Active return control method and active return control apparatus

Abstract

The present invention relates to an active return control method and an active return control apparatus. The active return control method comprises: collecting a steering wheel angle and an actual hand torque; on the basis of the steering wheel angle and the actual hand torque, acquiring a maximum hand torque of the steering wheel while moving away from a center position; comparing the actual hand torque with the maximum hand torque to acquire a return torque coefficient; and on the basis of the return torque coefficient and a calculated return control torque, obtaining a final return torque, so as to control active return of the steering wheel. The release intention of a driver is determined according to the trend of change in hand torque, rather than being determined according to the absolute value of the hand torque, thus reducing misjudgments in respect of the release intention of the driver, increasing return response speed, preventing differences in a vehicle steering system on the left and right, and improving robustness.

Description

Active return-to-center control method and active return-to-center control device Technical Field

[0001] This invention relates to the field of vehicle steering control technology. Specifically, this invention relates to an active self-centering control method and an active self-centering control device. Background Technology

[0002] Electro-hydraulic power steering (EHPS) has advantages such as speed-sensitive power assistance, energy saving and environmental protection, and simple structure. It can ensure accurate execution of the driver's steering operation and achieve sensitive and precise vehicle steering. Active return-to-center control of the steering gear is an important function in EHPS control.

[0003] In the active return-to-center control of the steering system, the return-to-center torque coefficient is used as a multiplier factor in the final return-to-center torque calculation. In related technologies, this return-to-center torque coefficient is inversely proportional to the hand torque; the smaller the hand torque, the larger the return-to-center torque coefficient; the larger the hand torque, the smaller the return-to-center torque coefficient.

[0004] However, because the hand torque sensor itself has residual torque, and the residual friction torque of the steering system is also superimposed on the hand torque sensor, a large residual torque is generated. In this situation, it is impossible to accurately determine whether the driver has released the steering wheel, thus sometimes failing to produce a timely and normal return to center.

[0005] Furthermore, the differences between the left and right steering systems of a vehicle lead to asymmetric residual torque. Using a single return torque coefficient cannot adequately address the return performance on both sides. Related technical solutions increase the complexity of the algorithm and the difficulty of calibration, or may fail to guarantee good return function on both sides.

[0006] Summary of the Invention

[0007] To solve the above technical problems, the present invention provides an active return-to-center control method and an active return-to-center control device.

[0008] In a first aspect, embodiments of the present invention provide an active homing control method, the method comprising:

[0009] Collect steering wheel angle and actual hand torque;

[0010] The maximum hand torque is obtained by measuring the steering wheel angle and the actual hand torque as the steering wheel moves away from the center position.

[0011] The return torque coefficient is obtained by comparing the actual hand torque with the maximum hand torque; and

[0012] Based on the return torque coefficient and the return control calculated torque, the final return torque is obtained to control the steering wheel to actively return to center.

[0013] According to some embodiments of the present invention, the step of comparing the actual hand torque with the maximum hand torque to obtain the return torque coefficient includes: the larger the difference between the actual hand torque and the maximum hand torque, the larger the return torque coefficient; the smaller the difference between the actual hand torque and the maximum hand torque, the smaller the return torque coefficient.

[0014] According to some embodiments of the present invention, the self-centering control calculation torque is obtained based on the steering wheel angle, vehicle speed, and proportional-integral-derivative control algorithm.

[0015] According to some embodiments of the present invention, when the return-to-center process is stopped or completed, the maximum hand torque during the process of moving the steering wheel away from the center position is reset to zero.

[0016] According to some embodiments of the present invention, the method determines whether the return-to-center process is interrupted based on the steering wheel angular velocity and the steering wheel turning direction, and determines whether the return-to-center process is completed based on the steering wheel turning angle.

[0017] According to some embodiments of the present invention, when the direction of the steering wheel angular velocity is opposite to the direction of the steering wheel angle, it is determined that the return-to-center process has not been interrupted; when the direction of the steering wheel angular velocity is not opposite to the direction of the steering wheel angle, it is determined that the return-to-center process has been interrupted; when the steering wheel angle is zero, it is determined that the return-to-center process has been completed; when the steering wheel angle is not zero, it is determined that the return-to-center process has not been completed.

[0018] According to some embodiments of the present invention, the step of obtaining the maximum hand torque during the process of the steering wheel moving away from the center position based on the steering wheel angle and the actual hand torque includes: performing low-pass filtering on the data of the steering wheel angle and the actual hand torque.

[0019] In a second aspect, embodiments of the present invention provide an active return-to-center control device, comprising: a data acquisition module for acquiring the steering wheel angle and actual hand torque; a judgment module for acquiring the maximum hand torque during the steering wheel's movement away from the center position based on the steering wheel angle and the actual hand torque; and a calculation module for comparing the actual hand torque with the maximum hand torque to acquire a return-to-center torque coefficient, and obtaining a final return-to-center torque based on the return-to-center torque coefficient and the return-to-center control calculated torque, so as to control the steering wheel to actively return to center.

[0020] According to some embodiments of the present invention, the calculation module is configured to obtain the return torque coefficient based on the difference between the actual hand torque and the maximum hand torque; the larger the difference between the actual hand torque and the maximum hand torque, the larger the return torque coefficient; the smaller the difference between the actual hand torque and the maximum hand torque, the smaller the return torque coefficient.

[0021] According to some embodiments of the present invention, the data acquisition module includes a steering wheel angle sensor, a speed sensor, and a hand torque sensor.

[0022] According to some embodiments of the present invention, the steering wheel angle sensor is used to acquire the steering wheel angle, and the speed sensor is used to acquire the vehicle speed; the calculation module is configured to obtain the return-to-center control calculation torque based on the steering wheel angle, vehicle speed, and proportional-integral-derivative control algorithm.

[0023] According to some embodiments of the present invention, when the return-to-center process is stopped or completed, the determination module is configured to reset the maximum hand torque during the process of moving the steering wheel away from the center position to zero.

[0024] According to some embodiments of the present invention, the judgment module is configured to determine whether the return-to-center process is interrupted based on the steering wheel angular velocity and the steering wheel turning direction, and to determine whether the return-to-center process is completed based on the steering wheel turning angle.

[0025] According to some embodiments of the present invention, the judgment module is configured to: determine that the centering process has not been interrupted when the direction of the steering wheel angular velocity is opposite to the direction of the steering wheel angle; determine that the centering process has been interrupted when the direction of the steering wheel angular velocity is not opposite to the direction of the steering wheel angle; determine that the centering process has been completed when the steering wheel angle is zero; and determine that the centering process has not been completed when the steering wheel angle is not zero.

[0026] Judging the driver's intention to release the handle by the trend of the change in hand torque, rather than by the absolute value of the hand torque, can reduce misjudgment of the driver's intention to release the handle and improve the response speed of returning to center.

[0027] The residual torque of steering systems varies across different vehicles. Calibrating the return torque coefficient using the absolute value of the hand torque would not provide a unified parameter, increasing the difficulty of calibration. However, by judging the driver's intention to release the steering wheel based on the trend of hand torque changes, different residual torques can be covered, increasing the robustness of the active return control device and simplifying the calibration process.

[0028] Furthermore, the left and right symmetry of the steering system of the same vehicle also differs, resulting in inconsistent residual torque on the left and right sides. By judging the driver's intention to release the steering wheel by the trend of the change in hand torque, the problem of left and right symmetry cannot be taken into account when using a set of return torque coefficients in related technologies can be solved. Thus, the difference between the left and right sides is avoided and the robustness is improved. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 shows a flowchart of an active homing control method according to an embodiment of the present invention;

[0031] Figure 2 shows a schematic diagram of the active homing control method according to an embodiment of the present invention;

[0032] Figure 3 shows a flowchart of an active alignment control method for pausing or completing the alignment process according to an embodiment of the present invention; and

[0033] Figure 4 shows a structural block diagram of an active homing control device according to an embodiment of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the described embodiments of this invention are within the scope of protection of this invention.

[0035] This invention relates to the field of vehicle steering control technology. Specifically, this invention relates to an active self-centering control method and an active self-centering control device.

[0036] The active self-centering function of a vehicle steering system relies on the hand torque collected by a hand torque sensor to determine whether the driver intends to center the steering wheel. The smaller the steering hand torque, the stronger the driver's intention to center, and the greater the self-centering torque. Conversely, the greater the steering hand torque, the weaker the driver's intention to center, and the smaller the self-centering torque. A method needs to be designed to calculate the self-centering torque coefficient and obtain the final self-centering torque.

[0037] Figure 1 shows a flowchart of the active self-alignment control method according to an embodiment of the present invention; Figure 2 shows a schematic diagram of the active self-alignment control method according to an embodiment of the present invention. Referring to Figures 1 and 2, the active self-alignment control method provided by the present invention includes:

[0038] Collect steering wheel angle and actual hand torque;

[0039] The maximum hand torque is obtained by measuring the steering wheel angle and the actual hand torque as the steering wheel moves away from the center position.

[0040] The return torque coefficient is obtained by comparing the actual hand torque with the maximum hand torque; and

[0041] Based on the return torque coefficient and the return control calculated torque, the final return torque is obtained to control the steering wheel to actively return to center.

[0042] Specifically, steering wheel angle data can be collected using a steering wheel angle sensor, and actual hand torque data can be collected using a hand torque sensor. The actual hand torque refers to the real-time torque applied by the driver as the steering wheel moves away from the center position; at this time, the direction of the actual hand torque is consistent with the steering wheel angle direction. By comparing the actual hand torque with the maximum hand torque, the return-to-center torque coefficient can be obtained, which characterizes the driver's intention to release the steering wheel. The final return-to-center torque can be calculated by multiplying the return-to-center torque coefficient by the calculated return-to-center control torque.

[0043] It should be understood that the steering wheel turning process can include the process of the steering wheel moving away from the center position and the process of returning to the center position. During the process of the steering wheel moving away from the center position, if the steering wheel angle is not 0 and the steering wheel angular velocity is 0 (i.e., the steering wheel maintains a certain steering angle without change), this is still considered to be within the same process of the steering wheel moving away from the center position. If the steering wheel continues to turn away from the center position subsequently, the maximum hand torque during this process of the steering wheel moving away from the center position will continue to be recorded. The process of the steering wheel moving away from the center position is considered to have ended only when the steering wheel turns towards the center position, that is, the direction of the steering wheel angular velocity is opposite to the direction of the steering wheel angle, at which point the process of the steering wheel moving away from the center position is considered to be in the process of returning to the center position.

[0044] Furthermore, obtaining the maximum hand torque during the process of the steering wheel moving away from the center position based on the steering wheel angle and actual hand torque means obtaining the maximum value among multiple actual hand torque data during the process of the steering wheel moving away from the center position, i.e., the maximum hand torque. Specifically, the magnitude of the hand torque applied by the driver to the steering wheel will change at any time. During a process of the steering wheel moving away from the center position, the difference between the actual hand torque and the maximum hand torque is compared, that is, the current hand torque value is compared with the maximum value of the hand torque recorded during this process of the steering wheel moving away from the center position.

[0045] The return torque coefficient is obtained by comparing the difference between the actual hand torque and the maximum hand torque. Specifically, the larger the difference between the actual hand torque and the maximum hand torque, the greater the driver's intention to let go, the greater the required return torque, and the greater the return torque coefficient. Conversely, the smaller the difference between the actual hand torque and the maximum hand torque, the less the driver's intention to let go, the smaller the required return torque, and the smaller the return torque coefficient.

[0046] Referring to Figure 2, in the interpolation curve of the return torque coefficient, the horizontal axis can be understood as the difference between the actual hand torque and the maximum hand torque, and the vertical axis can be understood as the return torque coefficient. The value range of the return torque coefficient is [0, 1].

[0047] Referring to Figure 2, it can be understood that as the steering torque applied by the driver continuously increases, that is, the current actual torque is the maximum torque applied during the process of the steering wheel moving away from the center position, the difference between the actual torque and the maximum torque is minimized, i.e., 0. At this time, the driver's steering intention is at its maximum, while the driver's intention to release the steering wheel is at its minimum, and the return torque coefficient is at its minimum, approaching 0.

[0048] When the driver reduces the steering torque applied, the current actual torque is no longer the maximum torque. Therefore, there is a difference between the actual torque and the previously recorded maximum torque. A decrease in actual torque means a decrease in the driver's steering intention. The larger the difference between the actual torque and the maximum torque, the greater the driver's intention to release the steering wheel, and the larger the return torque coefficient. The difference between the actual torque and the maximum torque reaches its maximum during the process of the steering wheel moving away from the center position, until the driver releases the steering wheel. At this point, the return torque coefficient is at its maximum, approaching 1.

[0049] Judging the driver's intention to release the steering wheel by the difference between the actual and maximum steering torque—that is, by the trend of the torque change—is clearly more reasonable than judging the driver's intention to release the steering wheel by the absolute value of the torque. The magnitude of the absolute value of the torque cannot accurately represent the driver's intention to release the steering wheel to a certain extent; for example, a large steering torque collected from the sensor does not necessarily mean that the driver does not need the return torque. It may be a misjudgment caused by excessive residual torque, ultimately leading to a misinterpretation of the driver's intention to release the steering wheel, reducing the vehicle's operability and the driver's feel for the vehicle. Judging the driver's intention to release the steering wheel by the difference between the actual and maximum steering torque, and by the trend of the torque change, can reasonably and accurately judge the driver's operating intention, thus providing an appropriate final return torque. At the same time, it ensures that different residual torques can be covered, increasing the robustness of the active return control device and simplifying the calibration work.

[0050] Furthermore, the calculated torque for the return-to-center control can be obtained based on the steering wheel angle, vehicle speed, and proportional-integral-derivative (PID) control algorithm. Specifically, the return-to-center torque can be determined based on the steering wheel angle, vehicle speed, and PID control algorithm. Further, a correction coefficient can be determined based on the steering wheel rotation speed and the actual hand torque applied to the steering wheel; the return-to-center torque is then corrected based on this correction coefficient, and the calculated torque for the return-to-center control is obtained from the corrected return-to-center torque.

[0051] Figure 3 shows a flowchart of an active return-to-center control method when the return-to-center process is stopped or completed according to an embodiment of the present invention. It should be understood that the return-to-center process refers to the process of the steering wheel turning from a certain steering angle toward the center position. In some embodiments, referring to Figure 3, when the return-to-center process is stopped or completed, the maximum hand torque during the steering wheel moving away from the center position is reset to zero. The maximum hand torque during the next steering wheel moving away from the center position process is re-recorded.

[0052] One aspect is that whether the return-to-center process has stopped can be determined based on the steering wheel angular velocity and the steering wheel turning direction. When the direction of the steering wheel angular velocity is opposite to the direction of the steering wheel turning direction, it is considered that the steering wheel is turning from a certain steering angle toward the center position, and the steering wheel is in the process of returning to center.

[0053] When the direction of the steering wheel angular velocity is not opposite to the direction of the steering wheel angle, the return-to-center process is stopped. At this time, the maximum hand torque during the process of the steering wheel moving away from the center position is reset to zero. The maximum hand torque is then recorded again during the process of the steering wheel moving away from the center position, and the active return-to-center control method described above is executed. It should be understood that the above-mentioned direction of the steering wheel angular velocity not being opposite to the direction of the steering wheel angle includes the case where the direction of the steering wheel angular velocity is the same as the direction of the steering wheel angle, and the case where the steering wheel angle is not 0, but the steering wheel angular velocity changes from the opposite direction to 0.

[0054] On the other hand, the completion of the return-to-center process is determined by the steering wheel angle. Specifically, the return-to-center process is considered complete when the steering wheel angle is 0. It should be understood that completion of the return-to-center process includes the case where the steering wheel angular velocity is 0, i.e., the vehicle is traveling straight; and the case where the steering wheel angular velocity is not 0, i.e., the vehicle may be transitioning from turning to turning in one direction to turning in the other, and the steering wheel has passed the center position. Both of these cases are considered as completion of the return-to-center process, at which point the maximum hand torque applied during the steering wheel's movement away from the center position is reset to zero.

[0055] In summary, if either the return-to-center process is interrupted or completed, the maximum hand torque during the steering wheel's movement away from the center position will be reset to zero, and the maximum hand torque will be recorded again during the next steering wheel movement away from the center position. If the return-to-center process is not interrupted and the steering wheel angular velocity is not zero, the step of resetting the maximum hand torque to zero will not be performed.

[0056] In some optional embodiments, the step of obtaining the maximum hand torque during the process of the steering wheel moving away from the center position based on the steering wheel angle and the actual hand torque includes: performing low-pass filtering on the data of the steering wheel angle and the actual hand torque. Low-pass filtering is a filtering method where low-frequency signals can pass normally, while high-frequency signals exceeding a set threshold are blocked or weakened to filter out interference signals.

[0057] Embodiments of the present invention also provide an active return-to-center control device. The active return-to-center control device includes: a data acquisition module 1, a judgment module 2, and a calculation module 3. The data acquisition module 1 is used to acquire the steering wheel angle and the actual hand torque; the judgment module 2 is used to acquire the maximum hand torque during the steering wheel's movement away from the center position based on the steering wheel angle and the actual hand torque; the calculation module 3 is used to compare the actual hand torque and the maximum hand torque to acquire a return-to-center torque coefficient, and based on the return-to-center torque coefficient and the calculated return-to-center control torque, obtain the final return-to-center torque to control the steering wheel to actively return to center.

[0058] Furthermore, the calculation module is configured to obtain a return torque coefficient based on the difference between the actual hand torque and the maximum hand torque. The return torque coefficient characterizes the driver's intention to release the handle. The larger the difference between the actual hand torque and the maximum hand torque, the greater the driver's intention to release the handle, the greater the required return torque, and thus the larger the return torque coefficient; conversely, the smaller the difference between the actual hand torque and the maximum hand torque, the smaller the driver's intention to release the handle, the smaller the required return torque, and thus the smaller the return torque coefficient.

[0059] In some embodiments, the data acquisition module includes a steering wheel angle sensor, a speed sensor, and a hand torque sensor.

[0060] In some embodiments, a steering wheel angle sensor is used to acquire the steering wheel angle, and a speed sensor is used to acquire the vehicle speed. The calculation module is configured to obtain the return-to-center control calculation torque based on the steering wheel angle, vehicle speed, and a proportional-integral-derivative (PID) control algorithm.

[0061] The calculation module provides a proportional-integral-derivative (PID) control algorithm to implement a PID control strategy. PID control combines proportional, derivative, and integral control and can be implemented using a PID controller. Specifically, the calculation module can determine the return torque based on the steering wheel angle, vehicle speed, and the PID control algorithm provided by the data acquisition module. Furthermore, the calculation module can determine a matching correction coefficient based on the steering wheel speed and the actual hand torque applied to the steering wheel; the calculation module corrects the return torque based on the correction coefficient and obtains the calculated return control torque based on the corrected return torque.

[0062] In some embodiments, when the return-to-center process is stopped or completed, the determination module is configured to reset the maximum hand torque during the process of moving the steering wheel away from the center position to zero.

[0063] Specifically, the judgment module is configured to determine whether the return-to-center process has been aborted based on the steering wheel angular velocity and the steering wheel turning direction, and to determine whether the return-to-center process has been completed based on the steering wheel turning angle.

[0064] Furthermore, the judgment module is configured as follows: when the direction of the steering wheel angular velocity is opposite to the direction of the steering wheel angle, the centering process is determined to have not been interrupted; when the direction of the steering wheel angular velocity is not opposite to the direction of the steering wheel angle, the centering process is determined to have been interrupted; when the steering wheel angle is zero, the centering process is determined to have been completed; when the steering wheel angle is not zero, the centering process is determined to have not been completed.

[0065] This invention determines the driver's intention to release the handle by the trend of the change in hand torque, rather than by the absolute value of the hand torque. This reduces misjudgment of the driver's intention to release the handle and improves the response speed of the return to center.

[0066] The residual torque of steering systems varies across different vehicles. Calibrating the return torque coefficient using the absolute value of the hand torque would not provide a unified parameter, increasing the difficulty of calibration. However, by judging the driver's intention to release the steering wheel based on the trend of hand torque changes, different residual torques can be covered, increasing the robustness of the active return control device and simplifying the calibration process.

[0067] Furthermore, the left and right symmetry of the steering system of the same vehicle also differs, resulting in inconsistent residual torque on the left and right sides. By judging the driver's intention to release the steering wheel by the trend of the change in hand torque, the problem of left and right symmetry cannot be taken into account when using a set of return torque coefficients in related technologies can be solved. Thus, the difference between the left and right sides is avoided and the robustness is improved.

[0068] While possible embodiments have been described exemplarily in the foregoing description, it should be understood that numerous variations of the embodiments exist through all known and readily apparent combinations of technical features, variations, and implementation methods. For example, the maximum torque during the return-to-center process can also be varied as an average value during the process away from the steering wheel center, or as a real-time value of the torque at the moment the process stops away from the steering wheel center. Furthermore, it should be understood that the exemplary embodiments are merely examples and do not in any way limit the scope, application, or construction of the invention. The foregoing description is more intended to provide those skilled in the art with technical guidance for transforming at least one exemplary embodiment, wherein various changes can be made, particularly regarding changes to the function and structure of the components, without departing from the scope of the claims.

Claims

1. An active self-alignment control method, characterized in that, include: Collect steering wheel angle and actual hand torque; The maximum hand torque is obtained by measuring the steering wheel angle and the actual hand torque as the steering wheel moves away from the center position. The return torque coefficient is obtained by comparing the actual hand torque with the maximum hand torque. as well as Based on the return torque coefficient and the return control calculated torque, the final return torque is obtained to control the steering wheel to actively return to center.

2. The active homing control method according to claim 1, characterized in that, The step of comparing the actual hand torque with the maximum hand torque to obtain the return torque coefficient includes: The greater the difference between the actual hand torque and the maximum hand torque, the greater the return torque coefficient; the smaller the difference between the actual hand torque and the maximum hand torque, the smaller the return torque coefficient.

3. The active homing control method according to claim 1, characterized in that, The return-to-center control calculation torque is obtained based on the steering wheel angle, vehicle speed, and proportional-integral-derivative control algorithm.

4. The active homing control method according to claim 1, characterized in that, When the return-to-center process is stopped or completed, the maximum hand torque during the process of moving the steering wheel away from the center position is reset to zero.

5. The active homing control method according to claim 4, characterized in that, Determine whether the return-to-center process has stopped based on the steering wheel angular velocity and steering wheel turning direction, and determine whether the return-to-center process has been completed based on the steering wheel turning angle.

6. The active homing control method according to claim 5, characterized in that, When the direction of the steering wheel angular velocity is opposite to the direction of the steering wheel angle, it is determined that the straightening process has not been interrupted; when the direction of the steering wheel angular velocity is not opposite to the direction of the steering wheel angle, it is determined that the straightening process has not been interrupted. If this happens, the correction process is considered to have stopped. When the steering wheel angle is zero, the process of straightening the steering wheel is considered complete. If the steering wheel angle is not zero, it is determined that the return-to-center process is not complete.

7. The active homing control method according to claim 1, characterized in that, The steps for obtaining the maximum hand torque during the process of the steering wheel moving away from the center position based on the steering wheel angle and the actual hand torque include: performing low-pass filtering on the data of the steering wheel angle and the actual hand torque.

8. An active return-to-center control device, characterized in that, include: The data acquisition module is used to obtain the steering wheel angle and actual hand torque; The judgment module is used to obtain the maximum hand torque during the process of the steering wheel moving away from the center position based on the steering wheel angle and the actual hand torque; The calculation module is used to compare the actual hand torque with the maximum hand torque to obtain the return torque coefficient, and to obtain the final return torque based on the return torque coefficient and the return control calculation torque, so as to control the steering wheel to actively return to center.

9. The active return-to-center control device according to claim 8, characterized in that, The calculation module is configured to obtain the return torque coefficient based on the difference between the actual hand torque and the maximum hand torque; the larger the difference between the actual hand torque and the maximum hand torque, the larger the return torque coefficient; the smaller the difference between the actual hand torque and the maximum hand torque, the smaller the return torque coefficient.

10. The active return-to-center control device according to claim 8, characterized in that, The data acquisition module includes a steering wheel angle sensor, a speed sensor, and a hand torque sensor.

11. The active return-to-center control device according to claim 10, characterized in that, The steering wheel angle sensor is used to acquire the steering wheel angle, and the speed sensor is used to acquire the vehicle speed. The calculation module is configured to obtain the return-to-center control calculation torque based on the steering wheel angle, vehicle speed, and proportional-integral-derivative control algorithm.

12. The active return-to-center control device according to claim 8, characterized in that, When the return-to-center process is stopped or completed, the judgment module is configured to reset the maximum hand torque during the process of moving the steering wheel away from the center position to zero.

13. The active return-to-center control device according to claim 12, characterized in that, The judgment module is configured to determine whether the return-to-center process has stopped based on the steering wheel angular velocity and the steering wheel turning direction, and to determine whether the return-to-center process has been completed based on the steering wheel turning angle.

14. The active return-to-center control device according to claim 13, characterized in that, The judgment module is configured as follows: When the direction of the steering wheel angular velocity is opposite to the direction of the steering wheel angle, it is determined that the centering process has not been interrupted; when the direction of the steering wheel angular velocity is not opposite to the direction of the steering wheel angle, it is determined that the centering process has been interrupted. When the steering wheel angle is zero, the process of straightening the steering wheel is considered complete. If the steering wheel angle is not zero, it is determined that the return-to-center process is not complete.

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