Friction compensation methods, devices, equipment and vehicles for steer-by-wire systems

Abstract

This application provides a friction compensation method, apparatus, device, and vehicle for a steer-by-wire system. It relates to the technical field of vehicle steering systems. The method includes: acquiring the dynamic friction torque of the steering wheel, whereby the dynamic friction torque is the friction torque that causes the steering wheel to rotate at a constant speed when the vehicle is in a target state, such as a power-on synchronization state or a power-off return-to-center state; then, generating a friction torque curve representing the correspondence between the friction torque and the steering wheel speed based on at least one steering wheel rotation speed, at least one static friction torque, and the dynamic friction torque over a historical period; and performing friction compensation on the output torque of the road feel motor based on the friction torque curve. This method is used to adapt to changes in friction under different driving conditions to ensure that the driver always obtains a consistent and excellent steering feel, thereby improving the overall driving experience.

Description

Technical Field

[0001] This application relates to the field of vehicle steering system technology, and in particular to a friction compensation method, device, equipment and vehicle for a steer-by-wire system. Background Technology

[0002] With the rapid development of the automotive industry, the trends of vehicle intelligence and electrification are becoming increasingly prominent. As one of the key technologies in this field, steer-by-wire systems are gradually replacing traditional mechanical steering systems. Steer-by-wire systems control the steering angle of the wheels through electronic signals and electric actuators, eliminating the direct mechanical connection between the steering wheel and the wheels, thereby greatly improving the flexibility and safety of vehicle handling.

[0003] While steer-by-wire systems offer significant advantages in enhancing vehicle performance, their implementation relies on the precise coordination of electronic and mechanical components. In this process, friction becomes a crucial factor. In existing technologies, steer-by-wire systems typically employ preset, fixed friction torque compensation values ​​to counteract the effects of friction.

[0004] However, since friction can change due to factors such as wear and tear on parts and temperature variations, using a fixed friction torque compensation value often results in inconsistent steering feel for the driver, thus affecting the overall driving experience. Summary of the Invention

[0005] This application provides a friction compensation method, device, equipment, and vehicle for a steer-by-wire system, which improves the inconsistent feel of the driver when steering, thereby enhancing the overall driving experience.

[0006] In a first aspect, this application provides a friction compensation method for a steer-by-wire system, comprising:

[0007] The dynamic friction torque of the steering wheel is obtained. The dynamic friction torque is the friction torque that causes the steering wheel to rotate at a constant speed when the vehicle is in a target state. The target state includes the power-on synchronization state or the power-off return-to-center state.

[0008] A friction torque curve is generated based on at least one steering wheel rotation speed, at least one static friction torque, and the dynamic friction torque of the vehicle during a historical period. The friction torque curve is used to represent the correspondence between friction torque and steering wheel rotation speed.

[0009] Friction compensation is performed on the output torque of the road feel motor based on the aforementioned friction torque curve.

[0010] In one possible implementation, the friction compensation of the output torque of the road feeler motor based on the friction torque curve includes:

[0011] The initial friction torque is determined by querying the friction torque curve based on the current steering wheel speed of the vehicle.

[0012] The target friction torque is calculated based on the vehicle's current speed, the steering wheel's current steering torque, and the initial friction torque.

[0013] Friction compensation is performed on the output torque of the road sensor motor based on the target friction torque.

[0014] In one possible implementation, calculating the target friction torque based on the vehicle's current speed, the steering wheel's current steering torque, and the initial friction torque includes:

[0015] Based on the current vehicle speed, a first friction coefficient corresponding to the current vehicle speed is determined through a first mapping relationship, wherein the first mapping relationship is used to indicate the correspondence between vehicle speed and the first friction coefficient;

[0016] Based on the current steering torque of the steering wheel, a second friction coefficient corresponding to the current steering torque is determined through a second mapping relationship, wherein the second mapping relationship is used to indicate the correspondence between the steering torque and the second friction coefficient;

[0017] The product of the first friction coefficient, the second friction coefficient, and the initial friction torque is determined as the target friction torque.

[0018] In one possible implementation, the method further includes:

[0019] Based on the pre-selected power steering level, the target friction torque is optimized to obtain the optimized target friction torque;

[0020] Accordingly, the step of performing friction compensation on the output torque of the road sensor motor based on the target friction torque includes:

[0021] Friction compensation is performed on the output torque of the road sensor motor based on the optimized target friction torque.

[0022] In one possible implementation, obtaining the dynamic friction torque of the steering wheel includes:

[0023] The torque applied to the steering wheel is adjusted according to a pre-set torque curve, and the steering wheel speed is detected.

[0024] When the steering wheel reaches a uniform rotation speed and the rotation speed is stable, the dynamic friction torque is obtained based on the torque applied to the steering wheel.

[0025] In one possible implementation, obtaining the dynamic friction torque based on the torque applied to the steering wheel includes:

[0026] When the number of effective torques applied to the steering wheel reaches a preset number, the average value of all effective torques is determined as the candidate dynamic friction torque. The effective torques include the torques applied when the steering wheel is rotating at a constant speed and the rotation speed is stable.

[0027] If the candidate dynamic friction torque is greater than a first preset threshold and less than a second preset threshold, then the candidate dynamic friction torque is determined as the dynamic friction torque.

[0028] If the candidate dynamic friction torque is equal to the first preset threshold or equal to the second preset threshold, then the candidate dynamic friction torque is determined as the dynamic friction torque;

[0029] The first preset threshold is less than the second preset threshold.

[0030] In one possible implementation, the method further includes:

[0031] If the candidate dynamic friction torque is less than the first preset threshold or greater than the second preset threshold, then the dynamic friction torque result of the vehicle in the previous initial state is determined as the dynamic friction torque.

[0032] Secondly, this application provides a friction compensation device for a steer-by-wire system, comprising:

[0033] The first processing module is used to acquire the dynamic friction torque of the steering wheel. The dynamic friction torque is the friction torque that causes the steering wheel to rotate at a constant speed when the vehicle is in a target state. The target state includes the power-on synchronization state or the power-off return-to-center state.

[0034] The second processing module is used to generate a friction torque curve based on at least one steering wheel rotation speed, at least one static friction torque, and the dynamic friction torque of the vehicle during a historical period. The friction torque curve is used to represent the correspondence between friction torque and steering wheel rotation speed.

[0035] The control module is used to perform friction compensation on the output torque of the road feel motor based on the friction torque curve.

[0036] In one possible implementation, the control module is specifically used for:

[0037] The initial friction torque is determined by querying the friction torque curve based on the current steering wheel speed of the vehicle.

[0038] The target friction torque is calculated based on the vehicle's current speed, the steering wheel's current steering torque, and the initial friction torque.

[0039] Friction compensation is performed on the output torque of the road sensor motor based on the target friction torque.

[0040] In one possible implementation, the control module is specifically used for:

[0041] Based on the current vehicle speed, a first friction coefficient corresponding to the current vehicle speed is determined through a first mapping relationship, wherein the first mapping relationship is used to indicate the correspondence between vehicle speed and the first friction coefficient;

[0042] Based on the current steering torque of the steering wheel, a second friction coefficient corresponding to the current steering torque is determined through a second mapping relationship, wherein the second mapping relationship is used to indicate the correspondence between the steering torque and the second friction coefficient;

[0043] The product of the first friction coefficient, the second friction coefficient, and the initial friction torque is determined as the target friction torque.

[0044] In one possible implementation, the second processing module is further configured to:

[0045] Based on the pre-selected power steering level, the target friction torque is optimized to obtain the optimized target friction torque;

[0046] Accordingly, the control module is specifically used for:

[0047] Friction compensation is performed on the output torque of the road sensor motor based on the optimized target friction torque.

[0048] In one possible implementation, the first processing module is specifically used for:

[0049] The torque applied to the steering wheel is adjusted according to a pre-set torque curve, and the steering wheel speed is detected.

[0050] When the steering wheel reaches a uniform rotation speed and the rotation speed is stable, the dynamic friction torque is obtained based on the torque applied to the steering wheel.

[0051] In one possible implementation, the first processing module is specifically used for:

[0052] When the number of effective torques applied to the steering wheel reaches a preset number, the average value of all effective torques is determined as the candidate dynamic friction torque. The effective torques include the torques applied when the steering wheel is rotating at a constant speed and the rotation speed is stable.

[0053] If the candidate dynamic friction torque is greater than a first preset threshold and less than a second preset threshold, then the candidate dynamic friction torque is determined as the dynamic friction torque.

[0054] If the candidate dynamic friction torque is equal to the first preset threshold or equal to the second preset threshold, then the candidate dynamic friction torque is determined as the dynamic friction torque;

[0055] The first preset threshold is less than the second preset threshold.

[0056] In one possible implementation, the first processing module is further configured to:

[0057] If the candidate dynamic friction torque is less than the first preset threshold or greater than the second preset threshold, then the dynamic friction torque result of the vehicle in the previous initial state is determined as the dynamic friction torque.

[0058] Thirdly, this application provides an electronic device, including: a processor and a memory;

[0059] The memory stores computer-executed instructions;

[0060] The processor executes computer execution instructions stored in the memory, causing the processor to perform a friction compensation method for a steer-by-wire system as described in any of the first aspects.

[0061] Fourthly, this application provides a vehicle, including: a vehicle body and the electronic equipment described in the third aspect.

[0062] Fifthly, this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the friction compensation method of the steer-by-wire system according to any one of the first aspects.

[0063] Sixthly, this application provides a computer program product, the computer program product including a computer program, which, when executed by a processor, is used to implement the friction compensation method of the steer-by-wire system according to any one of the first aspects.

[0064] The friction compensation method, apparatus, device, and vehicle for a steer-by-wire system provided in this application include acquiring the dynamic friction torque of the steering wheel, generating a friction torque curve based on at least one steering wheel rotation speed, at least one static friction torque, and the dynamic friction torque over a historical period, and performing friction compensation on the output torque of the road feel motor based on the friction torque curve. In this process, by utilizing the friction torque curve generated from the dynamic friction torque, friction compensation can be performed on the output torque of the road feel motor, thereby enhancing the adaptability of the steer-by-wire system in various usage scenarios, eliminating inconsistent feel experienced by the driver during steering, and thus improving the overall driving experience. Attached Figure Description

[0065] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0066] Figure 1 A schematic diagram illustrating the application scenarios provided in the embodiments of this application;

[0067] Figure 2 A schematic flowchart of an embodiment of the friction compensation method for the steer-by-wire system provided in this application;

[0068] Figure 3 This is a schematic diagram of a structure for performing mechanical analysis on a steering wheel, provided in an embodiment of this application.

[0069] Figure 4 A schematic diagram of the friction torque curve provided in the embodiments of this application;

[0070] Figure 5 A schematic flowchart of Embodiment 2 of the friction compensation method for the steer-by-wire system provided in this application;

[0071] Figure 6 A schematic flowchart of Embodiment 3 of the friction compensation method for the steer-by-wire system provided in this application;

[0072] Figure 7 A schematic flowchart of Embodiment 4 of the friction compensation method for the steer-by-wire system provided in this application;

[0073] Figure 8 A flowchart illustrating an example of obtaining dynamic friction torque provided in this application embodiment;

[0074] Figure 9 A flowchart illustrating an example of a friction compensation method for a steer-by-wire system provided in this application embodiment;

[0075] Figure 10 A schematic diagram of the friction compensation device for the steer-by-wire system provided in this application embodiment;

[0076] Figure 11 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0077] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0078] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0079] First, let me explain the terms used in this application:

[0080] Power-on synchronization: This refers to the vehicle's electronic control unit checking and calibrating the steering wheel position when the vehicle is started or powered on, so that it is consistent with the actual steering angle of the wheels.

[0081] Power-off return to center: This refers to the vehicle's electronic control unit being able to control the steering wheel to return to a neutral or straight position when the vehicle's power is off or it enters a sleep state.

[0082] To meet the demands of intelligent driving development, the vehicle's steering system has adopted full steer-by-wire technology instead of the traditional mechanical steering system. This eliminates the mechanical connections between steering components, reduces spatial constraints on their arrangement, and provides a solid foundation for intelligent driving cockpit design. It also increases the possibilities for coordination between the steering system and other chassis systems.

[0083] Steer-by-wire (SBW) technology eliminates traditional mechanical connections, enabling electrical communication between the steering wheel and the steering actuator. This innovation significantly enhances vehicle handling agility and safety. However, while SBW systems offer substantial advantages in improving vehicle performance, their implementation still relies on the precise coordination of electronic and mechanical components. In this process, friction within the system becomes a significant factor.

[0084] In existing technologies, steer-by-wire systems typically use a preset fixed friction torque compensation value to counteract the effects of friction. However, since friction can vary due to factors such as component wear and temperature changes, using a fixed friction torque compensation value often results in inconsistent steering feel for the driver, thus affecting the overall driving experience.

[0085] To address the aforementioned issues, the inventors considered dynamically adjusting the friction compensation torque to meet the changing friction requirements under different driving conditions, thereby ensuring the driver receives a consistent and high-quality steering feel. Specifically, when the vehicle is in the target state, the dynamic friction torque that causes the steering wheel to rotate at a constant speed can be obtained. A friction torque curve is generated based on at least one steering wheel rotation speed, at least one static friction torque, and the dynamic friction torque causing the steering wheel to rotate at a constant speed over a historical period. Based on the friction torque curve, the output torque of the road feel motor is compensated, improving the adaptability of the steer-by-wire system in various usage scenarios, reducing inconsistent steering feel for the driver, and providing a better driving experience. Based on this, this application proposes a friction compensation method for a steer-by-wire system to address changes in steering wheel friction under different vehicle operating conditions, thereby improving the friction compensation effect, ensuring the driver receives a consistent and high-quality steering feel, and enhancing the driving experience.

[0086] Figure 1 This is a schematic diagram illustrating an application scenario provided in an embodiment of this application. Please refer to [link / reference]. Figure 1 The vehicle 100 is equipped with a road sensor motor 101 and a steering wheel 102. The road sensor motor 101 can provide varying frictional torque to effectively compensate for the frictional torque generated by the steering wheel 102 during rotation.

[0087] For example, as the driver turns the steering wheel 102, the road feel motor 101 can provide varying frictional torque to counteract the resistance generated by friction during the rotation of the steering wheel 102, thereby improving the driver's steering feel.

[0088] The technical solution of this application and how it solves the above-mentioned technical problems will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.

[0089] Figure 2 This is a schematic flowchart illustrating an embodiment of the friction compensation method for the steer-by-wire system provided in this application. Please refer to [link / reference]. Figure 2 The method includes:

[0090] S201. Obtain the dynamic friction torque of the steering wheel.

[0091] The execution subject in this application embodiment can be an electronic device or a friction compensation device of a steer-by-wire system installed in an electronic device. The friction compensation device of the steer-by-wire system can be implemented through software or a combination of software and hardware. The friction compensation device of the steer-by-wire system can be a processor in an electronic device. For ease of understanding, the following description will use an electronic device as the execution subject.

[0092] In this step, the electronic device can acquire the dynamic friction torque of the steering wheel, which is the friction torque that causes the steering wheel to rotate at a constant speed when the vehicle is in the target state. The target state includes either the power-on synchronization state or the power-off return-to-center state.

[0093] By selecting the power-on synchronization state or the power-off return state as the target state, seamless connection with the normal vehicle operation state can be achieved without the need for additional state monitoring logic, thus simplifying the complexity of the system.

[0094] Optionally, the functional status of the steering wheel can be determined. When it is determined that the steering wheel is in the power-on synchronization state or the power-off return-to-center state, the steering wheel speed can be set as a monitoring parameter. By increasing the torque input of the steering wheel through the road sensor motor, the change of real friction torque is simulated. When the steering wheel reaches a uniform rotation speed and the speed is stable, the dynamic friction torque is obtained based on the torque applied to the steering wheel.

[0095] Figure 3 This is a schematic diagram illustrating the structure for performing mechanical analysis on a steering wheel, as provided in an embodiment of this application. Please refer to... Figure 3 During the rotation of the steering wheel, it will be subjected to frictional force f, which in turn generates frictional torque Tf. The torque input to the steering wheel can be increased by the road sensor motor. When the steering wheel reaches a uniform rotation speed and the speed is stable, the torque TF applied to the steering wheel is determined as the dynamic frictional torque. At this time, the frictional torque Tf and the torque TF are the same in magnitude but opposite in direction.

[0096] For example, when the steering wheel is in the power-on synchronization state, the torque TF that makes the steering wheel rotate at a constant speed can be obtained.

[0097] S202. Generate a friction torque curve based on at least one steering wheel rotation speed, at least one static friction torque, and dynamic friction torque of the vehicle during a historical period.

[0098] In this step, after obtaining the dynamic friction torque, a friction torque curve representing the relationship between friction torque and steering wheel speed can be generated based on at least one steering wheel speed and at least one static friction torque of the vehicle during a historical period.

[0099] The historical time period can be the initial time period when the vehicle ends the target state and enters the normal driving state; or it can be a time period during the vehicle's historical driving process.

[0100] In one optional implementation, during the initial period, the driver can gradually increase the torque applied to the steering wheel. While the steering wheel is not actually rotating, an internal algorithm simulates at least one steering wheel rotation speed and the corresponding static friction torque for each steering wheel rotation speed. Then, the at least one steering wheel rotation speed, the corresponding static friction torque for each steering wheel rotation speed, and the dynamic friction torque can be calculated to generate a friction torque curve. The dynamic friction torque is also the maximum static friction torque.

[0101] In another alternative implementation, the historical time period is the time period during which the vehicle travels in history. In this case, a test experiment on the steering wheel speed and static friction torque can be conducted on the vehicle during the historical time period to determine at least one steering wheel speed and the static friction torque corresponding to each steering wheel speed. Then, a friction torque curve is generated based on at least one steering wheel speed, the static friction torque corresponding to each steering wheel speed, and the dynamic friction torque during the historical time period.

[0102] Specifically, the historical time period includes multiple smaller time periods. By conducting tests on steering wheel speed and static friction torque for each smaller time period, at least one steering wheel speed and its corresponding static friction torque within each time period can be determined. Then, the data from each time period can be comprehensively analyzed and processed, such as calculating the average value or performing cluster analysis, and combined with the dynamic friction torque to finally generate the overall friction torque curve.

[0103] Figure 4 This is a schematic diagram of the friction torque curve provided in an embodiment of this application. Please refer to... Figure 4 The horizontal axis of the torque curve represents the steering wheel speed, and the vertical axis represents the friction torque. TF represents the dynamic friction torque, which is also the maximum static friction torque.

[0104] It should be noted that when the driver turns the steering wheel, they can choose to turn left or right, so the vertical axis of the friction torque may be positive or negative. Specifically, turning the steering wheel to the right can be defined as the positive direction of the angle, and turning it to the left as the negative direction. In this case, the dynamic friction torque (the torque that causes the steering wheel to rotate) is positive when the steering wheel is turned to the right, and negative when turning it to the left.

[0105] S203. Based on the friction torque curve, perform friction compensation on the output torque of the road feel motor.

[0106] In this step, the output torque of the road sensor motor can be adjusted in real time according to the pre-generated friction torque curve during the steering wheel rotation, so as to achieve effective compensation for friction.

[0107] For example, when the driver turns the steering wheel, the electronic equipment can detect the current steering wheel speed and determine the corresponding friction torque value by referring to the friction torque curve. Then, the road sensor motor adjusts its output torque according to this friction torque value, thereby compensating for the steering wheel operating resistance caused by friction.

[0108] In this embodiment, the frictional torque that causes the steering wheel to rotate at a constant speed can be obtained when the steering wheel is in a power-on synchronization state or a power-off return-to-center state, serving as the dynamic frictional torque of the steering wheel. A frictional torque curve can be generated based on at least one steering wheel rotation speed, at least one static frictional torque, and the dynamic frictional torque within a historical time period. Based on the generated frictional torque curve, friction compensation is applied to the output torque of the road sensor motor. In this process, the dynamic frictional torque obtained when the steering wheel is in a power-on synchronization state or a power-off return-to-center state, combined with the steering wheel rotation speed and static frictional torque from historical data, generates a frictional torque curve. This curve is used to compensate for the friction of the road sensor motor's output torque, thereby improving the driver's steering feel and overall driving experience.

[0109] exist Figure 2 Based on the illustrated embodiment, the following, in conjunction with Figure 5 The friction compensation method for the above-mentioned steer-by-wire system will be further explained in detail.

[0110] Figure 5 This is a schematic flowchart illustrating a second embodiment of the friction compensation method for the steer-by-wire system provided in this application. Please refer to... Figure 5 The method may include:

[0111] S501. Adjust the torque applied to the steering wheel according to the preset torque curve, and detect the steering wheel speed.

[0112] In this step, when the vehicle is in the target state, the electronic device can adjust the torque applied to the steering wheel according to a pre-set torque curve via a road sensor motor, increasing or decreasing the torque input to the steering wheel, and detecting the steering wheel speed. The target state includes either the power-on synchronization state or the power-off return-to-center state.

[0113] Torque curves can be customized based on vehicle type and specifications. For example, different torque curves can be designed for different types of vehicles, such as cars and trucks, to meet their respective handling requirements.

[0114] The pre-set torque curve can be a progressive straight line starting from the origin and sloping upwards to the right, with a non-zero slope.

[0115] In one specific implementation, during the process of adjusting the torque applied to the steering wheel via a road-sensor motor based on a pre-set torque curve, an optimization adjustment algorithm can be incorporated to achieve precise torque control. This optimization adjustment algorithm can be a proportional-integral-derivative (PID) control algorithm. The specific optimization adjustment algorithm can be adjusted according to the actual scenario, and this application does not impose any specific limitations.

[0116] S502. When the steering wheel reaches a constant speed and the rotation speed is stable, obtain the dynamic friction torque based on the torque applied to the steering wheel.

[0117] For example, while adjusting the torque applied to the steering wheel, the electronic device can detect the steering wheel speed. When the steering wheel reaches a constant speed and the speed is stable, the torque applied to the steering wheel is determined as dynamic friction torque.

[0118] S503. Generate a friction torque curve based on at least one steering wheel rotation speed, at least one static friction torque, and dynamic friction torque of the vehicle during a historical period.

[0119] In one specific implementation, the historical time period can be the initial period when the vehicle ends the target state and enters the normal driving state. Since the time the driver turns the steering wheel is relatively short, a friction torque curve can be generated by measuring at least one steering wheel rotation speed, at least one static friction torque, and dynamic friction torque during the initial period, and this curve can be continuously used during subsequent driving.

[0120] S504. Based on the current steering wheel speed of the vehicle, query the friction torque curve to determine the initial friction torque.

[0121] In this step, during normal vehicle operation, the electronic device can query the friction torque curve based on the vehicle's current steering wheel rotation speed to determine the initial friction torque.

[0122] For example, during normal vehicle operation, electronic devices can query the friction torque curve based on the vehicle's current steering wheel rotation speed V1 to determine the initial friction torque T0.

[0123] S505. The target friction torque is calculated based on the vehicle's current speed, the current steering torque of the steering wheel, and the initial friction torque.

[0124] In this step, a first friction coefficient corresponding to the current vehicle speed is determined using a first mapping relationship, and a second friction coefficient corresponding to the current steering torque is determined using a second mapping relationship. The product of the first friction coefficient, the second friction coefficient, and the initial friction torque is then determined as the target friction torque. The first mapping relationship indicates the correspondence between vehicle speed and the first friction coefficient, while the second mapping relationship indicates the correspondence between steering torque and the second friction coefficient.

[0125] For example, based on the vehicle's current speed M1, the first friction coefficient a1 corresponding to the current speed can be determined through a first mapping relationship. Based on the current steering torque T1 of the steering wheel, the second friction coefficient b1 corresponding to the current steering torque can be determined through a second mapping relationship. The product of the first friction coefficient a1, the second friction coefficient b1, and the initial friction torque T0 is determined as the target friction torque.

[0126] In one alternative implementation, after obtaining the vehicle's current steering wheel rotation speed, current vehicle speed, and current steering torque, these parameters are filtered to eliminate noise and irregular fluctuations, thereby obtaining more stable and accurate data.

[0127] S506. Based on the target friction torque, perform friction compensation on the output torque of the road sensor motor.

[0128] In this step, the electronic device can adjust the output torque of the road sensor motor according to the target friction torque during the steering wheel rotation, so as to achieve effective compensation for friction.

[0129] In one alternative implementation, after determining the target friction torque, the target friction torque can be optimized according to the power steering level pre-selected by the driver to obtain an optimized target friction torque. Based on the optimized target friction torque, friction compensation is applied to the output torque of the road feel motor.

[0130] In practice, the target friction torque can be adjusted using a predefined mapping table or function based on the power steering level selected by the driver. Different power steering levels can correspond to different friction torque adjustment coefficients, thereby changing the steering feel of the steering wheel.

[0131] For example, in city driving, drivers may prefer to choose a higher power steering level, making the steering wheel lighter and easier to maneuver in narrow streets and parking lots. On the other hand, in highway driving, drivers may prefer a lower power steering level for better feel and stability.

[0132] In this embodiment, the torque applied to the steering wheel can be adjusted using a preset torque curve, and its rotational speed can be detected. When the steering wheel reaches a constant speed and the rotational speed is stable, the dynamic frictional torque is obtained based on the applied torque. A frictional torque curve is generated by combining at least one steering wheel rotational speed, at least one static frictional torque, and the dynamic frictional torque from a historical time period. By querying the frictional torque curve corresponding to the current steering wheel rotational speed, the initial frictional torque is determined. Then, based on the current vehicle speed, the current steering torque of the steering wheel, and the initial frictional torque, the target frictional torque is calculated, and friction compensation is applied to the output torque of the road sensor motor. In the above process, the frictional torque can be adaptively adjusted according to the steering wheel rotational speed, vehicle speed, and steering torque. Through this adaptive adjustment, the frictional torque can be dynamically optimized according to real-time driving conditions, ensuring that the driver receives a consistent feel when operating the steering wheel.

[0133] Furthermore, the friction compensation method for the steer-by-wire system provided in this application embodiment can adjust the target friction torque by setting a preset power steering level, allowing the driver to freely choose a suitable steering assist level according to personal preferences and driving environment. By optimizing the steering wheel's weight, the driver's operational burden can be reduced, and driving comfort can be improved.

[0134] Figure 6 This is a schematic flowchart illustrating Embodiment 3 of the friction compensation method for the steer-by-wire system provided in this application. Please refer to... Figure 6 Based on the above embodiments, in the specific implementation of the friction compensation method for the steer-by-wire system, step S505, which calculates the target friction torque based on the vehicle's current speed, the steering wheel's current steering torque, and the initial friction torque, further includes the following steps:

[0135] S601. Based on the vehicle's current speed, determine the first friction coefficient corresponding to the current speed through the first mapping relationship.

[0136] In this step, the first friction coefficient corresponding to the current vehicle speed can be determined based on the vehicle's current speed during driving, through a first mapping relationship that indicates the correspondence between vehicle speed and the first friction coefficient.

[0137] The vehicle's current speed can be obtained from the vehicle's speed sensor. For example, the speed sensor can determine that the vehicle's current speed is M1.

[0138] The first mapping relationship can be designed based on the vehicle's dynamic characteristics and driving safety requirements. Through experimental and testing methods, the first friction coefficient corresponding to different vehicle speeds can be collected to establish the first mapping relationship.

[0139] For example, the first mapping relationship can be represented by Table 1:

[0140] Table 1

[0141] 0＜M≤10 0.3 40＜M≤50 0.7 10＜M≤20 0.4 50＜M≤60 0.8 20＜M≤30 0.5 60＜M≤70 0.9 30＜M≤40 0.6 70＜M≤80 1

[0142] By dividing the vehicle speed into different intervals and assigning a corresponding first friction coefficient to each interval, the correspondence between vehicle speed and the first friction coefficient is realized.

[0143] For example, based on the vehicle's current speed V1 being 30 km / h, the first friction coefficient corresponding to the current speed of 30 km / h can be determined to be 0.5 through the first mapping relationship.

[0144] S602. Based on the current steering torque of the steering wheel, determine the second friction coefficient corresponding to the current steering torque through the second mapping relationship.

[0145] In this step, the second friction coefficient corresponding to the current steering torque can be determined based on the current steering torque of the vehicle during driving, through a second mapping relationship used to indicate the correspondence between the steering torque and the second friction coefficient.

[0146] The current steering torque of a vehicle can be obtained from a torque sensor installed in the vehicle. Specifically, a torque sensor can be installed on the rotating shaft connected to the steering wheel. By measuring the torsional deformation of the rotating shaft under torque, the torque applied to the rotating shaft can be calculated, thus obtaining the vehicle's current steering torque. For example, the current steering torque of the vehicle can be obtained as T1 using a torque sensor.

[0147] Similarly, the second mapping relationship can be designed based on the vehicle's dynamic characteristics and driving safety requirements. Through experimental and testing methods, the second friction coefficient corresponding to different steering torques is collected, thereby establishing the second mapping relationship.

[0148] For example, based on the vehicle's current steering torque T1 being 100 N·m, the second friction coefficient corresponding to the current steering torque of 100 N·m can be determined to be 0.6 through the second mapping relationship.

[0149] S603. The product of the first friction coefficient, the second friction coefficient, and the initial friction torque is determined as the target friction torque.

[0150] For example, if the initial friction torque is determined to be 300 N·m by consulting the friction torque curve based on the vehicle's current steering wheel speed, then the target friction torque of 90 N·m can be determined by using the first friction coefficient of 0.5, the second friction coefficient of 0.6, and the initial friction torque of 300 N·m.

[0151] In this embodiment, a first friction coefficient can be determined based on the vehicle's current speed using a first mapping relationship; a second friction coefficient can be determined based on the steering wheel's current steering torque using a second mapping relationship; and the first and second friction coefficients are multiplied by the initial friction torque to determine the target friction torque. In this process, the friction coefficient can be precisely adjusted according to the vehicle's current speed and the steering wheel's steering torque, thereby providing a more natural and linear steering feel, ensuring consistent feedback from the steering wheel under various driving conditions, and enhancing the driver's driving experience.

[0152] Figure 7 This is a schematic flowchart illustrating Embodiment 4 of the friction compensation method for the steer-by-wire system provided in this application. Please refer to... Figure 7 Based on the above embodiments, in the specific implementation of the friction compensation method for the steer-by-wire system, step S502, which involves obtaining the dynamic friction torque based on the torque applied to the steering wheel, further includes the following steps:

[0153] S701. When the number of effective torques applied to the steering wheel reaches a preset number, the average value of all effective torques is determined as the candidate dynamic friction torque.

[0154] In this step, when the steering wheel is rotating at a constant speed and the rotation speed is stable, the torque applied to the steering wheel can be recorded as an effective torque. When the number of recorded effective torques reaches a preset number, the average of all recorded effective torques can be calculated, and the calculation result can be determined as the candidate dynamic friction torque.

[0155] Optionally, in the process of adjusting the torque applied to the steering wheel according to the preset torque curve, in order to prevent sudden changes in the torque output by the road sensor motor, a preset number of effective torques can be used for smoothing. By averaging multiple recorded effective torques, large deviations in the determined dynamic friction torque caused by sudden torque changes can be avoided.

[0156] For example, if the preset number is 3, and the steering wheel is rotating at a constant speed and the speed is stable, when the number of effective torques applied to the steering wheel reaches 3, the 3 effective torques are 49 N·m, 50 N·m, and 51 N·m, respectively. Then the average value of the 3 effective torques, 50 N·m, can be determined as the candidate dynamic friction torque.

[0157] S702. If the dynamic friction torque to be selected is greater than the first preset threshold and less than the second preset threshold, then the dynamic friction torque to be selected is determined as the dynamic friction torque.

[0158] In this step, after determining the candidate dynamic friction torque, a range verification can be performed. If the candidate dynamic friction torque is greater than a first preset threshold and less than a second preset threshold, it is determined as the dynamic friction torque. The first preset threshold is less than the second preset threshold.

[0159] For example, if the first preset threshold is 40 N·m and the second preset threshold is 60 N·m, then the selected dynamic friction torque is determined to be 50 N·m, which is greater than the first preset threshold of 40 N·m and less than the second preset threshold of 60 N·m. Therefore, the selected dynamic friction torque of 50 N·m is determined as the dynamic friction torque.

[0160] S703. If the dynamic friction torque to be selected is equal to the first preset threshold or equal to the second preset threshold, then the dynamic friction torque to be selected is determined as the dynamic friction torque.

[0161] In this step, after determining the candidate dynamic friction torque, the range of the candidate dynamic friction torque can be further verified. If the candidate dynamic friction torque is equal to the first preset threshold or equal to the second preset threshold, the candidate dynamic friction torque is determined as the dynamic friction torque.

[0162] For example, if the first preset threshold is 40 N·m and the second preset threshold is 60 N·m, and the selected dynamic friction torque is 40 N·m, which is equal to the first preset threshold of 40 N·m, then the selected dynamic friction torque of 40 N·m is determined as the dynamic friction torque.

[0163] S704. If the dynamic friction torque to be selected is less than the first preset threshold or greater than the second preset threshold, then the dynamic friction torque result of the vehicle in the previous initial state shall be determined as the dynamic friction torque.

[0164] In this step, after determining the candidate dynamic friction torque, the dynamic friction torque result of the vehicle in the previous initial state can be determined as the dynamic friction torque if it is less than the first preset threshold or greater than the second preset threshold.

[0165] For example, if the first preset threshold is 40 N·m and the second preset threshold is 60 N·m, and the determined dynamic friction torque is 70 N·m, which is greater than the second preset threshold of 60 N·m, then the dynamic friction torque result of 55 N·m in the previous initial state of the vehicle is determined as the dynamic friction torque.

[0166] In this embodiment, when the number of effective torques applied to the steering wheel reaches a preset number, their average value is calculated as the candidate dynamic friction torque. If the average value is between a first preset threshold and a second preset threshold, or equal to either threshold, it is determined as the dynamic friction torque. Otherwise, the dynamic friction torque result of the vehicle's previous initial state is used as the current dynamic friction torque. In the above process, by using a threshold judgment on the average value of the effective torque, the stability and reliability of the dynamic friction torque are ensured. Even in abnormal situations, the use of the dynamic friction torque from the previous state can prevent sudden changes in steering feel, thereby ensuring that the driver always receives a stable and reliable vehicle response.

[0167] Figure 8 This is a schematic flowchart illustrating an example of obtaining dynamic friction torque according to an embodiment of this application. Please refer to... Figure 8 This includes the following steps:

[0168] S801, Steering wheel function status judgment.

[0169] Optionally, the electronic devices can check the vehicle's main state to ensure that the current vehicle (also the steering wheel) is in a target state. This target state includes either power-on synchronization or power-off return to center.

[0170] S802. Determine whether the vehicle is in the power-on synchronization state or the power-off return state.

[0171] S803, triggers the friction self-learning function.

[0172] In this step, once the steering wheel is determined to be in a state of power-on synchronization or power-off return to center, the friction self-learning function can be activated. At this time, the steering wheel speed can be included as a parameter in the monitoring range for torque adjustment.

[0173] Alternatively, in addition to using the steering wheel's rotation speed as a monitoring parameter, the steering wheel's angle can also be included as an observation value in the monitoring range. The rotation speed indicates the rate of steering wheel rotation, while the angle indicates its current position. Combining these two parameters provides more comprehensive steering status information.

[0174] S804, Increase the torque input of the steering wheel.

[0175] Optionally, the torque applied to the steering wheel can be adjusted according to a pre-set torque curve to simulate changes in real friction torque.

[0176] S805. Determine if the steering wheel has reached the condition of uniform rotation (speed V). T = Rotational speed V T-1 ).

[0177] Optionally, the steering wheel's rotation status can be monitored in real time, and the system can determine when the steering wheel is rotating at a constant speed, i.e., the current rotational speed V. T Equal to the rotational speed V at the previous moment T-1 At that moment, the torque applied to the steering wheel at the current moment is recorded as the effective torque.

[0178] S806. Record the effective torque and increment the count by 1.

[0179] Optionally, a counter set in the electronic device can be automatically incremented by 1 each time an effective torque is recorded.

[0180] S807. Record whether the number of torques has reached the preset number.

[0181] For example, if the preset number is 5, step S808 can be executed when the number of recorded effective torques reaches 5.

[0182] S808. Calculate the mean value to obtain the dynamic friction torque to be selected.

[0183] For example, the average value of all effective torques can be calculated to obtain the friction self-learning torque value that reflects the true friction characteristics of the steering wheel under specific conditions, i.e., the dynamic friction torque to be selected.

[0184] Optionally, the dynamic friction torque to be selected can also be obtained by interpolation calculation. The interpolation calculation can also include any one of linear interpolation, polynomial interpolation, and spline interpolation. Those skilled in the art can choose according to actual needs.

[0185] S809. Is the dynamic friction torque to be selected between the preset minimum threshold and the maximum threshold?

[0186] If yes, then execute S810; otherwise, execute S811.

[0187] S810 outputs dynamic friction torque.

[0188] For example, a candidate dynamic friction torque can be determined as a dynamic friction torque based on the following conditions: the candidate dynamic friction torque is greater than a first preset threshold and less than a second preset threshold; or the candidate dynamic friction torque is equal to the first preset threshold; or the candidate dynamic friction torque is equal to the second preset threshold. The first preset threshold can be a preset minimum threshold, and the second preset threshold can be a preset maximum threshold.

[0189] S811, outputs the dynamic friction torque of the previous time.

[0190] For example, the dynamic friction torque result of the vehicle in the previous initial state can be determined as the dynamic friction torque if the candidate dynamic friction torque is less than a first preset threshold or greater than a second preset threshold.

[0191] The example of obtaining dynamic friction torque provided in this embodiment can be referred to in the process shown in the above method embodiment. The implementation principle and beneficial effects are similar, and will not be repeated here.

[0192] Figure 9 This is a flowchart illustrating an example of a friction compensation method for a steer-by-wire system provided in this application. Please refer to... Figure 9 This includes the following steps:

[0193] S901, Signal preprocessing (low-pass filter).

[0194] Optionally, after obtaining the vehicle's current steering wheel speed, current vehicle speed, and current steering torque, a low-pass filter (LPF) can be used to filter these parameters to reduce noise interference and thus ensure the accuracy of the data.

[0195] S902, parameter simulation to determine the initial friction torque.

[0196] For example, a friction torque curve can be generated based on at least one steering wheel speed, at least one static friction torque, and dynamic friction torque of the vehicle during a historical period. The initial friction torque can be determined by querying the friction torque curve based on the vehicle's current steering wheel speed.

[0197] S903. Locate the vehicle speed-first friction coefficient table to determine the first friction coefficient.

[0198] For example, the first friction coefficient corresponding to the current vehicle speed can be determined through a first mapping relationship based on the current vehicle speed. The first mapping relationship is used to indicate the correspondence between vehicle speed and the first friction coefficient.

[0199] Specifically, the first mapping relationship can be represented by a vehicle speed-first friction coefficient table. This table can include multiple vehicle speeds and the corresponding first friction coefficient for each speed.

[0200] S904. Locate the torque-second friction coefficient table to determine the second friction coefficient.

[0201] For example, based on the current steering torque of the steering wheel, the second friction coefficient corresponding to the current steering torque can be determined through a second mapping relationship. The second mapping relationship is used to indicate the correspondence between the steering torque and the second friction coefficient.

[0202] Specifically, the second mapping relationship can be represented by a torque-second friction coefficient table. This table can include multiple torques and the corresponding second friction coefficient for each torque.

[0203] S905. Determine the target friction coefficient.

[0204] For example, the product of the first friction coefficient, the second friction coefficient, and the initial friction torque can be determined as the target friction torque.

[0205] S906, Select the power steering level.

[0206] Optionally, the driver can manually select the level of power assist through the in-vehicle control interface.

[0207] For example, when driving at low speeds or parking, the driver can choose a higher level of power steering to make the steering wheel lighter and easier to operate; when driving at high speeds, the driver can choose a lower level of power steering to increase the damping of the steering wheel and enhance the vehicle's stability and road feel.

[0208] S907, Obtain the optimized target friction torque.

[0209] Specifically, the target friction torque can be optimized based on the pre-selected power steering level to obtain the optimized target friction torque.

[0210] The friction compensation method for the steer-by-wire system provided in this embodiment is similar in principle and effect to the method embodiment described above, and will not be repeated here.

[0211] Figure 10 This is a schematic diagram of the friction compensation device for the steer-by-wire system provided in an embodiment of this application. Please refer to [link / reference]. Figure 10 The friction compensation device 10 of the steer-by-wire system includes:

[0212] The first processing module 11 is used to acquire the dynamic friction torque of the steering wheel. The dynamic friction torque is the friction torque that causes the steering wheel to rotate at a constant speed when the vehicle is in a target state. The target state includes the power-on synchronization state or the power-off return-to-center state.

[0213] The second processing module 12 is used to generate a friction torque curve based on at least one steering wheel rotation speed, at least one static friction torque, and the dynamic friction torque of the vehicle during a historical period. The friction torque curve is used to represent the correspondence between friction torque and steering wheel rotation speed.

[0214] Control module 13 is used to perform friction compensation on the output torque of the road feel motor based on the friction torque curve.

[0215] The friction compensation device for the steer-by-wire system provided in this application embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effect are similar, and will not be described again here.

[0216] In one possible implementation, the control module 13 is specifically used for:

[0217] The initial friction torque is determined by querying the friction torque curve based on the current steering wheel speed of the vehicle.

[0218] The target friction torque is calculated based on the vehicle's current speed, the steering wheel's current steering torque, and the initial friction torque.

[0219] Friction compensation is performed on the output torque of the road sensor motor based on the target friction torque.

[0220] In one possible implementation, the control module 13 is specifically used for:

[0221] Based on the current vehicle speed, a first friction coefficient corresponding to the current vehicle speed is determined through a first mapping relationship, wherein the first mapping relationship is used to indicate the correspondence between vehicle speed and the first friction coefficient;

[0222] Based on the current steering torque of the steering wheel, a second friction coefficient corresponding to the current steering torque is determined through a second mapping relationship, wherein the second mapping relationship is used to indicate the correspondence between the steering torque and the second friction coefficient;

[0223] The product of the first friction coefficient, the second friction coefficient, and the initial friction torque is determined as the target friction torque.

[0224] In one possible implementation, the second processing module 12 is further configured to:

[0225] Based on the pre-selected power steering level, the target friction torque is optimized to obtain the optimized target friction torque;

[0226] Accordingly, the control module 13 is specifically used for:

[0227] Friction compensation is performed on the output torque of the road sensor motor based on the optimized target friction torque.

[0228] In one possible implementation, the first processing module 11 is specifically used for:

[0229] The torque applied to the steering wheel is adjusted according to a pre-set torque curve, and the steering wheel speed is detected.

[0230] When the steering wheel reaches a uniform rotation speed and the rotation speed is stable, the dynamic friction torque is obtained based on the torque applied to the steering wheel.

[0231] In one possible implementation, the first processing module 11 is specifically used for:

[0232] When the number of effective torques applied to the steering wheel reaches a preset number, the average value of all effective torques is determined as the candidate dynamic friction torque. The effective torques include the torques applied when the steering wheel is rotating at a constant speed and the rotation speed is stable.

[0233] If the candidate dynamic friction torque is greater than a first preset threshold and less than a second preset threshold, then the candidate dynamic friction torque is determined as the dynamic friction torque.

[0234] If the candidate dynamic friction torque is equal to the first preset threshold or equal to the second preset threshold, then the candidate dynamic friction torque is determined as the dynamic friction torque;

[0235] The first preset threshold is less than the second preset threshold.

[0236] In one possible implementation, the first processing module 11 is further configured to:

[0237] If the candidate dynamic friction torque is less than the first preset threshold or greater than the second preset threshold, then the dynamic friction torque result of the vehicle in the previous initial state is determined as the dynamic friction torque.

[0238] The friction compensation device for the steer-by-wire system provided in this application embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effect are similar, and will not be described again here.

[0239] Figure 11 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Please refer to... Figure 11 The electronic device 20 provided in this application embodiment includes at least one processor 21 and a memory 22. Optionally, the device 20 further includes a communication component 23. The processor 21, memory 22, and communication component 23 are connected via a bus 24.

[0240] Optionally, the electronic device provided in this application embodiment may be an electronic control unit (ECU) or controller for controlling the steering wheel, used to execute the above-described method.

[0241] In the specific implementation process, at least one processor 21 executes computer execution instructions stored in memory 22, causing at least one processor 21 to perform the above-described method.

[0242] The specific implementation process of processor 21 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0243] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0244] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0245] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0246] This application provides a vehicle, including a vehicle body and... Figure 11 The electronic device shown is used to implement the friction compensation method of the steer-by-wire system in the above embodiments.

[0247] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0248] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0249] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0250] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0251] The division of units is merely a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0252] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0253] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0254] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0255] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0256] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A friction compensation method for a steer-by-wire system, characterized in that, include: The dynamic friction torque of the steering wheel is obtained. The dynamic friction torque is the friction torque that causes the steering wheel to rotate at a constant speed when the vehicle is in a target state. The target state includes the power-on synchronization state or the power-off return-to-center state. A friction torque curve is generated based on at least one steering wheel rotation speed, at least one static friction torque, and the dynamic friction torque of the vehicle during a historical period. The friction torque curve is used to represent the correspondence between friction torque and steering wheel rotation speed. The initial friction torque is determined by querying the friction torque curve based on the current steering wheel speed of the vehicle. Based on the current vehicle speed, a first friction coefficient corresponding to the current vehicle speed is determined through a first mapping relationship, wherein the first mapping relationship is used to indicate the correspondence between vehicle speed and the first friction coefficient; Based on the current steering torque of the steering wheel, a second friction coefficient corresponding to the current steering torque is determined through a second mapping relationship, wherein the second mapping relationship is used to indicate the correspondence between the steering torque and the second friction coefficient; The product of the first friction coefficient, the second friction coefficient, and the initial friction torque is determined as the target friction torque; Friction compensation is performed on the output torque of the road sensor motor based on the target friction torque. The method further includes: Based on the pre-selected power steering level, the target friction torque is optimized to obtain the optimized target friction torque. Different power steering levels correspond to different friction torque adjustment coefficients. The power steering level is selected and determined by the user based on the current driving environment. The target friction torque is determined based on the vehicle's current speed, the current steering torque of the steering wheel, and the initial friction torque. Friction compensation is performed on the output torque of the road sensor motor based on the optimized target friction torque.

2. The method according to claim 1, characterized in that, The acquisition of the dynamic friction torque of the steering wheel includes: The torque applied to the steering wheel is adjusted according to a pre-set torque curve, and the steering wheel speed is detected. When the steering wheel reaches a uniform rotation speed and the rotation speed is stable, the dynamic friction torque is obtained based on the torque applied to the steering wheel.

3. The method according to claim 2, characterized in that, The step of obtaining the dynamic friction torque based on the torque applied to the steering wheel includes: When the number of effective torques applied to the steering wheel reaches a preset number, the average value of all effective torques is determined as the candidate dynamic friction torque. The effective torques include the torques applied when the steering wheel is rotating at a constant speed and the rotation speed is stable. If the candidate dynamic friction torque is greater than a first preset threshold and less than a second preset threshold, then the candidate dynamic friction torque is determined as the dynamic friction torque. If the candidate dynamic friction torque is equal to the first preset threshold or equal to the second preset threshold, then the candidate dynamic friction torque is determined as the dynamic friction torque; The first preset threshold is less than the second preset threshold.

4. The method according to claim 3, characterized in that, The method further includes: If the candidate dynamic friction torque is less than the first preset threshold or greater than the second preset threshold, then the dynamic friction torque result of the vehicle in the previous initial state is determined as the dynamic friction torque.

5. A friction compensation device for a steer-by-wire system, characterized in that, include: The first processing module is used to acquire the dynamic friction torque of the steering wheel. The dynamic friction torque is the friction torque that causes the steering wheel to rotate at a constant speed when the vehicle is in a target state. The target state includes the power-on synchronization state or the power-off return-to-center state. The second processing module is used to generate a friction torque curve based on at least one steering wheel rotation speed, at least one static friction torque, and the dynamic friction torque of the vehicle during a historical period. The friction torque curve is used to represent the correspondence between friction torque and steering wheel rotation speed. The control module is used to query the friction torque curve based on the current steering wheel rotation speed of the vehicle to determine the initial friction torque; and to determine the first friction coefficient corresponding to the current vehicle speed through a first mapping relationship based on the current vehicle speed, wherein the first mapping relationship is used to indicate the correspondence between vehicle speed and the first friction coefficient. Based on the current steering torque of the steering wheel, a second friction coefficient corresponding to the current steering torque is determined through a second mapping relationship, wherein the second mapping relationship is used to indicate the correspondence between the steering torque and the second friction coefficient; The product of the first friction coefficient, the second friction coefficient, and the initial friction torque is determined as the target friction torque; friction compensation is performed on the output torque of the road sensor motor based on the target friction torque. The second processing module is further configured to: Based on the pre-selected power steering level, the target friction torque is optimized to obtain the optimized target friction torque. Different power steering levels correspond to different friction torque adjustment coefficients. The power steering level is selected and determined by the user based on the current driving environment. The target friction torque is determined based on the vehicle's current speed, the current steering torque of the steering wheel, and the initial friction torque. The control module is also used for: Friction compensation is performed on the output torque of the road sensor motor based on the optimized target friction torque.

6. An electronic device, characterized in that, include: Processor, memory; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory, causing the processor to perform the friction compensation method for the steer-by-wire system as described in any one of claims 1 to 4.

7. A vehicle, characterized in that, include: The vehicle body, and the electronic device as described in claim 6.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the friction compensation method for the steer-by-wire system as described in any one of claims 1 to 4.

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