Steer-by-wire infinitely variable control method and controller

Abstract

The application discloses a kind of steer-by-wire stepless control methods, comprising: S1, define stepless hand feeling request request interval;S2, according to the stepless hand feeling request value obtained by driver input rack force feedback stepless coefficient, return stepless coefficient, damping stepless coefficient;S3, to the real-time real rack force low-pass filter of lower rotation is obtained Low-frequency road force, and it is weighted according to rack force stepless coefficient with virtual rack force;Extract real rack force fine road feeling component, and distribute weight according to stepless road feeling request;S4, combined with vehicle speed, steering wheel rotation angle Calculation stepless weighted return force;Combined with steering wheel speed, vehicle speed Calculation stepless weighted damping force;S5, superimposed weighted rack force feedback output, fine road feeling output, return force, damping force, the output of other hand feeling module, obtain original total request hand torque;S6, function safety constraint: to each single hand feeling module output, original total request hand torque carries out amplitude, slope dual limit value, obtains final total request hand torque.

Description

Technical Field

[0001] This invention relates to the automotive field, and in particular to a method and controller for continuously variable steering (CVT). Background Technology

[0002] This invention belongs to the field of automotive steer-by-wire control technology, specifically relating to a steer-by-wire control algorithm and steer-by-wire hardware system that integrates stepless feel simulation and stepless transmission ratio adjustment.

[0003] The steer-by-wire system consists of three main parts: the upper steering mechanism, the lower steering mechanism, and the controller. The steering mechanism consists of a steering wheel, a reduction mechanism, and a hand-feel motor. It is used to collect the driver's steering wheel operation signals and receive controller instructions to simulate road feel feedback to the driver's hands. The downward turning mechanism consists of a steering motor, a reduction mechanism, and a wheel rack assembly. It receives the steering angle command from the controller to drive the wheels to complete the steering, and at the same time collects the real rack force feedback to the controller in real time. Controller: It has a built-in stepless hand feel control module, stepless transmission ratio control module, and amplitude and slope limit module. It calculates the hand feel torque and the target wheel angle in a coordinated manner, drives the hand feel motor and the down-turn steering motor respectively, and executes torque amplitude and slope safety constraints at the same time.

[0004] The steering mechanism and the lower steering mechanism are not connected by a mechanical intermediate shaft, so road disturbances cannot be directly transmitted to the steering wheel. Instead, a hand-feel motor is needed to simulate road feel feedback. Existing steer-by-wire technology has two core flaws: 1) Fixed feel simulation mode, unable to be infinitely personalized: Existing feel simulations are divided into two rack force generation schemes: Scheme 1 uses virtual rack force, which provides rich road feel but cannot reproduce the real road surface condition; Scheme 2 uses real rack force in real time during downshifting, which provides a realistic road feel but the road feel performance is monotonous. Traditional schemes only have fixed overlays of rack force feedback, return to center, damping and other feel modules, which cannot be infinitely adjusted according to the driver's needs for feel weight; at the same time, the intensity of the extracted minor road surface feel is fixed, and the driver cannot adjust the amplitude of the feedback of minor bumps, but can only use the manufacturer's preset fixed feel, which cannot adapt to the needs of people with different driving styles.

[0005] 2) Fixed steering ratio gears, unable to be continuously and steplessly adjusted: The existing steer-by-wire gear ratio is only set with a few fixed gears (small gear ratio mode, normal mode), and the gear ratio cannot be continuously changed; steering flexibility and driving stability cannot be smoothly switched at different vehicle speeds, and the driver cannot customize the steering stroke. Low-speed steering flexibility and high-speed driving stability cannot be adjusted in a personalized way.

[0006] 3) Existing technologies have not achieved integrated and coordinated control of continuously variable feel and continuously variable transmission ratio. The two sets of control logics are independent of each other and cannot be uniformly adapted to the driver's customized driving needs. Summary of the Invention

[0007] The summary of this invention introduces a series of simplified concepts, all of which are simplifications of existing technologies in the field, and will be further explained in detail in the detailed description section. This summary is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0008] To address the technical problems of existing steer-by-wire systems, such as fixed and non-infinitely adjustable steering feel parameters, inability to customize the intensity of road surface texture, and fixed steering ratio that cannot be continuously and steplessly switched, thus failing to adapt to the personalized driving styles of different drivers, this invention provides a steer-by-wire stepless control method and controller. This method enables continuous and stepless customization of steering feel, intensity of road surface texture, and steering ratio, and unifies and coordinates the control of steering feel simulation and steering ratio, balancing low-speed steering agility and high-speed driving stability to meet the driving needs of all types of drivers.

[0009] To solve the above-mentioned technical problems, the present invention provides a continuously variable steering method for steer-by-wire, comprising the following steps: S1. Define the range of requests for stepless tactile feedback; S2. Obtain the rack force feedback stepless coefficient, return stepless coefficient, and damping stepless coefficient based on the stepless feel request value input by the driver; S3. Low-pass filter the real rack force in real time to obtain low-frequency road force, and weight it with virtual rack force according to rack force stepless coefficient; extract the fine road feel components of real rack force, and assign weights according to stepless road feel requirements. S4. Calculate the continuously weighted return force based on vehicle speed and steering wheel angle; calculate the continuously weighted damping force based on steering wheel speed and vehicle speed. S5. The weighted rack force feedback output, minor road feel output, return force, damping force, and other feel module outputs are superimposed to obtain the original total required hand torque; S6. Functional safety constraints: The output of each individual hand-feel module and the original total requested hand torque are subject to dual limits of amplitude and slope to obtain the final total requested hand torque.

[0010] Optionally, the described steer-by-wire continuously variable control method can be further improved by defining a continuously variable transmission ratio request range when executing step S1. S7. Output the upper soft stop travel angle according to the continuously variable transmission ratio request; combine the continuously variable transmission ratio request and vehicle speed to obtain the continuous continuously variable transmission ratio; multiply the steering wheel angle by the continuously variable transmission ratio to output the lower turn request angle. S8. Drive the hand feel motor to output simulated hand feel according to the final total requested hand torque, and drive the down turn steering motor to perform steering action according to the down turn requested angle.

[0011] Optionally, the described steer-by-wire stepless control method can be further improved by calculating the feedback stepless coefficient, the return stepless coefficient, and the damping stepless coefficient through offline table lookup or real-time formula.

[0012] Optionally, the described continuously variable steering method can be further improved, where there is no output of minor road feel when the road feel stepless coefficient is 0%, and the minor road feel component is fully output when the coefficient is 100%.

[0013] Optionally, the described steer-by-wire continuously variable control method can be further improved by specifying the transmission ratio and the soft stop point of the upper rotation according to the driver's continuously variable transmission ratio request of 0%-100%. Under the full range of continuously variable transmission ratio requests, the total downward rotation angle travel is fixed at 450°.

[0014] This invention provides a steer-by-wire controller, comprising: Stepless tactile control module, stepless transmission ratio control module, amplitude slope limit module; The continuously variable feel control module is used to receive the continuously variable feel request value input by the driver, calculate the continuously variable coefficient of each feel module; obtain the low-frequency road force by low-pass filtering the real rack force in real time during downshift, and weight it with the virtual rack force according to the continuously variable coefficient of rack force; extract the small road feel components of the real rack force, and assign weights according to the continuously variable road feel request; and superimpose the weighted rack force feedback output, return output, and damping output to obtain the original total requested hand torque. The continuously variable transmission ratio control module is used to receive the continuously variable transmission ratio request value input by the driver, and synchronously output the matching upward soft stop travel angle and the continuous continuously variable transmission ratio to ensure that the total downward turning angle travel is constant throughout the entire range; and calculates the downward turning request angle based on the steering wheel angle, current vehicle speed, and continuous continuously variable transmission ratio. The amplitude and slope limit module is used to impose dual limit constraints on the single output force and original total requested hand torque of each hand feel module, and output the final total requested hand torque. The vehicle controller is connected to the hand-feed motor and the down-turn steering motor by electrical signals. The vehicle controller drives the hand-feed motor according to the final total requested hand torque and drives the down-turn steering motor according to the requested down-turn angle.

[0015] Optionally, the steer-by-wire controller can be further improved by specifying the transmission ratio and the soft stop of the upper rotation based on the driver's continuously variable transmission ratio request. Under the full range of the continuously variable transmission ratio request, the total downward rotation angle is fixed at 450°. Optionally, the steer-by-wire controller can be further improved, wherein the continuously variable feel request of 0% corresponds to the minimum feel force, and the continuously variable feel request of 100% corresponds to the maximum feel force; the continuously variable road feel coefficient of 0% corresponds to no minor road feel output, and 100% corresponds to a complete output of 0.5Hz-20Hz minor road feel components.

[0016] Optionally, the steer-by-wire controller can be further improved by obtaining the stepless coefficients of each feel module by either looking up a table or calculating using a real-time formula.

[0017] Optionally, the steer-by-wire controller can be further improved, wherein the return-to-center output force of the continuously variable steering control module is calculated by combining the vehicle speed, steering wheel angle, and continuously variable return-to-center coefficient; and the damping output force is calculated by combining the steering wheel speed, vehicle speed, and continuously variable damping coefficient.

[0018] The working principle of the present invention is explained below based on the above technical solution; This invention allows the driver to input a continuously variable steering feel request and a continuously variable transmission ratio request within a range of 0%-100%. On one hand, it continuously weights the low-frequency force of the real rack, the virtual rack force, and the subtle road feel extracted by bandpass, and superimposes multiple modules of steering feel force such as return and damping, while setting safety limits, so as to achieve continuously adjustable steering wheel feel and subtle road feel intensity. On the other hand, it synchronously matches the continuously changing transmission ratio and the upper soft stop angle, and locks the lower total steering angle travel constant throughout the entire process, so as to achieve smooth shifting of steering transmission ratio without gears. The two sets of control logic are output by the vehicle controller to drive the steering feel motor and the lower steering motor to complete the steering feel simulation and wheel steering.

[0019] Based on the above technical solution and working principle, the present invention can achieve at least the following technical effects compared with the prior art; 1. Existing technologies only use a fixed single rack and pinion force superposition scheme, lacking a continuous adjustment mechanism. Furthermore, existing fixed-gear schemes cannot achieve continuous shifting of feel, failing to cater to the driving preferences of all users.

[0020] This invention sets the weight of real low-frequency road feel, virtual road feel, and minor bumpy road feel to be infinitely adjustable from 0% to 100%, which can adapt to the lightweight feel of female drivers and the sporty and heavy feel of professional drivers, realizing all-dimensional infinitely personalized feel adjustment.

[0021] 2. The intensity of high-frequency, fine bump feedback on the road surface is fixed at the factory in the existing technology, and the driver cannot turn off / amplify the fine road feel independently.

[0022] This invention extracts and independently weights the minor road feel components using a 0.5Hz-20Hz bandpass filter, allowing the driver to freely control the transmission amplitude of minor road bumps. The minor road feel is independently and steplessly adjustable, improving driving comfort.

[0023] 3. The transmission ratio can be continuously and smoothly adjusted steplessly. Existing technology only sets 2-3 fixed transmission ratios, and the switching feels abrupt.

[0024] This invention features a continuously varying transmission ratio between 0% and 100%. In the low-speed range, a large transmission ratio is matched to reduce steering wheel travel and improve agility. In the high-speed range, a small transmission ratio is matched to increase steering wheel travel and improve driving stability. The total steering angle remains unchanged throughout the entire range, and the steering limit remains unchanged, thus balancing agility and stability.

[0025] 4. Existing technologies lack a unified security constraint mechanism, posing potential security risks.

[0026] This invention achieves integrated and coordinated control of feel and transmission ratio, and unified adjustment based on the driver's custom request value. There is no need to set two separate sets of parameters, and the operation logic is simple. The output of each module increases the amplitude and slope safety limit to avoid the steering safety risks caused by sudden torque changes.

[0027] 5. Using virtual rack force alone cannot reproduce the bumps of a real road surface, and using real rack force alone results in a narrow range of adjustable road feel, making it difficult to strike a balance between realism and adjustability. This invention combines the two in a weighted manner, while also separating and independently adjusting the fine details of road feel, thus possessing both realistic road feel reproduction and a wide range of customizable adjustment capabilities. Attached Figure Description

[0028] The accompanying drawings are intended to illustrate the general characteristics of the methods, structures, and / or materials used in specific exemplary embodiments of the invention, supplementing the description in the specification. However, the drawings are schematic diagrams not drawn to scale and may not accurately reflect the precise structural or performance characteristics of any of the given embodiments. The drawings should not be construed as limiting or restricting the range of numerical values ​​or properties covered by exemplary embodiments of the invention. The invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0029] Figure 1 This is a schematic diagram of the hardware principle of steer-by-wire.

[0030] Figure 2 This is a schematic diagram of the control logic of the present invention. Figure 1 .

[0031] Figure 3 This is a schematic diagram of the control logic of the present invention. Figure 2 . Detailed Implementation

[0032] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can fully understand other advantages and technical effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through different specific embodiments, and various details in this specification can also be applied based on different viewpoints, with various modifications or changes made without departing from the overall design concept of the invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. The following exemplary embodiments of the present invention can be implemented in many different forms and should not be construed as being limited to the specific embodiments set forth herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the technical solutions of these exemplary embodiments to those skilled in the art. It should be understood that when an element is referred to as "connected" or "combined" to another element, the element can be directly connected or combined to the other element, or there may be intermediate elements. The difference is that when an element is referred to as "directly connected" or "directly combined" to another element, there are no intermediate elements. Throughout the drawings, the same reference numerals always denote the same elements.

[0033] First embodiment; First, it should be noted that all the tables mentioned in this embodiment can be obtained through calibration. This invention provides a continuously variable steering method, including: S1, preset adjustment range; The preset range for the stepless feel request is 0%~100%: 0% outputs the minimum feel force, and 100% outputs the maximum feel force. The preset continuously variable transmission ratio is requested to be in the range of 0% to 100%; for example, 0% corresponds to a maximum upward stroke of 150° and a transmission ratio of 3; 100% corresponds to an upward stroke of 450° and a transmission ratio of 1; under any requested value throughout the entire stroke, the total downward rotation angle is fixed at 450°.

[0034] S2, obtain the continuously variable feel request value input by the driver, and look up the table to obtain the continuously variable coefficient of rack force feedback, road feel, self-alignment and damping respectively; the table of continuously variable coefficient of rack force feedback, road feel and self-alignment and damping can be obtained through calibration. S3 collects the real-time rack force during downward rotation and processes it through two-channel filtering: A low-pass filter is used to extract the low-frequency real road force, which is then multiplied by the rack force feedback stepless coefficient. A 0.5Hz-20Hz bandpass filter is used to extract the subtle road feel components, which are then multiplied by a stepless road feel coefficient. A 0% stepless road feel coefficient means no subtle road feel is output, while a 100% stepless road feel coefficient means the subtle road feel is fully output. S4: Based on the current vehicle speed and steering wheel angle, look up the table to obtain the basic self-centering force, and multiply it by the self-centering stepless coefficient to obtain the stepless self-centering force; based on the steering wheel speed and vehicle speed, look up the table to obtain the basic damping force, and multiply it by the damping stepless coefficient to obtain the stepless damping force. The S5 combines low-frequency realistic road feel output, fine road feel output, continuously variable return force, continuously variable damping force, and output from other feel modules to obtain the original total required hand torque.

[0035] S6 performs amplitude and slope limit processing on the output of each individual hand-feel module and the original total requested hand torque to obtain the final total requested hand torque.

[0036] S7. Based on the continuously variable transmission ratio request, look up the table to output the matching upward soft dead center stroke angle; combine the continuously variable transmission ratio request value and the current vehicle speed to look up the table to output the continuous continuously variable transmission ratio; multiply the real-time collected steering wheel angle with the continuously variable transmission ratio to obtain the downward rotation request angle.

[0037] S8. The controller sends the final total requested torque to the hand feel motor to simulate the driver's steering wheel feel; it sends the down turn request angle to the down turn steering motor to drive the wheels to perform the steering action.

[0038] Alternatively, the first embodiment of the present invention can be further improved in the following ways: 1. The coefficients of each stepless coefficient can be obtained by either offline table lookup or real-time formula calculation, and the two methods are interchangeable; 2. The frequency band for filtering minor road feel is fixed at 0.5Hz-20Hz and is no longer adjustable; 3. Fixed basic travel parameters: the maximum travel of the upward rotation is 150° / 450°, and the total rotation angle of the downward rotation is constant at 450°. Second embodiment;

[0039] like Figure 1 As shown, the steering-by-wire hardware consists of three parts: an upper steering mechanism, a lower steering mechanism, and a controller. Upper steering mechanism: includes steering wheel, reduction mechanism, and hand feel motor; the driver operates the steering wheel, and the steering wheel torque and angle signals are transmitted to the vehicle controller; the vehicle controller outputs the total requested hand torque signal to the hand feel motor, and after the torque is amplified by the reduction mechanism, it outputs simulated road feel hand force to the steering wheel.

[0040] Downward turning mechanism: includes steering motor, reduction mechanism, wheel rack assembly; the vehicle controller outputs downward turning request angle signal to steering motor, the motor drives rack and wheel through reduction mechanism to complete steering action, and the downward turning mechanism collects real rack force in real time and feeds it back to vehicle controller.

[0041] This invention provides a steer-by-wire controller, which is divided into three main functional modules: a continuously variable feel control module, a continuously variable transmission ratio control module, and an amplitude and slope limit module.

[0042] The working logic of the continuously variable haptic control module is illustrated below: The driver inputs a continuously variable steering feel request value from 0% to 100%, which is then sent to the multiplication unit of each branch road. (1) Real rack force branch: The real rack force is filtered by low-pass filter to extract the low-frequency road force, and multiplied by the rack force feedback stepless coefficient obtained by looking up the table of stepless feel request to obtain the low-frequency real road feel output force; (2) Fine road feel branch: The real rack force is filtered by a 0.5Hz-20Hz bandpass filter to extract the fine bump component, which is multiplied by the stepless road feel coefficient to obtain the fine road feel output force; (3) Returning branch: Combine vehicle speed and steering wheel angle to find the basic returning force in the table, and multiply it by the continuously variable returning coefficient to get the continuously variable returning output force; (4) Damping branch: The basic damping force is obtained by referring to the table based on the steering wheel speed and vehicle speed, and multiplied by the stepless damping coefficient to obtain the stepless damping output force; (5) Weighted output of the remaining tactile function modules; The output of all branches is fed into the addition unit to be superimposed to obtain the original total requested hand torque, which is then sent to the amplitude and slope limit module for safety constraints, and finally output to drive the hand motor with the total requested hand torque.

[0043] The working logic of the continuously variable transmission ratio control module is illustrated below: The driver inputs a continuously variable transmission ratio (CVT) request value between 0% and 100%, which is then processed in two ways: (1) Soft stop control branch: The continuously variable transmission ratio is requested to be looked up from the table to output the soft stop stroke angle of the upper rotation; Data source: 0% corresponds to 150°, 100% corresponds to 450°; (2) Transmission ratio calculation branch: Combine the continuously variable transmission ratio request and the current vehicle speed to look up the table and output the continuous continuously variable transmission ratio; multiply the real-time steering wheel angle by the continuously variable transmission ratio and output the downward steering request angle; Parameter constraints: 0% gear ratio requires gear ratio 3, with an upward rotation of 150° and a total downward rotation angle of 150×3=450°; 100% gear ratio requires gear ratio 1, with an upward rotation of 450° and a total downward rotation angle of 450×1=450°; the total downward rotation angle is constant at 450° throughout the 0%-100% range.

[0044] Amplitude and slope limit module: limits the torque amplitude and torque change slope of each individual module of rack force feedback output, fine road feel output, return output, and damping output; at the same time, sets upper limits for amplitude and slope of the total requested torque after superposition to prevent sudden torque changes and meet functional safety specifications.

[0045] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It will also be understood that, unless explicitly defined herein, terms such as those defined in a general dictionary shall be interpreted as having the meaning consistent with their meaning in the relevant field context, and not as having an idealized or overly formal meaning.

[0046] The present invention has been described in detail above through specific embodiments and examples, but these are not intended to limit the invention. Many modifications and improvements can be made by those skilled in the art without departing from the principles of the invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. A method for continuously variable steering (CVT) of steer-by-wire, characterized in that, Includes the following steps: S1. Define the range of requests for stepless tactile feedback; S2. Obtain the rack force feedback stepless coefficient, return stepless coefficient, and damping stepless coefficient based on the stepless feel request value input by the driver; S3. Low-frequency road surface force is obtained by low-pass filtering of the real rack force in the down-turning real time, and weighted with virtual rack force according to rack force stepless coefficient; Extract the fine road feel components of the actual rack force and assign weights according to the continuously variable road feel requirements; S4. Calculate the continuously weighted return force based on vehicle speed and steering wheel angle; Calculate the continuously weighted damping force by combining steering wheel rotation speed and vehicle speed; S5. The weighted rack force feedback output, minor road feel output, return force, damping force, and other feel module outputs are superimposed to obtain the original total required hand torque; S6. Functional safety constraints: The output of each individual hand-feel module and the original total requested hand torque are subject to dual limits of amplitude and slope to obtain the final total requested hand torque.

2. The steer-by-wire stepless control method according to claim 1, characterized in that: When performing step S1, the continuously variable transmission ratio request range is also defined; S7. Output the upper soft stop travel angle according to the continuously variable transmission ratio request; combine the continuously variable transmission ratio request and vehicle speed to obtain the continuous continuously variable transmission ratio; multiply the steering wheel angle by the continuously variable transmission ratio to output the lower turn request angle. S8. Drive the hand feel motor to output simulated hand feel according to the final total requested hand torque, and drive the down turn steering motor to perform steering action according to the down turn requested angle.

3. The steer-by-wire stepless control method according to claim 2, characterized in that: The feedback stepless coefficient, the homing stepless coefficient, and the damping stepless coefficient are obtained by offline table lookup or real-time formula calculation.

4. The steer-by-wire stepless control method according to claim 2, characterized in that: When the stepless coefficient of road feel is 0%, there is no output of minor road feel; when it is 100%, the minor road feel components are output in their entirety.

5. The steer-by-wire stepless control method according to claim 2, characterized in that: Based on the driver's continuously variable transmission ratio request of 0%-100%, specify the transmission ratio and upper soft stop. Under the full range of continuously variable transmission ratio requests, the total downward rotation angle travel is fixed at 450°.

6. A steer-by-wire controller, characterized in that, include: Stepless tactile control module, stepless transmission ratio control module, amplitude slope limit module; The continuously variable feel control module is used to receive the continuously variable feel request value input by the driver and calculate the continuously variable coefficient of each feel module; Low-frequency road force is obtained by low-pass filtering of real rack force in real time and weighted with virtual rack force according to rack force stepless coefficient; fine road feel components of real rack force are extracted and weighted according to stepless road feel request. The rack force feedback output, return output, and damping output are superimposed and weighted to obtain the original total requested torque; The continuously variable transmission ratio control module is used to receive the continuously variable transmission ratio request value input by the driver and synchronously output the matching upward soft stop stroke angle and continuous continuously variable transmission ratio to ensure that the total downward rotation angle stroke is constant throughout the entire range. Calculate the required downward turn angle based on the steering wheel angle, current vehicle speed, and continuously variable transmission ratio; The amplitude and slope limit module is used to impose dual limit constraints on the single output force and original total requested hand torque of each hand feel module, and output the final total requested hand torque. The vehicle controller is connected to the hand-feed motor and the down-turn steering motor by electrical signals. The vehicle controller drives the hand-feed motor according to the final total requested hand torque and drives the down-turn steering motor according to the requested down-turn angle.

7. The steer-by-wire controller according to claim 6, characterized in that: The transmission ratio and upper soft stop are specified according to the driver's continuously variable transmission ratio request. Under the full range of continuously variable transmission ratio requests, the total downward rotation angle is fixed at 450°.

8. The steer-by-wire controller according to claim 6, characterized in that: The continuously variable feel request of 0% corresponds to the minimum feel force, and the continuously variable feel request of 100% corresponds to the maximum feel force. The stepless coefficient for road feel is 0% corresponding to no minor road feel output, and 100% corresponding to a complete output of minor road feel components from 0.5Hz to 20Hz.

9. The steer-by-wire controller according to claim 6, characterized in that: The continuously variable feel control module obtains the continuously variable coefficients of each feel module by either looking up a table or by calculating in real time using a formula.

10. The steer-by-wire controller according to claim 6, characterized in that: The return-to-center output force of the continuously variable steering control module is calculated by combining the vehicle speed, steering wheel angle, and continuously variable return-to-center coefficient; the damping output force is calculated by combining the steering wheel rotation speed, vehicle speed, and continuously variable damping coefficient.

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