Steering control method and apparatus

Abstract

The present invention relates to a steering control method and an apparatus. The steering control method comprises: on the basis of the current hand force of a driver, a vehicle speed, a steering wheel angle and a steering wheel angular speed, obtaining a demanded alignment torque so as to perform auxiliary control on the alignment of a vehicle, comprising: on the basis of the turning direction of the steering wheel and the current hand force of the driver, obtaining an alignment torque coefficient; on the basis of the vehicle speed, the steering wheel angle and the steering wheel angular speed, obtaining an initial demanded alignment torque; and, on the basis of the alignment torque coefficient and the initial demanded alignment torque, obtaining the demanded alignment torque. The steering control method ameliorates the problem of inconsistency of alignment speeds and alignment residual angles of the left side and the right side of a vehicle electro-hydraulic coupling steering system, and can effectively reduce takeover impacts on hands of drivers in alignment processes.

Description

Steering control method and device Technical Field

[0001] The present invention relates to the technical field of steering control, and in particular to a steering control method and device. Background Art

[0002] Current vehicle steering control technology typically uses closed-loop control for the return speed during the steering return process. First, a table lookup is performed to obtain the target steering wheel speed based on the steering wheel angle and vehicle speed. The difference between the target speed and the actual speed is then proportionally controlled in a closed-loop manner to determine the initial return torque requirement. This is then used to determine the return torque based on the return torque coefficient.

[0003] However, the electronic hydraulic power steering (EHPS) system for commercial vehicles suffers from inconsistent left and right steering angles due to component manufacturing variations and assembly coaxiality. Directly controlling the return torque based on the driver's absolute hand force can easily lead to inconsistent return speeds and, consequently, different residual return angles.

[0004] Furthermore, when the driver's hand force difference is small, current steering control technology does not consider the integral term in closed-loop control. Therefore, when the driver intervenes to terminate the return process, the vehicle's power steering will cause a shock to the driver's hand when taking over the return process.

[0005] Summary of the Invention

[0006] In order to overcome the problems existing in the related art, the present invention provides a steering control method and device.

[0007] According to a first aspect of an embodiment of the present invention, a steering control method is provided for obtaining a return torque based on a driver's current hand force, vehicle speed, steering wheel angle, and steering wheel angular velocity, thereby assisting in vehicle return control. The steering control method comprises: obtaining a return torque coefficient based on the steering wheel angle and the driver's current hand force; obtaining an initial return torque coefficient based on the vehicle speed, steering wheel angle, and steering wheel angular velocity; and obtaining a return torque coefficient based on the initial return torque coefficient.

[0008] In some embodiments, obtaining the return torque coefficient based on the steering wheel angle and the driver's current hand force includes: obtaining the maximum value of the driver's hand force based on the driver's current hand force during the process of the steering direction of the steering wheel moving away from the return direction; and obtaining the return torque coefficient based on the maximum value of the driver's hand force and the driver's current hand force.

[0009] In some embodiments, when the driver's current hand force in the direction opposite to the return-to-center direction is applied, if the steering wheel angular velocity in the direction opposite to the return-to-center direction is greater than a preset angular velocity threshold, the maximum value of the driver's hand force is reset.

[0010] In some embodiments, obtaining the initial return torque requirement based on the vehicle speed, steering wheel angle and steering wheel angular velocity includes: calculating the return target angular velocity based on the vehicle speed and the steering wheel angle, calculating the steering wheel angular velocity, calculating the absolute value of the difference between the return target angular velocity and the steering wheel angular velocity, obtaining the steering wheel angular velocity difference, inputting the steering wheel angular velocity difference into a proportional integral differential (PID) controller, and obtaining the initial return torque requirement.

[0011] In some embodiments, when the return torque coefficient is less than a calibrated threshold, the I term in the PID controller is cleared.

[0012] In some embodiments, obtaining the return required torque based on the return torque coefficient and the initial return required torque includes: inputting the product of the return torque coefficient and the initial return required torque into a limiter to obtain the return required torque, so as to limit the maximum and minimum values ​​of the return required torque.

[0013] In some embodiments, the limiter defines a maximum value and a minimum value of the return torque based on the vehicle speed and the steering wheel angle.

[0014] According to a second aspect of an embodiment of the present invention, the present invention provides a steering control device, wherein the steering control device is configured to obtain a return torque based on the driver's current hand force, vehicle speed, steering wheel angle, and steering wheel angular velocity to assist in controlling the vehicle's return to centering. The steering control device includes: a return torque coefficient calculation unit configured to calculate a return torque coefficient based on the steering wheel angle and the driver's current hand force; an initial return torque calculation unit configured to calculate an initial return torque based on the vehicle speed, steering wheel angle, and steering wheel angular velocity; and a return torque calculation unit configured to calculate a return torque based on the return torque coefficient and the initial return torque.

[0015] In some embodiments, the return torque coefficient calculation unit is further configured to: obtain the maximum value of the driver's hand force based on the driver's current hand force when the steering direction of the steering wheel is moving away from the return direction; and obtain the return torque coefficient based on the maximum value of the driver's hand force and the driver's current hand force.

[0016] In some embodiments, the return torque coefficient calculation unit is further configured to: reset the maximum value of the driver's hand force when the driver's current hand force is applied in the opposite direction to the return direction and the steering wheel angular velocity in the opposite direction to the return direction is greater than a preset angular velocity threshold.

[0017] In some embodiments, the righting torque coefficient calculation unit is further configured to: calculate the absolute value of the difference between the maximum value of the driver's hand force and the driver's current righting hand force to obtain the hand force difference, and obtain the righting torque coefficient based on the hand force difference.

[0018] In some embodiments, the initial return-to-center required torque calculation unit includes a PID controller, wherein the initial return-to-center required torque calculation unit is further configured to: calculate the return-to-center target angular velocity based on the vehicle speed and the steering wheel angle, calculate the steering wheel angular velocity, calculate the absolute value of the difference between the return-to-center target angular velocity and the steering wheel angular velocity, obtain the steering wheel angular velocity difference, input the steering wheel angular velocity difference into the PID controller, and obtain the initial return-to-center required torque.

[0019] In some embodiments, the initial return-to-normal torque calculation unit is further configured to: when the return-to-normal torque coefficient is less than a calibrated threshold, clear the I term in the PID controller to zero.

[0020] In some embodiments, the return-to-normal torque calculation unit includes a limiter, wherein the return-to-normal torque calculation unit is further configured to: obtain the return-to-normal torque by inputting the product of the return-to-normal torque coefficient and the initial return-to-normal torque into the limiter to limit the maximum and minimum values ​​of the return-to-normal torque.

[0021] In some embodiments, the limiter is configured to limit a maximum value and a minimum value of the return-to-center torque based on the vehicle speed and the steering wheel angle.

[0022] The steering control method and device provided by embodiments of the present invention utilizes hand force differential for self-centering control in an EHPS system, thereby optimizing the problem of inconsistent self-centering speeds and residual self-centering angles on the left and right sides of a vehicle's electro-hydraulic coupled steering system. Furthermore, the present invention implements PID closed-loop control of the self-centering torque. When the driver's hand force differential falls below a preset threshold, the PID closed-loop control resets the first term to zero. This effectively reduces the perceived impact of the driver taking control of the self-centering process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0024] FIG1 shows a schematic diagram of a steering control method according to some embodiments;

[0025] FIG2 shows a schematic diagram of a workflow of a steering control method according to some embodiments; and

[0026] FIG3 shows a structural block diagram of a steering control device according to some embodiments. DETAILED DESCRIPTION

[0027] Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, like numbers in different figures represent like or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present invention, as detailed in the appended claims.

[0028] In the steering control of a vehicle, in order to optimize the influence of the driver's hand force on the right and left side return speeds and improve the control robustness, the present invention proposes a steering control method.

[0029] According to an embodiment of the present invention, FIG1 shows a schematic diagram of a steering control method according to some embodiments, and FIG2 shows a schematic diagram of a working process of a steering control method according to some embodiments. In combination with FIG1 and FIG2, the steering control method is based on the driver's current hand force HT, vehicle speed V, steering wheel angle AG and steering wheel angular velocity AgSpd. ACT Obtaining the required return torque RT to assist in controlling the return of the vehicle. Specifically, the steering control method includes:

[0030] S100: Obtaining the return torque coefficient RT based on the steering wheel angle AG and the driver's current hand force HT fac ;

[0031] S200: Based on vehicle speed V, steering wheel angle AG and steering wheel angular velocity AgSpd ACT Get the initial return torque RT RAW ;as well as

[0032] S300: Based on the return torque coefficient RT fac and the initial return torque RT RAW Obtain the return required torque RT.

[0033] As shown in FIG2 , in step S100 , during the process of the steering wheel turning direction D being in the direction opposite to the return direction, the driver's current hand force HT is recorded. The driver's current hand force HT may vary from moment to moment. For example, in actual operation, during the process of the steering wheel turning in the direction opposite to the return direction, the driver's current hand force HT at the initial moment is recorded as the maximum value of the driver's hand force HT. max If the driver's current hand force HT at the next moment is greater than the maximum hand force HT of the driver before max When the driver's current hand force HT at the next moment replaces the maximum hand force HT of the driver at the previous moment max , as the updated maximum value of the driver's hand force HT max If the driver's current hand force HT at the next moment is less than or equal to the maximum hand force HT of the driver before max The maximum value of the driver's hand force HT at the previous moment is still retained. max , in order to obtain the maximum value HT of the driver's hand force under the current state max .

[0034] In some embodiments, the steering wheel angular velocity AgSpd is also considered ACT To obtain the maximum value of the driver's hand force HT max Specifically, when the driver's current hand force HT is applied in the direction opposite to the return direction, the steering wheel angular velocity AgSpd in the direction opposite to the return direction is ACT When the angular velocity is greater than the preset threshold, the maximum value of the driver's hand force HT max Reset to current hand force value.

[0035] For example, when the steering wheel moves in the direction of returning to the center, if the driver applies the current hand force HT in the direction opposite to the direction of returning to the center, only when the steering wheel angular velocity AgSpd in the direction opposite to the direction of returning to the center is ACT When the angular velocity is greater than the preset threshold, the maximum value of the driver's hand force HT is reset. max , so as to avoid the influence of power steering return due to slight adjustment of the steering wheel by the driver.

[0036] Furthermore, the maximum value HT of the driver's hand force is calculated max The absolute value of the difference between the current hand force HT of the driver to obtain the hand force difference HT diff .

[0037] It should be understood that the maximum value of the driver's hand force HT max The difference between the current hand force HT of the driver is the vector difference. That is, when the maximum hand force HT of the driver is max When the hand force difference HT is in the same direction as the driver's current hand force HT diffEqual to the maximum value of the driver's hand force HT max The absolute value of the driver's current hand force HT minus the absolute value of the difference; when the maximum value of the driver's hand force HT max When the driver's current hand force HT is in the opposite direction, the hand force difference HT diff Equal to the maximum value of the driver's hand force HT max The sum of the absolute value of and the absolute value of the driver's current righting hand force HT.

[0038] Furthermore, based on the hand force difference HT diff As an input item, the return torque coefficient RT can be obtained by looking up a table, for example: fac Wherein, the return torque coefficient RT fac With HT diff By using the hand force difference HT diff Performing return control can optimize the problem of inconsistent return speed and return residual angle on the left and right sides of the vehicle's electro-hydraulic coupled steering system.

[0039] In some embodiments, the vehicle speed V, the steering wheel angle AG and the steering wheel angular velocity AgSpd ACT Get the initial return torque RT RAW The vehicle speed V and the steering wheel angle AG are used as input items, and the return target angular velocity AgSpd can be obtained by, for example, looking up a table. tar ; Get the steering wheel angular velocity AgSpd ACT ; Calculate the return target angular velocity AgSpd tar and the steering wheel angular velocity AgSpd ACT The absolute value of the difference is used to obtain the steering wheel angular velocity difference AgSpd diff .

[0040] It should be understood that the return target angular velocity AgSpd tar and the steering wheel angular velocity AgSpd ACT The difference is the vector difference. Wherein, the return target angular velocity AgSpd tar The direction is towards the direction of returning to the center, and the steering wheel angular velocity AgSpd ACT The direction is the direction of the current steering wheel angular velocity.

[0041] Furthermore, the steering wheel angular velocity difference AgSpd diff Input the proportional integral derivative (PID) controller 21 to obtain the initial return torque RT RAW .

[0042] The steering wheel angular velocity difference AgSpd diffInput into the PID controller 21, the proportional amplification term (P term), the integral term (I term) and the differential term (D term) are added to obtain the initial return torque RT RAW In some embodiments, when the return torque coefficient RT fac When the maximum hand force of the driver HT is less than the calibrated threshold, the I item in the PID controller is cleared. max When the absolute value of the difference between the driver's current hand force HT and the driver's current hand force HT is small, that is, the hand force difference HT diff When it is smaller, the return torque coefficient RT will be fac If the value is less than the calibration threshold, the I term in the PID controller is reset to zero. Therefore, during the return process, the impact of the driver taking over the return process can be effectively reduced.

[0043] In some embodiments, the return torque coefficient RT fac and the initial return torque RT RAW Obtaining the return torque requirement RT includes: converting the return torque coefficient RT fac and the initial return torque RT RAW The product of ΔV and ΔG is input into a limiter 31 to obtain the return torque RT. The limiter 31 can be used to limit the maximum and minimum values ​​of the return torque RT. The limiter 31 limits the maximum and minimum values ​​of the return torque RT based on the vehicle speed V and the steering wheel angle AG.

[0044] The present invention proposes a steering control device. FIG3 shows a structural block diagram of a steering control device according to some embodiments. In conjunction with FIG2-3, the steering control device is configured to be based on the driver's current hand force HT, vehicle speed V, steering wheel angle AG and steering wheel angular velocity AgSpd. ACT Obtaining the required return torque RT to assist in controlling the return of the vehicle.

[0045] The return torque coefficient calculation unit 1 is configured to calculate the return torque coefficient RT based on the steering wheel angle AG and the driver's current hand force HT fac ;

[0046] The initial return torque calculation unit 2 is configured to calculate the initial return torque RT based on the vehicle speed V, the steering wheel angle AG and the steering wheel angular velocity AgSpdACT RAW ;as well as

[0047] The return torque calculation unit 3 is configured to calculate the return torque coefficient RT based on the return torque coefficient RT. fac and the initial return torque RT RAWCalculate and obtain the required return torque RT.

[0048] In some embodiments, the return torque coefficient calculation unit 1 is further configured to: when the steering direction D of the steering wheel is moving in the opposite direction to the return torque, obtain the maximum value of the driver's hand force HT based on the driver's current hand force HT max ; and, based on the maximum value HT of the driver's hand force max The return torque coefficient RT is obtained by using the driver's current hand force HT fac When the driver's current hand force HT is applied in the direction opposite to the return direction, and the steering wheel angular velocity AgSpd in the direction opposite to the return direction is ACT When the angular velocity is greater than the preset threshold, the maximum value HT of the driver's hand force is reset. max , so that the maximum value of the driver's hand force HT max It can be updated in real time according to the changes in the driver's real-time control of the steering wheel, thereby enabling the return control of the steering control device to be adjusted in real time.

[0049] In some embodiments, the return torque coefficient calculation unit 1 is further configured to calculate the maximum value HT of the driver's hand force max The absolute value of the difference between the current hand force HT of the driver and the hand force difference HT is obtained diff , and based on the hand strength difference HT diff Get the return torque coefficient RT fac Among them, the hand force difference HT diff As an input item, the return torque coefficient RT can be obtained by looking up a table, for example: fac The return torque coefficient RT fac With HT diff Increase and grow.

[0050] In some embodiments, the initial return torque calculation unit 2 further includes a PID controller 21; wherein, the initial return torque calculation unit 2 is further configured to: calculate the return target angular velocity AgSpd based on the vehicle speed V and the steering wheel angle AG tar , calculate and obtain the steering wheel angular velocity AgSpd ACT , calculate the return target angular velocity AgSpd tar and the steering wheel angular velocity AgSpd ACT The absolute value of the difference is used to obtain the steering wheel angular velocity difference AgSpd diff , the steering wheel angular velocity difference AgSpd diff Input into the PID controller 21 to obtain the initial return torque RT RAW .

[0051] The initial return torque calculation unit 2 is further configured to: when the return torque coefficient RT fac When it is less than the calibrated threshold, the I item in the PID controller 21 is reset to zero, thereby effectively reducing the impact of the driver taking over during the return process.

[0052] In some embodiments, the return torque requirement calculation unit 3 further includes a limiter 31. The return torque requirement calculation unit 3 is further configured to: fac and the initial return torque RT RAW The product of and is input into the limiter 31 to obtain the return torque RT, so as to limit the maximum value and the minimum value of the return torque RT.

[0053] Specifically, the limiter 31 is configured to limit the maximum and minimum values ​​of the return torque RT based on the vehicle speed V and the steering wheel angle AG, so that the return torque RT can be limited to a certain range according to the real-time state of the vehicle, avoiding the return torque RT being too large or too small.

[0054] Through the steering control method and device provided by the embodiment of the present invention, in the EHPS system, the hand force difference HT diff The return control can optimize the problem of inconsistent return speed and return residual angle on the left and right sides of the vehicle's electro-hydraulic coupled steering system. In addition, the present invention performs PID closed-loop control on the return torque; when the driver's hand force difference HT diff When it is less than the preset threshold, the PID closed-loop control takes the I item to zero; therefore, during the return process, the impact of the driver taking over the return process can be effectively reduced.

[0055] It should be further understood that, although operations are described in a particular order in the accompanying drawings in the embodiments of the present invention, this should not be construed as requiring that the operations be performed in the particular order shown or in a serial order, or that all of the operations shown be performed to obtain the desired results. In certain circumstances, multitasking and parallel processing may be advantageous.

[0056] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, and the true scope and spirit of the invention are indicated by the following claims.

[0057] It should be understood that the present invention is not limited to the exact structure described above and shown in the drawings, and that various modifications and changes can be made without departing from the scope thereof. The scope of the present invention is limited only by the scope of the appended claims.

Claims

1. A steering control method, characterized in that: Based on the driver's current hand force (HT), vehicle speed (V), steering wheel angle (AG) and steering wheel angular velocity (AgSpd ACT ) obtains the return torque (RT) to assist in the return of the vehicle; wherein, The return torque coefficient (RT) is obtained based on the steering wheel angle (AG) and the driver's current hand force (HT). fac ); Based on vehicle speed (V), steering wheel angle (AG) and steering wheel angular velocity (AgSpd ACT ) to obtain the initial return torque (RT RAW );as well as Based on the return torque coefficient (RT fac ) and the initial return torque requirement (RT RAW ) to obtain the return required torque (RT).

2. The steering control method according to claim 1, characterized in that: The return torque coefficient (RT) is obtained based on the steering wheel angle (AG) and the driver's current hand force (HT) fac )include: When the steering direction (D) of the steering wheel is moving from the reverse direction to the forward direction, the maximum value of the driver's hand force (HT) is obtained based on the driver's current hand force (HT). max ); and, based on the maximum value of the driver's hand force (HT max ) and the driver's current hand force (HT) to obtain the return torque coefficient (RT fac ).

3. The steering control method according to claim 2, characterized in that: When the driver's current hand force (HT) is applied in the direction opposite to the return direction, and the steering wheel angular velocity (AgSpd ACT ) is greater than a preset angular velocity threshold, the maximum value of the driver's hand force (HT max ).

4. The steering control method according to claim 2, characterized in that: Calculate the maximum value of the driver's hand force (HT max ) and the absolute value of the difference between the current hand force (HT) of the driver to obtain the hand force difference (HT diff ), and hand strength difference (HT diff ) to obtain the return torque coefficient (RT fac ).

5. The steering control method according to claim 1, characterized in that: The vehicle speed (V), steering wheel angle (AG) and steering wheel angular velocity (AgSpd ACT ) to obtain the initial return torque (RT RAW )include: The return target angular velocity (AgSpd) is calculated based on the vehicle speed (V) and the steering wheel angle (AG). tar ); obtain the steering wheel angular velocity (AgSpd ACT ); Calculate the return target angular velocity (AgSpd tar ) and the steering wheel angular velocity (AgSpd ACT ) to obtain the steering wheel angular velocity difference (AgSpd diff ); the steering wheel angular velocity difference (AgSpd diff ) is input into the proportional integral derivative (PID) controller (21) to obtain the initial return torque requirement (RT RAW ).

6. The steering control method according to claim 5, characterized in that: When the return torque coefficient (RT fac ) is less than a calibration threshold, the I item in the PID controller (21) is cleared.

7. The steering control method according to claim 1, characterized in that: The return torque coefficient (RT fac ) and the initial return torque requirement (RT RAW ) to obtain the return torque (RT) including: The return torque coefficient (RT fac ) and the initial return torque requirement (RT RAW ) is multiplied by the input into the limiter (31) to obtain the return torque (RT) so as to limit the maximum value and the minimum value of the return torque (RT).

8. The steering control method according to claim 7, characterized in that: The limiter (31) limits the maximum value and the minimum value of the return-to-centering torque (RT) based on the vehicle speed (V) and the steering wheel angle (AG).

9. A steering control device, characterized in that: The steering control device is configured to control the steering wheel angle (AG) and the steering wheel angular velocity (AgSpd) based on the driver's current hand force (HT), vehicle speed (V), steering wheel angle (AG) and steering wheel angular velocity (AgSpd ACT ) obtaining a return-to-centering torque (RT) to assist in controlling the return-to-centering of the vehicle; Wherein, the steering control device comprises: The return torque coefficient calculation unit (1) is configured to calculate the return torque coefficient (RT) based on the steering wheel angle (AG) and the driver's current hand force (HT). fac ); The initial return torque calculation unit (2) is configured to calculate the initial return torque (RT) based on the vehicle speed (V), the steering wheel angle (AG) and the steering wheel angular velocity (AgSpdACT). RAW );as well as The return torque requirement calculation unit (3) is configured to calculate the return torque coefficient (RT fac ) and the initial return torque requirement (RT RAW ) is used to calculate the return torque requirement (RT).

10. The steering control device according to claim 9, characterized in that: The return torque coefficient calculation unit (1) is further configured to: when the steering direction (D) of the steering wheel is moving in the opposite direction to the return direction, obtain the maximum value (HT) of the driver's hand force based on the driver's current hand force (HT) max );as well as , based on the maximum value of the driver's hand force (HT max ) and the driver's current hand force (HT) to obtain the return torque coefficient (RT fac ).

11. The steering control device according to claim 10, characterized in that: The return torque coefficient calculation unit (1) is further configured to: when the driver's current hand force (HT) is applied in the direction opposite to the return direction, and the steering wheel angular velocity (AgSpd ACT ) is greater than a preset angular velocity threshold, the maximum value of the driver's hand force (HT max ).

12. The steering control device according to claim 10, characterized in that: The return torque coefficient calculation unit (1) is further configured to calculate the maximum value of the driver's hand force (HT max ) and the absolute value of the difference between the current hand force (HT) of the driver to obtain the hand force difference (HT diff ), and hand strength difference (HT diff ) to obtain the return torque coefficient (RT fac ).

13. The steering control device according to claim 9, characterized in that: The initial return-to-center torque calculation unit (2) includes a proportional integral differential controller (PID controller) (21), wherein the initial return-to-center torque calculation unit (2) is further configured to: calculate a return-to-center target angular velocity (AgSpd) based on the vehicle speed (V) and the steering wheel angle (AG) tar ), calculate the steering wheel angular velocity (AgSpd ACT ), calculate the return target angular velocity (AgSpd tar ) and the steering wheel angular velocity (AgSpd ACT ) to obtain the steering wheel angular velocity difference (AgSpd diff ), the steering wheel angular velocity difference (AgSpd diff ) is input into the PID controller (21) to obtain the initial return torque requirement (RT RAW ).

14. The steering control device according to claim 13, characterized in that: The initial return torque calculation unit (2) is further configured to: when the return torque coefficient (RT fac ) is less than a calibration threshold, the I item in the PID controller (21) is cleared.

15. The steering control device according to claim 9, characterized in that: The return torque requirement calculation unit (3) comprises a limiter (31), wherein the return torque requirement calculation unit (3) is further configured to: fac ) and the initial return torque requirement (RT RAW ) is multiplied by the input limiter (31) to obtain the return torque (RT) to limit the maximum and minimum values ​​of the return torque (RT).

16. The steering control device according to claim 15, characterized in that: The limiter (31) is configured to limit a maximum value and a minimum value of the return-to-centering torque (RT) based on the vehicle speed (V) and the steering wheel angle (AG).

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