Steering wheel differential return method and device of vehicle, vehicle and storage medium

Abstract

The application relates to a steering wheel differential return-to-center method and device of a vehicle, a vehicle and a storage medium, wherein the method comprises the following steps: determining whether a hand torque applied by a driver on a steering wheel is less than a preset threshold value; if the hand torque is less than the preset threshold value and the hand torque meets a preset time condition, it is determined that the driver does not control the steering wheel, and differential control is performed on the steering wheel based on an active disturbance rejection controller (ADRC); and the target differential return-to-center compensation torque is distributed to target wheels of the vehicle to obtain control torque of a hub motor of the target wheel meeting a preset optimal condition. According to the embodiment of the application, the target differential return-to-center compensation torque can be distributed to the target wheels of the vehicle to obtain the control torque of the hub motor of the target wheel meeting the preset certain optimal condition, differential control of the electric wheel independent driving is completed through the active disturbance rejection controller, active return-to-center of the steering wheel after the driver releases the steering wheel is realized, and the return-to-center speed and the control robustness are effectively increased.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to a method, device, vehicle, and storage medium for differential steering wheel return of a vehicle. Background Technology

[0002] In recent years, the number of cars on the road has been increasing, and the automotive industry is currently undergoing a transformation towards the "new four modernizations" trend: electrification, intelligentization, connectivity, and sharing. Under the development trend of electrification, a new power steering concept based on differential power steering for electric wheel drive vehicles has emerged.

[0003] In related technologies, return-to-center control for electric power steering is already very widespread. A common control method is to control the return-to-center by applying a return-to-center compensation current to the basic assist current. This method can calculate the return-to-center current at different vehicle speeds based on the vehicle speed, correct the return-to-center current, and then add the return-to-center current to the electric assist current.

[0004] However, the PID control algorithm in related technologies is essentially linear control. It does not return to center sufficiently at low speeds and is prone to overshoot at high speeds. The controller parameters have poor adaptability and need to be dynamically adjusted according to changes in vehicle speed, which urgently needs to be improved. Summary of the Invention

[0005] This application provides a method, device, vehicle, and storage medium for differential steering wheel return to center in a vehicle, in order to solve the problems in the related art where the PID control algorithm is essentially linear control, which is not sufficient for return to center at low speeds, is prone to overshooting at high speeds, has poor adaptiveness of controller parameters, and needs to be dynamically adjusted according to changes in vehicle speed.

[0006] The first aspect of this application provides a method for differential steering wheel return to center in a vehicle, comprising the following steps: receiving a return signal sent by the steering wheel; responding to the return signal, determining whether the hand torque applied by the driver to the steering wheel is less than a preset threshold; if the hand torque is less than the preset threshold and the hand torque meets a preset time condition, determining that the driver is not controlling the steering wheel, and performing differential control on the steering wheel based on an Active Disturbance Rejection Controller (ADRC) to output a target differential return compensation torque; distributing the target differential return compensation torque to a target wheel of the vehicle to obtain a control torque of the hub motor of the target wheel that meets a preset optimal condition, and using the control torque of the hub motor to perform differential return to center on the steering wheel.

[0007] Based on the above technical means, the target differential return compensation torque can be distributed to the target wheel of the vehicle to obtain the control torque of the hub motor of the target wheel that meets the preset optimal conditions. The independent drive differential control of the electric wheel is completed through the self-disturbance rejection controller, so as to realize the active return of the steering wheel after the driver takes the steering wheel off the wheel, effectively increasing the return speed and control robustness.

[0008] Optionally, in one embodiment of this application, the differential control of the steering wheel based on the Active Disturbance Rejection Controller (ADRC) to output a target differential return compensation torque includes: designing a tracking differentiator, an extended state observer, a nonlinear error feedback control law, and a disturbance estimation compensation for the ADRC to obtain the output result of the ADRC; and generating the target differential return compensation torque based on the output result of the ADRC.

[0009] Based on the above technical means, an ADRC controller can be designed to obtain the output result of the Active Disturbance Rejection Controller (ADRC). The target differential return compensation torque can be generated based on the output result of the ADRC, thereby further realizing the active return of the steering wheel to center after the driver takes the steering wheel out of his hands.

[0010] Optionally, in one embodiment of this application, the disturbance estimation and compensation design for the Active Disturbance Rejection Controller (ADRC) includes: generating a target disturbance based on the environmental disturbances experienced by the steering wheel; estimating and compensating for the target disturbance to obtain the control result of the disturbance estimation and compensation design for the steering wheel.

[0011] Based on the above technical means, the target disturbance can be estimated and compensated, and the final control quantity can be determined by addition and subtraction with the nonlinear error feedback control quantity. This results in the control result of the steering wheel disturbance estimation and compensation design, thereby ensuring that the steering wheel can actively return to center after the driver takes his hands off the steering wheel, effectively increasing the return speed and control robustness.

[0012] Optionally, in one embodiment of this application, the step of distributing the target differential return compensation torque to the target wheel of the vehicle to obtain the control torque of the hub motor of the target wheel that satisfies the preset optimal conditions includes: generating a target function for distributing the target differential return compensation torque to the target wheel of the vehicle based on the target wheel of the vehicle, the tire radius of the vehicle, and the normal load of the target wheel; establishing at least one constraint condition among the differential return compensation torque constraint, the longitudinal force dynamic equation condition, and the longitudinal force maximum condition of the target differential return compensation torque; and obtaining the control torque of the hub motor of the target wheel based on the target function and the at least one constraint condition.

[0013] Based on the aforementioned technical means and the steering wheel return-to-center control principle, differential power steering takes minimizing the steering wheel angle response as the control objective and the return-to-center compensation torque as the control output, thereby actively assisting the steering wheels to return to center quickly, accurately, and stably without increasing the energy consumption of additional hardware systems.

[0014] Optionally, in one embodiment of this application, the differential return of the steering wheel using the control torque of the hub motor includes: generating a drive steering torque for the target wheel based on the output torque of the hub motor; controlling the steering wheel to reach a preset torque condition using the drive steering torque; and returning the steering wheel to center when the preset torque condition is met.

[0015] Based on the above-mentioned technical means, the output torque of the hub motor can be precisely controlled to generate the driving steering torque of the left and right front wheels of the vehicle. The driving steering torque is used to control the steering wheel to reach a certain torque condition, and under a certain torque condition, the steering wheel is straightened, thereby further reducing the steering wheel torque.

[0016] A second aspect of this application provides a differential return-to-center device for a vehicle steering wheel, comprising: a judgment module, configured to receive a return-to-center signal sent by the steering wheel, and in response to the return-to-center signal, determine whether the hand torque applied by the driver to the steering wheel is less than a preset threshold; a control module, configured to determine that the driver is not controlling the steering wheel when the hand torque is less than the preset threshold and the hand torque meets a preset time condition, and to perform differential control on the steering wheel based on an Active Disturbance Rejection Controller (ADRC) to output a target differential return-to-center compensation torque; and a return-to-center module, configured to distribute the target differential return-to-center compensation torque to a target wheel of the vehicle to obtain a control torque of the hub motor of the target wheel that meets a preset optimal condition, and to use the control torque of the hub motor to perform differential return-to-center on the steering wheel.

[0017] Optionally, in one embodiment of this application, the control module includes: a design unit, configured to perform tracking differentiator design, extended state observer design, nonlinear error feedback control law design, and disturbance estimation compensation design on the Active Disturbance Rejection Controller (ADRC) to obtain the output result of the ADRC; and a first generation unit, configured to generate the target differential homing compensation torque based on the output result of the ADRC.

[0018] Optionally, in one embodiment of this application, the design unit includes: a generation subunit, used to generate a target disturbance based on the environmental disturbances experienced by the steering wheel; and a design subunit, used to estimate and compensate for the target disturbance to obtain the control result of the disturbance estimation and compensation design of the steering wheel.

[0019] Optionally, in one embodiment of this application, the return-to-center module includes: a second generation unit, configured to generate a target function for distributing the target differential return-to-center compensation torque to the target wheel of the vehicle based on the target wheel of the vehicle, the tire radius of the vehicle, and the normal load of the target wheel; an establishment unit, configured to establish at least one constraint condition among the differential return-to-center compensation torque constraint, longitudinal force dynamic equation condition, and longitudinal force maximum condition of the target differential return-to-center compensation torque; and a third generation unit, configured to obtain the control torque of the hub motor of the target wheel based on the target function and the at least one constraint condition.

[0020] Optionally, in one embodiment of this application, the return-to-center module further includes: a fourth generation unit, configured to generate the driving steering torque of the target wheel based on the output torque of the hub motor; and a return-to-center unit, configured to use the driving steering torque to control the steering wheel to reach a preset torque condition, and to return the steering wheel to center when the preset torque condition is met.

[0021] A third aspect of this application provides a vehicle, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the vehicle's differential steering wheel return method as described in the above embodiments.

[0022] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described vehicle steering wheel differential return-to-center method.

[0023] This application embodiment can distribute the target differential return-to-center compensation torque to the target wheel of the vehicle, obtaining the control torque of the hub motor of the target wheel that meets the preset optimal conditions. Through an active disturbance rejection controller, independent drive differential control of the electric wheel is completed, enabling the steering wheel to actively return to center after the driver releases their hands, effectively increasing the return-to-center speed and control robustness. This solves the problems in related technologies where the PID control algorithm is essentially linear control, resulting in insufficient return-to-center at low speeds, easy overshoot at high speeds, poor controller parameter adaptability, and the need for dynamic adjustment according to vehicle speed changes.

[0024] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0025] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0026] Figure 1This is a flowchart of a vehicle steering wheel differential return-to-center method according to an embodiment of this application;

[0027] Figure 2 This is a flowchart of a vehicle steering wheel differential return-to-center method according to an embodiment of this application;

[0028] Figure 3 This is a schematic diagram of a vehicle steering wheel differential return device according to an embodiment of this application;

[0029] Figure 4 This is a structural schematic diagram of a vehicle provided according to an embodiment of this application. Detailed Implementation

[0030] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0031] The following description, with reference to the accompanying drawings, outlines a vehicle steering wheel differential return-to-center method, apparatus, vehicle, and storage medium according to embodiments of this application. Addressing the issues raised in the background section regarding the PID control algorithm, which is essentially linear control, resulting in insufficient return-to-center at low speeds, overshooting at high speeds, poor controller parameter adaptability, and the need for dynamic adjustment with vehicle speed, this application provides a vehicle steering wheel differential return-to-center method. In this method, the target differential return-to-center compensation torque is distributed to the target wheel of the vehicle, obtaining the control torque of the hub motor of the target wheel that meets preset optimal conditions. Independent drive differential control of the electric wheel is achieved through an active disturbance rejection controller, enabling active return of the steering wheel after the driver releases their hands, effectively increasing the return-to-center speed and control robustness. This solves the problems of the PID control algorithm in the related art, which is essentially linear control, resulting in insufficient return-to-center at low speeds, overshooting at high speeds, poor controller parameter adaptability, and the need for dynamic adjustment with vehicle speed.

[0032] Specifically, Figure 1 This is a flowchart illustrating a method for differential steering wheel return to center in a vehicle, as provided in an embodiment of this application.

[0033] like Figure 1 As shown, the differential steering wheel return method for this vehicle includes the following steps:

[0034] In step S101, a return-to-center signal sent by the steering wheel is received, and in response to the return-to-center signal, it is determined whether the hand torque applied by the driver on the steering wheel is less than a preset threshold.

[0035] It is understood that the centering signal in the embodiments of this application can be obtained from the steering wheel torque sensor, wherein the centering signal can be the steering wheel torque sensor signal.

[0036] In actual implementation, the embodiments of this application can obtain the return-to-center signal from the steering wheel torque sensor through the electric power steering system EPS (Electric Power Steering). Based on the return-to-center signal, it can determine whether the driver is operating the steering wheel and detect whether the hand torque applied by the driver to the steering wheel is less than a certain threshold, thereby providing support for the subsequent return-to-center control of the steering wheel. This ensures that the actively assisted steering wheels can return to center quickly, accurately and stably without increasing the energy consumption of the additional hardware system.

[0037] It should be noted that the preset threshold can be set by those skilled in the art according to the actual situation, and no specific restrictions are imposed here.

[0038] In step S102, if the hand torque is less than a preset threshold and the hand torque meets the preset time condition, it is determined that the driver is not controlling the steering wheel, and differential control of the steering wheel is performed based on the Active Disturbance Rejection Controller (ADRC) to output the target differential return compensation torque.

[0039] It is understood that the preset threshold in the embodiments of this application can be a given threshold obtained according to the driver's instructions; the preset time condition can be the torque applied by the driver on the steering wheel for a certain period of time; ADRC can show significant advantages in harsh environments with severe disturbances and in situations where high-precision control is required. It treats all uncertainties of the controlled object as unknown disturbances and estimates and compensates for the disturbances through the input of the controlled object, thereby obtaining a more suitable control quantity. This disturbance compensation does not require direct measurement of the disturbance, nor does it require knowledge of the law of the disturbance's effect on the controlled object.

[0040] In actual implementation, this embodiment can determine that the driver is not operating the steering wheel after detecting that the hand torque applied by the driver to the steering wheel is less than a given threshold and remains so for a period of time, thereby providing support for subsequent steering wheel return control. This embodiment can perform differential control of the steering wheel based on the Active Disturbance Rejection Controller (ADRC) to output a target differential return compensation torque.

[0041] For example, in this embodiment of the application, the hand torque threshold can be 0.4 Nm and the duration threshold can be 2 s. When the hand torque applied by the driver to the steering wheel is 0.1 Nm and lasts for 2 s, it is determined that the driver is not operating the steering wheel. At this time, differential control of the steering wheel can be performed based on the active disturbance rejection controller (ADRC) to provide a basis for the steering wheel to return to center.

[0042] In this embodiment, the independent drive differential control of the electric wheel is completed through the Active Disturbance Rejection Controller (ADRC), which enables the steering wheel to actively return to center after the driver takes his hands off the steering wheel, effectively increasing the return speed and control robustness.

[0043] It should be noted that the preset threshold and preset time conditions can be set by those skilled in the art according to the actual situation, and no specific restrictions are imposed here.

[0044] Optionally, in one embodiment of this application, differential control of the steering wheel is performed based on the Active Disturbance Rejection Controller (ADRC) to output a target differential return compensation torque, including: designing a tracking differentiator, an extended state observer, a nonlinear error feedback control law, and a disturbance estimation compensation for the ADRC to obtain the output result of the ADRC; and generating the target differential return compensation torque based on the output result of the ADRC.

[0045] It is understood that the target differential return compensation torque in the embodiments of this application can be designed using an ADRC controller.

[0046] Specifically, embodiments of this application can be used to design a tracking differentiator:

[0047] For nonlinear systems, a tracking differentiator as shown in the following equation is used:

[0048]

[0049] Where x1 and x2 are state variables, and R is a velocity factor, where a larger R indicates a faster tracking speed. Let h be the target steering wheel angle and h be the tracking step size, representing an optimal choice. It can be set to 0.

[0050] The design of the fhan function is shown in formula (2):

[0051]

[0052] Furthermore, embodiments of this application can be used to design an extended state observer, employing formula (3) as the extended state observer:

[0053]

[0054] Where α1 and α2 are nonlinear factors in the fal function, z1 is the target value of the tracking steering wheel angle, z2 is the actual value of the tracking steering wheel angle, z3 is the extended state variable including external disturbances, and T * For the target differential torque, the design of the fal function is shown in formula (4):

[0055]

[0056] Where φ is the length of the linear interval, and e is the error, calculated using formula (5):

[0057]

[0058] Furthermore, embodiments of this application can be used to design nonlinear error feedback control laws:

[0059]

[0060] Where e1 is the steering wheel angle error term, e2 is the steering wheel angle change rate error term; γ1 and γ2 are the combination coefficients of the nonlinear function, and u0 is the control output of the nonlinear error feedback control law.

[0061] Furthermore, the embodiments of this application can be designed with a disturbance estimation and compensation module, as shown in formula (7):

[0062]

[0063] Therefore, the output of the entire ADRC controller is the target differential homing compensation torque ΔT. * .

[0064] The embodiments of this application can adopt an ADRC controller design to obtain the output result of the Active Disturbance Rejection Controller (ADRC). Based on the output result of the ADRC, a target differential return-to-center compensation torque is generated, thereby further realizing the active return of the steering wheel after the driver takes the steering wheel off the wheel, effectively increasing the return-to-center speed and control robustness.

[0065] Optionally, in one embodiment of this application, the disturbance estimation and compensation design for the Active Disturbance Rejection Controller (ADRC) includes: generating a target disturbance based on the environmental disturbances experienced by the steering wheel; estimating and compensating for the target disturbance to obtain the control result of the disturbance estimation and compensation design for the steering wheel.

[0066] It is understood that, in the embodiments of this application, since the extended state variables estimate the disturbances of the external environment to which the system is subjected, the role of disturbance estimation compensation is to compensate for this tracking disturbance term.

[0067] Therefore, in this embodiment, a target disturbance can be generated based on the environmental disturbances experienced by the steering wheel. The target disturbance can be the aforementioned tracking disturbance term. The tracking disturbance term is estimated and compensated, and the final control quantity is determined by addition and subtraction with the nonlinear error feedback control quantity. This results in the control result of the steering wheel disturbance estimation and compensation design, thereby ensuring that the steering wheel actively returns to center after the driver releases his hands, effectively increasing the return speed and control robustness.

[0068] In step S103, the target differential return compensation torque is distributed to the target wheel of the vehicle to obtain the control torque of the hub motor of the target wheel that meets the preset optimal conditions, and the control torque of the hub motor is used to perform differential return of the steering wheel.

[0069] It is understood that the target wheel in this application embodiment can be the two front wheels of the vehicle; the preset optimal condition can be the condition that satisfies the optimal allocation; the steering wheel return performance can be: the steering wheel's response ability to return to the center position when the driver makes a slight adjustment to the steering at a relatively low speed or releases the steering wheel in time after turning normally, and the return ability is also an important indicator for evaluating steering feel.

[0070] In actual implementation, the embodiments of this application can optimally distribute the target differential return compensation torque to the target wheels of the vehicle to obtain the optimal control torque of the hub motors of the two front wheels that meet certain preset conditions, and use the optimal control torque to perform differential return of the steering wheel, thereby achieving the purpose of reducing the steering wheel torque.

[0071] It should be noted that the preset optimal conditions can be set by those skilled in the art according to the actual situation, and no specific restrictions are imposed here.

[0072] Optionally, in one embodiment of this application, the distribution of the target differential return compensation torque to the target wheel of the vehicle to obtain the control torque of the hub motor of the target wheel that satisfies the preset optimal conditions includes: generating an objective function for distributing the target differential return compensation torque to the target wheel of the vehicle based on the target wheel of the vehicle, the tire radius of the vehicle, and the normal load of the target wheel; establishing at least one constraint condition among the differential return compensation torque constraint, the longitudinal force dynamic equation condition, and the longitudinal force maximum condition of the target differential return compensation torque; and obtaining the control torque of the hub motor of the target wheel based on the objective function and at least one constraint condition.

[0073] Understandably, torque is an important parameter for measuring the output torque of the wheel hub motor in an electric vehicle.

[0074] As one possible implementation method, embodiments of this application can be based on the left front wheel, right front wheel, and tire radius R of the vehicle. w and the normal load F of the wheel zi The objective function generates the target differential return compensation torque and distributes it to the target wheels of the vehicle.

[0075] Using road surface adhesion utilization rate as the objective function, the lower the road surface adhesion utilization rate, the lower the vehicle's driving stability and the lower the possibility of sideslip. The formula is as follows:

[0076]

[0077] In this context, the subscripts 1 and 2 represent the left front wheel and the right front wheel, respectively, and R w F is the tire radius. zi The normal load of the wheel is estimated as shown in formula (9):

[0078]

[0079] Among them, H g B is the height of the center of gravity, and B is the wheelbase. v is the longitudinal velocity of the car, and v is the lateral velocity of the car.

[0080] The motor output torque and the longitudinal force on the wheel have the following relationship:

[0081] T i =F xi R w ,i=1,2(10)

[0082] Furthermore, in order to solve the optimization problem in this application, the following constraints are established:

[0083] Condition 1: Differential return compensation torque constraint:

[0084]

[0085] Condition 2: Longitudinal force dynamics equation conditions:

[0086]

[0087] Condition 3: Maximum longitudinal force condition:

[0088]

[0089] Among them, T i_max This represents the maximum output torque of the motor.

[0090] In this embodiment, formulas (11) and (12) can be substituted into the objective function formula (8), and the conditional extrema can be obtained using the Lagrange multiplier method, as shown in formula (14). The torque T of each wheel can then be calculated. i :

[0091]

[0092] In this embodiment, based on the steering wheel return-to-center control principle, differential power steering can take minimizing the steering wheel angle response as the control objective and the return-to-center compensation torque as the control output, thereby actively assisting the steering wheels to return to center quickly, accurately and stably without increasing the energy consumption of additional hardware systems.

[0093] Optionally, in one embodiment of this application, differential return of the steering wheel using the control torque of the hub motor includes: generating a drive steering torque for the target wheel based on the output torque of the hub motor; controlling the steering wheel to reach a preset torque condition using the drive steering torque; and returning the steering wheel to center when the preset torque condition is met.

[0094] It is understood that the target wheel in this application embodiment can be the left or right front wheel of the vehicle; the preset torque condition in this application embodiment can be the condition that satisfies the steering wheel torque.

[0095] In actual implementation, the embodiments of this application can generate driving steering torque for the left and right front wheels of the vehicle by precisely controlling the output torque of the hub motor. The driving steering torque is used to control the steering wheel to reach a certain torque condition, and under the condition of a certain torque, the steering wheel is straightened, thereby further reducing the steering wheel torque.

[0096] For example, in this embodiment of the application, when the output torque of the hub motor is 800 N*m, the driving steering torque of the left and right front wheels of the vehicle is 40 N. The driving steering torque is used to control the steering wheel to reach a certain torque condition, and under the condition of a certain torque, the steering wheel is straightened.

[0097] It should be noted that the preset torque conditions can be set by those skilled in the art according to the actual situation, and no specific restrictions are imposed here.

[0098] Specifically, it can be combined with Figure 2 As shown, the working principle of the vehicle steering wheel differential return method in this application embodiment is explained in detail with a specific example.

[0099] like Figure 2 As shown, embodiments of this application may include the following steps:

[0100] Step S201: The EPS determines whether the driver is operating the steering wheel based on the steering wheel torque sensor signal. When it detects that the hand torque applied to the steering wheel is less than a given threshold and continues for a period of time, it determines that the driver is not operating the steering wheel and activates the steering wheel return control.

[0101] Step S202: Perform homing control according to the ADRC controller and output the target homing torque.

[0102] Step S203: Optimize the distribution of the target return torque to the two front wheels to obtain the optimal control torque of the two front wheel hub motors.

[0103] According to the vehicle steering wheel differential return-to-center method proposed in this application, the target differential return-to-center compensation torque can be distributed to the target wheel of the vehicle to obtain the control torque of the hub motor of the target wheel that meets the preset optimal conditions. The independent drive differential control of the electric wheel is completed through an active disturbance rejection controller, enabling the steering wheel to actively return to center after the driver releases their hands, effectively increasing the return-to-center speed and control robustness. This solves the problem in related technologies where the PID control algorithm is essentially linear control, resulting in insufficient return-to-center at low speeds, easy overshoot at high speeds, poor controller parameter adaptability, and the need for dynamic adjustment according to vehicle speed.

[0104] Next, referring to the accompanying drawings, a differential steering wheel return device for a vehicle according to an embodiment of this application is described.

[0105] Figure 3 This is a schematic diagram of the differential return device of the vehicle steering wheel according to an embodiment of this application.

[0106] like Figure 3 As shown, the vehicle's steering wheel differential return device 10 includes: a judgment module 100, a control module 200, and a return module 300.

[0107] Specifically, the judgment module 100 is used to receive the return-to-center signal sent by the steering wheel, and in response to the return-to-center signal, to determine whether the hand torque applied by the driver on the steering wheel is less than a preset threshold.

[0108] The control module 200 is used to determine that the driver is not controlling the steering wheel when the hand torque is less than a preset threshold and the hand torque meets a preset time condition, and to perform differential control of the steering wheel based on the active disturbance rejection controller (ADRC) to output the target differential return compensation torque.

[0109] The return module 300 is used to distribute the target differential return compensation torque to the target wheel of the vehicle, obtain the control torque of the hub motor of the target wheel that meets the preset optimal conditions, and use the control torque of the hub motor to perform differential return of the steering wheel.

[0110] Optionally, in one embodiment of this application, the control module 200 includes a design unit and a first generation unit.

[0111] The design unit is used to design the tracking differentiator, the extended state observer, the nonlinear error feedback control law, and the disturbance estimation and compensation for the Active Disturbance Rejection Controller (ADRC), and to obtain the output results of the ADRC.

[0112] The first generation unit is used to generate the target differential homing compensation torque based on the output of the Active Disturbance Rejection Controller (ADRC).

[0113] Optionally, in one embodiment of this application, the design unit includes: a generation subunit and a design subunit.

[0114] The generation subunit is used to generate target disturbances based on the environmental disturbances experienced by the steering wheel.

[0115] Design sub-units are used to estimate and compensate for target disturbances, and obtain the control results of the steering wheel disturbance estimation and compensation design.

[0116] Optionally, in one embodiment of this application, the alignment module 300 includes: a second generation unit, an establishment unit, and a third generation unit.

[0117] The second generation unit is used to generate a target function for distributing the target differential return compensation torque to the target wheel of the vehicle based on the target wheel of the vehicle, the tire radius of the vehicle, and the normal load of the target wheel.

[0118] Establish a unit to establish at least one of the following constraints for the target differential return compensation torque: differential return compensation torque constraint, longitudinal force dynamic equation condition, and longitudinal force maximum condition.

[0119] The third generation unit is used to obtain the control torque of the hub motor of the target wheel according to the objective function and at least one constraint condition.

[0120] Optionally, in one embodiment of this application, the alignment module 300 further includes a fourth generation unit and an alignment unit.

[0121] The fourth generation unit is used to generate the drive steering torque of the target wheel based on the output torque of the hub motor.

[0122] The return-to-center unit is used to control the steering wheel to reach a preset torque condition using the driving steering torque, and to return the steering wheel to center when the preset torque condition is met.

[0123] It should be noted that the foregoing explanation of the embodiment of the vehicle's differential steering wheel return method also applies to the vehicle's differential steering wheel return device in this embodiment, and will not be repeated here.

[0124] The vehicle steering wheel differential return device proposed in this application can distribute the target differential return compensation torque to the target wheel of the vehicle, obtaining the control torque of the hub motor of the target wheel that meets the preset optimal conditions. Through an active disturbance rejection controller, independent drive differential control of the electric wheel is completed, enabling the steering wheel to actively return to center after the driver releases their hands, effectively increasing the return speed and control robustness. This solves the problem in related technologies where the PID control algorithm is essentially linear control, resulting in insufficient return at low speeds, easy overshoot at high speeds, poor controller parameter adaptability, and the need for dynamic adjustment according to vehicle speed.

[0125] Figure 4 A schematic diagram of the structure of a vehicle provided in an embodiment of this application. The vehicle may include:

[0126] The memory 401, the processor 402, and the computer program stored on the memory 401 and capable of running on the processor 402.

[0127] When the processor 402 executes the program, it implements the vehicle steering wheel differential return method provided in the above embodiments.

[0128] Furthermore, the vehicle also includes:

[0129] Communication interface 403 is used for communication between memory 401 and processor 402.

[0130] The memory 401 is used to store computer programs that can run on the processor 402.

[0131] The memory 401 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0132] If the memory 401, processor 402, and communication interface 403 are implemented independently, then the communication interface 403, memory 401, and processor 402 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be divided into address buses, data buses, control buses, etc. For ease of representation, Figure 4 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0133] Optionally, in a specific implementation, if the memory 401, processor 402, and communication interface 403 are integrated on a single chip, then the memory 401, processor 402, and communication interface 403 can communicate with each other through an internal interface.

[0134] Processor 402 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0135] This embodiment also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described vehicle steering wheel differential return-to-center method.

[0136] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0137] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0138] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0139] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0140] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0141] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0142] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0143] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A method for differential return of a vehicle's steering wheel, characterized in that, Includes the following steps: Receive a return-to-center signal from the steering wheel, and in response to the return-to-center signal, determine whether the hand torque applied by the driver to the steering wheel is less than a preset threshold. If the hand torque is less than the preset threshold and the hand torque meets the preset time condition, it is determined that the driver is not controlling the steering wheel, and differential control of the steering wheel is performed based on the Active Disturbance Rejection Controller (ADRC) to output the target differential return compensation torque. The target differential return compensation torque is distributed to the target wheel of the vehicle to obtain the control torque of the hub motor of the target wheel that meets the preset optimal conditions, and the control torque of the hub motor is used to perform differential return of the steering wheel.

2. The method according to claim 1, characterized in that, The differential control of the steering wheel based on the Active Disturbance Rejection Controller (ADRC) to output a target differential return-to-center compensation torque includes: The active disturbance rejection controller (ADRC) is designed by performing a tracking differentiator, an extended state observer, a nonlinear error feedback control law, and a disturbance estimation compensation design, respectively, and the output result of the ADRC is obtained. The target differential return compensation torque is generated based on the output of the Active Disturbance Rejection Controller (ADRC).

3. The method according to claim 2, characterized in that, The disturbance estimation and compensation design for the Active Disturbance Rejection Controller (ADRC) includes: Target disturbance is generated based on the environmental disturbances experienced by the steering wheel; The target disturbance is estimated and compensated to obtain the control result of the disturbance estimation and compensation design of the steering wheel.

4. The method according to claim 1, characterized in that, The step of distributing the target differential return compensation torque to the target wheel of the vehicle to obtain the control torque of the hub motor of the target wheel that satisfies the preset optimal conditions includes: Based on the target wheel of the vehicle, the tire radius of the vehicle, and the normal load of the target wheel, a target function is generated to distribute the target differential return compensation torque to the target wheel of the vehicle. Establish at least one of the following constraints for the target differential return compensation torque: differential return compensation torque constraint, longitudinal force dynamic equation condition, and longitudinal force maximum condition; The control torque of the hub motor of the target wheel is obtained based on the objective function and the at least one constraint condition.

5. The method according to claim 1, characterized in that, The differential return of the steering wheel using the control torque of the hub motor includes: The drive steering torque of the target wheel is generated based on the output torque of the hub motor; The steering wheel is controlled to reach a preset torque condition using the driving steering torque, and the steering wheel is returned to center when the preset torque condition is met.

6. A differential return-to-center device for a vehicle steering wheel, characterized in that, include: The judgment module is used to receive the return-to-center signal sent by the steering wheel, and in response to the return-to-center signal, to determine whether the hand torque applied by the driver on the steering wheel is less than a preset threshold. The control module is used to determine that the driver is not controlling the steering wheel when the hand torque is less than the preset threshold and the hand torque meets the preset time condition, and to perform differential control on the steering wheel based on the active disturbance rejection controller (ADRC) to output the target differential return compensation torque. The return-to-center module is used to distribute the target differential return-to-center compensation torque to the target wheel of the vehicle, obtain the control torque of the hub motor of the target wheel that meets the preset optimal conditions, and use the control torque of the hub motor to perform differential return-to-center of the steering wheel.

7. The apparatus according to claim 6, characterized in that, The control module includes: The design unit is used to design the tracking differentiator, the extended state observer, the nonlinear error feedback control law, and the disturbance estimation compensation for the active disturbance rejection controller (ADRC), and to obtain the output result of the ADRC. The generation unit is used to generate the target differential homing compensation torque based on the output of the Active Disturbance Rejection Controller (ADRC).

8. The apparatus according to claim 7, characterized in that, The design unit includes: A generation subunit is used to generate a target disturbance based on the environmental disturbances experienced by the steering wheel; The design subunit is used to estimate and compensate for the target disturbance, and obtain the control result of the disturbance estimation and compensation design of the steering wheel.

9. A vehicle, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the vehicle steering wheel differential return method as described in any one of claims 1-5.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the vehicle steering wheel differential return method as described in any one of claims 1-5.

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