Steering return debugging method and device of electric power steering system

Abstract

The invention relates to the technical field of EPS steering adjustment, in particular to a steering return adjustment method and device of an electric power steering system.The method comprises the steps that low-speed working condition steering, middle position steering and large-turning-angle steering are conducted on a target vehicle; establishing a return coefficient-hand moment curve, a lateral acceleration-hand moment curve and a steering wheel angle-return coefficient curve; performing aligning torque analysis on the lateral acceleration-hand torque curve to obtain an aligning torque state; adjusting the aligning coefficient-hand torque curve according to the aligning torque state so as to complete aligning torque debugging of the electric power steering system; performing return speed analysis on the steering wheel angle-return coefficient curve to determine a return speed state; and adjusting the return coefficient-hand torque curve according to the return speed state so as to complete the return speed debugging of the electric power steering system. Therefore, the problem of how to adjust the electric power steering system in a steering mode to achieve the optimal steering hand feeling is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of EPS steering calibration, and particularly to a steering return calibration method and device for an electric power steering system. Background Art

[0002] The function of the steering system is to control the driving direction of the vehicle according to the driver's intention, which plays a crucial role in the driving safety of the vehicle. The steering system is the most important way for the vehicle to feedback to the driver. Whether the steering system is sensitive or not determines the most intuitive feeling of the driver towards a vehicle model. Steering calibration is mainly carried out for the electric power steering system (EPS). The role of EPS is to provide a assist torque through an assist motor to reduce the torque required for the driver to turn the steering wheel. By debugging the steering assist torque, the steering force, return and other performances in different vehicle speed ranges are determined, so that the steering system can better match the driver's control intention and feedback appropriate road feeling to the driver in any driving environment. The main elements of EPS steering calibration include assist, return and damping. How to debug an excellent steering feel, the steering return calibration is crucial. Summary of the Invention

[0003] The present invention provides a steering return calibration method and device for an electric power steering system to solve the problem of how to calibrate the electric power steering system to achieve the optimal steering feel.

[0004] In a first aspect embodiment of the present invention, a steering return calibration method for an electric power steering system is provided, including the following steps: performing low-speed condition steering, middle position steering and large-angle steering on a target vehicle respectively to establish a return coefficient - hand torque curve, a lateral acceleration - hand torque curve and a steering wheel angle - return coefficient curve; performing a return torque analysis on the lateral acceleration - hand torque curve to obtain a return torque state; adjusting the return coefficient - hand torque curve according to the return torque state to complete the return torque calibration of the electric power steering system; performing a return speed analysis on the steering wheel angle - return coefficient curve to determine a return speed state; adjusting the return coefficient - hand torque curve according to the return speed state to complete the return speed calibration of the electric power steering system.

[0005] Optionally, the return torque state includes at least two of strong return torque in the central region, normal return torque in the central region, strong return torque at large angles and normal return torque at large angles.

[0006] Optionally, the return speed state includes at least one of fast return speed, slow return speed and normal return speed.

[0007] Optionally, performing a restoring moment analysis on the lateral acceleration-hand moment curve to obtain a restoring moment state, including:

[0008] Obtaining the steering starting moment at different vehicle speeds in the lateral acceleration-hand moment curve;

[0009] Comparing the steering starting moments at adjacent vehicle speeds in sequence to obtain multiple comparison results. If there is a case where the multiple comparison results are greater than a preset value, then the restoring moment state is that the restoring moment in the central region is strong; otherwise, the restoring moment state is that the restoring moment in the central region is normal;

[0010] Determining whether there is a moment asymmetry region in the lateral acceleration-hand moment curve. If there is the moment asymmetry region, then the restoring moment state is that the restoring moment at large steering angles is strong; otherwise, the restoring moment state is that the restoring moment at large steering angles is normal.

[0011] Optionally, adjusting the restoring coefficient-hand moment curve according to the restoring moment state to complete the restoring moment debugging of the electric power steering system, including:

[0012] When the restoring moment state is that the restoring moment in the central region is strong, weakening the restoring coefficient in the corresponding region of the restoring coefficient-hand moment curve until there is no case where the multiple comparison results are greater than the preset value;

[0013] When the restoring moment state is that the restoring moment at large steering angles is strong, weakening the hand moment in the corresponding region of the restoring coefficient-hand moment curve until there is no such moment asymmetry region;

[0014] When the restoring moment state is that the restoring moment in the central region is normal or the restoring moment at large steering angles is normal, there is no need to adjust the restoring coefficient-hand moment curve.

[0015] Optionally, adjusting the restoring coefficient-hand moment curve according to the restoring speed state to complete the restoring speed debugging of the electric power steering system, including:

[0016] When the restoring speed state is that the restoring speed is fast, weakening the restoring coefficient and the hand moment in the corresponding region of the restoring coefficient-hand moment curve until the restoring speed and the hand moment meet the target requirements;

[0017] When the restoring speed state is that the restoring speed is slow, increasing the restoring coefficient and the hand moment in the corresponding region of the restoring coefficient-hand moment curve until the restoring speed and the hand moment meet the target requirements;

[0018] When the return speed state is normal, there is no need to adjust the return coefficient - hand torque curve.

[0019] An embodiment of the second aspect of the present invention provides a steering return debugging device for an electric power steering system, including: a curve establishment module, configured to perform low-speed condition steering, middle position steering, and large-angle steering on a target vehicle respectively to establish a return coefficient - hand torque curve, a lateral acceleration - hand torque curve, and a steering wheel angle - return coefficient curve; a return torque analysis module, configured to perform return torque analysis on the lateral acceleration - hand torque curve to obtain a return torque state; a return torque debugging module, configured to adjust the return coefficient - hand torque curve according to the return torque state to complete the return torque debugging of the electric power steering system; a return speed analysis module, configured to perform return speed analysis on the steering wheel angle - return coefficient curve to determine a return speed state; and a return speed debugging module, configured to adjust the return coefficient - hand torque curve according to the return speed state to complete the return speed debugging of the electric power steering system.

[0020] An embodiment of the third aspect of the present invention provides a vehicle, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the program to implement the steering return debugging method of the electric power steering system as described in the above embodiment.

[0021] An embodiment of the fourth aspect of the present invention provides a computer program product, where when the computer program / instructions are executed by a processor, the steering return debugging method of the electric power steering system as described above is implemented.

[0022] An embodiment of the fifth aspect of the present invention provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program, and when the program is executed by a processor, the steering return debugging method of the electric power steering system as described above is implemented.

[0023] The steering return debugging method and device of the electric power steering system proposed by the embodiments of the present invention can ensure that the vehicle maintains good return performance at various speeds through return torque debugging, reducing potential safety hazards caused by improper steering wheel operation; through return speed debugging, the return speed can be flexibly adjusted under different working conditions, making the return process of the steering wheel smoother and more stable, reducing the operation difficulty and fatigue of the driver during the steering process, improving the driver's control confidence and sense of security; by separately performing return torque debugging and return speed debugging, the handling performance and stability of the vehicle can be significantly improved, the driving experience can be optimized, and the safety during the vehicle driving process can be enhanced, which is also of great significance for improving the overall performance of the electric power steering system and meeting the control requirements of the driver.

[0024] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

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

[0026] Figure 1 It is a flowchart of a method for debugging the steering return of an electric power steering system provided by an embodiment of the present invention;

[0027] Figure 2 It is a schematic diagram of a return coefficient - hand torque curve provided by an embodiment of the present invention;

[0028] Figure 3 It is a schematic diagram of a lateral acceleration - hand torque curve provided by an embodiment of the present invention;

[0029] Figure 4 It is a schematic diagram of a steering wheel angle - return coefficient provided by an embodiment of the present invention;

[0030] Figure 5 It is a block schematic diagram of a device for debugging the steering return of an electric power steering system provided by an embodiment of the present invention;

[0031] Figure 6 It is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. Detailed Embodiments

[0032] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the 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 by referring to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0033] The steering return debugging and device of the electric power steering system according to an embodiment of the present invention will be described below with reference to the drawings.

[0034] Figure 1 It is a schematic flow diagram of a method for debugging the steering return of an electric power steering system provided by an embodiment of the present invention.

[0035] As Figure 1 shown, the method for debugging the steering return of the electric power steering system includes the following steps:

[0036] In step S101, the target vehicle is steered under low-speed conditions, at the intermediate position, and with large steering angles respectively, to establish the return coefficient - hand torque curve, lateral acceleration - hand torque curve, and steering wheel angle - return coefficient curve.

[0037] During the actual execution process, it is necessary to first conduct a steering return evaluation condition for the target vehicle, specifically as follows:

[0038] As Figure 2 shown, in the case of steering under low-speed conditions, drive at idling speed, 10 km / h, 15 km / h, 20 km / h, and 25 km / h respectively, slowly and evenly turn the steering wheel to the extreme angle, release the steering wheel, feel whether the return speed is consistent with the steering rhythm, release the steering wheel, and observe whether the steering wheel angle return speed is uniform, so as to collect the hand torque at each speed and its corresponding steering system frictional torque, and establish the return coefficient - hand torque curve based on the hand torque at each speed and its corresponding steering system frictional torque. Among them.

[0039] As Figure 3 shown, in the case of steering at the intermediate position, drive at 20 km / h, 40 km / h, 60 km / h, 80 km / h, 100 km / h, 120 km / h, and 140 km / h respectively, slowly and evenly turn the steering wheel left and right at a small angle, with the angle not exceeding ±15°, feel whether the return torque is appropriate and whether the return speed is slow and uniform (when returning, the steering wheel slides at the fingertips), so as to collect the hand torque at each speed and its corresponding lateral acceleration, and establish the lateral acceleration - hand torque curve based on the hand torque at each speed and its corresponding lateral acceleration.

[0040] As Figure 4 shown, in the case of steering with large angles, drive at 40 km / h, 60 km / h, 80 km / h, 100 km / h, and 120 km / h respectively, slowly and evenly turn the steering wheel left and right at a large angle, with the angle of ±20 to ±180°. The higher the vehicle speed, the smaller the angle. The specific angle is judged according to the handling stability of the vehicle. Feel whether the return torque is appropriate, whether the torque drops too quickly when returning to the intermediate position, and whether the return speed is slow and uniform, so as to collect the steering wheel angle at each speed and its corresponding steering wheel angle rate, and establish the lateral acceleration - hand torque curve based on the steering wheel angle at each speed and its corresponding steering wheel angle rate.

[0041] In step S102, the return torque analysis is carried out on the lateral acceleration - hand torque curve to obtain the return torque state.

[0042] In step S103, the return coefficient - hand torque curve is adjusted according to the return torque state to complete the return torque debugging of the electric power steering system.

[0043] In some embodiments, the self-aligning torque state includes at least two of strong self-aligning torque in the central region, normal self-aligning torque in the central region, strong self-aligning torque at large steering angles, and normal self-aligning torque at large steering angles.

[0044] During the actual execution process, self-aligning not only affects the naturalness of steering but also affects the linearity of the steering force and the convergence of the steering wheel. Therefore, the debugging of self-aligning mainly includes self-aligning torque debugging and self-aligning speed debugging. Among them, when debugging the self-aligning torque, first determine the trend and coefficient range of the self-aligning coefficient-hand torque curve. As Figure 2 shown, the torque corresponding to the ordinate of the first point of the self-aligning coefficient-hand torque curve corresponds to the frictional torque of the steering system, generally taking a value of about 0.4 Nm, and the corresponding ordinate coefficient is about 0.95; the arc transition of the curve is opposite to the phase of the tire cornering stiffness, and the maximum value of the hand torque generally takes a value of 3.0 Nm, corresponding to the ordinate of 0 to 0.2; furthermore, when steering back, this data principle needs to be followed, and the steering force will be basically more uniform and linear.

[0045] Based on the above principles, the self-aligning torque debugging of the electric power steering system is carried out as follows:

[0046] Obtain the steering starting torque at different vehicle speeds from the lateral acceleration-hand torque curve, compare the steering starting torques at adjacent vehicle speeds in sequence to obtain multiple comparison results. If there is a situation where the result is greater than the preset value among the multiple comparison results, the self-aligning torque state is strong self-aligning torque in the central region, and weaken the self-aligning coefficient in the corresponding region of the self-aligning coefficient-hand torque curve until there is no situation where the result is greater than the preset value among the multiple comparison results. Otherwise, the self-aligning torque state is normal self-aligning torque in the central region, and there is no need to adjust the self-aligning coefficient-hand torque curve. For example, as Figure 3 the green circles in are the starting torques of steering, also known as the hysteresis values of the steering torque. If at different vehicle speeds, the value of the lower circle is smaller (greater than 0.3 Nm) than that of the upper circle, it means that the self-aligning torque in the central region is strong and needs to be weakened. Figure 2 the self-aligning coefficient corresponding to the middle position area of the whole vehicle until the feel and Figure 3 the self-aligning curve are normal. The hand torque range corresponding to the middle position area of the whole vehicle: 0 - 2.8 Nm, covering the vehicle speed range of 20 - 100 km / h.

[0047] Furthermore, determine whether there is a torque asymmetry area in the lateral acceleration-hand torque curve. If there is a torque asymmetry area, the self-aligning torque state is strong self-aligning torque at large steering angles, and weaken the hand torque in the corresponding region of the self-aligning coefficient-hand torque curve until there is no torque asymmetry area. Otherwise, the self-aligning torque state is normal self-aligning torque at large steering angles, and there is no need to adjust the self-aligning coefficient-hand torque curve. For example, if the self-aligning torque at large steering angles is strong (regardless of vehicle speed), that is, corresponding to Figure 3The torque in the dashed area of the blue box is asymmetric, and the absolute value of the negative value is relatively small, which needs to be adjusted. Figure 2 For the curve near the corresponding ordinate of 3.0 Nm, the torque coefficient in the dashed area of the blue box decreases. The specific adjustment range is judged according to the feeling of pulling back when the large steering angle returns to the straight position.

[0048] It should be noted that Figure 2 The more points the curve is divided into, the smoother the steering return adjustment is. Generally, 8 - 10 point coordinates are recommended.

[0049] In step S104, the return speed analysis is performed on the steering wheel angle - return coefficient curve to determine the return speed state.

[0050] In step S105, the return coefficient - hand torque curve is adjusted according to the return speed state to complete the return speed debugging of the electric power steering system.

[0051] In some embodiments, the return speed state includes at least one of fast return speed, slow return speed, and normal return speed.

[0052] During the actual execution process, after completing the return torque debugging, the return speed debugging of the electric power steering system is carried out. The specific process is as follows:

[0053] It should be noted that the return speed refers to the uniformity of the direction return speed, which is divided into normal steering and rapid steering. In the embodiments of the present invention, the normal steering is described, and the steering wheel angular velocity is 100 - 150° / s. The return problems caused by rapid steering can be solved by damping compensation and inertia compensation. As Figure 4 shown, different curves represent the return speed curve characteristics at different vehicle speeds. Generally, the highest vehicle speed is set at 80 km / h, and the return above 80 km / h is mainly ensured by Figure 2 the return module and the vehicle's own return.

[0054] [[ID=z9]]First, the return speed analysis is performed on the steering wheel angle - return coefficient curve to determine the return speed state. In the case where the return speed state is fast return speed, the return coefficient and hand torque in the corresponding area of the return coefficient - hand torque curve are weakened until the return speed and hand torque meet the target requirements; in the case where the return speed state is slow return speed, the return coefficient and hand torque in the corresponding area of the return coefficient - hand torque curve are increased until the return speed and hand torque meet the target requirements; in the case where the return speed state is normal return speed, the return coefficient - hand torque curve does not need to be adjusted. For example, as Figure 4As shown by the blue curve, a relatively large return speed is required for low-speed return. The larger the return coefficient value, when evaluating the return speed at different vehicle speeds and different steering wheel angles during the return speed debugging to determine the return speed state, if the return speed is insufficient, it is necessary to increase it; if the return is too fast, the return coefficient needs to be reduced. It should be noted that the return speed coefficient mainly affects the steering wheel return speed, and on the other hand, it also affects the steering wheel return torque, that is, increasing the return speed will correspondingly increase the response steering wheel return torque. Therefore, it is necessary to cooperate with Figure 2 the return torque module for comprehensive debugging until the steering wheel return speed and return torque meet the subjective and objective target requirements.

[0055] In summary, according to the steering return debugging method of the electric power steering system proposed in the embodiments of the present invention, the following beneficial effects are obtained:

[0056] (1) Through the return torque debugging, it can ensure that the vehicle can maintain good return performance at various speeds, and reduce potential safety hazards caused by improper steering wheel operation;

[0057] (2) Through the return speed debugging, the return speed can be flexibly adjusted under different working conditions, making the return process of the steering wheel smoother and more stable, reducing the operation difficulty and fatigue of the driver during the steering process, and improving the driver's control confidence and sense of security;

[0058] (3) By separately performing the return torque debugging and the return speed debugging, it can significantly improve the vehicle's handling performance and stability, optimize the driving experience, and enhance the safety during the vehicle driving process, which is also of great significance for improving the overall performance of the electric power steering system and meeting the driver's control requirements.

[0059] Secondly, the steering return debugging device of the electric power steering system proposed in the embodiments of the present invention is described with reference to the accompanying drawings.

[0060] Figure 5 It is a block diagram of a steering return debugging device of an electric power steering system provided by an embodiment of the present invention.

[0061] As Figure 5 shown, the steering return debugging device 50 of the electric power steering system includes: a curve establishment module 501, a return torque analysis module 502, a return torque debugging module 503, a return speed analysis module 504, and a return speed debugging module 505.

[0062] Among them, the curve establishment module 501 is used to perform low-speed steering, middle-position steering, and large-angle steering on the target vehicle respectively to establish a return coefficient - hand torque curve, a lateral acceleration - hand torque curve, and a steering wheel angle - return coefficient curve. The return torque analysis module 502 is used to analyze the return torque of the lateral acceleration - hand torque curve to obtain the return torque state. The return torque debugging module 503 is used to adjust the return coefficient - hand torque curve according to the return torque state to complete the return torque debugging of the electric power steering system. The return speed analysis module 504 is used to analyze the return speed of the steering wheel angle - return coefficient curve to determine the return speed state. The return speed debugging module 505 is used to adjust the return coefficient - hand torque curve according to the return speed state to complete the return speed debugging of the electric power steering system.

[0063] In some embodiments, the return torque state includes at least two of strong return torque in the central region, normal return torque in the central region, strong return torque at large angles, and normal return torque at large angles.

[0064] In some embodiments, the return speed state includes at least one of fast return speed, slow return speed, and normal return speed.

[0065] In some embodiments, the return torque analysis module 502 includes:

[0066] An acquisition subunit, configured to acquire the steering starting torque at different vehicle speeds in the lateral acceleration - hand torque curve;

[0067] A first judgment subunit, configured to sequentially compare the steering starting torques at adjacent vehicle speeds to obtain a plurality of comparison results. If there is a case where the comparison results are greater than a preset value, the return torque state is strong return torque in the central region; otherwise, the return torque state is normal return torque in the central region;

[0068] A second judgment subunit, configured to determine whether there is a torque asymmetry region in the lateral acceleration - hand torque curve. If there is a torque asymmetry region, the return torque state is strong return torque at large angles; otherwise, the return torque state is normal return torque at large angles.

[0069] In some embodiments, the return torque debugging module 503 includes:

[0070] A debugging return coefficient subunit, in the case where the return torque state is strong return torque in the central region, weakening the return coefficient of the corresponding region in the return coefficient - hand torque curve until there is no case where the comparison results are greater than a preset value;

[0071] The debugging hand torque sub-unit is used to weaken the hand torque in the corresponding area of the return coefficient - hand torque curve until there is no torque asymmetry area when the return torque state is a large-angle return torque being strong;

[0072] The first non-debugging sub-unit is used to not adjust the return coefficient - hand torque curve when the return torque state is normal in the central area or normal in the large-angle return torque.

[0073] In some embodiments, the return speed debugging module 505 includes:

[0074] The first debugging return coefficient and hand torque sub-unit is used to weaken the return coefficient and hand torque in the corresponding area of the return coefficient - hand torque curve until the return speed and hand torque meet the target requirements when the return speed state is a fast return speed;

[0075] The second debugging return coefficient and hand torque sub-unit is used to increase the return coefficient and hand torque in the corresponding area of the return coefficient - hand torque curve until the return speed and hand torque meet the target requirements when the return speed state is a slow return speed;

[0076] The second non-debugging sub-unit is used to not adjust the return coefficient - hand torque curve when the return speed state is a normal return speed.

[0077] It should be noted that the foregoing explanation of the embodiments of the steering return debugging method for the electric power steering system also applies to the steering return debugging device of the electric power steering system in this embodiment, and will not be elaborated here.

[0078] The steering return debugging device of the electric power steering system according to the embodiment of the present invention has the following beneficial effects:

[0079] (1) Through the return torque debugging, it can ensure that the vehicle can maintain good return performance at various speeds, and reduce potential safety hazards caused by improper steering wheel operation;

[0080] (2) Through the return speed debugging, it can flexibly adjust the return speed under different working conditions, make the return process of the steering wheel smoother and more stable, reduce the operation difficulty and fatigue of the driver during the steering process, and improve the driver's control confidence and sense of security;

[0081] (3) By separately performing the return torque debugging and the return speed debugging, it can significantly improve the vehicle's handling performance and stability, optimize the driving experience, and enhance the safety during the vehicle driving process, which is also of great significance for improving the overall performance of the electric power steering system and meeting the driver's control requirements.

[0082] Figure 6A schematic structural diagram of a vehicle provided by an embodiment of the present invention. The vehicle may include:

[0083] A memory 601, a processor 602, and a computer program stored on the memory 601 and executable on the processor 602.

[0084] When the processor 602 executes the program, it implements the steering return adjustment method of the electric power steering system provided in the above embodiment.

[0085] Furthermore, the electronic device further includes:

[0086] A communication interface 603 for communication between the memory 601 and the processor 602.

[0087] The memory 601 is used to store a computer program executable on the processor 602.

[0088] The memory 601 may include a high-speed RAM memory, and may also include non-volatile memory, such as at least one disk memory.

[0089] If the memory 601, the processor 602, and the communication interface 603 are implemented independently, the communication interface 603, the memory 601, and the processor 602 can be interconnected through a bus and communicate with each other. The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 6 only a thick line is shown in the figure, but it does not mean that there is only one bus or one type of bus.

[0090] Optionally, in a specific implementation, if the memory 601, the processor 602, and the communication interface 603 are integrated on a chip, the memory 601, the processor 602, and the communication interface 603 can communicate with each other through an internal interface.

[0091] The processor 602 may be a Central Processing Unit (CPU), or an Application Specific Integrated Circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention.

[0092] An embodiment of the present invention also provides a computer program product. When the computer program / instructions are executed by a processor, the steering return debugging method of the electric power steering system as described above is implemented.

[0093] An embodiment of the present invention also provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the steering return debugging method of the electric power steering system as described above is implemented.

[0094] In the description of this specification, the descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0095] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0096] Any process or method description in the flowchart or described in other ways herein can be understood to represent a module, segment, or part of code including one or N executable instructions for implementing a customized logic function or process. The scope of the preferred embodiments of the present invention includes additional implementations, where the functions can be executed in a manner that may not be shown or discussed in the order shown, including in a substantially simultaneous manner according to the functions involved or in the reverse order, which should be understood by those skilled in the art of the embodiments of the present invention.

[0097] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or used in combination with these instruction execution systems, apparatus, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection part (electronic device) having one or N wirings, a portable computer disk cartridge (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then stored in a computer memory.

[0098] It should be understood that various parts of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, any one or a combination of the following techniques known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having suitable combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0099] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the methods of the above-described embodiments can be completed by a program instructing relevant hardware, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0100] In addition, each functional unit in various embodiments of the present invention may be integrated into a processing module, may exist physically alone for each unit, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0101] The above-mentioned storage medium may be a read-only memory, a magnetic disk, an optical disc, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A steering return debugging method for an electric power steering system, characterized in that The following steps are involved: The target vehicle is subjected to low-speed steering, mid-position steering, and large-angle steering to establish curves representing the return coefficient versus hand torque, the lateral acceleration versus hand torque, and the steering wheel angle versus return coefficient. Performing a return torque analysis on the lateral acceleration-hand torque curve to obtain a return torque state; Adjusting the return coefficient-hand torque curve according to the return torque state to complete the return torque debugging of the electric power steering system; Performing a return speed analysis on the steering wheel angle-return coefficient curve to determine a return speed state; The return coefficient-hand torque curve is adjusted according to the return speed state to complete the return speed debugging of the electric power steering system.

2. The steering return adjustment method of the electric power steering system according to claim 1, wherein The return torque state includes at least two of: a strong return torque in the center area, a normal return torque in the center area, a strong return torque at a large rotation angle, and a normal return torque at a large rotation angle.

3. The steering return adjustment method of the electric power steering system according to claim 1, wherein The return speed state includes at least one of a fast return speed, a slow return speed, and a normal return speed.

4. The steering return adjustment method for an electric power steering system according to claim 1, characterized in that The performing a return torque analysis on the lateral acceleration-hand torque curve to obtain a return torque state includes: Obtaining the steering starting torque at different vehicle speeds from the lateral acceleration-hand torque curve; The steering start torques at adjacent vehicle speeds are sequentially compared to obtain a plurality of comparison results. If any of the plurality of comparison results is greater than a preset value, the return torque state is a strong return torque in the center region; otherwise, the return torque state is a normal return torque in the center region. Determine whether there is a torque asymmetry region in the lateral acceleration-hand torque curve. If the torque asymmetry region exists, the return torque state is a large-angle return torque with a strong return torque. Otherwise, the return torque state is a large-angle return torque with a normal return torque.

5. The steering return adjustment method of the electric power steering system according to claim 1, characterized in that, The adjusting the return coefficient-hand torque curve according to the return torque state to complete the return torque debugging of the electric power steering system includes: When the return torque state is that the return torque in the central area is strong, the return coefficient of the corresponding area in the return coefficient-hand torque curve is weakened until there is no case where the return torque is greater than the preset value in multiple comparison results; When the return torque state is a large rotation angle with a strong return torque, the hand torque in the corresponding area of the return coefficient-hand torque curve is weakened until the torque asymmetry area no longer exists; When the return torque state is that the return torque in the center area is normal or the return torque in the large rotation angle is normal, there is no need to adjust the return coefficient-hand torque curve.

6. The steering return adjustment method for an electric power steering system according to claim 1, wherein The adjusting the return coefficient-hand torque curve according to the return speed state to complete the return speed debugging of the electric power steering system includes: When the return speed state is a fast return speed, the return coefficient and the hand torque in the corresponding area of the return coefficient-hand torque curve are weakened until the return speed and the hand torque meet the target requirements; When the return speed state is slow, increasing the return coefficient and hand torque in the corresponding area of the return coefficient-hand torque curve until the return speed and hand torque meet the target requirements; When the return speed state is normal, there is no need to adjust the return coefficient-hand torque curve.

7. A steering return debugging device for an electric power steering system, characterized in that, include: A curve module is established to perform low-speed steering, mid-position steering, and large-angle steering on the target vehicle, thereby establishing a return-to-centering coefficient-hand torque curve, a lateral acceleration-hand torque curve, and a steering wheel angle-return-to-centering coefficient curve. a return torque analysis module, configured to perform a return torque analysis on the lateral acceleration-hand torque curve to obtain a return torque state; a return torque debugging module, configured to adjust the return coefficient-hand torque curve according to the return torque state, so as to complete the return torque debugging of the electric power steering system; a return speed analysis module, configured to perform a return speed analysis on the steering wheel angle-return coefficient curve to determine a return speed state; The return speed debugging module is used to adjust the return coefficient-hand torque curve according to the return speed state to complete the return speed debugging of the electric power steering system.

8. A vehicle, characterized in that, include: 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 steering return debugging method of the electric power steering system according to any one of claims 1 to 6.

9. A computer program product, characterized in that, When the computer program / instruction is executed by a processor, the steering return debugging method of the electric power steering system according to any one of claims 1 to 6 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by a processor to implement the steering return debugging method of the electric power steering system according to any one of claims 1 to 6.

Images