CN110987485B - Automatic calibration method for transmission ratio of steering wheel - Google Patents
Automatic calibration method for transmission ratio of steering wheel Download PDFInfo
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- CN110987485B CN110987485B CN201911239867.1A CN201911239867A CN110987485B CN 110987485 B CN110987485 B CN 110987485B CN 201911239867 A CN201911239867 A CN 201911239867A CN 110987485 B CN110987485 B CN 110987485B
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Abstract
The invention discloses an automatic calibration method of a steering wheel transmission ratio, which comprises the following steps: selecting a test area, drawing a straight line on the ground, and stopping the vehicle along the straight line in an initial state; connecting the automatic parking device with an OBD interface of the whole vehicle through CAN-high and CAN-low, and starting the automatic parking device to calibrate the transmission ratio of the steering wheel; a calibration worker selects a target angle theta to be calibrated, and the automatic parking device sends the target angle theta to the EPS through the CAN bus; the vehicle runs at low speed, when the vehicle body rotates 180 degrees, the vehicle stops, the distance L between the rear wheel and the initial position at the moment is measured, and the turning radius R is calculated; calculating a vehicle front wheel steering angle alpha corresponding to the current target angle: α = atan (l)0/R) in which l0The wheelbase of the vehicle, R is the turning radius; the method comprises the following steps that a steering wheel transmission ratio I = a target angle theta/a front wheel rotation angle alpha of a vehicle corresponding to a current calibrated target angle; and then, verifying the result. The automatic calibration method for the transmission ratio of the steering wheel disclosed by the invention has the advantages that the human error is effectively reduced, and the safety coefficient is high.
Description
Technical Field
The invention relates to an automatic calibration method for a transmission ratio of a steering wheel, and belongs to the technical field of automobile control systems.
Background
At present, the mainstream automatic parking systems in the market have the basic function of parking, but the parking effect is good and different, and the work of calibrating the transmission ratio of a steering wheel must be accurately finished to obtain a better parking effect.
The existing transmission ratio calibration mode needs calibration personnel to manually control different steering wheel angles and monitor the steering wheel angles in real time through a computer screen so as to control angle errors, the calibration mode has certain errors, debugging personnel hold the steering wheel for a long time to keep a fixed angle, the working strength is high, and the debugging personnel need to keep eyes on the computer screen all the time in order to control the angle errors of the steering wheel during calibration, so that the front condition of a vehicle cannot be observed, and potential safety hazards exist.
Meanwhile, the existing transmission ratio calibration mode depends on the subjective feeling of a debugging person, and the steering performance is influenced by various factors such as EPS control parameters and vehicle conditions, so that the calibrated transmission ratio parameters are matched on one trolley and are not applicable to another trolley, and the final parking performance is not ideal.
Disclosure of Invention
The purpose is as follows: in order to overcome the defects in the prior art, the invention provides an automatic calibration method for the transmission ratio of a steering wheel.
The technical scheme is as follows: in order to solve the technical problems, the technical scheme adopted by the invention is as follows:
an automatic calibration method for the transmission ratio of a steering wheel comprises the following steps: selecting a test area, drawing a straight line on the ground, and stopping the vehicle along the straight line in an initial state; the automatic parking device is connected with an OBD interface of the whole vehicle through CAN-high and CAN-low, and the automatic parking device is started to automatically calibrate the transmission ratio of the steering wheel;
a calibration worker selects a target angle theta to be calibrated, the automatic parking device sends the target angle theta to the EPS through the CAN bus, and the target angle theta is a steering wheel rotation angle; the method comprises the following steps that a vehicle runs at the speed of 2-5 km/h, stops when the vehicle body rotates by 180 degrees, measures the distance L between the position of a rear wheel at the moment and the position of the rear wheel in an initial state, and calculates the turning radius R;
calculating a vehicle front wheel steering angle alpha corresponding to the current target angle: α = atan (l)0/R) in which l0The wheelbase of the vehicle, R is the turning radius; the method comprises the following steps that a steering wheel transmission ratio I = a target angle theta/a front wheel rotation angle alpha of a vehicle corresponding to a current calibrated target angle;
and (5) result verification: the turning radius difference Δ R = actually calculated turning radius R-turning radius R calculated by the automatic parking device,
the rotation angle difference delta beta = the rotation angle beta-180 deg. of the car body calculated by the automatic parking device,
when the | < 50mm and | < 1 °, the calibration result meets the requirement, the value of the front wheel turning angle α of the vehicle corresponding to the target angle θ is updated into the software of the automatic parking device, and the automatic parking device corrects the result of the turning radius calculated by the automatic parking device;
and if the calibration result does not meet the requirements of | R | < 50mm and | β | < 1 ° after verification, the gear ratio calibration at the target angle needs to be carried out again until the requirements are met.
Further, the CAN bus communication rate is 500 kbaud.
Further, in the initial state, the front and rear tire edges on one side coincide with the straight line when the vehicle stops.
Further, in the driving process of the vehicle, the EPS controls the steering wheel to be locked, and hands of a calibration person leave the steering wheel.
Further, a method of judging that a body of a vehicle is rotated by 180 °: drawing a plurality of parallel straight lines on the ground of the test area, and stopping the vehicle along one of the straight lines in an initial state; the vehicle runs at a low speed at a target angle theta, stops when the vehicle is about to be parallel to the straight line of the test area again through visual inspection, measures the distances between the front wheels and the rear wheels on the same side and the straight line closest to the vehicle, and judges that the vehicle just rotates 180 degrees if the distances are equal; if the rotating angle of the vehicle body does not reach 180 degrees after measurement, the vehicle is controlled to move forwards until the distances between the front wheels and the rear wheels on the same side and the straight line closest to the vehicle are equal; if the angle that the automobile body turned through is judged to exceed 180 degrees after measurement, the automobile needs to be driven back to the starting point and turned for 180 degrees again.
Further, the target angle θ is sequentially decreased by a gradient of 30 ° starting from the maximum angle to which the steering wheel can be actually turned, and then the gear ratio of the steering wheel at each target angle is calibrated.
Has the advantages that: the automatic calibration method for the transmission ratio of the steering wheel provided by the invention effectively reduces the errors caused by human factors in the calibration process, and the calibration personnel do not need to hold the steering wheel all the time in the process, so that the stability of the steering wheel is kept, the calibration efficiency is improved, and meanwhile, the calibration personnel do not need to keep eyes always aiming at the target angle displayed on a computer screen to manually and dynamically adjust the angle, so that the angle error is prevented from being larger, and the potential safety hazard can be effectively reduced.
Drawings
FIG. 1 is a schematic view of a vehicle during calibration turning 180;
FIG. 2 is a schematic view of a vehicle turning angle at a target angle;
FIG. 3 shows the results of the calibration of the steering wheel gear ratio at different target angles.
Detailed Description
The present invention will be further described with reference to the accompanying drawings.
An automatic calibration method for the transmission ratio of a steering wheel comprises the following steps:
selecting a test area, drawing a plurality of parallel straight lines on the ground, and stopping the vehicle along one of the straight lines in an initial state, namely, the front and rear tire edges on one side are overlapped with the straight line; the automatic parking device is connected with an OBD interface of the whole vehicle through CAN-high and CAN-low, the automatic parking device is started to automatically calibrate the transmission ratio of a steering wheel, and the automatic parking device CAN select an automatic parking system and app in the prior art;
a calibration worker selects a target angle theta to be calibrated, the automatic parking device sends the target angle theta to the EPS through the CAN bus, and the target angle theta is a steering wheel rotation angle; the CAN bus communication rate is 500 kbaud. The method comprises the following steps that a vehicle runs at the speed of 2-5 km/h, in the running process of the vehicle, an EPS (electric Power storage) controls a steering wheel to rotate and keep an angle theta and lock, and hands of a calibration worker can leave the steering wheel; when the vehicle body is stopped after rotating 180 degrees, the distance L between the position of the rear wheel at the moment and the position of the rear wheel in the initial state is measured, as shown in FIG. 1, the rear wheel on the right side of the vehicle is taken as a measurement object, the rear wheel in the initial state reaches a point B after rotating 180 degrees at a point A, L is the distance between the two points A, B, and then the turning radius R, R = (L + D)/2 is calculated, wherein D is the width of the vehicle body.
The method for judging that the body of the vehicle rotates 180 degrees comprises the following steps: the vehicle runs at a low speed under a target angle theta, the vehicle is stopped when being parallel to the straight line of the test area again by visual inspection, the distances between the front wheels and the rear wheels on the same side and the straight line closest to the vehicle are measured, and if the distances are equal, the vehicle is judged to just rotate 180 degrees; if the angle of the vehicle body rotated by the angle sensor does not reach 180 degrees after measurement, the vehicle is controlled to move forwards until the distances between the front wheels and the rear wheels on the same side and the straight line closest to the vehicle are equal, and if the angle of the vehicle body rotated by the angle sensor exceeds 180 degrees after measurement, the vehicle is required to move back to the starting point and rotate by 180 degrees again.
Calculating a vehicle front wheel steering angle alpha corresponding to the current target angle: α = atan (l)0/R) in which l0R is the turning radius, which is the wheelbase of the vehicle, as shown in FIG. 2.
And the current calibrated target angle corresponds to a steering wheel transmission ratio I = a target angle theta/a front wheel rotation angle alpha of the vehicle.
And (5) result verification: the turning radius difference Δ R = actually calculated turning radius R-turning radius R calculated by the automatic parking device,
the rotation angle difference delta beta = the rotation angle beta-180 deg. of the car body calculated by the automatic parking device,
when | < 50mm and | Δ β | < 1 °, the calibration result meets the requirement, the value of the vehicle front wheel turning angle α corresponding to the target angle θ is updated to the software of the automatic parking device, and the automatic parking device corrects the result of the turning radius calculated by the automatic parking device.
And if the calibration result does not meet the requirements of | R | < 50mm and | β | < 1 ° after verification, the gear ratio calibration at the target angle needs to be carried out again until the requirements are met.
The target angle theta is from the maximum angle that the steering wheel can actually rotate, the target angle theta is sequentially reduced by taking 30 degrees as a gradient, and then the transmission ratio of the steering wheel at each target angle is calibrated. In this embodiment, the target rotation angle θ is decreased from 550 °, and includes 550 °, 520 °, 490 °, 460 °, 430 °, …, 250 °, 220 °, and 12 target angle values, and the result of gear ratio calibration of each target angle is shown in fig. 3.
The calibration is carried out in the direction of 'forward right' of the automobile, and after the calibration is finished, the calibration is carried out in three directions of 'forward left', backward left 'and backward right', so that the calibration is carried out on 12 × 4=48 target angles in total.
The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.
Claims (6)
1. An automatic calibration method for the transmission ratio of a steering wheel is characterized in that: the method comprises the following steps:
selecting a test area, drawing a straight line on the ground, and stopping the vehicle along the straight line in an initial state; the automatic parking device is connected with an OBD interface of the whole vehicle through CAN-high and CAN-low, and the automatic parking device is started to automatically calibrate the transmission ratio of the steering wheel;
a calibration worker selects a target angle theta to be calibrated, the automatic parking device sends the target angle theta to the EPS through the CAN bus, and the target angle theta is a steering wheel rotation angle; the method comprises the following steps that a vehicle runs at the speed of 2-5 km/h, stops when the vehicle body rotates by 180 degrees, measures the distance L between the position of a rear wheel and the position of the rear wheel in an initial state at the moment, and then calculates the turning radius R;
calculating a vehicle front wheel steering angle alpha corresponding to the current target angle: α = atan (l)0/R) in which l0The wheelbase of the vehicle, R is the turning radius; the method comprises the following steps that a steering wheel transmission ratio I = a target angle theta/a front wheel rotation angle alpha of a vehicle corresponding to a current calibrated target angle;
and (5) result verification: the turning radius difference Δ R = the actually calculated turning radius R-the turning radius R' calculated by the automatic parking device,
the rotation angle difference delta beta = the rotation angle beta-180 deg. of the car body calculated by the automatic parking device,
when the | < 50mm and | < 1 °, the calibration result meets the requirement, the value of the front wheel turning angle α of the vehicle corresponding to the target angle θ is updated into the software of the automatic parking device, and the automatic parking device corrects the result of the turning radius calculated by the automatic parking device;
and if the calibration result does not meet the requirements of | R | < 50mm and | β | < 1 ° after verification, the gear ratio calibration at the target angle needs to be carried out again until the requirements are met.
2. The automatic calibration method for the transmission ratio of the steering wheel according to claim 1, characterized in that: the CAN bus communication rate is 500 kbaud.
3. The automatic calibration method for the transmission ratio of the steering wheel according to claim 1, characterized in that: in the initial state, the front and rear tire edges on one side coincide with the straight line when the vehicle stops.
4. The automatic calibration method for the transmission ratio of the steering wheel according to claim 1, characterized in that: in the driving process of the vehicle, the EPS controls the steering wheel to be locked, and hands of a calibrated person leave the steering wheel.
5. The automatic calibration method for the transmission ratio of the steering wheel according to claim 1, characterized in that: the method for judging that the body of the vehicle rotates 180 degrees comprises the following steps: drawing a plurality of parallel straight lines on the ground of the test area, and stopping the vehicle along one of the straight lines in an initial state; the vehicle runs at a low speed under a target angle theta, the vehicle is stopped when being parallel to the straight line of the test area again by visual inspection, the distances between the front wheels and the rear wheels on the same side and the straight line closest to the vehicle are measured, and if the distances are equal, the vehicle is judged to just rotate 180 degrees; if the vehicle body is judged to rotate by less than 180 degrees after measurement, the vehicle is controlled to move forwards until the distances between the front wheels and the rear wheels on the same side and the straight line closest to the vehicle are equal; if the angle that the automobile body turned through is judged to exceed 180 degrees after measurement, the automobile needs to be driven back to the starting point and turned for 180 degrees again.
6. The automatic calibration method for the transmission ratio of the steering wheel according to claim 1, characterized in that: the target angle theta is from the maximum angle that the steering wheel can actually rotate, the target angle theta is sequentially reduced by taking 30 degrees as a gradient, and then the transmission ratio of the steering wheel at each target angle is calibrated.
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| CN112092818A (en) * | 2020-08-24 | 2020-12-18 | 奇瑞新能源汽车股份有限公司 | Road curvature radius calculation method and device of blind area monitoring system and vehicle |
| CN112212887B (en) * | 2020-08-27 | 2022-07-05 | 武汉乐庭软件技术有限公司 | Automatic parking positioning parameter calibration method based on Ackerman steering model |
| CN112344960B (en) * | 2020-10-23 | 2022-12-13 | 上海拿森汽车电子有限公司 | IMU signal checking method and device and vehicle |
| CN113624520B (en) * | 2021-07-29 | 2023-05-16 | 东风汽车集团股份有限公司 | System, method and medium for calculating vehicle understeer gradient coefficient in real time based on machine vision technology |
| CN113899564A (en) * | 2021-10-12 | 2022-01-07 | 深圳市道通智能汽车有限公司 | Measuring method, measuring device, computer equipment and storage medium |
| CN114112445B (en) * | 2021-12-31 | 2024-04-02 | 杭州海康汽车软件有限公司 | Method, device, system, equipment and medium for calibrating steering wheel steering transmission ratio |
| CN116990045B (en) * | 2023-05-18 | 2024-04-05 | 运来智能装备(无锡)有限公司 | Drive-by-wire chassis scale factor calibration method, system and medium based on inertial measurement |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1826099A2 (en) * | 2006-02-22 | 2007-08-29 | WABCO GmbH | Method for determining the steering ratio of a vehicle |
| CN106769114A (en) * | 2017-03-06 | 2017-05-31 | 吉林大学 | Motor turning gearratio measurement apparatus and method |
| CN106740866A (en) * | 2016-11-28 | 2017-05-31 | 南京安驾信息科技有限公司 | The computational methods and device of a kind of steering wheel angle |
| CN107702928A (en) * | 2017-09-26 | 2018-02-16 | 吉林大学 | A kind of pivoted wheels on vehicle corner measuring apparatus and method |
| CN108731951A (en) * | 2018-04-11 | 2018-11-02 | 安徽江淮汽车集团股份有限公司 | Motor turning angular gear ratio examines equipment |
| CN110487564A (en) * | 2019-08-26 | 2019-11-22 | 铱斯电子科技(上海)有限公司 | Steering wheel transmission ratio automatic calibration method |
-
2019
- 2019-12-06 CN CN201911239867.1A patent/CN110987485B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1826099A2 (en) * | 2006-02-22 | 2007-08-29 | WABCO GmbH | Method for determining the steering ratio of a vehicle |
| CN106740866A (en) * | 2016-11-28 | 2017-05-31 | 南京安驾信息科技有限公司 | The computational methods and device of a kind of steering wheel angle |
| CN106769114A (en) * | 2017-03-06 | 2017-05-31 | 吉林大学 | Motor turning gearratio measurement apparatus and method |
| CN107702928A (en) * | 2017-09-26 | 2018-02-16 | 吉林大学 | A kind of pivoted wheels on vehicle corner measuring apparatus and method |
| CN108731951A (en) * | 2018-04-11 | 2018-11-02 | 安徽江淮汽车集团股份有限公司 | Motor turning angular gear ratio examines equipment |
| CN110487564A (en) * | 2019-08-26 | 2019-11-22 | 铱斯电子科技(上海)有限公司 | Steering wheel transmission ratio automatic calibration method |
Non-Patent Citations (1)
| Title |
|---|
| 转向系统5轴性能试验台测试方法研究;任志鹏;《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》;20180215(第02期);全文 * |
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