Steer-by-wire system road feeling simulation control method and device based on Kalman filtering

Abstract

According to the steering-by-wire system road feeling simulation control method and device based on Kalman filtering, the problems that a current sensor is prone to being interfered, a fault diagnosis mechanism is incomplete, and road feeling feedback continuity is insufficient are solved. According to the method, an actual current signal of an execution motor is collected in real time, a Kalman filter is used for dynamically estimating current, and a high-precision estimated current signal is generated. When it is detected that the actual current signal fluctuates too much and the error e between the actual current signal and the estimated current continuously exceeds a preset threshold value, it is judged that the current sensor fails, and the estimated current signal is switched to serve as control input of road feeling simulation; and when the measured value and the estimated value are recovered to be basically matched and are continuously stable, switching to the actual current signal again. Through Kalman filtering and a dynamic switching mechanism, high reliability and continuity of road feeling feedback are achieved, meanwhile, fault diagnosis and fault-tolerant control capabilities are achieved, the method adapts to complex vehicle driving working conditions, and the safety and driving experience of a steer-by-wire system are remarkably improved.

Description

Technical Field

[0001] The technical field of the present invention should belong to the technical fields of vehicle engineering and automatic control technology, and specifically relates to a road feel simulation control method and device for a steer-by-wire system based on Kalman filtering. Background Art

[0002] With the rapid development of automotive electronic technology, the steer-by-wire system (SBW), as an advanced steering control technology, has gradually become a research hotspot in the fields of intelligent driving and electric vehicles. The steer-by-wire system replaces the traditional mechanical connection with electronic signals, eliminating the direct mechanical linkage between the steering wheel and the steering wheel, thereby enabling more flexible steering control, higher energy efficiency, and a better driving experience. However, the steer-by-wire system also faces many technical challenges, one of which is how to provide real and reliable road feel feedback to the driver in the absence of a mechanical connection.

[0003] Road feel feedback is an important way for drivers to perceive the driving state of vehicles, directly affecting driving safety and handling experience. In the steer-by-wire system, road feel feedback is usually simulated by the current signal of the actuator motor. The current signal of the actuator motor can reflect the load change of the steering system, and then generate a feedback torque matching the road conditions. However, the measurement accuracy and reliability of the current signal directly determine the quality of road feel feedback. In practical applications, current sensors may be affected by factors such as electromagnetic interference, mechanical vibration, or hardware aging, resulting in fluctuations or distortions in the measurement signal. Once the current sensor fails, the accuracy of road feel feedback will be seriously affected, and even potential safety hazards may be caused.

[0004] To solve the problem of current sensor failure, redundant design or fault diagnosis mechanisms are usually adopted in the prior art. For example, some solutions achieve redundant measurement by adding multiple current sensors, but this method will increase system complexity and cost. Other solutions detect sensor faults through simple threshold judgment or filtering algorithms, but these methods often have difficulty coping with complex dynamic working conditions and are prone to misjudgment. In addition, there is a lack of a mechanism in the prior art that can seamlessly switch to a backup signal source when the sensor fails, resulting in insufficient continuity and stability of road feel feedback.

[0005] As a classic state estimation algorithm, the Kalman filter is widely used in the fields of automatic control, signal processing, and fault diagnosis. Through the dynamic prediction and correction process, it can effectively suppress noise interference and improve the accuracy of state estimation. In a steer-by-wire system, the Kalman filter can be used to estimate the current signal of the actuator motor, thereby providing a reliable backup signal source for road feel feedback. However, in the existing technology, the application potential of the Kalman filter in road feel simulation of the steer-by-wire system has not been fully explored, especially in seamless switching and dynamic recovery when sensors fail.

[0006] In summary, the following deficiencies still exist in the existing technology in the road feel simulation control of the steer-by-wire system: 1. The measurement signal of the current sensor is vulnerable to interference, and there is a lack of an efficient fault detection and fault tolerance mechanism; 2. The existing fault diagnosis methods are difficult to adapt to complex dynamic working conditions and are prone to misjudgment; 3. There is a lack of a control strategy that can seamlessly switch to a backup signal source and dynamically recover when the sensor fails. Summary of the Invention

[0007] To solve the above problems, the present invention provides a road feel simulation control method and device for a steer-by-wire system based on the Kalman filter to improve the reliability, continuity, and dynamic adaptability of road feel feedback, thereby providing a safer and more comfortable driving experience for drivers.

[0008] To achieve the above object, the present invention adopts the following technical solutions: A road feel simulation control method for a steer-by-wire system based on the Kalman filter includes the following steps: (1) Real-time collect the actual current signal I meas of the actuator motor in the steer-by-wire system, and dynamically estimate the current of the actuator motor through a Kalman filter to generate a corresponding estimated current signal I est; (2) Calculate the real-time error value e between the actual current signal and the estimated current signal; (3) When it is detected that the fluctuation amplitude of the actual current signal exceeds a preset threshold e th, and the error value e continuously exceeds the preset threshold for a first set duration T fault, determine that the current sensor fails, trigger a fault flag, and switch to using the estimated current signal I est of the Kalman filter as the control input for road feel simulation; (4) In the state where the current sensor fails, continuously monitor the error value e between the actual current signal and the estimated current signal; when the error value e is continuously lower than 80% of the threshold for a second set duration TDuring recovery, it is determined that the current sensor has returned to normal, the fault flag is cleared, and the actual current signal is re-switched as the control input for road feel simulation. (5)Generate a road feel feedback torque based on the switched current signal and output it to the steering wheel through the steering actuator.

[0009] A further improvement of the present invention is that the Kalman filter includes a state equation and an observation equation constructed based on the dynamic model of the actuator motor. The dynamic model includes the electrical equation and the mechanical equation of the motor. The state variables at least include the motor current I, the motor speed ω, and the load torque T, and the observed variable is the actual current signal. The Kalman filter generates an estimated current signal through a real-time iterative prediction and correction process.

[0010] A further improvement of the present invention is that the conditions for determining the failure of the current sensor in step (3) further include: Perform a frequency domain analysis on the actual current signal. If it is detected that the amplitude of the high-frequency noise exceeds a preset third threshold, trigger the adaptive adjustment mechanism of the Kalman filter to dynamically correct the filtering parameters to suppress noise interference; The threshold is a dynamic threshold, and its value is adaptively adjusted according to the current vehicle speed, the steering wheel input torque, and the vehicle driving state.

[0011] A further improvement of the present invention is that in steps (3) and (4), the first set duration and the second set duration are dynamically set according to the vehicle driving conditions: the set duration is shortened under high-speed driving conditions to improve the switching sensitivity, and the set duration is extended under low-speed or frequent steering conditions to reduce the probability of false triggering.

[0012] A further improvement of the present invention is that when switching to the estimated current signal of the Kalman filter in step (3), it further includes: Record the abnormal fluctuation characteristics of the current actual current signal and input this characteristic into the fault diagnosis module to generate a fault code and store it in the vehicle-mounted memory; Send an abnormal current sensor prompt message to the driver through the vehicle-mounted human-machine interface.

[0013] A further improvement of the present invention is that before re-switching to the actual current signal in step (4), it further includes: Perform a moving window mean filtering process on the actual current signal and calculate its moving average error from the estimated current signal; When the moving average error is lower than 80% of the second threshold for N consecutive sampling periods, perform the switching operation, where N is dynamically set according to the vehicle control period.

[0014] A further improvement of the present invention lies in that the input of the Kalman filter further includes a steering wheel angle signal, a vehicle yaw rate signal, and an estimated value of the tire lateral force, which are used to construct a multi-dimensional fusion observation model to improve the current estimation accuracy.

[0015] A road feeling simulation control device for a steer-by-wire system, which is based on the above-mentioned road feeling simulation control method for a steer-by-wire system based on Kalman filtering, includes: A current acquisition module for real-time acquisition of the actual current signal of the actuator motor; A Kalman filtering module that generates an estimated current signal based on a dynamic model, where the dynamic model includes the electrical equation and mechanical equation of the motor, and the state variables at least include the motor current I, the motor speed ω, and the load torque T, and the observed variable is the actual current signal; A fault diagnosis module for performing error calculation, threshold comparison, and switching logic; A redundant control module that enables the estimated current signal when the current sensor fails and synchronously updates the calculation parameters of the road feeling feedback torque; An output interface module that sends the road feeling feedback torque to the steering actuator.

[0016] A further improvement of the present invention lies in that the redundant control module further includes: A historical data storage unit for caching the actual current signal and the estimated current signal within the most recent T seconds; A data compensation unit that, when switching to the estimated current signal, performs weighted correction on the current estimated value based on historical data, where the weight coefficient is negatively correlated with the duration of the sensor failure.

[0017] A vehicle electronic control unit includes a processor and a memory, and the memory stores a computer program, which, when executed by the processor, implements the steps of the above-mentioned road feeling simulation control method for a steer-by-wire system based on Kalman filtering.

[0018] Compared with the prior art, the present invention has at least the following beneficial technical effects: The present invention realizes at least the following advantages by introducing the Kalman filtering algorithm and the dynamic switching mechanism: By using Kalman filtering to estimate the current signal of the actuator motor in real time, it can provide a reliable backup signal source when the current sensor fails, ensuring the continuity and stability of the road feeling feedback.

[0019] The fault detection mechanism based on the error value e and the dynamic threshold can accurately identify the abnormal state of the current sensor and effectively reduce the misjudgment probability.

[0020] When the sensor fails and then returns to normal, the system can seamlessly switch the signal source, and ensure the smoothness and reliability of the switching process through moving window mean filtering and dynamic threshold judgment.

[0021] By dynamically adjusting the threshold and filtering parameters, the present invention can adapt to different vehicle driving conditions, including scenarios such as high-speed driving, low-speed steering, and frequent lane changes.

[0022] Compared with traditional redundancy designs, the present invention realizes fault tolerance through software algorithms, without the need to increase additional hardware costs, and has high economic efficiency and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 It is a schematic structural diagram of the steer-by-wire system of the present invention.

[0025] Figure 2 It is a schematic diagram of the steer-by-wire road feel simulation control method in the present invention.

[0026] Figure 3 It is a flowchart of the fault tolerance control method provided in the present invention.

[0027] Figure 4 It is an angle input diagram in Embodiment 2 of the present invention.

[0028] Figure 5 It is a schematic diagram of the measured current value Imeas of the sensor and the estimated current value Iest of the Kalman filter in Embodiment 2 of the present invention.

[0029] Figure 6 It is an image of the current correction value changing with time in Embodiment 2 of the present invention.

[0030] Figure 7 It is an image of the road feel feedback torque calculated according to the current correction value in Embodiment 2 of the present invention.

[0031] Figure 8 It is a comparison diagram of the road feel feedback values between using the road feel simulation control method of the present invention and not using the road feel simulation control method of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] In the following text, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present invention. Therefore, the accompanying drawings and the description are considered to be exemplary in nature rather than restrictive.

[0033] In the description of the present invention, it should be understood that when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0034] It should also be understood that the terms used in the specification of the present invention are merely for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0035] It should be further understood that the term "and / or" used in the specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0036] Various schematic structural diagrams according to the disclosed embodiments of the present invention are shown in the accompanying drawings. These figures are not drawn to scale, where for the purpose of clear expression, some details are enlarged, and some details may be omitted. The shapes of various regions and layers shown in the figures and their relative sizes and positional relationships are merely exemplary, and may actually deviate due to manufacturing tolerances or technical limitations, and those skilled in the art can design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0037] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0038] Embodiment 1 The road feel simulation control method for a steer-by-wire system based on Kalman filtering provided by the present invention specifically includes the following: Real-time collect the actual current signal of the actuator motor in the steer-by-wire system I meas, and dynamically estimate the current of the actuator motor through a Kalman filter to generate a corresponding estimated current signal Iest. The state equation and observation equation of the Kalman filter are constructed based on the dynamic model of the actuating motor. The state variables include the motor current I, the motor speed ω, and the load torque T, and the observed variable is the actual current signal. The Kalman filter generates a high-precision estimated current signal through a real-time iterative prediction and correction process.

[0039] Calculate the real-time error value e between the actual current signal and the estimated current signal. When it is detected that the fluctuation amplitude of the error value exceeds a preset threshold and continuously exceeds the preset threshold for a first set duration, it is determined that the current sensor has failed. The threshold is dynamically adjusted according to the vehicle driving state to adapt to different working conditions.

[0040] When it is determined that the current sensor has failed, switch to using the estimated current signal of the Kalman filter as the control input for road feel simulation. During the switching process, the system records the abnormal fluctuation characteristics of the current actual current signal and inputs this characteristic into the fault diagnosis module to generate a fault code and store it in the vehicle-mounted memory. At the same time, an abnormal prompt message for the current sensor is sent to the driver through the vehicle-mounted human-machine interface.

[0041] In the state where the current sensor has failed, continuously monitor the error value e between the actual current signal and the estimated current signal. When the error value e is continuously lower than the threshold for a second set duration, it is determined that the current sensor has returned to normal. Before switching back to the actual current signal, perform a sliding window mean filtering process on the actual current signal and calculate its sliding average error with the estimated current signal. When the sliding average error is continuously lower than 80% of the second threshold for N sampling periods, perform the switching operation and resume using the actual current signal as the control input for road feel simulation.

[0042] The road feel feedback torque is generated. The road feel feedback torque is generated based on the current signal and output to the steering wheel through the steering actuator. The calculation of the road feel feedback torque comprehensively considers factors such as vehicle speed, steering wheel angle, vehicle yaw rate, and tire lateral force to ensure the authenticity and dynamic adaptability of the feedback torque.

[0043] As Figure 1 shown, the present invention is applied to a steer-by-wire system. Although the steer-by-wire system has many advantages, it also faces many technical challenges. How to provide real and reliable road feel feedback to the driver is one of them. As Figure 2As shown in the figure, the present invention uses the current of the actuator motor as the main source of the road feel feedback torque to provide appropriate steering resistance for the driver. However, the actuator motor current sensor may be affected by unpredictable factors such as electromagnetic interference, mechanical vibration, or hardware aging, resulting in sensor failure. Once the current sensor fails, the accuracy of the road feel feedback will be seriously affected, and even potential safety hazards may be caused. Therefore, this paper provides a road feel simulation control method for a steer-by-wire system based on Kalman filtering. As Figure 3 shown.

[0044] When the steer-by-wire system is working properly, first, the required data is collected in real time, including obtaining the actuator motor current I meas through the current sensor, and obtaining the motor speed ω through the encoder or speed sensor, etc. Then, the steering actuator motor current is estimated by the designed Kalman filter to obtain the estimated value I est. After that, error detection and fault judgment are performed on the actuator motor current, and the real-time error value e between the actual current signal and the estimated current signal is calculated; When it is detected that the fluctuation amplitude of the actual current signal exceeds the preset threshold e th, and the error value e continuously exceeds the preset threshold for the first set duration T fault, it is determined that the current sensor fails, a fault flag is triggered, and the estimated current signal of the Kalman filter is switched to be used I est as the control input for road feel simulation; in the state of current sensor failure, the error value e between the actual current signal and the estimated current signal is continuously monitored; when the error value e is continuously lower than 80% of the threshold for the second set duration T recover, it is determined that the current sensor returns to normal, the fault flag is cleared, and the actual current signal is switched back as the control input for road feel simulation; finally, the road feel feedback torque is generated according to the switched current signal and output to the steering wheel through the steering actuator to provide appropriate road feel feedback for the driver.

[0045] Embodiment 2 The sine working condition is selected to illustrate the implementation case of the present invention. Test working condition setting: At a vehicle speed of 20 km / h, a steering wheel angle input with a period of 5 s and an amplitude of 300° is set. The angle input diagram is as Figure 4 shown.

[0046] Set the current sensor fault: 0 - 5 s, no fault; 5 - 10 s, 0.5 times the current sensor gain fails; 10 - 15 s, no fault, 15 - 20 s, the current sensor completely fails Then the measured current value Imeas of the sensor and the estimated current value Iest of the Kalman filter are as Figure 5as shown

[0047] According to the road feeling simulation control method of the present invention, an image of the current correction value changing with time can be obtained as Figure 6 as shown

[0048] An image of the road feeling feedback torque calculated according to the current correction value is as Figure 7 as shown

[0049] The comparison of the road feeling feedback values between using the road feeling simulation control method of the present invention and not using it is as follows: as Figure 8 shown, it can be seen that when this method is not used, when the current sensor fails, a suitable road feeling torque cannot be fed back, posing a safety hazard to the driving process; using the present invention can still output a suitable road feeling feedback steering wheel torque when the current sensor fails, improving the safety and fault tolerance of the steer-by-wire system.

[0050] Embodiment 3 A steer-by-wire system road feeling simulation control device provided by the present invention, which is based on the above-mentioned steer-by-wire system road feeling simulation control method based on Kalman filter, includes: A current acquisition module, configured to acquire the actual current signal of the actuator motor in real time; A Kalman filter module, which generates an estimated current signal based on a dynamic model, and the dynamic model includes the electrical equation and mechanical equation of the motor, where the state variables at least include the motor current I, the motor speed ω, and the load torque T, and the observed variable is the actual current signal; A fault diagnosis module, configured to perform error calculation, threshold comparison, and switching logic; A redundant control module, which enables the estimated current signal when the current sensor fails, and synchronously updates the calculation parameters of the road feeling feedback torque; An output interface module, which sends the road feeling feedback torque to the steering actuator.

[0051] In this embodiment, the redundant control module further includes: A historical data storage unit, configured to cache the actual current signal and the estimated current signal within the most recent T seconds; A data compensation unit, which performs weighted correction on the current estimated value based on historical data when switching to the estimated current signal, where the weight coefficient is negatively correlated with the duration of the sensor failure.

[0052] Embodiment 4 A vehicle electronic control unit provided by the present invention includes a processor and a memory, and the memory stores a computer program, and when the program is executed by the processor, the steps of the above-mentioned steer-by-wire system road feeling simulation control method based on Kalman filter are implemented.

[0053] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, an apparatus, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0054] The present application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses, and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the specified functions in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0055] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device, and the instruction device implements the specified functions in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0056] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the specified functions in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0057] The foregoing has shown and described the basic principles, main features and advantages of the present invention. For a person skilled in the art, it is obvious that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and without departing from the spirit or basic features of the present invention, the present invention can be implemented in other specific forms. Therefore, in any aspect, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced by the present invention. Any reference signs in the claims should not be construed as limiting the claims concerned.

[0058] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative manner of the specification is only for clarity. A person skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by a person skilled in the art. The above content is only to illustrate the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any modification made on the basis of the technical solution according to the technical idea proposed by the present invention falls within the protection scope of the claims of the present invention.

Claims

1. A road feel simulation control method for a steer-by-wire system based on Kalman filtering, characterized in that: The following steps are involved: (1) Real-time acquisition of the actual current signal of the actuator motor in the steer-by-wire system I meas, and dynamically estimate the current of the actuator motor through the Kalman filter to generate the corresponding estimated current signal I est; (2) Calculate the real-time error value e between the actual current signal and the estimated current signal; (3) When the fluctuation amplitude of the actual current signal exceeds the preset threshold e th, and the error value e continues to exceed the preset threshold for a first set time period T fault, determine that the current sensor fails, trigger the fault flag, and switch to the estimated current signal using the Kalman filter I est as the control input for road feel simulation; (4) When the current sensor fails, the error value e between the actual current signal and the estimated current signal is continuously monitored; when the error value e is continuously lower than 80% of the threshold value for a second set time period T When recovering, it is determined that the current sensor has returned to normal, the fault flag is cleared, and the actual current signal is switched back to the control input of the road sense simulation; (5) A road feel feedback torque is generated based on the switched current signal and output to the steering wheel through the steering actuator.

2. The road feel simulation control method of the steer-by-wire system based on Kalman filtering according to claim 1, characterized in that: The Kalman filter includes a state equation and an observation equation based on a dynamic model of the execution motor, wherein the dynamic model includes an electrical equation and a mechanical equation of the motor, wherein the state variables include at least the motor current I, the motor speed ω and the load torque T, and the observation variable is the actual current signal; The Kalman filter generates an estimated current signal through a real-time iterative prediction and correction process.

3. The road feel simulation control method of a steer-by-wire system based on Kalman filtering according to claim 1, characterized in that: The conditions for determining that the current sensor fails in step (3) also include: Perform frequency domain analysis on the actual current signal. If the high-frequency noise amplitude is detected to exceed the preset third threshold, the adaptive adjustment mechanism of the Kalman filter is triggered to dynamically correct the filter parameters to suppress noise interference. The threshold is a dynamic threshold, and its value is adaptively adjusted according to the current vehicle speed, steering wheel input torque and vehicle driving status.

4. The road feel simulation control method of a steer-by-wire system based on Kalman filtering according to claim 1, characterized in that: In steps (3) and (4), the first set time and the second set time are dynamically set according to the vehicle driving conditions: the set time is shortened under high-speed driving conditions to improve the switching sensitivity, and the set time is extended under low-speed or frequent turning conditions to reduce the probability of false triggering.

5. The road feel simulation control method of a steer-by-wire system based on Kalman filtering according to claim 1, characterized in that: When the step (3) switches to the Kalman filter to estimate the current signal, it also includes: Record the abnormal fluctuation characteristics of the current actual current signal, and input the characteristics into the fault diagnosis module to generate a fault code and store it in the vehicle memory; The current sensor abnormality prompt information is sent to the driver through the on-board human-machine interface.

6. The road feel simulation control method of a steer-by-wire system based on Kalman filtering according to claim 1, characterized in that: Before switching back to the actual current signal in step (4), the method further comprises: Perform sliding window mean filtering on the actual current signal and calculate the sliding average error between it and the estimated current signal; When the sliding average error is lower than 80% of the second threshold for N consecutive sampling periods, the switching operation is performed, where N is dynamically set according to the vehicle control cycle.

7. The road feel simulation control method of a steer-by-wire system based on Kalman filtering according to claim 1, characterized in that: The input of the Kalman filter also includes a steering wheel angle signal, a vehicle yaw angular velocity signal and a tire lateral force estimation value, which are used to construct a multi-dimensional fusion observation model to improve the current estimation accuracy.

8. A road feel simulation control device for a steer-by-wire system, characterized in that: The device is based on the road feel simulation control method of the steer-by-wire system based on Kalman filtering as claimed in claim 1, comprising: Current acquisition module, used to obtain the actual current signal of the actuator motor in real time; A Kalman filter module generates an estimated current signal based on a dynamic model, wherein the dynamic model includes electrical equations and mechanical equations of the motor, wherein state variables include at least motor current I, motor speed ω, and load torque T, and an observed variable is an actual current signal; a fault diagnosis module for performing error calculation, threshold comparison, and switching logic; A redundant control module enables the estimated current signal when the current sensor fails and simultaneously updates the calculation parameters of the road sense feedback torque; The output interface module sends the road sense feedback torque to the steering actuator.

9. The road feel simulation control device for a steer-by-wire system according to claim 8, characterized in that: The redundant control module further includes: A historical data storage unit, used to cache the actual current signal and the estimated current signal within the last T seconds; The data compensation unit, when switching to the estimated current signal, performs weighted correction on the current estimated value based on historical data, wherein the weight coefficient is negatively correlated with the duration of the sensor failure.

10. A vehicle electronic control unit, characterized in that: The method comprises a processor and a memory, wherein the memory stores a computer program, and when the program is executed by the processor, the steps of the road feel simulation control method of a steer-by-wire system based on Kalman filtering as described in any one of claims 1 to 7 are implemented.

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