Driver assistance device, driver assistance method, and driver assistance program

Abstract

To provide a driving assistance device capable of avoiding the collision between a vehicle itself and a forward object more reliably by forcibly decelerating and turning the vehicle itself.SOLUTION: A driving assistance device 10 is configured to: when a deceleration during execution of braking avoidance control is equal to or lower than a predetermined deceleration, execute the braking avoidance control; meanwhile, when the deceleration is higher than the predetermined deceleration and a turning amount increase request condition is not satisfied, execute dual-side braking steering avoidance control; meanwhile, when the deceleration is higher than the predetermined deceleration, the turning amount increase request condition is satisfied, and in addition, when intending to turn a vehicle itself 100 rightward to avoid an object, execute first single-side braking steering avoidance control; and when the deceleration is higher than the predetermined deceleration, the turning amount increase request condition is satisfied, and in addition, when intending to turn the vehicle itself leftward to avoid the object, execute second single-side braking steering avoidance control.SELECTED DRAWING: Figure 16

Description

Technical Field

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

Background Art

[0002] There is known a driving support device that performs collision avoidance braking to avoid a collision between the host vehicle and a forward object by forcibly decelerating the host vehicle and stopping the host vehicle before it reaches the forward object in front of it. Further, when it is not possible to avoid a collision between the host vehicle and the forward object even by performing collision avoidance braking, there is also known a driving support device that performs collision avoidance steering to avoid a collision between the host vehicle and the forward object by forcibly turning the host vehicle so that the host vehicle travels while avoiding the forward object (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] Conventional driving support devices attempt to avoid a collision between the host vehicle and a forward object by performing collision avoidance steering in addition to collision avoidance braking when it is not possible to avoid a collision between the host vehicle and the forward object even by performing collision avoidance braking. In other words, conventional driving support devices attempt to avoid a collision between the host vehicle and the forward object by supplementing what cannot be avoided by collision avoidance braking with collision avoidance steering.

[0005] However, there is a limit to the amount of lateral movement of the host vehicle that can be achieved by collision avoidance steering. Therefore, there are also situations where it is not possible to avoid a collision between the host vehicle and the forward object simply by using collision avoidance steering to supplement collision avoidance braking.

[0006] The object of the present invention is to provide a driver assistance device, a driver assistance method, and a driver assistance program that can more reliably avoid a collision between the vehicle and an object in front of it by forcibly decelerating and turning the vehicle.

[0007] The driver assistance system according to the present invention includes a control device that performs collision avoidance control to avoid a collision between the vehicle and an object in front of it when there is a possibility that the vehicle will collide with the object in front of it. The collision avoidance control includes: a bilateral braking and steering avoidance control that avoids a collision between the vehicle and the object by applying equal or substantially equal braking force to the wheels on both sides of the vehicle to forcibly decelerate the vehicle and forcibly turning the vehicle so that it travels around the object; a first unilateral braking and steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the right wheel of the vehicle than to the left wheel to forcibly decelerate the vehicle and forcibly turning the vehicle so that it travels around the object; a second unilateral braking and steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the left wheel of the vehicle than to the right wheel to forcibly decelerate the vehicle and forcibly turning the vehicle so that it travels around the object; and a braking avoidance control that avoids a collision between the vehicle and the object by forcibly decelerating and stopping the vehicle without forcibly turning the vehicle.

[0008] Furthermore, in the driving assistance device according to the present invention, when there is a possibility that the vehicle may collide with the object, the control device executes the braking avoidance control when the deceleration of the vehicle is less than or equal to a predetermined deceleration when the braking avoidance control is executed, and when there is a possibility that the vehicle may collide with the object, and the deceleration of the vehicle is greater than the predetermined deceleration when the braking avoidance control is executed, and the condition for increasing the amount of turning, which is the amount of turning of the vehicle with respect to the change in the steering angle of the vehicle when the vehicle is forcibly turned by the collision avoidance control, is not met, the control device executes the bilateral braking steering avoidance control, and when there is a possibility that the vehicle may collide with the object When the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, the turning amount increase requirement is met, and the collision avoidance control forces the vehicle to turn to the right to avoid the object, the first one-sided braking steering avoidance control is executed. When there is a possibility that the vehicle will collide with the object, when the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, the turning amount increase requirement is met, and the collision avoidance control forces the vehicle to turn to the left to avoid the object, the second one-sided braking steering avoidance control is executed.

[0009] Furthermore, in the driving assistance device according to the present invention, the condition for increasing the turning amount is a condition that is met, for example, when the bilateral braking and steering avoidance control is unable to drive the vehicle in a manner that avoids the object.

[0010] Furthermore, in the driving support device according to the present invention, the condition for requiring an increase in the turning amount is, for example, a condition that is met when the turning rate required to drive the vehicle in a manner that avoids the object is greater than a predetermined turning rate.

[0011] Furthermore, in the driving support device according to the present invention, the predetermined turning rate is, for example, the maximum value of the turning rate that can be achieved by the bilateral braking steering avoidance control.

[0012] Furthermore, in the driving support device according to the present invention, the condition for increasing the turning amount is, for example, a condition that is met when the amount of turning of the vehicle that can be achieved by the bilateral braking and steering avoidance control is smaller than the amount of turning of the vehicle required to drive the vehicle in a manner that avoids the object.

[0013] Furthermore, in the driving assistance device according to the present invention, the control device may be configured not to execute the two-sided braking and steering avoidance control, the first one-sided braking and steering avoidance control, and the second one-sided braking and steering avoidance control if there is a possibility that the vehicle will collide with an object other than the object when the two-sided braking and steering avoidance control, the first one-sided braking and steering avoidance control, or the second one-sided braking and steering avoidance control is executed.

[0014] Furthermore, in the driver assistance device according to the present invention, the vehicle is equipped with, for example, a braking device that brakes the vehicle. In this case, the predetermined deceleration is, for example, the maximum value of the deceleration of the vehicle that can be achieved by the braking device.

[0015] Furthermore, the driving assistance method according to the present invention is a method for performing collision avoidance control to avoid a collision between the vehicle and an object in front of it when there is a possibility that the vehicle will collide with the object in front of it. The collision avoidance control includes: a bilateral braking steering avoidance control that avoids a collision between the vehicle and the object by applying equal or substantially equal braking force to the wheels on both sides of the vehicle to forcibly decelerate the vehicle and forcibly turning the vehicle so that it travels around the object; a first unilateral braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the right wheel of the vehicle than to the left wheel to forcibly decelerate the vehicle and forcibly turning the vehicle so that it travels around the object; a second unilateral braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the left wheel of the vehicle than to the right wheel to forcibly decelerate the vehicle and forcibly turning the vehicle so that it travels around the object; and a braking avoidance control that avoids a collision between the vehicle and the object by forcibly decelerating and stopping the vehicle without forcibly turning the vehicle.

[0016] Furthermore, the driving assistance method according to the present invention includes the steps of: executing the braking avoidance control when there is a possibility that the vehicle may collide with the object and the deceleration of the vehicle when the braking avoidance control is executed is less than or equal to a predetermined deceleration; executing the bilateral braking steering avoidance control when there is a possibility that the vehicle may collide with the object and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the turning amount increase requirement condition, which is the amount of turning of the vehicle with respect to the change in steering angle of the vehicle when the vehicle is forcibly turned by the collision avoidance control, is not met; and when there is a possibility that the vehicle may collide with the object In cases where the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, the turning amount increase requirement is met, and the collision avoidance control forces the vehicle to turn to the right to avoid the object, the system includes the step of executing the first one-sided braking steering avoidance control. In cases where there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, the turning amount increase requirement is met, and the collision avoidance control forces the vehicle to turn to the left to avoid the object, the system includes the step of executing the second one-sided braking steering avoidance control.

[0017] Furthermore, the driving assistance program according to the present invention is a program that performs collision avoidance control to avoid a collision between the vehicle and an object in front of it when there is a possibility that the vehicle will collide with the object in front of it. The collision avoidance control includes: a bilateral braking steering avoidance control that avoids a collision between the vehicle and the object by applying equal or substantially equal braking force to the wheels on both sides of the vehicle to forcibly decelerate the vehicle and forcibly turning the vehicle so that it travels around the object; a first unilateral braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the right wheel of the vehicle than to the left wheel to forcibly decelerate the vehicle and forcibly turning the vehicle so that it travels around the object; a second unilateral braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the left wheel of the vehicle than to the right wheel to forcibly decelerate the vehicle and forcibly turning the vehicle so that it travels around the object; and a braking avoidance control that avoids a collision between the vehicle and the object by forcibly decelerating and stopping the vehicle without forcibly turning the vehicle.

[0018] Furthermore, the driving assistance program according to the present invention executes the braking avoidance control when there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is less than or equal to a predetermined deceleration. When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the amount of turning, which is the amount of turning of the vehicle with respect to the change in the steering angle of the vehicle when the vehicle is forcibly turned by the collision avoidance control, is not met, the program executes the bilateral braking steering avoidance control. In the event that the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, the turning amount increase requirement is met, and the collision avoidance control forces the vehicle to turn to the right to avoid the object, the first one-sided braking steering avoidance control is executed. In the event that there is a possibility of the vehicle colliding with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, the turning amount increase requirement is met, and the collision avoidance control forces the vehicle to turn to the left to avoid the object, the second one-sided braking steering avoidance control is executed.

[0019] According to the present invention, by forcibly decelerating the vehicle while turning, a collision between the vehicle and an object in front can be more reliably avoided.

[0020] The components of the present invention are not limited to the embodiments described below with reference to the drawings. Other objects, features, and incidental advantages of the present invention will be readily apparent from the description of the embodiments. [Brief explanation of the drawing]

[0021] [Figure 1] Figure 1 shows a driver assistance device and a vehicle (the vehicle itself) equipped with it according to an embodiment of the present invention. [Figure 2] Figure 2 is a diagram showing the distance and the like between the host vehicle and an object (vehicle) in front of it. [Figure 3] (A) of FIG. 3 is a diagram showing the predicted travel region of the host vehicle, and (B) of FIG. 3 is a diagram showing a scene where an object (vehicle) exists in the predicted travel region of the host vehicle. [Figure 4] Figure 4 is a diagram showing a scene where the host vehicle approaches an object (vehicle) in front of it and the conditions for executing collision avoidance control are satisfied. [Figure 5] Figure 5 is a diagram showing the relationship between the host vehicle speed, the braking avoidance limit time, and the steering avoidance limit time. [Figure 6] (A) of FIG. 6 is a diagram showing a scene where braking force is applied to the host vehicle by braking avoidance control, and (B) of FIG. 6 is a diagram showing a scene where the host vehicle is stopped by braking avoidance control. [Figure 7] Figure 7 is a diagram showing a scene where the host vehicle approaches an object (vehicle) in front of it and the conditions for executing collision avoidance control are satisfied. [Figure 8] (A) of FIG. 8 is a diagram showing the target travel path set by one-sided braking and steering avoidance control, and (B) of FIG. 8 is a diagram showing a scene where the host vehicle starts to turn along the target travel path by one-sided braking and steering avoidance control. [Figure 9] (A) of FIG. 9 is a diagram showing a scene where the host vehicle passes by the side of an object (vehicle) by one-sided braking and steering avoidance control, and (B) of FIG. 9 is a diagram showing a scene where the host vehicle passes by the side of the object (vehicle) and the one-sided braking and steering avoidance control is terminated. [Figure 10] (A) of FIG. 10 is a diagram showing the target travel path set by two-sided braking and steering avoidance control, and (B) of FIG. 10 is a diagram showing a scene where the host vehicle starts to turn along the target travel path by two-sided braking and steering avoidance control. [Figure 11] (A) of FIG. 11 is a diagram showing a scene where the host vehicle passes by the side of an object (vehicle) by two-sided braking and steering avoidance control, and (B) of FIG. 11 is a diagram showing a scene where the host vehicle passes by the side of the object (vehicle) and the two-sided braking and steering avoidance control is terminated. [Figure 12]Figure 12(A) shows a scenario where a following vehicle (a vehicle traveling behind the vehicle) is present when the collision avoidance control execution conditions are met, and Figure 12(B) shows a scenario where the collision avoidance control execution conditions are met for an object (person) that is about to cross the vehicle's lane. [Figure 13] Figure 13(A) shows the target driving path set by non-braking steering avoidance control, and Figure 13(B) shows the moment when the vehicle begins to turn along the target driving path by non-braking steering avoidance control. [Figure 14] Figure 14(A) shows a scene in which the vehicle is passing alongside an object (vehicle) due to non-braking steering avoidance control, and Figure 14(B) shows a scene in which the vehicle has passed alongside the object (vehicle) and the non-braking steering avoidance control has ended. [Figure 15] Figure 15 illustrates a scenario where another object (a person) is present in the space to the side of the object (a vehicle) in front of the vehicle that is to be avoided. [Figure 16] Figure 16 is a flowchart showing the routine executed by the driver assistance device according to an embodiment of the present invention. [Modes for carrying out the invention]

[0022] Hereinafter, a driver assistance device according to an embodiment of the present invention will be described with reference to the drawings. As shown in Figure 1, the driver assistance device 10 according to an embodiment of the present invention is mounted on a vehicle (the vehicle 100).

[0023] <ecu> The driver assistance system 10 is equipped with an ECU 90 as a control unit. ECU is an abbreviation for Electronic Control Unit. The ECU 90 mainly consists of a microcomputer. The microcomputer includes a CPU, ROM, RAM, non-volatile memory, and interfaces. The CPU is designed to realize various functions by executing instructions, programs, or routines stored in the ROM.

[0024] <Traction device> Furthermore, the vehicle 100 is equipped with a running gear 20. The running gear 20 includes a drive unit 21, a braking unit 22, and a steering unit 23.

[0025] <Drive system> The drive unit 21 is a device that outputs drive torque (driving force) to be applied to the vehicle 100 in order to move the vehicle 100, and is, for example, an internal combustion engine or a motor. The drive unit 21 is electrically connected to the ECU 90. The ECU 90 can control the drive torque output from the drive unit 21 by controlling the operation of the drive unit 21.

[0026] <Brake device> The braking device 22 is a device that outputs braking torque (braking force) applied to the vehicle 100 in order to brake the 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, that is, the braking torque applied to each wheel of the 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 allow individual control of the braking torque applied to each wheel of the vehicle 100.

[0027] <Steering gear> The steering device 23 is a device that outputs steering torque (steering force) applied to the vehicle 100 in order to steer the 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, that is, the steering torque applied to the vehicle 100 by the steering device 23, by controlling the operation of the steering device 23.

[0028] <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.

[0029] <Accelerator pedal operation volume> 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 the detected information of the amount of operation of the accelerator pedal 31 to the ECU 90. Based on this information, the ECU 90 acquires the amount of operation of the accelerator pedal 31 as the accelerator pedal operation amount AP.

[0030] The ECU 90 calculates and obtains the required driving force (required driving torque) based on the accelerator pedal operation amount AP and the vehicle's speed 100. The required driving force is the driving force that the drive unit 21 is required to output. Except when performing brake avoidance control, one-sided brake steering avoidance control, and two-sided brake steering avoidance control described later, the ECU 90 controls the operation of the drive unit 21 so that the required driving force is output.

[0031] <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 the detected information of the brake pedal operation amount 33 to the ECU 90. Based on this information, the ECU 90 acquires the brake pedal operation amount 33 as brake pedal operation amount BP.

[0032] The ECU90 calculates and obtains the required braking force (required braking torque) based on the brake pedal operation amount BP. The required braking force is the braking force that the braking device 22 is required to output. Except when performing brake avoidance control, one-sided brake steering avoidance control, and two-sided brake steering avoidance control described later, the ECU90 controls the operation of the braking device 22 so that the required braking force is output.

[0033] <Steering Angle Sensor> The steering angle sensor 37 is a sensor that detects the rotation angle of the steering shaft 36 relative to the neutral position. The steering angle sensor 37 is electrically connected to the ECU 90. The steering angle sensor 37 transmits the detected rotation angle information of the steering shaft 36 to the ECU 90. Based on this information, the ECU 90 obtains the rotation angle of the steering shaft 36 as the steering angle θ.

[0034] <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 the detected torque information to the ECU 90. Based on this information, the ECU 90 obtains the torque input by the driver to the steering shaft 36 via the steering wheel 35 (driver input torque).

[0035] <Vehicle motion detection device> The vehicle momentum detection device 50 is a device that detects the momentum of the vehicle 100, and in this example, it includes a vehicle speed detection device 51, a longitudinal acceleration sensor 52, a lateral acceleration sensor 53, and a yaw rate sensor 54.

[0036] <Vehicle speed detection device> The vehicle speed detection device 51 is a device that detects the driving speed of the 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 the detected vehicle speed information of the vehicle 100 to the ECU 90. Based on this information, the ECU 90 obtains the driving speed of the vehicle 100 (vehicle speed V100).

[0037] The ECU90 calculates and obtains the required steering force (required steering torque) based on the acquired steering angle θ, driver input torque, and vehicle speed V100. The required steering force is the steering force that the steering device 23 is required to output. Except when performing side braking steering avoidance control and bidirectional braking steering avoidance control described later, the ECU90 controls the operation of the steering device 23 so that the required steering force is output from the steering device 23.

[0038] <Vertical Acceleration Sensor> The longitudinal acceleration sensor 52 is a sensor that detects the longitudinal acceleration of the vehicle 100. The longitudinal acceleration sensor 52 is electrically connected to the ECU 90. The longitudinal acceleration sensor 52 transmits the detected acceleration information to the ECU 90. Based on this information, the ECU 90 obtains the longitudinal acceleration of the vehicle 100 as the longitudinal acceleration Gx.

[0039] <Lateral acceleration sensor> The lateral acceleration sensor 53 is a sensor that detects the lateral (widthwise) acceleration of the vehicle 100. The lateral acceleration sensor 53 is electrically connected to the ECU 90. The lateral acceleration sensor 53 transmits the detected acceleration information to the ECU 90. Based on this information, the ECU 90 obtains the lateral acceleration of the vehicle 100 as the lateral acceleration Gy.

[0040] <Yaw rate sensor> The yaw rate sensor 54 is a sensor that detects the yaw rate YR of the vehicle 100. The yaw rate sensor 54 is electrically connected to the ECU 90. The yaw rate sensor 54 transmits the detected yaw rate YR information to the ECU 90. The ECU 90 obtains the yaw rate YR of the vehicle 100 based on that information.

[0041] Alternatively, instead of the vertical acceleration sensor 52, the horizontal acceleration sensor 53, and the yaw rate sensor 54, an IMU (Inertial Measurement Unit) that integrates these three sensors into a single unit may be used.

[0042] <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, it is equipped with a radio wave sensor 61 and an image sensor 62. The radio wave sensor 61 is, for example, a radar sensor (millimeter-wave radar, etc.). The image sensor 62 is, for example, a camera. The surrounding information detection device 60 may also be equipped with an ultrasonic sensor (clearance sonar) or other sound wave sensor, or an optical sensor (LiDAR) or a ToF sensor (Time of Flight sensor).

[0043] <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) related to the transmitted 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) related to the detected objects to the ECU 90. Based on this information (radio wave information), the ECU 90 can obtain information (surrounding detection information ID) related to objects present in the vicinity of the vehicle 100.

[0044] In this example, the objects include vehicles, motorcycles, bicycles, and people.

[0045] <Image Sensor> The image sensor 62 is also electrically connected to the ECU 90. The image sensor 62 captures images of the area around the vehicle 100 and transmits information related to the captured images to the ECU 90. Based on this information (image information), the ECU 90 can obtain information about the area around the vehicle 100 (surrounding detection information ID).

[0046] As shown in Figure 2, the ECU 90 detects an object (forward object 200) in front of the vehicle 100 based on the surrounding detection information ID. The forward object 200 can be a vehicle, motorcycle, bicycle, or person, and in the example shown in Figure 2, it is a vehicle.

[0047] When the ECU 90 detects an object 200 in front, it can, for example, obtain information such as "the distance between the object 200 and the vehicle 100 (object distance D200)" and "the speed of the vehicle 100 relative to the object 200 (relative speed ΔV200)" based on the surrounding detection information ID.

[0048] Furthermore, based on the surrounding detection information ID, the ECU 90 recognizes the left lane marking LM_L and the right lane marking LM_R that define the driving lane of the vehicle 100 (the vehicle's lane LN1). Based on the recognized left and right lane markings LM (i.e., the left lane marking LM_L and the right lane marking LM_R), the ECU 90 can determine the range of the vehicle's lane LN1. In Figure 2, the symbol LN2 indicates the oncoming lane for the vehicle's lane LN1.

[0049] <Overview of the operation of the driver assistance system> Next, we will explain the overview of the operation of the driver assistance device 10.

[0050] <Normal driving control> The driver assistance system 10 performs processing to detect objects such as vehicles in front of the vehicle 100 in the direction of travel, based on surrounding detection information IDs, while the vehicle 100 is in motion. When the driver assistance system 10 does not detect any objects in front of the vehicle 100 in the direction of travel, it performs normal driving control.

[0051] Normal driving control is a control that controls the operation of the drive unit 21 so that the required driving force is output from the drive unit 21 when the required driving force is greater than zero, controls the operation of the brake unit 22 so that the required braking force is output from the brake unit 22 when the required braking force is greater than zero, and controls the operation of the steering unit 23 so that the required steering force is output from the steering unit 23 when the required steering force is greater than zero.

[0052] When the driver assistance device 10 detects an object in front of the vehicle 100 in the direction of travel, it determines whether or not the object (forward object 200) is within the predicted driving area A100. This determination is made based on the surrounding detection information ID.

[0053] The predicted driving region A100, as shown in Figure 3(A), is a region centered on the predicted driving path R100 of the vehicle 100 and having a width equal to the width of the vehicle 100. The predicted driving path R100 is the driving path that the vehicle 100 is predicted to travel if it maintains its current steering angle θ. Therefore, although the predicted driving path R100 shown in Figure 3(A) is a straight line, it may also be a curve depending on the circumstances.

[0054] If the detected forward object 200 is not within the predicted driving area A100, the driver assistance device 10 continues normal driving control.

[0055] Meanwhile, as shown in Figure 3(B), when the driver assistance device 10 determines that the detected object 200 ahead is within the predicted driving area A100, it obtains the predicted time to arrive TTC. The predicted time to arrive TTC is the time that is predicted to take for the vehicle 100 to reach the object 200 ahead. The driver assistance device 10 obtains the predicted time to arrive TTC by dividing the object distance D200 by the relative velocity ΔV200 (TTC = D200 / ΔV200). While the driver assistance device 10 determines that the object 200 ahead is within the predicted driving area A100, it obtains the object distance D200, relative velocity ΔV200, and predicted time to arrive TTC at predetermined calculation cycles.

[0056] The predicted time to arrival (TTC) decreases as the vehicle 100 approaches the object 200 ahead, assuming a constant relative velocity ΔV200. Therefore, the predicted time to arrival (TTC) is an indicator of the probability that the vehicle 100 will not collide with the object 200 ahead, and this indicator decreases as the predicted time to arrival (TTC) decreases and the probability of the vehicle 100 not colliding with the object 200 ahead decreases.

[0057] The driver assistance device 10 determines whether the predicted arrival time TTC has shortened to a predetermined time (collision detection time TTCth). The driver assistance device 10 continues normal driving control as long as the predicted arrival time TTC is longer than the collision detection time TTCth.

[0058] As shown in Figure 4, if the driver of the vehicle 100 does not perform collision avoidance steering maneuvers (operations made to the steering wheel 35 to avoid a collision between the vehicle 100 and the object 200 in front), and the vehicle 100 approaches the object 200 in front, and the predicted arrival time TTC shortens to the collision determination time TTCth, the driver assistance device 10 determines that if the vehicle 100 continues to drive, there is a possibility that the vehicle 100 will collide with the object 200 in front. If the driver assistance device 10 determines that there is a possibility that the vehicle 100 will collide with the object 200 in front, it determines that the collision avoidance control execution conditions have been met.

[0059] <Collision Avoidance Control> When the driver assistance device 10 determines that the conditions for executing collision avoidance control have been met, it executes collision avoidance control to avoid a collision between the vehicle 100 and the object 200 in front. In this example, the collision avoidance control includes two types of control: braking avoidance control and steering avoidance control. When the driver assistance device 10 determines that the conditions for executing collision avoidance control have been met, it executes either the braking avoidance control or the steering avoidance control to avoid a collision between the vehicle 100 and the object 200 in front.

[0060] In this example, braking avoidance control is a control that forcibly decelerates the vehicle 100 and stops it before the object 200 in front. On the other hand, steering avoidance control is a control that forcibly turns the vehicle 100 so that it drives to avoid the object 200 in front. More specifically, it is a control that forcibly turns the vehicle 100 so that it passes alongside the object 200 in front, and forcibly decelerates the vehicle 100 if necessary.

[0061] The driver assistance device 10 performs braking avoidance control if the steering avoidance requirement is not met, and performs steering avoidance control if the steering avoidance requirement is met.

[0062] The steering avoidance requirement is set, for example, to the condition that the deceleration of the vehicle 100 when braking avoidance control is performed is greater than a predetermined deceleration. In this case, the predetermined deceleration may be, for example, the maximum deceleration of the vehicle 100 that can be achieved by the braking device 22, or it may be the upper limit of the deceleration of the vehicle 100 that can ensure the safety of the occupants of the vehicle 100, including the driver.

[0063] Alternatively, the steering avoidance requirement is set to, for example, that the braking force applied to the vehicle 100 when brake avoidance control is performed is greater than a predetermined braking force. In this case, the predetermined braking force may be, for example, the maximum braking force that can be applied to the vehicle 100 by the braking device 22, or it may be the upper limit of braking force that can ensure the safety of the occupants of the vehicle 100, including the driver, when applied to the vehicle 100.

[0064] However, in this example, the steering avoidance requirement is set to the following conditions.

[0065] The minimum predicted arrival time TTC (braking avoidance limit time TTC_B) at which a collision between the vehicle 100 and the object 200 ahead can be avoided by braking avoidance control increases as the vehicle speed V100 increases, as shown by line TTB in Figure 5. Similarly, the minimum predicted arrival time TTC (steering avoidance limit time TTC_S) at which a collision between the vehicle 100 and the object 200 ahead can be avoided by steering avoidance control without deceleration of the vehicle 100 decreases as the vehicle speed V100 increases, as shown by line TTS in Figure 5. Furthermore, line TTB (the line showing the relationship between braking avoidance limit time TTC_B and vehicle speed V100) and line TTS (the line showing the relationship between steering avoidance limit time TTC_S and vehicle speed V100) intersect at a certain vehicle speed Vth. Therefore, the relative magnitudes of braking avoidance limit time TTC_B and steering avoidance limit time TTC_S are reversed at a certain vehicle speed Vth. Specifically, when the vehicle speed V100 is less than a certain vehicle speed Vth, the braking avoidance limit time TTC_B is smaller than the steering avoidance limit time TTC_S, and when the vehicle speed V100 is greater than a certain vehicle speed Vth, the steering avoidance limit time TTC_S is smaller than the braking avoidance limit time TTC_B.

[0066] This means that when the vehicle speed V100 is relatively small, avoiding a collision between the vehicle 100 and the object 200 ahead using braking avoidance control allows for a later start to collision avoidance control than avoiding a collision between the vehicle 100 and the object 200 ahead using steering avoidance control. On the other hand, when the vehicle speed V100 is relatively large, avoiding a collision between the vehicle 100 and the object 200 ahead using steering avoidance control allows for a later start to collision avoidance control than avoiding a collision between the vehicle 100 and the object 200 ahead using braking avoidance control.

[0067] In this situation, some drivers may feel that the timing of the activation of brake avoidance control or steering avoidance control is too early. Therefore, it is preferable to activate brake avoidance control or steering avoidance control as late as possible.

[0068] Based on the above, the driver assistance 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, depending on the vehicle speed V100. Specifically, when the vehicle speed V100 is less than a certain vehicle speed Vth (predetermined vehicle speed Vth), the driver assistance device 10 sets the braking avoidance limit time TTC_B as the collision determination time TTCth, and when the vehicle speed V100 is greater than the predetermined vehicle speed Vth, it sets the steering avoidance limit time TTC_S as the collision determination time TTCth. Furthermore, when the 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 driver assistance device 10 is configured to set the braking avoidance limit time TTC_B as the collision determination time TTCth.

[0069] The driver assistance device 10 then determines that the steering avoidance requirement is met if the vehicle speed V100 at that time is greater than the predetermined vehicle speed Vth, or if the steering avoidance limit time TTC_S corresponding to the vehicle speed V100 at that time is less than the braking avoidance limit time TTC_B corresponding to the vehicle speed V100 at that time.

[0070] In other words, in this example, the steering avoidance requirement is that the vehicle speed V100 at that time is greater than the predetermined vehicle speed Vth, or that the steering avoidance limit time TTC_S corresponding to the vehicle speed V100 at that time is less than the braking avoidance limit time TTC_B corresponding to the vehicle speed V100 at that time.

[0071] <Brake Avoidance Control> If the steering avoidance requirement is not met, the driver assistance device 10 initiates brake avoidance control and forcibly applies braking force to the vehicle 100, as shown in Figure 6(A). As a result, the vehicle 100 stops in front of the object 200, as shown in Figure 6(B).

[0072] According to this, a collision between the vehicle 100 and the object 200 in front can be avoided.

[0073] On the other hand, if the steering avoidance requirement is met, the driving support device 10 determines whether or not the turning amount increase requirement is met.

[0074] <Requirements for increased turning radius> For example, as shown in Figure 7, when the collision avoidance control execution conditions are met, there is space to the right of the object 200 in front for the vehicle 100 to travel. Therefore, when attempting to avoid a collision between the vehicle 100 and the object 200 by having the vehicle 100 pass through the space to the right of the object 200 in front, if the object 200 in front begins to move to the right, it may be impossible to avoid a collision between the vehicle 100 and the object 200 in front unless the vehicle 100 makes a large right turn.

[0075] In such cases, it is preferable to increase the amount of turning of the vehicle 100 (turning rate of the vehicle 100) relative to the amount of change in the steering angle of the vehicle 100 when the vehicle 100 is forcibly turned by collision avoidance control.

[0076] In this example, the condition for increasing the turning amount is that there is a demand to increase the amount of turning of the vehicle 100 (turning rate of the vehicle 100) in relation to the change in the steering angle of the vehicle 100 when the vehicle 100 is forcibly turned by collision avoidance control, and in particular, the condition is that the vehicle 100 cannot be driven to avoid the object 200 in front in the bilateral braking steering avoidance control described later.

[0077] In this example, the condition for increasing the turning amount is set to the condition that the turning rate of the vehicle 100 required to drive the vehicle 100 to avoid the object 200 in front is greater than a predetermined turning rate. In this example, the predetermined turning rate is set to the maximum value of the turning rate of the vehicle 100 that can be achieved by the bilateral braking steering avoidance control described later.

[0078] Furthermore, the condition for increasing the turning amount may be set as follows: the turning amount of the vehicle 100 that can be achieved by the bilateral braking and steering avoidance control described later is smaller than the turning amount of the vehicle 100 required to drive the vehicle 100 in a way that avoids the object 200 in front; the relative speed ΔV200 between the vehicle 100 and the object 200 in front is greater than a predetermined speed; or the overlap ratio between the vehicle 100 and the object 200 in front is greater than a predetermined value. The overlap ratio between the vehicle 100 and the object 200 in front is a value that indicates the ratio of the width of the vehicle 100 to the width of the object 200 in front of the vehicle 100.

[0079] Alternatively, the condition for increasing the turning amount may be set to the condition that when collision avoidance control attempts to make the vehicle 100 turn right so that it passes to the right of the object 200 in front, the object 200 in front begins to move to the right, or when collision avoidance control attempts to make the vehicle 100 turn left so that it passes to the left of the object 200 in front, the object 200 in front begins to move to the left. The determination of whether the object 200 in front has started to move to the right, and whether the object 200 in front has moved to the left, is made based on the surrounding detection information ID.

[0080] <Steering avoidance control> In this example, steering avoidance control includes two types of control: bilateral braking steering avoidance control and unilateral braking steering avoidance control.

[0081] <Dual-sided steering avoidance control> Bilateral braking and steering avoidance control is a control method that applies equal or approximately equal braking force (the difference is within a range smaller than a predetermined value) to the wheels on both sides of the vehicle 100 to forcibly decelerate the vehicle 100, while simultaneously forcibly turning the vehicle 100 so that it can avoid the object 200 in front of it.

[0082] In particular, in this example, the bilateral braking and steering avoidance control is a control that applies equal braking force to both the left and right wheels of the vehicle 100 to forcibly decelerate the vehicle 100, while simultaneously applying steering force to the vehicle 100 to forcibly turn the vehicle 100 so that it avoids the object 200 in front of it. In particular, the bilateral braking and steering avoidance control is a control that applies equal braking force to both the left and right wheels of the vehicle 100 to forcibly decelerate the vehicle 100, while simultaneously applying steering force to the vehicle 100 to forcibly turn the vehicle 100 so that it passes alongside the object 200 in front of it.

[0083] <One-sided braking and steering avoidance control> On the other hand, one-sided braking steering avoidance control is a control method that applies a greater braking force to the wheels of the vehicle 100 on the side that forces the vehicle 100 to turn than to the wheels on the opposite side, thereby forcibly decelerating the vehicle 100 and forcibly turning the vehicle 100 so that it can avoid the object 200 in front of it. In other words, the one-sided braking steering avoidance control is a control that, when forcing the vehicle 100 to turn right to avoid the object 200 in front, applies a greater braking force (or a braking force greater than or equal to a predetermined value) to the right wheel of the vehicle 100 than to the left wheel, forcing the vehicle 100 to decelerate while forcing the vehicle 100 to turn so that it avoids the object 200 in front. When forcing the vehicle 100 to turn left to avoid the object 200 in front, applies a greater braking force (or a braking force greater than or equal to a predetermined value) to the left wheel of the vehicle 100 than to the right wheel, forcing the vehicle 100 to decelerate while forcing the vehicle 100 to turn so that it avoids the object 200 in front.

[0084] In particular, in this example, the one-sided braking steering avoidance control is a control method that applies braking force to only one of the left or right wheels of the vehicle 100 to forcibly decelerate the vehicle 100, while simultaneously applying steering force to the vehicle 100 to forcibly turn the vehicle 100 so that it passes alongside the object 200 in front of it. In other words, the one-sided braking steering avoidance control is a control system that, when forcing the vehicle 100 to turn right to avoid the object 200 in front, applies braking force only to the right wheel of the vehicle 100 to forcibly decelerate the vehicle 100 while forcibly turning the vehicle 100 to avoid the object 200 in front, and when forcing the vehicle 100 to turn left to avoid the object 200 in front, applies braking force only to the left wheel of the vehicle 100 to forcibly decelerate the vehicle 100 while forcibly turning the vehicle 100 to avoid the object 200 in front.

[0085] Therefore, when the driver assistance device 10 uses one-sided braking and steering avoidance control to forcibly turn the vehicle 100 so that it passes to the right of the object 200 in front, it applies braking force only to the right wheel of the vehicle 100, without applying braking force to the left wheel, while forcibly turning the vehicle 100. As a result, when the one-sided braking and steering avoidance control is started and the vehicle 100 is forcibly turned to the right, braking force is applied only to the right wheel of the vehicle 100, so the vehicle 100 can be turned sharply to the right.

[0086] On the other hand, when the driver assistance device 10 uses one-sided braking and steering avoidance control to forcibly turn the vehicle 100 so that it passes to the left of the object 200 in front, it applies braking force only to the left wheel of the vehicle 100, without applying braking force to the right wheel, while forcibly turning the vehicle 100. As a result, when the one-sided braking and steering avoidance control is started and the vehicle 100 is forcibly turned to the left, braking force is applied only to the left wheel of the vehicle 100, so the vehicle 100 can be turned sharply to the left.

[0087] <Execution of one-sided braking and steering avoidance control> When the driving assistance device 10 is met, it performs one-sided braking steering avoidance control. When the driving assistance device 10 starts one-sided braking steering avoidance control, as shown in Figure 8(A), if there is space to drive the vehicle 100 to the right of the object 200 in front, it sets a path that passes to the right of the object 200 as the path for the vehicle 100 to travel (target driving path Rtgt). On the other hand, if there is space to drive the vehicle 100 to the left of the object 200 in front, the driving assistance device 10 sets a path that passes to the left of the object 200 as the path for the vehicle 100 to travel (target driving path Rtgt).

[0088] Then, as shown in Figure 8(B), the driving support device 10 applies braking force to only one side of the vehicle 100's wheels while simultaneously applying steering force to the vehicle 100 so that it travels along the target driving path Rtgt.

[0089] As a result, as shown in Figure 9(A), the vehicle 100 passes alongside the object 200 in front, and as shown in Figure 9(B), the vehicle 100 passes alongside the object 200 in front. This avoids a collision between the vehicle 100 and the object 200 in front. When the vehicle 100 passes alongside the object 200 in front, the driver assistance device 10 terminates the one-sided braking and steering avoidance control.

[0090] According to this, even in situations where the requirement for increased turning is met, a collision between the vehicle 100 and the object 200 in front can be avoided.

[0091] Furthermore, when the driver assistance device 10 performs one-sided braking and steering avoidance control so that the vehicle 100 passes to the right of the object 200 in front, it is configured not to apply braking force to the vehicle 100 after forcibly turning the vehicle 100 to the right and then turning it to the left (when the steering angle is reversed). However, for example, it may be configured to apply braking force only to the left wheel of the vehicle 100 when turning it to the left. Similarly, when the driver assistance device 10 performs one-sided braking and steering avoidance control so that the vehicle 100 passes to the left of the object 200 in front, it is configured not to apply braking force to the vehicle 100 after forcibly turning the vehicle 100 to the left and then turning it to the right (when the steering angle is reversed). However, for example, it may be configured to apply braking force only to the right wheel of the vehicle 100 when turning it to the right.

[0092] <Execution of bidirectional braking and steering avoidance control> On the other hand, if the condition for increasing the turning amount is not met, the driver assistance device 10 performs bilateral braking and steering avoidance control. When the driver assistance device 10 starts bilateral braking and steering avoidance control, as shown in Figure 10(A), if there is space to drive the vehicle 100 to the right of the object 200 in front, it sets a path that passes to the right of the object 200 as the path for the vehicle 100 to travel (target driving path Rtgt). On the other hand, if there is space to drive the vehicle 100 to the left of the object 200 in front, the driver assistance device 10 sets a path that passes to the left of the object 200 as the path for the vehicle 100 to travel (target driving path Rtgt).

[0093] Then, as shown in Figure 10(B), the driving support device 10 applies braking force to the wheels on both sides of the vehicle 100, while simultaneously applying steering force to the vehicle 100 so that it travels along the target driving path Rtgt.

[0094] As a result, as shown in Figure 11(A), the vehicle 100 passes alongside the object 200 in front, and as shown in Figure 11(B), the vehicle 100 passes alongside the object 200 in front. This avoids a collision between the vehicle 100 and the object 200 in front. When the vehicle 100 passes alongside the object 200 in front, the driver assistance device 10 terminates the bilateral braking and steering avoidance control. When bilateral braking and steering avoidance control is performed, the vehicle 100 stops when it reaches the space beside the object 200 in front.

[0095] This makes it possible to avoid a collision between the vehicle 100 and the object 200 in front.

[0096] <Non-braking steering avoidance control> Furthermore, as shown in Figure 12(A), if there is a vehicle (following vehicle 300) traveling behind vehicle 100, and the distance between the following vehicle 300 and vehicle 100 is shorter than a predetermined distance, executing steering avoidance control that involves deceleration of vehicle 100, such as one-sided braking steering avoidance control or two-sided braking steering avoidance control, could cause the following vehicle 300 to rear-end vehicle 100.

[0097] Furthermore, as shown in Figure 12(B), if the object 200 ahead is an object such as a person moving laterally relative to the vehicle's lane LN1, executing steering avoidance control that involves deceleration of the vehicle 100, such as one-sided braking steering avoidance control or two-sided braking steering avoidance control, could result in the vehicle 100 colliding with the object 200 ahead, depending on the object's speed.

[0098] Therefore, the driver assistance device 10 may be configured to perform non-braking steering avoidance control when the steering avoidance requirement condition is met and the braking prohibition condition is also met.

[0099] Non-braking steering avoidance control is a control method that forces the vehicle 100 to turn so that it passes alongside the object 200 in front of it by forcibly applying steering force to the vehicle 100 without applying braking force to the vehicle 100.

[0100] Furthermore, the braking prohibition condition is a condition to prohibit the execution of steering avoidance control (one-sided braking steering avoidance control and two-sided braking steering avoidance control) that involves applying braking force to the vehicle 100. For example, if steering avoidance control (one-sided braking steering avoidance control and two-sided braking steering avoidance control) that involves applying braking force to the vehicle 100 is executed, there is a possibility that the following vehicle 300 will rear-end the vehicle 100, and / or if steering avoidance control (one-sided braking steering avoidance control and two-sided braking steering avoidance control) that involves applying braking force to the vehicle 100 is executed, there is a possibility that the vehicle 100 will collide with the object 200 in front, but if the vehicle 100 does not decelerate, the vehicle 100 can be driven to pass alongside the object 200 in front.

[0101] Furthermore, the determination of whether there is a possibility that a following vehicle 300 will rear-end vehicle 100 if steering avoidance control involving the application of braking force to vehicle 100 is performed, and the determination of whether there is a possibility that vehicle 100 will collide with the object 200 ahead if steering avoidance control involving the application of braking force to vehicle 100 is performed, but whether it is possible to drive vehicle 100 so as to pass alongside the object 200 ahead without decelerating vehicle 100, is performed based on the surrounding detection information ID.

[0102] When the driver assistance device 10 starts non-braking steering avoidance control, as shown in Figure 13(A), if there is space to drive the vehicle 100 to the right of the object 200 in front, it sets a path that passes to the right of the object 200 as the path for the vehicle 100 to travel (target driving path Rtgt). On the other hand, if there is space to drive the vehicle 100 to the left of the object 200 in front, the driver assistance device 10 sets a path that passes to the left of the object 200 as the path for the vehicle 100 to travel (target driving path Rtgt).

[0103] Then, as shown in Figure 13(B), the driver assistance device 10 begins to apply steering force to the vehicle 100 so that it travels along the target driving path Rtgt. At this time, the driver assistance device 10 does not apply braking force to the vehicle 100.

[0104] As a result, as shown in Figure 14(A), the vehicle 100 passes alongside the object 200 in front, and as shown in Figure 14(B), the vehicle 100 passes alongside the object 200 in front. This avoids a collision between the vehicle 100 and the object 200 in front. When the vehicle 100 passes alongside the object 200 in front, the driver assistance device 10 terminates the non-braking steering avoidance control.

[0105] According to this, even in situations where braking is prohibited, a collision between the vehicle 100 and the object 200 in front can be avoided.

[0106] <Conditions under which steering avoidance is prohibited> Furthermore, as shown in Figure 15, when steering avoidance control (one-sided braking steering avoidance control, two-sided braking steering avoidance control, and non-braking steering avoidance control) is performed 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 path Rtgt is set to pass through the space where the secondary object 400 is located, and the vehicle 100 travels along that target driving path Rtgt, the vehicle 100 will collide with the secondary object 400. In such a case, it is not desirable to perform steering avoidance control.

[0107] Therefore, the driver assistance device 10 may be configured to execute braking avoidance control instead of steering avoidance control when the steering avoidance prohibition condition is met, even if the steering avoidance request condition is met.

[0108] According to this, even in situations where the conditions for prohibiting steering avoidance are met, a collision between the vehicle 100 and the object 200 in front can be avoided.

[0109] <Lane change collision avoidance control> Furthermore, when attempting to avoid a collision between the vehicle 100 and the object 200 ahead using steering avoidance control, there may not be enough space within the vehicle's lane LN1 to allow the vehicle 100 to pass alongside the object 200 ahead. In such cases, when attempting to avoid a collision between the vehicle 100 and the object 200 ahead using steering avoidance control, and there is a parallel lane adjacent to the vehicle's lane LN1, the driver assistance device 10 may be configured to perform lane change collision avoidance control, which involves changing the vehicle 100 into that parallel lane, provided that safety is ensured when changing lanes to that parallel lane (that the vehicle 100 does not come into contact with other vehicles traveling in the parallel lane).

[0110] According to this, even in situations where there is not enough space within the vehicle's lane LN1 to allow the vehicle 100 to pass alongside the object 200 in front when attempting to avoid a collision between the vehicle 100 and the object 200 in front through steering avoidance control, a collision between the vehicle 100 and the object 200 in front can be avoided.

[0111] <Specific operation of driver assistance systems> Next, the specific operation of the driver assistance device 10 will be described. The CPU of the ECU 90 of the driver assistance device 10 according to the embodiment of the present invention is configured to execute the routine shown in Figure 16 at a predetermined calculation cycle. Therefore, at a predetermined timing, the CPU starts processing from step 1600 of the routine shown in Figure 16, proceeds to step 1605, and determines whether or not the collision avoidance control execution conditions are met.

[0112] If the CPU determines "Yes" in step 1605, it proceeds to step 1610 to determine whether the steering avoidance request condition is met. If the CPU determines "Yes" in step 1610, it proceeds to step 1615 to determine whether the braking prohibition condition is met. If the CPU determines "No" in step 1615, it proceeds to step 1620 to determine whether the steering avoidance prohibition condition is met. If the CPU determines "No" in step 1620, it proceeds to step 1625 to determine whether the turning amount increase request condition is met. If the CPU determines "Yes" in step 1625, it proceeds to step 1630 to execute one-sided braking steering avoidance control. Next, the CPU proceeds to step 1655.

[0113] On the other hand, if the CPU determines "No" in step 1635, it proceeds to step 1635 and executes bidirectional braking and steering avoidance control. Next, the CPU proceeds to step 1655.

[0114] Furthermore, if the CPU determines "Yes" in step 1620, it proceeds to step 1650 and executes brake avoidance control. Next, the CPU proceeds to step 1655.

[0115] Furthermore, if the CPU determines "Yes" in step 1615, it proceeds to step 1645 and executes non-braking steering avoidance control. Next, the CPU proceeds to step 1655.

[0116] Furthermore, if the CPU determines "No" in step 1610, it proceeds to step 1640 and executes braking avoidance control. Next, the CPU proceeds to step 1655.

[0117] When the CPU proceeds to step 1655, it determines whether the collision avoidance control has successfully prevented a collision between the vehicle 100 and the object 200 in front of it. If the CPU determines "Yes" in step 1655, it proceeds to step 1660 and locks down the ongoing collision avoidance control. Next, the CPU proceeds to step 1695 and terminates the processing of this routine.

[0118] On the other hand, if the CPU determines "No" at step 1655, it proceeds directly to step 1695 and terminates the processing of this routine.

[0119] Furthermore, if the CPU determines "No" in step 1605, it proceeds directly to step 1695 and terminates the processing of this routine.

[0120] The above describes the specific operation of the driver assistance device 10.

[0121] Furthermore, the present invention is not limited to the embodiments described above, and various modifications can be adopted within the scope of the present invention. [Explanation of symbols]

[0122] 10...Driving assistance system, 20...Running gear, 22...Braking system, 23...Steering system, 60...Surrounding information detection system, 90...ECU, 100...Own vehicle, 200...Vehicle ahead, 300...Following vehicle< / ecu>

Claims

1. The vehicle is equipped with a control device that performs collision avoidance control to avoid a collision between the vehicle and an object in front of it, when there is a possibility of the vehicle colliding with the object in front of it. The collision avoidance control is, A bilateral braking steering avoidance control system that avoids a collision between the vehicle and the object by applying equal or approximately equal braking force to each wheel on both sides of the vehicle to forcibly decelerate the vehicle, and forcibly turning the vehicle so that it moves to avoid the object, A first one-sided braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the right wheel of the vehicle than to the left wheel, thereby forcibly decelerating the vehicle, and forcibly turning the vehicle so that it moves to avoid the object, A second one-sided braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the left wheel of the vehicle than to the right wheel, thereby forcibly decelerating the vehicle, and forcibly turning the vehicle so that it moves to avoid the object, Brake avoidance control that avoids a collision between the vehicle and the object by forcibly decelerating and stopping the vehicle without forcibly turning the vehicle, Includes, In driver assistance systems, The control device is When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is less than or equal to a predetermined deceleration, the braking avoidance control is executed. When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the amount of turning, which is the amount of turning of the vehicle with respect to the change in the steering angle of the vehicle when the vehicle is forcibly turned by the collision avoidance control, is not met, then the bilateral braking steering avoidance control is executed. When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the turning amount is met, and the collision avoidance control forces the vehicle to turn to the right to avoid the object, the first one-sided braking steering avoidance control is executed. When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the turning amount is met, and the collision avoidance control forces the vehicle to turn left to avoid the object, the second one-sided braking steering avoidance control is executed. It is structured in such a way. Driving assistance system.

2. In the driving support device according to claim 1, The aforementioned condition for increasing the turning amount is met when the bilateral braking and steering avoidance control is unable to drive the vehicle in a manner that avoids the object. Driving assistance system.

3. In the driving support device according to claim 1, The aforementioned condition for increasing the turning amount is met when the turning rate required to drive the vehicle to avoid the object is greater than a predetermined turning rate. Driving assistance system.

4. In the driving support device according to claim 3, The predetermined turning rate is the maximum value of the turning rate that can be achieved by the bilateral braking steering avoidance control. Driving assistance system.

5. In the driving support device according to claim 1, The aforementioned condition for increasing the turning amount is met when the amount of turning of the vehicle that can be achieved by the bilateral braking and steering avoidance control is smaller than the amount of turning of the vehicle required to drive the vehicle in a manner that avoids the object. Driving assistance system.

6. In the driving support device according to any one of claims 1 to 5, The control device is configured not to execute the two-sided braking and steering avoidance control, the first one-sided braking and steering avoidance control, or the second one-sided braking and steering avoidance control if there is a possibility that the vehicle will collide with an object other than the object mentioned above when the two-sided braking and steering avoidance control, the first one-sided braking and steering avoidance control, or the second one-sided braking and steering avoidance control is executed. Driving assistance system.

7. In the driving support device according to any one of claims 1 to 6, The aforementioned vehicle is equipped with a braking device for braking the vehicle, The predetermined deceleration is the maximum value of the deceleration of the vehicle that can be achieved by the braking device. Driving assistance system.

8. A driving assistance method that performs collision avoidance control to avoid a collision between the vehicle and an object in front of it when there is a possibility of the vehicle colliding with the object in front of it, The collision avoidance control is, A bilateral braking steering avoidance control system that avoids a collision between the vehicle and the object by applying equal or approximately equal braking force to each wheel on both sides of the vehicle to forcibly decelerate the vehicle, and forcibly turning the vehicle so that it moves to avoid the object, A first one-sided braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the right wheel of the vehicle than to the left wheel, thereby forcibly decelerating the vehicle, and forcibly turning the vehicle so that it moves to avoid the object, A second one-sided braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the left wheel of the vehicle than to the right wheel, thereby forcibly decelerating the vehicle, and forcibly turning the vehicle so that it moves to avoid the object, Brake avoidance control that avoids a collision between the vehicle and the object by forcibly decelerating and stopping the vehicle without forcibly turning the vehicle, Includes, In driver assistance methods, When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is less than or equal to a predetermined deceleration, the steps include: executing the braking avoidance control; When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the amount of turning, which is the amount of turning of the vehicle with respect to the change in the steering angle of the vehicle when the vehicle is forcibly turned by the collision avoidance control, is not met, then the step of executing the bilateral braking steering avoidance control is performed. When there is a possibility that the vehicle may collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the turning amount is met, and the collision avoidance control forces the vehicle to turn to the right to avoid the object, the first step of executing the one-sided braking steering avoidance control is performed. When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the turning amount is met, and the collision avoidance control forces the vehicle to turn left to avoid the object, the second step of executing the one-sided braking steering avoidance control is performed. Having, Driving assistance methods.

9. A driver assistance program that performs collision avoidance control to avoid a collision between the vehicle and an object in front of it when there is a possibility of the vehicle colliding with the object in front of it, The collision avoidance control is, A bilateral braking steering avoidance control system that avoids a collision between the vehicle and the object by applying equal or approximately equal braking force to each wheel on both sides of the vehicle to forcibly decelerate the vehicle, and forcibly turning the vehicle so that it moves to avoid the object, A first one-sided braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the right wheel of the vehicle than to the left wheel, thereby forcibly decelerating the vehicle, and forcibly turning the vehicle so that it moves to avoid the object, A second one-sided braking steering avoidance control that avoids a collision between the vehicle and the object by applying a greater braking force to the left wheel of the vehicle than to the right wheel, thereby forcibly decelerating the vehicle, and forcibly turning the vehicle so that it moves to avoid the object, Brake avoidance control that avoids a collision between the vehicle and the object by forcibly decelerating and stopping the vehicle without forcibly turning the vehicle, Includes, In the driver assistance program, When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is less than or equal to a predetermined deceleration, the braking avoidance control is executed. When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the amount of turning, which is the amount of turning of the vehicle with respect to the change in the steering angle of the vehicle when the vehicle is forcibly turned by the collision avoidance control, is not met, then the bilateral braking steering avoidance control is executed. When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the turning amount is met, and the collision avoidance control forces the vehicle to turn to the right to avoid the object, the first one-sided braking steering avoidance control is executed. When there is a possibility that the vehicle will collide with the object, and the deceleration of the vehicle when the braking avoidance control is executed is greater than the predetermined deceleration, and the condition for increasing the turning amount is met, and the collision avoidance control forces the vehicle to turn left to avoid the object, the second one-sided braking steering avoidance control is executed. It is structured in such a way. Driver assistance program.

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