CN-121973767-A - Front wheel pre-deflection-based rear-end collision prevention and clamping danger avoiding method for vehicle

CN121973767ACN 121973767 ACN121973767 ACN 121973767ACN-121973767-A

Abstract

The invention discloses a rear-end collision prevention and clamping danger avoiding method for a vehicle based on front wheel pre-deflection, which comprises the steps of obtaining running state information and surrounding environment information of the vehicle, judging whether the running state information and the surrounding environment information of the vehicle meet the preset state, namely, the running state information and the low-speed maintenance state, and the front passing blocking condition, judging whether rear-end collision prevention and clamping risks exist when the running state information and the surrounding environment information are met, deciding effective widths of a danger avoiding direction and a safety lateral area on the left side and the right side when the running state information and the low-speed passing blocking condition exist, calculating an optimal deflection guide angle based on collision moment coupling, adjusting the front wheel rotation angle of the vehicle to the optimal deflection guide angle, locking the optimal deflection guide angle, sending multi-mode warning information, and executing correction damping proportion-differential control when the vehicle is detected to be in a starting escape stage. The invention brings the rear vehicle impact moment into the decision closed loop, guides the lateral escape by utilizing the impact energy through actively presetting the front wheel steering angle, avoids the vehicle body from being extruded, and combines yaw stability compensation and warning to ensure the escape stability and safety under extreme working conditions.

Inventors

HUANG GUANFU
LIU YI
CHEN JIAWEI
LIU JINGYI
JING SHENGBO
ZHANG HUAQI

Assignees

榆林智能无人装备创新中心有限公司

Dates

Publication Date: 20260505
Application Date: 20260211

Claims (10)

1. The method for preventing rear-end collision and clamping collision of the vehicle and avoiding danger based on front wheel pre-deflection is characterized by comprising the following steps: Acquiring current running state information and surrounding environment information of a vehicle, wherein the surrounding environment information comprises front obstacle information, rear target vehicle information and side lane space information; judging whether the self vehicle meets a preset state or not based on the running state information and the front obstacle information, wherein the preset state is that the self vehicle is in a static state or a low-speed holding state and a front passing blocking condition exists; Judging whether the self vehicle has a rear-end collision clamping risk or not based on the rear target vehicle information when the preset state is met, and deciding a risk avoiding direction and the effective width of a safety lateral area based on the lateral lane space information on the left side and the right side of the self vehicle when the rear-end collision clamping risk exists; Calculating an optimal deflection guide angle based on impact moment coupling based on the rear target vehicle information, the decided risk avoiding direction and the effective width of the safety lateral area, and adjusting and locking the front wheel steering angle of the vehicle to the optimal deflection guide angle; Sending out multi-mode warning information for front wheel deflection operation executed by the self vehicle; when the own vehicle is detected to be in a start escape phase, a return positive damping proportional-differential control is performed.
2. The method according to claim 1, wherein the acquiring current running state information and surrounding environment information of the own vehicle includes: The running state information of the self vehicle is read through the vehicle-mounted CAN bus, and the running state information comprises the longitudinal speed of the self vehicle Longitudinal acceleration of own vehicle Actual rotation angle of current front wheel of own vehicle And a self vehicle gear state; The method for acquiring the front obstacle information of the self vehicle by utilizing a front-view camera and a forward millimeter wave radar fusion sensing mode comprises the following steps of longitudinally relatively separating the front obstacle from the self vehicle And object type of forward obstacle ; Tracking a rear vehicle in real time by using a rearview camera and a backward millimeter wave radar, and acquiring the longitudinal relative distance between the rear vehicle and the vehicle Longitudinal speed of rear vehicle And a lateral overlap offset of the rear vehicle center and the own vehicle center And according to the longitudinal speed of the own vehicle And the longitudinal speed of the rear vehicle Calculating the relative approach speed of the rear vehicle Together forming rear target vehicle information; Constructing a local environment grid map of the vehicle by using the looking-around camera and the lateral ultrasonic radar, and further identifying the width of a drivable area of an adjacent lane or road shoulder on the left side of the vehicle Width of drivable zone of adjacent lane or road shoulder on right side of own vehicle And obtaining space information of the side lanes.
3. The method according to claim 2, wherein determining whether the own vehicle satisfies a preset state based on the running state information and the forward obstacle information, includes: If the longitudinal speed of the own vehicle is detected Less than a preset longitudinal speed threshold Or the gear state of the self vehicle is neutral, parking gear or brake pedal is pressed, and the self vehicle is judged to be in a static state or a low-speed holding state; detecting a longitudinal relative distance of the forward obstacle from the own vehicle while the own vehicle is in a stationary or low-speed holding state Whether or not it is smaller than a preset safe escape distance threshold While being based on the object type of the forward obstacle Judging the passing impedance attribute of the obstacle, if the passing impedance attribute meets a preset logic condition, judging that the obstacle which prevents the longitudinal escape exists in front of the self vehicle, wherein the self vehicle cannot simply avoid danger through longitudinal acceleration, and the passing is blocked in front.
4. A method according to claim 3, wherein meeting a preset logic condition comprises: And calculating the Boolean logic value of the front traffic jam judgment, wherein the formula for calculating the Boolean logic value of the front traffic jam judgment is as follows: ; Wherein, the A boolean logic value for the calculated forward traffic jam determination; is the longitudinal relative distance of the forward obstacle from the own vehicle; A preset safe escape distance threshold value; For intersection; Object type being a forward obstacle; Is a preset set of non-passable obstacles.
5. The method according to claim 2, wherein when the preset state is satisfied, determining whether the own vehicle has a rear-end collision risk based on the rear target vehicle information, and when the rear-end collision risk exists, determining a risk avoidance direction and a safe lateral region effective width based on the lateral lane space information on the left and right sides of the own vehicle, includes: when the preset state is met, calculating a rear-end collision clamping risk index based on the rear target vehicle information, and if the rear-end collision clamping risk index is larger than a preset risk threshold value Judging that the self vehicle has rear-end collision and rear-end collision clamping risks of front-end and rear-end clamping; When the rear-end collision clamping risk exists, calculating safety grading values of the left side and the right side of the self vehicle based on the side lane space information through a defined side safety grading function; And taking the side with the high safety grading value as the risk avoiding direction so as to determine a target risk avoiding direction mark, and calculating the effective width of a safety lateral area at one side of the risk avoiding direction.
6. The method of claim 5, wherein the step of determining the position of the probe is performed, The formula adopted for calculating the rear-end collision clamping risk index is as follows: ; Wherein, the A rear-end collision clamping risk index; And As a weighting coefficient, the weight for balancing the energy term and the time term; a relative approach speed for a rear vehicle; Is the road adhesion coefficient; Gravitational acceleration; Is the longitudinal relative distance of the own vehicle; Is the collision time; the lateral safety scoring function is expressed as: ; Wherein, the , Is that Side safety score value, when Is that In the time-course of which the first and second contact surfaces, For the left safety score value, when Is that In the time-course of which the first and second contact surfaces, A security score value for the right side; And Respectively the weight coefficients; Is that Width of available space of side, when Is that In the time-course of which the first and second contact surfaces, Width of travelable area for left adjacent lane or road shoulder of own vehicle When (when) Is that In the time-course of which the first and second contact surfaces, Width of travelable area for adjacent lane or road shoulder on right side of own vehicle ; Is that A barrier risk factor on the side, wherein no barrier is 0, and a static barrier is 1; determining a target risk avoiding direction mark, calculating the effective width of a safety lateral area of the side, and expressing the effective width as follows by a formula: ; Wherein, the Identifying a target risk avoiding direction; Is the effective width of the safe lateral area, and the target danger avoiding direction is marked as Corresponding to right safety, the target risk avoiding direction is marked as The corresponding left side is safe; A security score value for the right side; A security score value for the left side; Is a preset minimum value of the security score.
7. The method of claim 2, wherein calculating an optimal yaw guide angle based on the impact moment coupling based on the rear target vehicle information, the determined risk avoidance direction, and the effective width of the safety lateral region, adjusting and locking a front wheel steering angle of the own vehicle to the optimal yaw guide angle, comprises: calculating a reference angle based on a geometric space based on the rear target vehicle information and the safety lateral region effective width; based on the determined risk avoidance direction and the transverse overlapping offset of the center of the rear vehicle and the center of the own vehicle Calculating an impact moment normalization factor; And calculating an optimal deflection guide angle based on the impact moment coupling based on the reference angle based on the geometric space and the impact moment normalization factor, and adjusting and locking the front wheel steering angle of the self vehicle to the optimal deflection guide angle.
8. The method of claim 7, wherein the step of determining the position of the probe is performed, The calculation formula of the reference rotation angle based on the geometric space is as follows: ; Wherein, the Is a reference rotation angle based on a geometric space; A maximum allowable steering angle for a mechanical steering system of the vehicle; the effective width of the safety lateral area is determined; is the length of the body of the own vehicle; Is a velocity correction coefficient; is the longitudinal speed of the rear vehicle; Is a gain coefficient; the calculation formula of the impact moment normalization factor is as follows: ; Wherein, the Normalizing the factor for the impact moment; extracting a function for the symbol; a lateral overlap offset for the center of the rear vehicle and the center of the own vehicle; a target risk avoiding direction mark corresponding to the risk avoiding direction; is the body width of the own vehicle; the calculation formula of the optimal deflection guide angle based on the impact moment coupling is as follows: ; Wherein, the An optimal deflection lead angle for coupling based on the impact moment; is a moment coupling gain coefficient, if Then For positive, if Then Zero.
9. The method according to claim 2, wherein performing a return-to-positive damping proportional-derivative control when the own vehicle is detected to be in a start-slip phase, includes: if the longitudinal acceleration of the own vehicle is detected Is greater than a preset starting threshold And judging that the self vehicle is in a starting escape stage, and calculating a correction moment to execute correction damping proportional-differential control, wherein the calculation formula of the correction moment is as follows: ; Wherein, the Is a correction moment; And Proportional gain and differential gain, respectively; Is the current of the own vehicle the actual rotation angle of the front wheel; the angular velocity of the front wheel of the vehicle; Is the current driver intended turn angle.
10. The method according to claim 1, wherein after issuing the multi-mode warning information for the front wheel deflecting operation performed by the own vehicle, the method further comprises: and if the fact that the self vehicle generates displacement due to the fact that the rear collision is detected, and the self vehicle is judged to be in a stressed moving stage, the optimal deflection guide angle is kept unchanged.

Description

Front wheel pre-deflection-based rear-end collision prevention and clamping danger avoiding method for vehicle Technical Field The invention belongs to the technical field of active safety and intelligent driving control of vehicles, and particularly relates to a rear-end collision prevention and clamping danger avoiding method for vehicles based on front wheel pre-deflection. Background With the increase of urban traffic density and the popularization of intelligent automobiles, a vehicle active safety system plays an important role in reducing accident rate. However, in severe weather such as fog, rain, snow, freezing and the like or in sudden traffic accident scenes, the expressway is extremely prone to multiple-vehicle serial rear-end collision accidents. If the self-vehicle suddenly brakes until the self-vehicle is stationary or slowly moves at a low speed due to the accident or the sudden drop of visibility in front, the front channel is blocked at the moment, and the rear vehicle cannot brake in time due to the blocked sight or the too fast speed of the vehicle, so that the self-vehicle falls into a clamped working condition. The existing active safety method mainly depends on automatic emergency braking or front collision early warning, focuses on coping with front obstacles or simple rear-end collisions, has obvious limitations, namely, for stationary trapped vehicles, simple braking control cannot change physical facts of impacted vehicles, when the front and the rear of the vehicles are rigidly blocked, a longitudinal buffer space is extremely limited, impact energy cannot be effectively dissipated, and the existing risk avoidance logic is mostly based on a dynamic scene of initial speed of the vehicles, lacks escape strategies under the working conditions of 'stall start' or 'passive stress', and is difficult to establish an effective risk avoidance path in an extremely short collision window period. While some studies have introduced automatic emergency steering to attempt to avoid danger by sideways maneuvers, it is still limited to simple planning of geometric space without deep modeling of the kinetic coupling effects during impact. Specifically, existing algorithms tend to treat rear-car collisions as being purely disturbance-resistant, ignoring the large yaw moment created by offset collisions. If the steering direction conflicts with the impact moment direction, impact energy cannot be utilized, and the vehicle can be severely rotated or turned over after being stressed, so that secondary accidents are caused. In addition, the existing decision system lacks consideration on the psychological of a driver, abrupt automatic steering is easy to cause the driver to panic and subconsciously return to the steering wheel, so that danger avoidance failure is caused, yaw stability control in a starting escape stage after collision is not involved, and stable driving of the vehicle into a safe area on a wet road surface is difficult to ensure. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a rear-end collision prevention and clamping danger avoiding method for a vehicle based on front wheel pre-deflection. The technical problems to be solved by the invention are realized by the following technical scheme: A front wheel pre-deflection-based rear-end collision prevention and clamping danger avoiding method for a vehicle comprises the following steps: Acquiring current running state information and surrounding environment information of a vehicle, wherein the surrounding environment information comprises front obstacle information, rear target vehicle information and side lane space information; judging whether the self vehicle meets a preset state or not based on the running state information and the front obstacle information, wherein the preset state is that the self vehicle is in a static state or a low-speed holding state and a front passing blocking condition exists; Judging whether the self vehicle has a rear-end collision clamping risk or not based on the rear target vehicle information when the preset state is met, and deciding a risk avoiding direction and the effective width of a safety lateral area based on the lateral lane space information on the left side and the right side of the self vehicle when the rear-end collision clamping risk exists; Calculating an optimal deflection guide angle based on impact moment coupling based on the rear target vehicle information, the decided risk avoiding direction and the effective width of the safety lateral area, and adjusting and locking the front wheel steering angle of the vehicle to the optimal deflection guide angle; Sending out multi-mode warning information for front wheel deflection operation executed by the self vehicle; when the own vehicle is detected to be in a start escape phase, a return positive damping proportional-differential control is performed. In one embodiment of the present inve