the host vehicle 100 in the traveling direction.

[0066] Normal driving control is a control in which, when a required driving force is greater than zero, the operation of the drive device 21 is controlled so that the required driving force is output from the drive device 21, when a required braking force is greater than zero, the operation of the braking device 22 is controlled so that the required braking force is output from the braking device 22, and when a required steering force is greater than zero, the operation of the steering device 23 is controlled so that the required steering force is output from the steering device 23.

[0067] When the driving support device 10 detects an object ahead in the traveling direction of the vehicle 100, it determines whether or not the object (forward object 200) is present within the predicted traveling area A100. This determination is made based on the surrounding detection information ID.

[0068] As shown in Fig. 3A, the predicted travel area A100 is an area having a width equal to the width of the vehicle 100 and centered on the predicted travel route R100 of the vehicle 100. The predicted travel route R100 is a travel route that the vehicle 100 is predicted to travel in the future when the vehicle 100 travels while maintaining the steering angle θ at that time. Therefore, the predicted travel route R100 shown in Fig. 3A is a straight line, but depending on the situation, it may be a curved line.

[0069] When the detected forward object 200 does not exist within the predicted traveling area A100, the driving assistance device 10 continues the normal traveling control.

[0070] On the other hand, as shown in FIG. 3B, when the driving assistance device 10 determines that the detected forward object 200 is present within the predicted traveling area A100, it acquires a predicted arrival time TTC. The predicted arrival time TTC is a time that is predicted to be required for the host vehicle 100 to reach the forward object 200. The driving assistance device 10 acquires the predicted arrival time TTC by dividing the object distance D200 by the relative speed ΔV200 (TTC=D200 / ΔV200). While the driving assistance device 10 determines that the forward object 200 is present within the predicted traveling area A100, it acquires the object distance D200, the relative speed ΔV200, and the predicted arrival time TTC at a predetermined calculation cycle.

[0071] When the relative speed ΔV200 is constant, the predicted arrival time TTC becomes shorter as the host vehicle 100 approaches the forward object 200. Therefore, the predicted arrival time TTC is an index value representing the possibility that the host vehicle 100 will not collide with the forward object 200, and the index value becomes smaller as the predicted arrival time TTC becomes shorter and the possibility that the host vehicle 100 will not collide with the forward object 200 becomes smaller.

[0072] The driving support device 10 determines whether the predicted arrival time TTC has become shorter than a predetermined time (collision determination time TTCth). The driving support device 10 continues normal driving control while the predicted arrival time TTC is longer than the collision determination time TTCth.

[0073] 4, when the host vehicle 100 approaches the forward object 200 without the driver of the host vehicle 100 performing a collision avoidance steering operation (an operation applied to the steering wheel 35 to avoid a collision between the host vehicle 100 and the forward object 200) and the predicted arrival time TTC is shortened to the collision determination time TTCth, the driving assistance device 10 determines that the host vehicle 100 may collide with the forward object 200 if the host vehicle 100 is allowed to continue traveling as is. When the driving assistance device 10 determines that the host vehicle 100 may collide with the forward object 200, it determines that the collision avoidance control execution condition is satisfied.

[0074] <Collision avoidance control> When the driving support device 10 determines that the collision avoidance control execution condition is satisfied, it executes collision avoidance control to avoid a collision between the host vehicle 100 and the forward object 200. In this example, the collision avoidance control includes two controls, namely, braking avoidance control and steering avoidance control, and when the driving support device 10 determines that the collision avoidance control execution condition is satisfied, it executes either the braking avoidance control or the steering avoidance control to avoid a collision between the host vehicle 100 and the forward object 200.

[0075] In this example, the braking avoidance control is a control that forcibly decelerates the host vehicle 100 and stops it in front of the forward object 200. On the other hand, the steering avoidance control is a control that forcibly turns the host vehicle 100 so that the host vehicle 100 runs while avoiding the forward object 200, and more specifically, is a control that forcibly turns the host vehicle 100 so that the host vehicle 100 passes beside the forward object 200, and forcibly decelerates the host vehicle 100 as necessary.

[0076] The driving support device 10 executes braking avoidance control when the steering avoidance request condition is not satisfied, and executes steering avoidance control when the steering avoidance request condition is satisfied.

[0077] The steering avoidance request condition is set to, for example, a condition that the deceleration of the host vehicle 100 when the braking avoidance control is executed is greater than a predetermined deceleration. In this case, the predetermined deceleration may be, for example, the maximum deceleration of the host vehicle 100 that can be realized by the braking device 22, or the upper limit deceleration of the host vehicle 100 that can ensure the safety of the occupants of the host vehicle 100, including the driver.

[0078] Alternatively, the steering avoidance request condition is set to, for example, a condition that the braking force applied to the host vehicle 100 when the braking avoidance control is executed is greater than a predetermined braking force. In this case, the predetermined braking force may be, for example, a maximum value of the braking force that can be applied to the host vehicle 100 by the brake device 22, or an upper limit braking force that can ensure the safety of the occupants of the host vehicle 100, including the driver, when applied to the host vehicle 100.

[0079] However, in this example, the steering avoidance requirement condition is set as follows.

[0080] The minimum predicted arrival time TTC (braking avoidance limit time TTC_B) at which a collision between the host vehicle 100 and the forward object 200 can be avoided by braking avoidance control increases as the host vehicle speed V100 increases, as shown by line TTB in Fig. 5. Also, the minimum predicted arrival time TTC (steering avoidance limit time TTC_S) at which a collision between the host vehicle 100 and the forward object 200 can be avoided by steering avoidance control without deceleration of the host vehicle 100 decreases as the host vehicle speed V100 increases, as shown by line TTS in Fig. 5. Also, line TTB (a line showing the relationship between braking avoidance limit time TTC_B and the host vehicle speed V100) and line TTS (a line showing the relationship between steering avoidance limit time TTC_S and the host vehicle speed V100) intersect at a certain vehicle speed Vth. Therefore, the magnitude relationship between the braking avoidance limit time TTC_B and the steering avoidance limit time TTC_S is reversed at a certain vehicle speed Vth. Specifically, when the host vehicle speed V100 is smaller than a certain vehicle speed Vth, the braking avoidance limit time TTC_B is shorter than the steering avoidance limit time TTC_S, and when the host vehicle speed V100 is greater than a certain vehicle speed Vth, the steering avoidance limit time TTC_S is shorter than the braking avoidance limit time TTC_B.

[0081] This means that when the host vehicle speed V100 is relatively low, collision avoidance control does not need to be started until a later time when avoiding a collision between the host vehicle 100 and the forward object 200 by braking avoidance control rather than by steering avoidance control. On the other hand, when the host vehicle speed V100 is relatively high, collision avoidance control does not need to be started until a later time when avoiding a collision between the host vehicle 100 and the forward object 200 by steering avoidance control rather than by braking avoidance control.

[0082] Here, when the braking avoidance control or the steering avoidance control is started, some drivers may feel that the timing of starting the braking avoidance control or the steering avoidance control is too early. Therefore, even if the braking avoidance control or the operation avoidance control is started, it is preferable to start it as late as possible.

[0083] From the above, the driving support device 10 is configured to set either the braking avoidance limit time TTC_B or the steering avoidance limit time TTC_S as the collision determination time TTCth according to the host vehicle speed V100. Specifically, when the host vehicle speed V100 is smaller than a certain vehicle speed Vth (predetermined vehicle speed Vth), the driving support device 10 sets the braking avoidance limit time TTC_B as the collision determination time TTCth, and when the host vehicle speed V100 is larger than the predetermined vehicle speed Vth, the driving support device 10 sets the steering avoidance limit time TTC_S as the collision determination time TTCth. In addition, when the host vehicle speed V100 is equal to the predetermined vehicle speed Vth, either the braking avoidance limit time TTC_B or the steering avoidance limit time TTC_S may be set as the collision determination time TTCth, but in this example, the driving support device 10 is configured to set the braking avoidance limit time TTC_B as the collision determination time TTCth.

[0084] Then, the driving assistance device 10 determines that the steering avoidance request condition is satisfied if the vehicle speed V100 at that time is greater than a predetermined vehicle speed Vth, or determines that the steering avoidance request condition is satisfied if the steering avoidance limit time TTC_S corresponding to the vehicle speed V100 at that time is shorter than the braking avoidance limit time TTC_B corresponding to the vehicle speed V100 at that time.

[0085] That is, in this example, the steering avoidance request condition is a condition that the vehicle speed V100 at that time is greater than a predetermined vehicle speed Vth, or a condition that the steering avoidance limit time TTC_S corresponding to the vehicle speed V100 at that time is shorter than the braking avoidance limit time TTC_B corresponding to the vehicle speed V100 at that time.

[0086] <Braking Avoidance Control> When the steering avoidance request condition is not satisfied, the driving support device 10 starts braking avoidance control and forcibly applies a braking force to the host vehicle 100 as shown in Fig. 6(A). This causes the host vehicle 100 to stop in front of the forward object 200 as shown in Fig. 6(B).

[0087] This makes it possible to avoid a collision between the host vehicle 100 and the forward object 200.

[0088] On the other hand, when the steering avoidance requirement condition is satisfied, the driving support device 10 determines whether or not the turning amount increase requirement condition is satisfied.

[0089] <Requirements for increasing turning volume> For example, as shown in FIG. 7, when the collision avoidance control execution condition is met, there is a space to the right of the forward object 200 in which the host vehicle 100 can travel. Therefore, when attempting to avoid a collision between the host vehicle 100 and the forward object 200 by having the host vehicle 100 pass through the space to the right of the forward object 200, if the forward object 200 begins to move to the right, it may be impossible to avoid the collision between the host vehicle 100 and the forward object 200 unless the host vehicle 100 is made to make a large right turn.

[0090] In such a case, it is preferable to increase the amount of turning of the host vehicle 100 (the turning rate of the host vehicle 100) relative to the amount of change in the steering angle of the host vehicle 100 when the host vehicle 100 is forcibly turned by collision avoidance control.

[0091] In this example, the condition for requesting an increase in turning amount is a condition that there is a request to increase the turning amount (turning rate of the vehicle 100) of the vehicle 100 relative to the change in steering angle of the vehicle 100 when the vehicle 100 is forcibly turned by collision avoidance control, and in particular, a condition that the vehicle 100 cannot be driven to avoid the object 200 in front using the two-sided braking steering avoidance control described later.

[0092] In this example, the turning amount increase requirement condition is set to a condition that the turning rate of the host vehicle 100 required for driving the host vehicle 100 so as to avoid the forward object 200 is greater than a predetermined turning rate. Also, in this example, the predetermined turning rate is set to the maximum value of the turning rate of the host vehicle 100 that can be achieved by the both-side braking steering avoidance control described later.

[0093] The turning amount increase request condition may be set to a condition that the turning amount of the host vehicle 100 achievable by the bilateral braking steering avoidance control described later is smaller than the turning amount of the host vehicle 100 required to drive the host vehicle 100 so as to avoid the forward object 200, or that the relative speed ΔV200 between the host vehicle 100 and the forward object 200 is greater than a predetermined speed, or that the overlap ratio between the host vehicle 100 and the forward object 200 is greater than a predetermined value. The overlap ratio between the host vehicle 100 and the forward object 200 is a value indicating the ratio of the vehicle width of the host vehicle 100 overlapping the width of the forward object 200 relative to the vehicle width of the host vehicle 100.

[0094] Alternatively, the turning amount increase request condition may be set to a condition that the object ahead 200 starts to move to the right when the host vehicle 100 is turned right and traveling due to collision avoidance control so that the host vehicle 100 passes to the right of the object ahead 200, or that the object ahead 200 starts to move to the left when the host vehicle 100 is turned left and traveling due to collision avoidance control so that the host vehicle 100 passes to the left of the object ahead 200. The determination of whether the object ahead 200 has started to move to the right and the determination of whether the object ahead 200 has moved to the left are made based on the surrounding detection information ID.

[0095] <Steering avoidance control> In this example, the steering avoidance control includes two types of control: two-sided braking steering avoidance control and one-sided braking steering avoidance control.

[0096] <Two-sided steering avoidance control> The two-sided braking steering avoidance control is a control that forcibly slows down the vehicle 100 by applying equal or approximately equal (the difference is within a range smaller than a predetermined value) braking forces to the wheels on both sides of the vehicle 100, while forcibly turning the vehicle 100 so that the vehicle 100 travels while avoiding the object 200 ahead.

[0097] In particular, in this example, the bilateral braking steering avoidance control is a control that applies equal braking forces to the wheels on both the left and right sides of the host vehicle 100, respectively, to forcibly decelerate the host vehicle 100, while applying a steering force to the host vehicle 100 to forcibly turn the host vehicle 100 so that the host vehicle 100 runs while avoiding the forward object 200. In particular, the bilateral braking steering avoidance control is a control that applies equal braking forces to the wheels on both the left and right sides of the host vehicle 100, respectively, to forcibly decelerate the host vehicle 100, while applying a steering force to the host vehicle 100 to forcibly turn the host vehicle 100 so that the host vehicle 100 passes beside the forward object 200.

[0098] <One-sided braking and steering avoidance control> On the other hand, one-sided braking steering avoidance control is a control that applies a greater braking force to the wheels of the vehicle 100 on the side that is forcing the vehicle 100 to turn than to the wheels on the opposite side, thereby forcibly slowing down the vehicle 100 and forcibly turning the vehicle 100 so that the vehicle 100 runs while avoiding the object 200 in front. In other words, the one-sided braking steering avoidance control is a control in which, when the host vehicle 100 is forced to turn right to avoid the object 200 ahead, a greater braking force (or a braking force greater than a predetermined value) is applied to the right wheels of the host vehicle 100 than to the left wheels, forcibly slowing down the host vehicle 100 while forcibly turning the host vehicle 100 so that the host vehicle 100 runs while avoiding the object 200 ahead, and, when the host vehicle 100 is forced to turn left to avoid the object 200 ahead, a greater braking force (or a braking force greater than a predetermined value) is applied to the left wheels of the host vehicle 100 than to the right wheels, forcibly slowing down the host vehicle 100 while forcibly turning the host vehicle 100 so that the host vehicle 100 runs while avoiding the object 200 ahead.

[0099] In particular, in this example, the one-sided braking steering avoidance control is a control that applies braking force to only one of the left or right wheels of the vehicle 100 to forcibly decelerate the vehicle 100, while applying a steering force to the vehicle 100 to forcibly turn the vehicle 100 so that it passes next to the object 200 in front. In other words, the one-sided braking steering avoidance control is a control in which, when the host vehicle 100 is forced to turn right to avoid the object 200 ahead, braking force is applied only to the right wheels of the host vehicle 100 to forcibly decelerate the host vehicle 100 while forcibly turning the host vehicle 100 so that the host vehicle 100 runs while avoiding the object 200 ahead, and, when the host vehicle 100 is forced to turn left to avoid the object 200 ahead, braking force is applied only to the left wheels of the host vehicle 100 to forcibly decelerate the host vehicle 100 while forcibly turning the host vehicle 100 so that the host vehicle 100 runs while avoiding the object 200 ahead.

[0100] Therefore, when the driving assistance device 10 forcibly turns the host vehicle 100 by one-sided braking steering avoidance control so that the host vehicle 100 passes to the right of the forward object 200, the driving assistance device 10 forcibly turns the host vehicle 100 while applying braking force only to the right wheels of the host vehicle 100, without applying braking force to the left wheels of the host vehicle 100. According to this, when one-sided braking steering avoidance control is started to forcibly turn the host vehicle 100 to the right, braking force is applied only to the right wheels of the host vehicle 100, so that the host vehicle 100 can make a large right turn.

[0101] On the other hand, when the driving assistance device 10 forcibly turns the host vehicle 100 by one-sided braking steering avoidance control so that the host vehicle 100 passes to the left of the forward object 200, the driving assistance device 10 forcibly turns the host vehicle 100 while applying braking force only to the left wheels of the host vehicle 100, without applying braking force to the right wheels of the host vehicle 100. According to this, when the one-sided braking steering avoidance control is started to forcibly turn the host vehicle 100 to the left, braking force is applied only to the left wheels of the host vehicle 100, so that the host vehicle 100 can make a large left turn.

[0102] <Execution of one-sided braking and steering avoidance control> The driving support device 10 executes one-sided braking steering avoidance control when the turning amount increase request condition is satisfied. When the driving support device 10 starts one-sided braking steering avoidance control, as shown in (A) of Fig. 8, if there is a space for the host vehicle 100 to travel on the right side of the forward object 200, the driving support device 10 sets a route that passes by the right side of the forward object 200 as the route for the host vehicle 100 to travel (target driving route Rtgt). On the other hand, if there is a space for the host vehicle 100 to travel on the left side of the forward object 200, the driving support device 10 sets a route that passes by the left side of the forward object 200 as the route for the host vehicle 100 to travel (target driving route Rtgt).

[0103] Then, as shown in FIG. 8B, the driving assistance device 10 starts to apply a steering force to the host vehicle 100 while applying a braking force only to the wheels on one side of the host vehicle 100 so that the host vehicle 100 travels along the target travel route Rtgt.

[0104] As a result, as shown in Fig. 9(A), the host vehicle 100 passes beside the forward object 200, and as shown in Fig. 9(B), the host vehicle 100 passes beside the forward object 200. This avoids a collision between the host vehicle 100 and the forward object 200. Then, when the host vehicle 100 passes beside the forward object 200, the driving assistance device 10 ends the one-side braking steering avoidance control.

[0105] This makes it possible to avoid a collision between the host vehicle 100 and the forward object 200 even in a situation where a turning amount increase requirement condition is met.

[0106] In addition, when executing one-sided braking steering avoidance control so that the host vehicle 100 passes to the right of the forward object 200, the driving support device 10 is configured not to apply a braking force to the host vehicle 100 after the host vehicle 100 is forcibly turned right and then turned left (when the steering angle is turned back), but may be configured, for example, to apply a braking force only to the left wheels of the host vehicle 100 when turning left. Similarly, when executing one-sided braking steering avoidance control so that the host vehicle 100 passes to the left of the forward object 200, the driving support device 10 is configured not to apply a braking force to the host vehicle 100 after the host vehicle 100 is forcibly turned left and then turned right (when the steering angle is turned back), but may be configured, for example, to apply a braking force only to the right wheels of the host vehicle 100 when turning right.

[0107] <Execution of both-side braking and steering avoidance control> On the other hand, when the turning amount increase request condition is not satisfied, the driving support device 10 executes both-side braking steering avoidance control. When the driving support device 10 starts both-side braking steering avoidance control, as shown in Fig. 10(A), if there is a space for the host vehicle 100 to travel on the right side of the forward object 200, the driving support device 10 sets a route that passes by the right side of the forward object 200 as the route for the host vehicle 100 to travel (target driving route Rtgt). On the other hand, if there is a space for the host vehicle 100 to travel on the left side of the forward object 200, the driving support device 10 sets a route that passes by the left side of the forward object 200 as the route for the host vehicle 100 to travel (target driving route Rtgt).

[0108] Then, as shown in FIG. 10B, the driving assistance device 10 starts to apply a steering force to the host vehicle 100 while applying a braking force to the wheels on both sides of the host vehicle 100 so that the host vehicle 100 travels along the target travel route Rtgt.

[0109] As a result, as shown in Fig. 11(A), the host vehicle 100 passes beside the forward object 200, and as shown in Fig. 11(B), the host vehicle 100 passes beside the forward object 200. This avoids a collision between the host vehicle 100 and the forward object 200. Then, when the host vehicle 100 passes beside the forward object 200, the driving assistance device 10 ends the both-side braking steering avoidance control. Note that when the both-side braking steering avoidance control is executed, the host vehicle 100 is stopped when it reaches the space beside the forward object 200.

[0110] This makes it possible to avoid a collision between the host vehicle 100 and the forward object 200 .

[0111] <Non-braking steering avoidance control> Furthermore, as shown in (A) of Figure 12, when there is a vehicle (following vehicle 300) traveling behind the host vehicle 100 and the distance between the following vehicle 300 and the host vehicle 100 is shorter than a predetermined distance, if steering avoidance control involving deceleration of the host vehicle 100, such as one-sided braking steering avoidance control or two-sided braking steering avoidance control, is executed, there is a possibility that the following vehicle 300 will collide with the host vehicle 100 from behind.

[0112] Furthermore, as shown in (B) of FIG. 12, if the forward object 200 is an object such as a person moving laterally relative to the vehicle's lane LN1, if steering avoidance control involving deceleration of the vehicle 100, such as one-sided braking steering avoidance control or two-sided braking steering avoidance control, is executed, there is a possibility that the vehicle 100 will collide with the forward object 200 depending on the moving speed of the forward object 200.

[0113] Therefore, the driving assistance device 10 may be configured to execute non-braking steering avoidance control when the braking prohibition condition is satisfied in a case where the steering avoidance request condition is satisfied.

[0114] Non-braking steering avoidance control is a control that forcibly turns the host vehicle 100 so that the host vehicle 100 passes beside the object 200 ahead by forcibly applying a steering force to the host vehicle 100 without applying a braking force to the host vehicle 100.

[0115] In addition, the braking prohibition condition is a condition for prohibiting the execution of steering avoidance control (one-sided braking steering avoidance control and two-sided braking steering avoidance control) involving the application of braking force to the host vehicle 100, and is, for example, a condition that there is a possibility that the following vehicle 300 will rear-end the host vehicle 100 if steering avoidance control (one-sided braking steering avoidance control and two-sided braking steering avoidance control) involving the application of braking force to the host vehicle 100 is executed, and / or a condition that there is a possibility that the host vehicle 100 will collide with the forward object 200 if steering avoidance control (one-sided braking steering avoidance control and two-sided braking steering avoidance control) involving the application of braking force to the host vehicle 100 is executed, but the host vehicle 100 can be made to travel so as to pass beside the forward object 200 if deceleration of the host vehicle 100 is not involved.

[0116] In addition, the determination of whether or not there is a possibility that the following vehicle 300 will rear-end the host vehicle 100 when steering avoidance control involving the application of a braking force to the host vehicle 100, and the determination of whether or not there is a possibility that the host vehicle 100 will collide with the object ahead 200 when steering avoidance control involving the application of a braking force to the host vehicle 100 is executed, but whether or not the host vehicle 100 can be driven to pass beside the object ahead 200 without decelerating the host vehicle 100, are performed based on the surrounding detection information ID.

[0117] 13A, when the driving assistance device 10 starts the non-braking steering avoidance control, if there is a space for the host vehicle 100 to travel on the right side of the forward object 200, the driving assistance device 10 sets a route that passes by the right side of the forward object 200 as the route for the host vehicle 100 to travel (target driving route Rtgt). On the other hand, if there is a space for the host vehicle 100 to travel on the left side of the forward object 200, the driving assistance device 10 sets a route that passes by the left side of the forward object 200 as the route for the host vehicle 100 to travel (target driving route Rtgt).

[0118] 13B, the driving support device 10 starts to apply a steering force to the host vehicle 100 so that the host vehicle 100 travels along the target travel route Rtgt. At this time, the driving support device 10 does not apply a braking force to the host vehicle 100.

[0119] As a result, as shown in Fig. 14(A), the host vehicle 100 passes beside the forward object 200, and as shown in Fig. 14(B), the host vehicle 100 passes beside the forward object 200. This avoids a collision between the host vehicle 100 and the forward object 200. Then, when the host vehicle 100 passes beside the forward object 200, the driving assistance device 10 ends the non-braking steering avoidance control.

[0120] This makes it possible to avoid a collision between the host vehicle 100 and the forward object 200 even in a situation where a braking prohibition condition is met.

[0121] <Conditions for prohibiting steering avoidance> 15, when steering avoidance control (one-sided braking steering avoidance control, two-sided braking steering avoidance control, and non-braking steering avoidance control) is executed in a situation where an object such as a person (secondary object 400) is present in the space to the side of the forward object 200, if the target driving route Rtgt is set to pass through the space in which the secondary object 400 is present and the host vehicle 100 travels along the target driving route Rtgt, the host vehicle 100 will collide with the secondary object 400. In such a case, it is not preferable to execute steering avoidance control.

[0122] Therefore, the driving assistance device 10 may be configured to execute braking avoidance control instead of executing steering avoidance control when the steering avoidance prohibition condition is satisfied, even if the steering avoidance request condition is satisfied.

[0123] This makes it possible to avoid a collision between the host vehicle 100 and the forward object 200 even in a situation where the steering avoidance prohibition condition is met.

[0124] <Lane change collision avoidance control> Furthermore, when attempting to avoid a collision between the host vehicle 100 and the forward object 200 by steering avoidance control, there may be no space within the host lane LN1 that is large enough for the host vehicle 100 to pass beside the forward object 200. In this case, when attempting to avoid a collision between the host vehicle 100 and the forward object 200 by steering avoidance control and there is no space within the host lane LN1 that is large enough for the host vehicle 100 to pass beside the forward object 200, if there is a parallel lane adjacent to the host lane LN1, the driving assistance device 10 may be configured to execute lane change collision avoidance control to change the host vehicle 100 to the parallel lane, on the condition that safety in lane change of the host vehicle 100 to the parallel lane (the host vehicle 100 does not come into contact with another vehicle traveling on the parallel lane) is ensured.

[0125] According to this, even when attempting to avoid a collision between the vehicle 100 and the object ahead 200 by using steering avoidance control, a collision between the vehicle 100 and the object ahead 200 can be avoided even in a situation where there is not enough space within the vehicle lane LN1 to allow the vehicle 100 to pass next to the object ahead 200.

[0126] <Specific operation of the driving support device> Next, a specific operation of the driving support device 10 will be described. The CPU of the ECU 90 of the driving support device 10 according to the embodiment of the present invention is configured to execute the routine shown in Fig. 16 at a predetermined calculation cycle. Therefore, at a predetermined timing, the CPU starts processing from step 1600 of the routine shown in Fig. 16, advances the processing to step 1605, and determines whether or not a collision avoidance control execution condition is satisfied.

[0127] If the CPU judges "Yes" in step 1605, the process proceeds to step 1610, where it judges whether or not the steering avoidance request condition is satisfied. If the CPU judges "Yes" in step 1610, the process proceeds to step 1615, where it judges whether or not the braking prohibition condition is satisfied. If the CPU judges "No" in step 1615, the process proceeds to step 1620, where it judges whether or not the steering avoidance prohibition condition is satisfied. If the CPU judges "No" in step 1620, the process proceeds to step 1625, where it judges whether or not the turning amount increase request condition is satisfied. If the CPU judges "Yes" in step 1625, the process proceeds to step 1630, where it executes one-sided braking steering avoidance control. Next, the CPU proceeds to step 1655.

[0128] On the other hand, if the CPU determines "No" in step 1635, the CPU proceeds to step 1635 and executes both-side braking steering avoidance control.

[0129] If the CPU determines "Yes" in step 1620, the process proceeds to step 1650, where it executes braking avoidance control.

[0130] If the CPU determines "Yes" in step 1615, the process proceeds to step 1645, where it executes non-braking steering avoidance control.

[0131] If the CPU determines "No" in step 1610, the process proceeds to step 1640, where it executes braking avoidance control.

[0132] When the CPU advances the process to step 1655, it determines whether or not avoidance of a collision between the host vehicle 100 and the forward object 200 by the collision avoidance control has been completed. When the CPU determines "Yes" in step 1655, it advances the process to step 1660 and stops the collision avoidance control being executed. Next, the CPU advances the process to step 1695 and temporarily ends the processing of this routine.

[0133] On the other hand, if the CPU determines "No" in step 1655, it proceeds directly to step 1695 and temporarily ends the processing of this routine.

[0134] If the CPU determines "No" in step 1605, the CPU proceeds directly to step 1695 and temporarily ends the processing of this routine.

[0135] The specific operation of the driving assistance device 10 has been described above.

[0136] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. [Explanation of symbols]

[0137] 10...driving assistance device, 20...running device, 22...braking device, 23...steering device, 60...peripheral information detection device, 90...ECU, 100...own vehicle, 200...forward vehicle, 300...following vehicle< / ecu>

Claims

1. A driving assistance device including a control device that executes collision avoidance control to avoid a collision between a host vehicle and an object in front of the host vehicle by forcibly decelerating the host vehicle and forcibly turning the host vehicle so that the host vehicle runs while avoiding the object in front of the host vehicle, The control device includes: when a turning amount increase request condition is not satisfied, which is a request to increase a turning rate, which is a turning amount of the host vehicle relative to a change in steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, a both-side braking steering avoidance control is executed as the collision avoidance control, which applies equal or approximately equal braking forces to the wheels on both sides of the host vehicle, respectively, to forcibly decelerate the host vehicle, and forcibly turns the host vehicle so that the host vehicle travels while avoiding the object, When the turning amount increase request condition is satisfied, when the host vehicle is forced to turn right by the collision avoidance control to avoid the object, a one-sided braking steering avoidance control is executed as the collision avoidance control, in which a greater braking force is applied to a right wheel of the host vehicle than to a left wheel of the host vehicle to forcibly decelerate the host vehicle, while the host vehicle is forced to turn so as to avoid the object, When the turning amount increase request condition is satisfied, when the host vehicle is forced to turn left by the collision avoidance control to run so as to avoid the object, a one-sided braking steering avoidance control is executed as the collision avoidance control, in which a braking force greater than that applied to a right wheel of the host vehicle is applied to the left wheel of the host vehicle to forcibly decelerate the host vehicle, while the host vehicle is forced to turn so as to run so as to avoid the object. It is configured as follows: In the driving assistance device, The control device is configured to determine that there is a request to increase a turning rate, which is an amount of turning of the host vehicle relative to an amount of change in a steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, when a first predetermined condition set based on a relative speed of the host vehicle with respect to the object or a second predetermined condition set based on an overlap ratio between the host vehicle and the object is satisfied, and to determine that the turning amount increase request condition is satisfied. Driving assistance device.

2. The driving assistance device according to claim 1, The first predetermined condition is a condition that a relative speed of the host vehicle with respect to the object is greater than a predetermined speed. Driving assistance device.

3. The driving assistance device according to claim 1, The second predetermined condition is a condition that an overlap ratio between the host vehicle and the object is greater than a predetermined value. Driving assistance device.

4. A driving assistance device according to any one of claims 1 to 3, the collision avoidance control includes a braking avoidance control for forcibly decelerating and stopping the host vehicle without forcibly turning the host vehicle, thereby avoiding a collision between the host vehicle and the object, The control device includes: When the deceleration of the host vehicle when the braking avoidance control is executed is equal to or less than a predetermined deceleration, the braking avoidance control is executed; When the deceleration of the host vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, the both-side braking steering avoidance control or the one-side braking steering avoidance control is executed. It is configured as follows: Driving assistance device.

5. A driving assistance device according to any one of claims 1 to 3, The control device is configured not to execute the both-side braking steering avoidance control and the one-side braking steering avoidance control when there is a possibility that the host vehicle will collide with an object other than the object when the both-side braking steering avoidance control or the one-side braking steering avoidance control is executed. Driving assistance device.

6. A driving assistance method for avoiding a collision between a host vehicle and an object in front of the host vehicle by executing a collision avoidance control that forcibly decelerates the host vehicle and forcibly turns the host vehicle so that the host vehicle travels while avoiding the object in front of the host vehicle, comprising: when a turning amount increase request condition is not satisfied, which is a request to increase a turning rate, which is a turning amount of the host vehicle relative to a change in steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, a both-side braking steering avoidance control is executed as the collision avoidance control, which applies equal or approximately equal braking forces to the wheels on both sides of the host vehicle, respectively, to forcibly decelerate the host vehicle, and forcibly turns the host vehicle so that the host vehicle travels while avoiding the object, When the turning amount increase request condition is satisfied, when the host vehicle is forced to turn right by the collision avoidance control to avoid the object, a one-sided braking steering avoidance control is executed as the collision avoidance control, in which a greater braking force is applied to a right wheel of the host vehicle than to a left wheel of the host vehicle to forcibly decelerate the host vehicle, while the host vehicle is forced to turn so as to avoid the object, When the turning amount increase request condition is satisfied, when the host vehicle is forced to turn left by the collision avoidance control to run so as to avoid the object, a one-sided braking steering avoidance control is executed as the collision avoidance control, in which a braking force greater than that applied to a right wheel of the host vehicle is applied to the left wheel of the host vehicle to forcibly decelerate the host vehicle, while the host vehicle is forced to turn so as to run so as to avoid the object. In the driving assistance method, When a first predetermined condition set based on a relative speed of the host vehicle with respect to the object or a second predetermined condition set based on an overlap ratio between the host vehicle and the object is satisfied, it is determined that there is a request to increase a turning rate, which is an amount of turning of the host vehicle relative to an amount of change in the steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, and it is determined that the turning amount increase request condition is satisfied. Driving assistance methods.

7. A driving assistance program for avoiding a collision between a host vehicle and an object in front of the host vehicle by executing a collision avoidance control for forcibly decelerating the host vehicle and forcibly turning the host vehicle so as to avoid the object in front of the host vehicle, when a turning amount increase request condition is not satisfied, which is a request to increase a turning rate, which is a turning amount of the host vehicle relative to a change in steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, a both-side braking steering avoidance control is executed as the collision avoidance control, which applies equal or approximately equal braking forces to the wheels on both sides of the host vehicle, respectively, to forcibly decelerate the host vehicle, and forcibly turns the host vehicle so that the host vehicle travels while avoiding the object, When the turning amount increase request condition is satisfied, when the host vehicle is forced to turn right by the collision avoidance control to avoid the object, a one-sided braking steering avoidance control is executed as the collision avoidance control, in which a greater braking force is applied to a right wheel of the host vehicle than to a left wheel of the host vehicle to forcibly decelerate the host vehicle, while the host vehicle is forced to turn so as to avoid the object, When the turning amount increase request condition is satisfied, when the host vehicle is forced to turn left by the collision avoidance control to run so as to avoid the object, a one-sided braking steering avoidance control is executed as the collision avoidance control, in which a braking force greater than that applied to a right wheel of the host vehicle is applied to the left wheel of the host vehicle to forcibly decelerate the host vehicle, while the host vehicle is forced to turn so as to run so as to avoid the object. In a driving assistance program that is constructed in such a way that A driving assistance program constructed to determine that, when a first predetermined condition set based on the relative speed of the host vehicle with respect to the object or a second predetermined condition set based on the overlap ratio between the host vehicle and the object is satisfied, there is a request to increase the turning rate, which is the amount of turning of the host vehicle relative to the amount of change in the steering angle of the host vehicle when the host vehicle is forcibly turned by the collision avoidance control, and to determine that the turning amount increase request condition is satisfied.

Images