Vehicle deviation compensation method based on steer-by-wire

Abstract

The invention discloses a vehicle deviation compensation method based on steer-by-wire, relates to the technical field of automobile control, and solves the technical problems that dynamic response cannot be performed in real time, compensation for dynamic interference such as crosswind and load change lags behind, the compensation strategy is single, and a multi-system cooperative comprehensive compensation scheme is lacked. According to the method, crosswind, acceleration and linear deviation are distinguished through comprehensive judgment of multiple parameters such as vehicle speed, yaw velocity, steering wheel torque and lane line deviation, 'reason-strategy 'accurate matching is achieved, ideal state parameters are calculated through a linear two-degree-of-freedom model and an aerodynamic formula, compensation torque is generated in real time in combination with a PID control algorithm, and the compensation effect is achieved. The controller can memorize the compensation amount corresponding to the deviation of the positioning parameters, PID parameters are optimized on line through a recursive least square method, time-varying factors such as tire wear and suspension aging are adapted, and the manual calibration frequency is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle control, and specifically to a method for compensating vehicle deviation based on steer-by-wire steering. Background Art

[0002] During the actual driving process of a vehicle, the driving situation of vehicle deviation often occurs due to external conditions of the vehicle body. Vehicle deviation is one of the common faults in vehicle use, which often requires the driver to adjust manually, affecting the user driving experience and easily causing potential safety hazards.

[0003] According to the patent application with the publication number CN117184225A, an optimized method and device for compensating vehicle deviation are disclosed. This method is applied to the technical field of vehicle control, and the method includes: detecting whether the vehicle is in a deviation compensation state; when it is detected that the vehicle is in a deviation compensation state, determining whether at least one state signal of the vehicle meets a preset condition; if any signal in at least one state signal meets the preset condition, determining a corresponding deviation compensation optimization value according to the actual process of the deviation compensation state, and using the deviation compensation optimization value to optimize the actual deviation compensation torque of the actual process.

[0004] However, when some existing vehicle deviation compensation methods are used, they cannot perform dynamic response in real time, the compensation for dynamic interferences such as crosswind and load changes lags behind, and at the same time, the compensation strategy is single, lacking a comprehensive compensation scheme for multi-system collaboration. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a method for compensating vehicle deviation based on steer-by-wire steering, which solves the problems of inability to perform dynamic response in real time, lagging compensation for dynamic interferences such as crosswind and load changes, single compensation strategy, and lack of a comprehensive compensation scheme for multi-system collaboration.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: A method for compensating vehicle deviation based on steer-by-wire steering, which specifically includes the following steps:

[0007] Compare the vehicle driving state signal with a preset deviation adjustment to generate crosswind deviation, acceleration deviation, and straight-line deviation;

[0008] Perform compensation processing on the crosswind deviation, calculate the aerodynamic side force according to the formula, and calculate the expected yaw rate in combination with the vehicle dynamics model, and calculate the total compensation torque through the PID control algorithm to generate crosswind deviation compensation information;

[0009] Perform compensation processing on the acceleration deviation, calculate the ideal yaw rate and the ideal lateral angular velocity according to the vehicle linear two-degree-of-freedom model, and at the same time calculate the differences between the two and the corresponding thresholds, and determine whether it is acceleration deviation according to the differences;

[0010] For the analysis of acceleration deviation, calculations are performed through the PID control algorithm. The proportional, integral, and derivative links are calculated separately and summed to obtain the compensation control quantity, generating acceleration deviation compensation information;

[0011] For the compensation of straight-line deviation, calculate the differences between the lateral offset and the heading angle deviation and their corresponding thresholds. Combine the two to determine the straight-line deviation, and further determine it in combination with the steering wheel torque and the turn signal activation status, generating deviation detection compensation information;

[0012] Analyze the deviation detection compensation information, compare the positioning parameters with the standard values in the vehicle manual to determine the abnormal positioning parameters, and determine the corresponding compensation processing method according to the abnormal positioning parameters, generating parameter compensation adjustment information.

[0013] As a further aspect of the present invention, the specific methods for generating crosswind deviation, acceleration deviation, and straight-line deviation are as follows:

[0014] Collect the vehicle speed, yaw rate, steering wheel angle, and steering gear position, and compare them with the preset deviation conditions. If all conditions are met, it is determined that the vehicle is not deviated, generating normal monitoring information. If any signal does not meet the conditions, it is determined that the vehicle is deviated, generating deviation analysis information, and the compensation types include crosswind, acceleration, and straight-line deviation.

[0015] As a further aspect of the present invention, the specific method for compensating crosswind deviation is as follows:

[0016] According to the formula calculate the corresponding aerodynamic side force F of the vehicle y , where ρ is the air density, C y is the side force coefficient, A is the frontal area of the vehicle, and V wind is the crosswind speed of the vehicle;

[0017] According to the formula M z = F y ·h cg calculate the yaw moment M z of the vehicle, where h cg is the height of the vehicle's center of mass. At the same time, obtain the steering wheel angle δ of the driver and the real-time vehicle speed v, and use the vehicle dynamics model to calculate the desired yaw rate ω des , where L is the wheelbase of the vehicle and K is the vehicle stability factor. Calculate the yaw rate deviation Δω = ω dse - ω act , where ω act is the actual yaw rate.

[0018] As a further aspect of the present invention, the specific method for generating crosswind deviation compensation information is as follows:

[0019] Introduce a proportional link, M comp-p = K p ·Δω where K p is the proportional coefficient;

[0020] Introduce an integral link M comp-i = K i ∫Δωdt, where K i is the integral coefficient;

[0021] Introduce a differential link where K d is the differential coefficient;

[0022] Sum the three to calculate the total compensation torque M comp = M comp-p + M comp-i + M comp-d , and generate crosswind deviation compensation information based on the total compensation torque as the standard.

[0023] As a further solution of the present invention, the specific method for compensating for acceleration deviation is as follows:

[0024] Based on the vehicle linear two-degree-of-freedom model Calculate the ideal yaw angular velocity ω of the vehicle r-ideal , where δ is the steering wheel angle and v is the real-time vehicle speed. At the same time, according to the formula a y-ideal = v·ω e-ideal Calculate the ideal lateral acceleration a y-ideal ;

[0025] Set the yaw angular velocity deviation threshold Δω r-thershold and the lateral acceleration deviation threshold Δa y-threshold , calculate the deviation between the actual and ideal values, Δω r = |ω r-actual - ω r-ideal |, where ω r-actual is the actual yaw angular velocity, Δa y = |a y-actual - a y-ideal |, where a y-ideal is the actual lateral acceleration;

[0026] If Δω r > Δω r-threshold and Δa y > Δa y-threshold , or a single deviation exceeds the threshold and lasts for a certain period of time, it is determined as instantaneous deviation, and acceleration deviation compensation information is generated.

[0027] As a further solution of the present invention, the specific method for generating the acceleration deviation compensation information is as follows:

[0028] For the proportional link calculation, u p = K p ·Δω r , where K p is the proportional coefficient;

[0029] For the integral link calculation, u i = K i ·Δω r , where K i is the integral coefficient;

[0030] For the differential link calculation, u d = K d ·Δω r , where K d is the differential coefficient;

[0031] According to the formula u = u p + u i + u d calculate the total compensation control amount, and generate the acceleration deviation compensation information at the same time.

[0032] As a further solution of the present invention, the specific method for compensating the straight-line deviation is as follows:

[0033] After the in-vehicle camera collects the image, extract the candidate lane line area through threshold segmentation or edge detection, convert it into the physical coordinates of the vehicle coordinate system by using the homography matrix, calculate the lateral offset d and the heading angle deviation θ, and at the same time monitor whether the steering wheel angle is near the "zero position";

[0034] Set the lateral offset threshold d th and the heading angle deviation threshold θ th . If |d| > d th and |θ| > θ th , and the duration t > t th , it is determined that the straight-line deviation is caused by abnormal positioning, and the straight-line deviation compensation information is generated;

[0035] Detect the steering wheel torque T sw through the torque sensor. If T sw > T th or the turn signal is detected to be turned on, it is determined that the driver is operating actively and no compensation is triggered. Otherwise, the deviation detection compensation information is generated.

[0036] As a further solution of the present invention, the specific method for analyzing the deviation detection compensation information is as follows:

[0037] Obtain the distances D between the vehicle and the left and right lane lines through the in-vehicle cameraL and D R If D L >D R it is determined that the vehicle is running off to the right, and a right - hand running - off signal is generated. If D L <D R it is determined that the vehicle is running off to the left, and a left - hand running - off signal is generated;

[0038] Taking the mid - point of the lane in the lateral direction as the origin, calculate the distance difference D c = D R - D L and perform reverse adjustment in combination with the generated running - off signal. At the same time, calculate the compensation angle δ according to the proportional relationship comp = - K p ·D c where K p is the proportional gain, and generate parameter running - off compensation information based on it.

[0039] The present invention provides a method for compensating vehicle running - off based on steer - by - wire. Compared with the prior art, it has the following beneficial effects:

[0040] The present invention makes a comprehensive judgment through multiple parameters such as vehicle speed, yaw rate, steering wheel torque, and lane line deviation, differentiates cross - wind, acceleration, and straight - line running - off, realizes accurate matching of "cause - strategy", calculates ideal state parameters through a linear two - degree - of - freedom model and aerodynamic formula, generates a compensation torque in real - time in combination with a PID control algorithm. The controller can memorize the compensation amount corresponding to the positioning parameter deviation, and online optimize the PID parameters through the recursive least - squares method to adapt to time - varying factors such as tire wear and suspension aging, and reduce the frequency of manual calibration.

[0041] The present invention also identifies the lane line deviation through a camera, reversely deduces the positioning parameter deviation, automatically triggers the adjustment of the steering tie rod or the modification of the suspension component parameters, realizes the full - process automation of "detection - analysis - adjustment", differentiates active steering and passive running - off through the steering wheel torque sensor and the turn signal, avoids mis - compensation, and improves the system safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a flowchart of the method steps of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0044] Please refer toFigure 1 The present application provides a vehicle deviation compensation method based on steer-by-wire, and the method specifically includes the following steps:

[0045] Step S1: Collect signals characterizing the vehicle driving state, where the vehicle driving state signals include vehicle speed signal, yaw rate signal, steering wheel angle signal, and steering gear position signal. At the same time, compare the obtained vehicle driving state signals with a preset deviation condition, and the preset deviation condition specifically refers to steering wheel angle, steering wheel rotation speed, steering wheel torque, and lateral acceleration;

[0046] If all the vehicle driving state signals meet the preset deviation condition, it means that the vehicle is not deviating in the current driving state, and normal monitoring information is generated. On the contrary, if any group of the vehicle driving state signals does not meet the preset deviation condition, it means that the vehicle is deviating in the current driving state, and deviation compensation analysis information is generated, and the specific deviation compensation includes crosswind deviation, acceleration deviation, and straight-line deviation.

[0047] Step S2: Perform crosswind deviation compensation processing on the generated deviation compensation analysis information, and the specific compensation processing method is as follows:

[0048] Obtain the frontal area A of the vehicle, and directly obtain the designed value of the frontal area of the vehicle from the vehicle design drawings or technical documents. At the same time, obtain the crosswind speed V of the vehicle wind , and install an anemometer at a suitable position outside the vehicle (such as the roof) to measure the crosswind speed in real time. Then substitute the obtained parameters into the formula Calculate the corresponding aerodynamic lateral force F of the vehicle y , where ρ is the air density, C y is the lateral force coefficient, and is obtained by numerically simulating the air flow around the vehicle using computational fluid dynamics (CFD) software;

[0049] According to the calculated aerodynamic lateral force F y , according to the formula M z =F y ·h cg Calculate the yaw moment M of the vehicle z , where h cg is the height of the vehicle's center of mass. At the same time, obtain the steering wheel angle δ of the driver and the real-time vehicle speed v, and calculate the desired yaw rate ω using the vehicle dynamics model des , and the specific calculation formula is where L is the wheelbase of the vehicle, and K is the vehicle stability factor, and the specific calculation formula is where m is the mass of the vehicle, a is the distance from the center of mass to the front axle, b is the distance from the center of mass to the rear axle, C f is the front wheel cornering stiffness, C ris the cornering stiffness of the rear wheels. At the same time, calculate the yaw rate deviation Δω = ω dse - ω act , where ω act is the actual yaw rate, which is measured by a yaw rate sensor;

[0050] Then, calculate the compensation torque according to the obtained yaw rate deviation Δω. The specific calculation formula is M comp-p = K p ·Δω, where K p is the proportionality coefficient;

[0051] To eliminate the steady-state deviation, an integral link M comp-i = K i ∫Δωdt is introduced, where K i is the integral coefficient;

[0052] To suppress the rapid change of the deviation, a differential link is introduced, where K d is the differential coefficient, and the sum of the three is calculated to obtain the total compensation torque M comp = M comp-p + M comp-i + M comp-d . At the same time, generate the crosswind deviation compensation information based on the total compensation torque, and transmit the crosswind deviation compensation information to the steering mechanism assembly. The steering mechanism assembly adjusts the crosswind deviation. During the adjustment, the compensation process can be provided or not provided to the corresponding driver.

[0053] Step S3: Perform the acceleration deviation compensation process on the generated deviation compensation analysis information. The specific compensation process is as follows:

[0054] Obtain the driver's steering wheel angle δ and the real-time vehicle speed v, and calculate the ideal yaw rate ω of the vehicle based on the vehicle linear two-degree-of-freedom model r-ideal . At the same time, calculate the ideal lateral acceleration a y-ideal = v·ω e-ideal according to the formula a y-ideal ;

[0055] For the yaw rate, set the yaw rate deviation threshold Δω r-thershold . For the lateral acceleration, set the lateral acceleration deviation threshold Δa y-threshold . These specific thresholds can be determined according to the vehicle type, performance, and actual test experience. Calculate the yaw rate deviation between the actual yaw rate and the ideal yaw rate, Δω r = |ω r-actual - ω r-ideal |, where ω r-actualis the actual yaw rate. At the same time, calculate the lateral acceleration deviation between the actual lateral acceleration and the ideal lateral acceleration, Δa y =|a y-actual -a y-ideal |, where a y-ideal is the actual lateral acceleration;

[0056] Compare the obtained yaw rate deviation and lateral acceleration deviation comprehensively with the yaw rate deviation threshold Δω r-thershold and the lateral acceleration deviation threshold Δa y-threshold . If Δω r >Δω r-threshold and Δa y >Δa y-threshold , or when one of the deviation values exceeds the corresponding threshold and lasts for a certain period of time, it is determined that the vehicle has an instantaneous deviation, and acceleration deviation compensation information is generated;

[0057] Then calculate the compensation control amount u according to the calculated yaw angular acceleration Δω r and lateral acceleration Δa y . Calculate through the PID control algorithm, calculate and sum the proportional link, integral link and differential link respectively to obtain the compensation control amount;

[0058] Calculate for the proportional link: u p =K p ·Δω r or u p =K p ·Δa y , where K p is the proportional coefficient;

[0059] Calculate for the integral link: u i =K i ·Δω r or u i =K i ·Δa y , where K i is the integral coefficient;

[0060] Calculate for the differential link: u d =K d ·Δω r or u d =K d ·Δa y , where K d is the differential coefficient;

[0061] Sum up the calculated u p , u i and u d . u = u p +ui +u d The total compensation control amount is calculated, and at the same time, the acceleration deviation compensation information is generated and transmitted to the steering mechanism assembly, and the acceleration deviation is adjusted through the steering mechanism assembly.

[0062] Step S4: Perform straight-line deviation compensation processing on the generated deviation compensation analysis information, and the specific compensation processing method is as follows:

[0063] The original image collected by the vehicle-mounted camera is denoised and distortion-corrected, and then the candidate lane line area is extracted through threshold segmentation (such as lane line feature extraction based on color space, such as white / yellow marking recognition in HSL / HSV space) or edge detection algorithm (Canny operator);

[0064] The lane line pixel coordinates in the image coordinate system are converted into physical coordinates (X, Y) in the vehicle coordinate system through the Homography Matrix, and the relative position relationship between the vehicle and the lane line is established (such as the lateral offset d of the lane center line and the heading angle deviation θ). The signal of the steering wheel angle sensor is monitored in real time to determine that the steering wheel is in the state of "near zero position", and at the same time, the lateral offset threshold d th and the heading angle deviation threshold θ th are set. The lateral offset threshold is based on the lane center line, and the allowable maximum lateral offset range is set (such as ±0.3 m, corresponding to the vehicle deviating from the lane center by no more than half of the vehicle body width). The heading angle deviation threshold is that the included angle between the vehicle driving direction and the lane line direction exceeds the set value (such as ±1.5°, reflecting the trend of the vehicle continuously deviating to one side), and the two are judged comprehensively;

[0065] If |d| > d th and |θ| > θ th and it lasts for a time t > t th where the value of t th is set by the operator, it is determined that it is a continuous straight-line deviation caused by abnormal positioning parameters, and at the same time, the straight-line deviation compensation information is generated;

[0066] Then, perform active steering deviation analysis on the generated straight-line deviation compensation information, and detect the steering wheel torque T applied by the driver through the torque sensor sw , and the obtained steering wheel torque T sw is compared with the steering wheel torque threshold T th . If T sw > T th, a steering to-be-analyzed signal is generated, and comprehensive analysis is performed in combination with the turn signal status. If it is detected that the turn signal is on (such as the left / right turn signal is activated), it indicates that the vehicle may be changing lanes, and the deviation determination is not triggered, and normal detection information is generated. On the contrary, if it is detected that the turn signal is not on, deviation detection compensation information is generated;

[0067] Analyze the obtained deviation detection compensation information, obtain the distances between the vehicle and the two sides of the current lane line through the on-vehicle camera, and record them as D l and D R , where D l represents the distance from the left lane line, and D R represents the distance from the right lane line. At the same time, compare D l and D R . If D l >D R , it indicates that the vehicle has a right deviation, and a right deviation signal is generated. On the contrary, if D l <D R , it indicates that the vehicle has a left deviation, and a left deviation signal is generated. Then, analyze the two respectively;

[0068] Establish a coordinate system with the midpoint of the lateral distance of the lane line as the origin, and here the origin corresponds to the vehicle in real time, which means that the reference point of the vehicle is the origin. Then calculate the distance difference between D l and D R , and use the obtained distance difference D c as the adjustment standard, and at the same time combine the generated left deviation signal or left deviation signal for reverse adjustment. The specific reverse adjustment method is as follows:

[0069] Analyze the adjustment angle and adjustment distance, determine the proportional relationship between the two, and calculate the compensation rotation angle δ comp =-K p ·D c according to the formula. Among them, K comp is the proportional gain, which specifically needs to be calibrated through actual vehicle testing. To avoid overshoot, set the maximum value of the compensation rotation angle δ p =±3°, and generate parameter deviation compensation information with the calculated compensation rotation angle δ comp as the standard; comp

[0070] Adjust through the steering structure and memorize it in the corresponding controller. The controller records the Dc value, compensation rotation angle δ comp and vehicle speed compensated each time in real time, and forms a "deviation amount - compensation amount" mapping table as shown in the following table:

[0071] ​

[0072] Step S5: Transmit the generated crosswind deviation compensation information, acceleration deviation compensation information, and parameter deviation compensation information to the steering mechanism assembly, and generate corresponding execution instructions through the steering mechanism to compensate and adjust the deviation of the entire vehicle.

[0073] Through the full-chain technological innovation of "multi-source data fusion + accurate cause identification + dynamic algorithm compensation + mechanical autonomous adjustment", the bottlenecks of traditional deviation compensation, such as relying on manual intervention, lagging response, and single scenario, have been broken through, realizing the intelligent and adaptive processing of vehicle deviation. Especially under complex working conditions (such as high-speed crosswind and heavy-load acceleration), the driving stability and safety are significantly improved, with engineering practicability and cost advantages.

[0074] For some data in the above formula, only their numerical values are taken for calculation, and the parameter units are not substituted for calculation. At the same time, the content not described in detail in this specification belongs to the prior art well-known to those skilled in the art.

[0075] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical method of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A vehicle deviation compensation method based on steer-by-wire, characterized in that The method specifically includes the following steps: Compare the vehicle driving state signal with a preset deviation adjustment to generate crosswind deviation, acceleration deviation, and straight-line deviation; Perform compensation processing on the crosswind deviation, calculate the aerodynamic side force according to the formula, calculate the desired yaw rate in combination with the vehicle dynamics model, calculate the total compensation torque through the PID control algorithm, and generate crosswind deviation compensation information; Perform compensation processing on the acceleration deviation, calculate the ideal yaw rate and the ideal lateral angular velocity according to the vehicle linear two-degree-of-freedom model, calculate the difference between the two and the corresponding threshold at the same time, and judge whether it is acceleration deviation according to the difference; For the analysis of acceleration deviation, calculate through the PID control algorithm, calculate and sum the proportional link, integral link, and differential link respectively to obtain the compensation control amount, and generate acceleration deviation compensation information; Perform compensation processing on the straight-line deviation, calculate the difference between the lateral offset and the heading angle deviation and the corresponding threshold, comprehensively determine the straight-line deviation based on the two, and further determine it in combination with the steering wheel torque and the turn signal on state to generate deviation detection compensation information; Analyze the deviation detection compensation information, calculate the distances on the left and right sides of the vehicle, compare the magnitudes of the two to generate a left or right deviation signal, and at the same time calculate the difference between the two and calculate the compensation angle to generate parameter deviation compensation information.

2. The vehicle deviation compensation method based on steer-by-wire according to claim 1, wherein The specific method for generating crosswind deviation, acceleration deviation, and straight-line deviation is as follows: Collect the vehicle speed, yaw rate, steering wheel angle, and steering gear position, compare with the preset deviation conditions. If all conditions are met, it is determined that the vehicle is not deviated, and normal monitoring information is generated. If any signal does not meet the conditions, it is determined that the vehicle is deviated, and deviation analysis information is generated. The compensation types include crosswind, acceleration, and straight-line deviation.

3. The vehicle deviation compensation method based on steer-by-wire according to claim 1, wherein The specific method for performing compensation processing on the crosswind deviation is as follows: According to the formula the aerodynamic side force F corresponding to the vehicle is calculated y , where ρ is the air density, C y is the side force coefficient, A is the frontal area of the vehicle, and V wind is the crosswind speed of the vehicle; According to the formula M z =F y ·h cg Calculate the vehicle yaw moment M z , where h cg is the height of the vehicle's center of mass, and the driver's steering wheel angle δ and real-time vehicle speed v are obtained at the same time. The vehicle dynamics model is used Calculate the desired yaw rate ω des , where L is the vehicle wheelbase, K is the vehicle stability factor, and the yaw rate deviation Δω = ω dse -ω act , where ω act is the actual yaw angular velocity.

4. The vehicle deviation compensation method based on steer-by-wire according to claim 1, characterized in that The specific method for generating crosswind deviation compensation information is as follows: Introduce a proportional link, M comp-p = K p ·Δω where K p is the proportionality coefficient; Introduce the integral link M comp-i = K i ∫Δωdt, where K i is the integral coefficient; Introduce a differentiating link where K d is the differentiation coefficient; Sum up the three to obtain the total compensation torque M comp = M comp-p + M comp-i + M comp-d , and generate crosswind deviation compensation information based on the total compensation torque as the standard.

5. The vehicle deviation compensation method based on steer-by-wire according to claim 1, wherein The specific method for performing compensation processing on the acceleration deviation is as follows: Based on the vehicle linear two-degree-of-freedom model Calculate the ideal yaw rate ω of the vehicle r-ideal , where δ is the steering wheel angle and v is the real-time vehicle speed. At the same time, according to the formula a y-ideal = v·ω e-ideal Calculate the ideal lateral acceleration a y-ideal ; Set the yaw rate deviation threshold Δω r-thershold and the lateral acceleration deviation threshold Δa y-threshold , calculate the deviation between the actual and ideal values, Δω r = |ω r-actual - ω r-ideal |, where ω r-actual is the actual yaw rate, Δa y = |a y-actual - a y-ideal |, where a y-ideal is the actual lateral acceleration; If Δω r > Δω r-threshold and Δa y > Δa y-threshold , or a single deviation exceeds the threshold and persists for a certain period of time, it is determined as instantaneous deviation, and acceleration deviation compensation information is generated.

6. The vehicle deviation compensation method based on steer-by-wire according to claim 1, wherein The specific method for generating acceleration deviation compensation information is as follows: Calculation of the comparative proportion link, u p = K p ·Δω r , where K p is the proportionality coefficient; For the calculation of the integral link, u i = K i ·Δω r , where K i is the integral coefficient; For the calculation of the differential link, u d = K d ·Δω r , where K d is the differential coefficient; According to the formula u = u p + u i + u d The total compensation control amount is calculated, and at the same time, the acceleration deviation compensation information is generated.

7. The vehicle deviation compensation method based on steer-by-wire according to claim 1, wherein The specific method for performing compensation processing on the straight-line deviation is as follows: After the in-vehicle camera collects the image, extract the lane line candidate area through threshold segmentation or edge detection, convert it into the physical coordinates of the vehicle coordinate system using the homography matrix, calculate the lateral offset d and the heading angle deviation θ, and at the same time monitor whether the steering wheel angle is near the "zero position"; Set the lateral offset threshold d th and the heading angle deviation threshold θ th , if |d| > d th and |θ| > θ th , and the duration t > t th , it is determined that the straight - path deviation is caused by abnormal positioning, and the straight - path deviation compensation information is generated; Detect the steering wheel torque T through a torque sensor sw , if T sw >T th or the turn signal is detected to be on, it is determined that the driver is operating actively and no compensation is triggered. Otherwise, deviation detection compensation information is generated.

8. The vehicle deviation compensation method based on steer-by-wire according to claim 1, characterized in that The specific method for analyzing the deviation detection compensation information is as follows: Obtain the distances D between the vehicle and the left and right lane lines through the on-vehicle camera L and D R If D L >D R It is determined that the vehicle is running off to the right, and a right running-off signal is generated. If D L <D R It is determined that the vehicle is running off to the left, and a left running-off signal is generated; Taking the midpoint of the lane width in the transverse direction as the origin, calculate the distance difference D c = D R - D L , combine with the generated deviation signal for reverse adjustment, and calculate the compensation angle δ according to the proportional relationship comp = -K p ·D c , where K p is the proportional gain, and generate the parameter deviation compensation information based on this

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