Automatic meso-position calibration method and device for commercial light truck

Abstract

The invention discloses an automatic neutral position calibration method and device for a commercial light truck, and the method comprises the steps: receiving a first front axle turning angle signal and a first steering wheel turning angle signal in real time under the driving state of a vehicle; if the error between the first front axle turning angle signal and the first steering wheel turning angle signal is larger than or equal to a turning angle threshold value, a wakeup instruction for automatic neutral position calibration is sent to an electric steering gear controller, so that the electric steering gear controller responds to the wakeup instruction to keep the vehicle to run linearly; sequentially receiving a calibration starting signal and a calibration ending signal of the electric steering gear controller; calculating linear coefficients of a second front axle turning angle signal and a second steering wheel turning angle signal collected in the calibration process, and taking the linear coefficients as calibration coefficients. According to the method, the neutral position is recalibrated in time under the condition that manual interference is not needed, and the situation that the vehicle deviates during running is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of commercial light trucks, and more specifically, to an automatic center position calibration method and device for commercial light trucks. Background Art

[0002] At present, the steering system of commercial vehicles and light trucks adopts an electric power steering system, and the steering gear is an electric recirculating ball steering gear. When the vehicle is produced and the four-wheel alignment is completed, the coordinates of the hard points of the steering system change due to assembly errors, which will cause the left and right consistency of the electric steering gear torque and steering angle signals to deviate, and the vehicle will deviate. To solve the above situation, it is necessary to perform a mid-position calibration on the torque signal and steering signal of the electric recirculating ball steering gear.

[0003] In the prior art, after the vehicle is produced and the four-wheel alignment is completed, the vehicle is driven straight on a flat road for more than 100 meters, then the vehicle is stopped and the ignition switch of the vehicle is turned off. At this time, the wheels are in a straight driving position, and the ignition switch can be operated for initial center calibration. The steering wheel cannot be turned or touched during the entire calibration process. The operation process is as follows:

[0004] First, turn off the engine and wait for 6 seconds. Turn the ignition switch to the ON position so that the instrument panel lights up. Then, complete 5 or more consecutive switches within 7 seconds, i.e., ON-ACC-ON-ACC-ON-ACC-ON-ACC-ON-ACC. Turn off the engine and wait for 3 seconds. Turn on the ignition and start the vehicle to READY. If the power assistance is normal and the EPS light is off, the calibration is successful.

[0005] However, after the center calibration is completed, during the use of the vehicle, due to uneven load, stress relief of components, overload motion interference exceeding the required value, inconsistent tire pressure on the left and right tires, or due to increased clearance at various joints of the steering system, increased free clearance of the steering column, steering gear, steering tie rod and front axle, the marked center position deviates from the actual center position, causing the vehicle to run off course. However, at this time, the initial center calibration method cannot be used to achieve recalibration. Summary of the invention

[0006] The present application provides a method and device for automatic center calibration of a commercial light truck, which utilizes a vehicle controller to automatically determine the conditions for center calibration and automatically control the center calibration process. The automatic calibration process can be performed while the vehicle is in motion, thereby timely recalibrating the center position without manual intervention, thereby preventing the vehicle from deviating from the track.

[0007] The present application provides an automatic center calibration method for a commercial light truck, which is applicable to a vehicle controller. The automatic center calibration method includes:

[0008] When the vehicle is in a driving state, receiving a first front axle angle signal and a first steering wheel angle signal in real time;

[0009] calculating an error between a first front axle angle signal and a first steering wheel angle signal;

[0010] If the error is greater than or equal to the turning angle threshold, a wake-up command for automatic center calibration is sent to the electric steering gear controller, so that the electric steering gear controller keeps the vehicle moving in a straight line in response to the wake-up command;

[0011] receiving a calibration start signal and a calibration end signal from an electric steering gear controller in sequence;

[0012] The linear coefficients of the second front axle angle signal and the second steering wheel angle signal collected during the calibration process are calculated, and the linear coefficients are used as calibration coefficients.

[0013] Preferably, the time interval of the calibration process is a preset duration.

[0014] Preferably, the automatic center position calibration method for a commercial light truck further includes:

[0015] sending an indicator light on command to the instrument in response to receiving a calibration start signal;

[0016] In response to receiving the calibration end signal, an indicator light off instruction is sent to the instrument.

[0017] Preferably, if the error is less than the turning angle threshold, a sleep instruction for automatic neutral calibration is sent to the electric steering gear controller.

[0018] Preferably, the color of the indicator light during the automatic center calibration process is different from the color of the indicator light during the initial center calibration.

[0019] The present application also provides an automatic center position calibration device for a commercial light truck, comprising a first receiving module, a first calculating module, a first instruction sending module, a second receiving module and a second calculating module;

[0020] The first receiving module is used to receive a first front axle angle signal and a first steering wheel angle signal in real time when the vehicle is in a driving state;

[0021] The first calculation module is used to calculate the error between the first front axle angle signal and the first steering wheel angle signal;

[0022] The first instruction sending module is used for sending a wake-up instruction of automatic neutral calibration to the electric steering gear controller when the error is greater than or equal to the turning angle threshold, so that the electric steering gear controller keeps the vehicle running in a straight line in response to the wake-up instruction;

[0023] The second receiving module is used to sequentially receive a calibration start signal and a calibration end signal of the electric steering gear controller;

[0024] The second calculation module is used to calculate the linear coefficients of the second front axle angle signal and the second steering wheel angle signal collected during the calibration process, and use the linear coefficients as calibration coefficients.

[0025] Preferably, the time interval of the calibration process is a preset duration.

[0026] Preferably, the automatic center calibration device for commercial light trucks also includes a second instruction sending module, which is used to send an indicator light on instruction to the instrument in response to receiving a calibration start signal, and send an indicator light off instruction to the instrument in response to receiving a calibration end signal.

[0027] Preferably, the first instruction sending module is used to send a sleep instruction for automatic neutral position calibration to the electric steering gear controller when the error is less than the turning angle threshold.

[0028] Preferably, the color of the indicator light during the automatic center calibration process is different from the color of the indicator light during the initial center calibration.

[0029] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0031] Figure 1 A flow chart of an automatic center calibration method for a commercial light truck provided in this application;

[0032] Figure 2 This is a structural diagram of the automatic center position calibration device for a commercial light truck provided in this application. DETAILED DESCRIPTION

[0033] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0034] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0035] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0036] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0037] The present application provides a method and device for automatic center calibration of a commercial light truck, which utilizes a vehicle controller to automatically determine the conditions for center calibration and automatically control the center calibration process. The automatic calibration process can be performed while the vehicle is in motion, thereby timely recalibrating the center position without manual intervention, thereby preventing the vehicle from deviating from the track.

[0038] In commercial light truck models, when the vehicle is off the assembly line, the front axle angle R1×the transmission ratio i of the electric steering gear w × coefficient n = steering wheel angle R2, where the transmission ratio of the electric steering gear is i w And the coefficient n is a constant, so the front axle angle R1 and the steering wheel angle R2 are in direct proportion.

[0039] After the vehicle completes the steering center calibration, when the vehicle is driving in a straight line, the front axle angle R1 and the steering wheel angle R2 form the required fixed value relationship. After the vehicle has been used for a period of time, due to uneven load, component stress relief, overloading, and inconsistent tire pressure on the left and right tires, the deformation of the steering system's rod system exceeds the electric steering gear's center angle range, resulting in an error between the marked center and the actual center, and the vehicle deviates from the vehicle; or, the gaps at the joints of the steering system increase, and the free gaps of the steering column, steering gear, steering tie rod and front axle increase, resulting in a deviation between the marked center and the actual center, causing the vehicle to deviate from the vehicle. At this time, the fixed value relationship between the front axle angle and the steering wheel angle changes, and the driver needs to turn the steering wheel a certain angle to keep the vehicle in a straight driving state. It has been verified that when the error between the two exceeds the angle threshold (for example, 30'), the vehicle will deviate from the vehicle.

[0040] The automatic center calibration method for commercial light trucks provided in this application is applicable to the vehicle controller. Figure 1 As shown, the automatic median calibration method includes:

[0041] S110: When the vehicle is in a driving state (ie, after the vehicle has completed initial mid-position calibration), a first front axle angle signal acquired by a front axle wheel end angle sensor and a first steering wheel angle signal acquired by an electric steering gear angle sensor are received in real time.

[0042] S120: Calculate an error between the first front axle angle signal and the first steering wheel angle signal.

[0043] S130: Determine whether the error is greater than or equal to the turning angle threshold. If yes, execute S140; otherwise, execute S170.

[0044] S140: Sending a wake-up command for automatic center calibration to the electric steering controller, so that the electric steering controller starts the automatic center calibration function in response to the wake-up command, and keeps the vehicle moving in a straight line after starting the automatic center calibration function. At this time, the electric steering controller forcibly controls the steering wheel angle to be fixed and is not affected by the driver's operation of the steering wheel. The angle keeps the vehicle moving straight, and the front axle angle is theoretically unchanged at this time. It can be understood that since the calibration process is very fast (see the following description), the fixed steering wheel angle in a short period of time will not affect the driving safety of the vehicle.

[0045] During the automatic center calibration process, the vehicle controller continuously receives the second front axle angle signal collected by the front axle wheel end angle sensor and the second steering wheel angle signal collected by the electric steering gear angle sensor. Since the vehicle keeps going straight, in theory, the second front axle angle signal and the second steering wheel angle signal remain unchanged.

[0046] Preferably, when the error is greater than or equal to the angle threshold and the vehicle speed is greater than the vehicle speed threshold (for example, 40 km / h), a wake-up command for automatic center calibration is sent to the electric steering gear controller. The vehicle has higher stability at higher speeds, and the fluctuations of the second front axle angle signal and the second steering wheel angle signal are smaller, thereby improving the accuracy of automatic center calibration.

[0047] S150: receiving the calibration start signal and the calibration end signal of the electric steering gear controller in sequence. After the electric steering gear controller sends the calibration end signal, its automatic center position calibration function enters a dormant state.

[0048] Preferably, the time interval of the calibration process is a preset time length (eg, 3"), and the automatic center calibration is completed in a very short time, ensuring that straight-line driving in a short time does not affect driving safety.

[0049] Preferably, after receiving the calibration start signal, the vehicle controller sends an indicator light turn-on command to the instrument; and after receiving the calibration end signal, it sends an indicator light turn-off command to the instrument, thereby prompting the driver through the indicator light that the vehicle is in the automatic neutral calibration state and no steering wheel operation is performed within a preset time.

[0050] As an embodiment, when the instrument receives an indicator light on command, the indicator light starts to flash. When the instrument receives an indicator light off command, the indicator light turns off.

[0051] Preferably, the color of the indicator light during the automatic center calibration process is different from the color of the indicator light during the initial center calibration. As an embodiment, during the initial center calibration, the color of the indicator light is red; during the automatic center calibration, the color of the indicator light is green.

[0052] S160: Calculate the linear coefficients of the second front axle angle signal and the second steering wheel angle signal collected during the calibration process, and use the linear coefficients as calibration coefficients, thereby completing the entire automatic center calibration process.

[0053] Preferably, taking into account that the second front axle angle signal and the second steering wheel angle signal may fluctuate slightly during the calibration process, before calculating the linear coefficient, the mean of the second front axle angle signal and the mean of the second steering wheel angle signal within a preset time length are calculated first, and the linear coefficient is calculated using the two means.

[0054] S170: Sending a sleep instruction for automatic center position calibration to the electric steering gear controller, and the electric steering gear controller does not start the automatic center position calibration function.

[0055] Based on the above, the present application also provides an automatic center position calibration device for a commercial light truck. Figure 2 As shown, the automatic center position calibration device includes a first receiving module 210 , a first calculating module 220 , a first instruction sending module 230 , a second receiving module 240 and a second calculating module 250 .

[0056] The first receiving module 210 is used to receive a first front axle angle signal and a first steering wheel angle signal in real time when the vehicle is in a driving state.

[0057] The first calculation module 220 is used to calculate the error between the first front axle angle signal and the first steering wheel angle signal.

[0058] The first instruction sending module 230 is used to send a wake-up instruction for automatic center position calibration to the electric steering controller when the error is greater than or equal to the angle threshold, so that the electric steering controller responds to the wake-up instruction to keep the vehicle moving in a straight line; when the error is less than the angle threshold, send a sleep instruction for automatic center position calibration to the electric steering controller.

[0059] The second receiving module 240 is used to sequentially receive a calibration start signal and a calibration end signal of the electric steering gear controller.

[0060] The second calculation module 250 is used to calculate the linear coefficients of the second front axle angle signal and the second steering wheel angle signal collected during the calibration process, and use the linear coefficients as calibration coefficients.

[0061] Preferably, the time interval of the calibration process is a preset duration.

[0062] Preferably, the automatic center calibration device for commercial light trucks also includes a second instruction sending module 260, which is used to send an indicator light on instruction to the instrument in response to receiving a calibration start signal, and send an indicator light off instruction to the instrument in response to receiving a calibration end signal.

[0063] Preferably, the first instruction sending module 230 is used to send a sleep instruction for automatic neutral position calibration to the electric steering gear controller when the error is less than the turning angle threshold.

[0064] Preferably, the color of the indicator light during the automatic center calibration process is different from the color of the indicator light during the initial center calibration.

[0065] Preferably, the first instruction sending module 230 is used to send a wake-up instruction for automatic neutral calibration to the electric steering gear controller when the error is greater than or equal to the turning angle threshold and the vehicle speed is greater than the vehicle speed threshold.

[0066] In this application, the vehicle controller automatically determines the conditions for automatic center calibration, and once the conditions are met, the automatic center calibration can be performed, realizing automatic control, completely avoiding the vehicle from running off the track, and greatly improving the driving safety of the vehicle. In addition, in this application, the automatic center calibration is performed during normal vehicle driving, and there is no need to operate the vehicle under specific conditions for the purpose of calibration, which greatly improves the convenience of calibration.

[0067] Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are only for illustration, not for limiting the scope of the present application. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A method for automatic center calibration of a commercial light truck. It is characterized in that Applicable to the vehicle controller, the automatic center position calibration method includes: When the vehicle is in a driving state, receiving a first front axle angle signal and a first steering wheel angle signal in real time; calculating an error between the first front axle angle signal and the first steering wheel angle signal; If the error is greater than or equal to the turning angle threshold, a wake-up instruction for automatic neutral calibration is sent to the electric steering gear controller, so that the electric steering gear controller keeps the vehicle moving in a straight line in response to the wake-up instruction; receiving a calibration start signal and a calibration end signal from an electric steering gear controller in sequence; The linear coefficients of the second front axle angle signal and the second steering wheel angle signal collected during the calibration process are calculated, and the linear coefficients are used as calibration coefficients.

2. The automatic center position calibration method for a commercial light truck according to claim 1, It is characterized in that The calibration process is performed at a preset time interval.

3. The automatic center position calibration method for a commercial light truck according to claim 1 or 2, It is characterized in that Also includes: sending an indicator light on command to the instrument in response to receiving a calibration start signal; In response to receiving the calibration end signal, an indicator light off instruction is sent to the instrument.

4. The automatic center position calibration method for a commercial light truck according to claim 1, It is characterized in that If the error is less than the turning angle threshold, a sleep instruction for automatic center position calibration is sent to the electric steering gear controller.

5. The automatic center position calibration method for a commercial light truck according to claim 3, It is characterized in that The color of the indicator light during automatic center calibration is different from the color of the indicator light during initial center calibration.

6. An automatic center position calibration device for commercial light trucks, It is characterized in that It includes a first receiving module, a first calculating module, a first instruction sending module, a second receiving module and a second calculating module; The first receiving module is used to receive a first front axle angle signal and a first steering wheel angle signal in real time when the vehicle is in a driving state; The first calculation module is used to calculate the error between the first front axle angle signal and the first steering wheel angle signal; The first instruction sending module is used to send a wake-up instruction of automatic neutral calibration to the electric steering gear controller when the error is greater than or equal to the turning angle threshold, so that the electric steering gear controller keeps the vehicle moving in a straight line in response to the wake-up instruction; The second receiving module is used to sequentially receive a calibration start signal and a calibration end signal of the electric steering gear controller; The second calculation module is used to calculate the linear coefficients of the second front axle angle signal and the second steering wheel angle signal collected during the calibration process, and use the linear coefficients as calibration coefficients.

7. The automatic center position calibration device for a commercial light truck according to claim 6, It is characterized in that The calibration process is performed at a preset time interval.

8. The automatic center position calibration device for a commercial light truck according to claim 6, It is characterized in that It also includes a second instruction sending module, which is used to send an indicator light turning on instruction to the instrument in response to receiving a calibration start signal, and send an indicator light turning off instruction to the instrument in response to receiving a calibration end signal.

9. The automatic center position calibration device for a commercial light truck according to claim 6, It is characterized in that The first instruction sending module is used to send a sleep instruction for automatic center position calibration to the electric steering gear controller when the error is less than the turning angle threshold.

10. The automatic center position calibration device for a commercial light truck according to claim 8, It is characterized in that The color of the indicator light during automatic center calibration is different from the color of the indicator light during initial center calibration.

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