CN-121989914-A - Vehicle deviation adjustment method based on road cross slope

CN121989914ACN 121989914 ACN121989914 ACN 121989914ACN-121989914-A

Abstract

The application relates to a vehicle deviation adjustment method based on a road cross slope, which belongs to the technical field of automobiles and comprises the steps of controlling a vehicle to run along a straight line on a target road with a preset cross slope, enabling a steering system of the vehicle to be in a free state after the vehicle speed reaches the target speed so as to enable the vehicle to run freely, recording actual measurement time length which is passed from the moment that the steering system of the vehicle is in the free state to the moment that the transverse deviation reaches a preset distance, comparing the actual measurement time length with a preset threshold value, increasing the caster angle of a kingpin of a wheel positioned on the lower side of the road in a front axle of the vehicle if the actual measurement time length is smaller than the preset threshold value, and repeating the steps until the actual measurement time length is longer than or equal to the preset threshold value. The method can improve the vehicle adjustment efficiency, obviously enhance the linear stability of the vehicle when the vehicle runs on the domestic road with a typical transverse slope, effectively inhibit the deviation phenomenon and improve the driving comfort and the driving safety.

Inventors

YANG XIAOJIAN
DU XIYANG
LI QIAN
LI ANYUAN
WANG QIANG
GENG YINGDONG

Assignees

东风商用车有限公司

Dates

Publication Date: 20260508
Application Date: 20260312

Claims (10)

1. A vehicle deviation adjustment method based on a road cross slope is characterized by comprising the following steps: Controlling the vehicle to run along a straight line on a target road with a preset transverse slope, and enabling a steering system of the vehicle to be in a free state after the vehicle speed reaches the target speed so as to enable the vehicle to run freely; recording the actual measurement time length from the moment when the steering system of the vehicle is in a free state to the moment when the transverse deviation of the vehicle reaches a preset distance; Comparing the measured time length with a preset threshold value; If the measured time length is smaller than a preset threshold value, the caster angle of the wheel positioned on the lower side of the road in the front axle of the vehicle is increased, and the steps are repeated until the measured time length is larger than or equal to the preset threshold value.
2. The method for adjusting the deviation of a vehicle based on a road cross slope according to claim 1, wherein: The enabling the steering system of the vehicle to be in a free state comprises: under the condition that the steering system of the vehicle is free from external force intervention, the front wheels are allowed to freely deflect along with the feedback of the road surface according to the positioning parameters of the vehicle; the steering system is characterized in that no external force intervention is realized by loosening a steering wheel by a driver or by controlling the steering system to enter a zero-moment follow-up mode by an automatic driving system.
3. The method for adjusting the deviation of a vehicle based on a road cross slope according to claim 1, wherein: The preset threshold value is determined according to the preset distance and the transverse slope angle data of the target road, and corresponds to the time required by the vehicle to deviate the preset distance at the allowable transverse deviation speed on the target road corresponding to the transverse slope angle data.
4. The method for adjusting the deviation of a vehicle based on a road cross slope according to claim 1, wherein: increasing a caster of a wheel located on a low side of a road in a front axle of the vehicle, comprising: and increasing the back inclination angle of the main pin hole positioned on the lower side of the road in the front axle of the vehicle and/or increasing the front inclination angle of the spring support surface positioned on the lower side of the road in the front axle of the vehicle.
5. The method for adjusting the deviation of a vehicle based on a road cross slope according to claim 1 or 4, wherein: increasing a caster of a wheel located on a low side of a road in a front axle of the vehicle, comprising: and determining the adjustment increment of the caster angle of the kingpin according to the difference value between the preset threshold value and the actually measured time length, wherein the adjustment increment and the difference value are in positive correlation, and the larger the difference value is, the larger the adjustment increment is.
6. The method for adjusting the deviation of a vehicle based on a road cross slope according to claim 5, wherein: determining a tuning increment corresponding to the difference value based on a preset mapping relation; the mapping relation comprises at least two different difference intervals, and corresponding adjustment increment is respectively configured for each difference interval; for any two difference intervals, the increment of the adjustment corresponding to the difference interval with larger value is larger than that of the adjustment corresponding to the difference interval with smaller value.
7. The method for adjusting the deviation of a vehicle based on a road cross slope according to claim 1, wherein: And after the vehicle speed reaches the target speed, controlling the vehicle to linearly travel at a constant speed along the target road for a preset stabilizing distance at the target speed so as to ensure that the vehicle reaches a constant-speed traveling state when the steering system of the vehicle is in a free state.
8. The method for adjusting the deviation of a vehicle based on a road cross slope according to claim 1, wherein: The recording of the actual measurement time period that the vehicle experiences until the lateral deviation reaches a preset distance from the moment when the steering system of the vehicle is in a free state, includes: Taking the moment that the steering system of the vehicle is in a free state and the left front wheel of the vehicle is pressed on the left lane line as a timing starting point; Taking the moment that the right front wheel of the vehicle presses to the right lane line as a timing end point; And recording the time from the timing starting point to the timing ending point as the actual measurement duration.
9. The method for adjusting the deviation of a vehicle based on a road cross slope according to claim 1, wherein: before the vehicle travels on the target road, further comprising: Acquiring the transverse slope angle data of the target road; And presetting initial camber angles of wheels at the left side and the right side of a front axle of the vehicle according to the transverse slope angle data so that the camber angles of the wheels are matched with the transverse slope of the road when the vehicle runs on the target road.
10. The method for adjusting the deviation of a vehicle based on a road cross slope according to claim 9, wherein: The camber angle initial value of the wheels at the left side and the right side of the front axle of the preset vehicle comprises: Acquiring a tire footprint of a vehicle on the target road; Calculating the squaring rate of the tire footprint, wherein the squaring rate is used for representing the approaching degree of the shape of the footprint and an ideal rectangle; And adjusting the caster angle of the front axle of the vehicle according to the deviation of the squaring rate and the target squaring rate range so as to change the camber angle initial value until the squaring rate falls into a preset target range.

Description

Vehicle deviation adjustment method based on road cross slope Technical Field The application relates to the technical field of automobiles, in particular to a vehicle deviation adjustment method based on a road cross slope. Background At present, domestic vehicles run on the right side of a road for left rudder running. In national roads and highways, the road surface is usually designed into a bidirectional transverse slope structure with high middle and low two sides, and the transverse slope of water drainage is usually set to 15' (about 0.25 degrees). This means that the vehicle is on a road surface with a certain lateral inclination for a long period of time during actual running, resulting in that the vehicle posture cannot be kept perfectly centered. In the prior art, the positioning parameters of the front axle of a vehicle are usually designed to be bilaterally symmetrical. For example, the caster angles of the wheels on the left and right sides of the front axle are designed to be the same value so that the magnitude of the camber angles of the left and right wheels are equal. However, when the vehicle is running on a road surface having a lateral slope, the contact state of the ground contact surfaces of the tires on the left and right sides with respect to the ground varies due to the inclination of the ground, so that the squareness of the tire footprint cannot be achieved at the same time. If the squaring rate of the tire footprint is low, tire shoulder bias wear can occur, affecting the service life of the tire. In addition, the caster angles of the wheels on the left and right sides of the front axle are also typically designed to be the same. When the vehicle runs on the road surface with the transverse slope, the vehicle is inevitably deflected to the lower side of the slope due to the action of gravity component force, namely, the vehicle deviation phenomenon is generated. The deviation not only affects driving experience, but also can aggravate uneven wear of tires and reduce driving safety. Therefore, it is necessary to provide a vehicle deviation adjustment method based on a road cross slope in order to solve the above problems. Disclosure of Invention Aiming at one of the defects or shortcomings of the background technology, the embodiment of the application provides a vehicle deviation adjustment method based on a road cross slope, which aims to solve the problem that in the related art, the vehicle is easy to generate deviation when running on the cross slope road due to the bilateral symmetry design of front axle positioning parameters. The embodiment of the application provides a vehicle deviation adjustment method based on a road cross slope, which comprises the following steps: S1, controlling a vehicle to run along a straight line on a target road with a preset transverse slope, and enabling a steering system of the vehicle to be in a free state after the vehicle speed reaches the target speed so as to enable the vehicle to run freely; S2, starting from the moment that the steering system of the vehicle is in a free state, recording the actual measurement time length which is experienced when the vehicle reaches the preset distance to the transverse deviation; S3, comparing the actually measured time length with a preset threshold value; and S4, if the actual measurement time length is smaller than a preset threshold value, increasing the caster angle of the wheel positioned on the lower side of the road in the front axle of the vehicle, and repeating the steps until the actual measurement time length is larger than or equal to the preset threshold value. In some embodiments, the placing the steering system of the vehicle in a free state includes: under the condition that the steering system of the vehicle is free from external force intervention, the front wheels are allowed to freely deflect along with the feedback of the road surface according to the positioning parameters of the vehicle; the steering system is characterized in that no external force intervention is realized by loosening a steering wheel by a driver or by controlling the steering system to enter a zero-moment follow-up mode by an automatic driving system. In some embodiments, the preset threshold is determined according to the preset distance and the lateral slope angle data of the target road, where the preset threshold corresponds to a time required for the vehicle to deviate from the preset distance at an allowable lateral deviation speed on the target road corresponding to the lateral slope angle data. In some embodiments, increasing the caster of wheels of the front axle of the vehicle on the lower side of the roadway comprises: and increasing the back inclination angle of the main pin hole positioned on the lower side of the road in the front axle of the vehicle and/or increasing the front inclination angle of the spring support surface positioned on the lower side of the road in the front axle of the