A method and device for steer-by-wire auxiliary braking

Abstract

This invention provides a steer-by-wire-assisted braking method and device, solving the problem of short-distance vehicle braking that cannot be achieved in existing technologies. Based on the separation state between the steering wheel and steering wheels in a linear steering system, and combining feedforward control and PID control algorithms, short-distance braking of the vehicle is achieved for different driving conditions. This effectively reduces driving risks, improves vehicle safety, reduces accident rates, and ensures good handling stability, driving smoothness, and vehicle safety during driving.

Description

Technical Field

[0001] This invention relates to the field of vehicle steering technology, and in particular to a steer-by-wire auxiliary braking method and device. Background Technology

[0002] With the development and innovation of autonomous driving technology, the vehicle steering system is also constantly evolving. Steer-by-wire technology is at the forefront of the times. It is a necessary key technology for autonomous vehicles to achieve path tracking and obstacle avoidance. Steer-by-wire technology can improve the degree of control over the vehicle, bring greater driving freedom, and significantly improve the stability and safety of the vehicle.

[0003] Automotive steer-by-wire technology eliminates the mechanical connection between the steering wheel and the steering wheels, completely freeing it from the constraints of mechanical components. Instead, it uses electrical signals to connect the steering wheel and the steering wheels, achieving steering through electrical energy. Even though it differs significantly from traditional mechanical steering systems, steer-by-wire systems still retain the advantages of traditional steering systems. Using electrical energy for steering makes it easier to achieve, and it can even optimize angular transmission characteristics that are difficult to achieve with mechanical steering systems. In a steer-by-wire system, when the driver operates the car, sensors convert the received signals into electrical signals. Theoretically, any steering intention can be achieved without being restricted by mechanical mechanisms. Therefore, steer-by-wire is considered the most advanced steering system technology currently available.

[0004] Automotive braking technology has always been of paramount importance for vehicle safety. In traditional mechanical steering systems, the steering wheel and steering wheels are constantly coupled after being connected by mechanical components. If no safety measures are taken for vehicle braking through the brakes or other means, the braking distance of the vehicle cannot be shortened, because the traditional mechanical steering system itself does not have the function of shortening the braking distance.

[0005] In a steer-by-wire system, because there are no mechanical parts connecting the steering wheel and the steering wheels, they are always in a decoupled, or separated, state, and both have a high degree of freedom. If we call the steering wheel the "upward turning part" and the steering wheels the "downward turning part," when the car is moving, if braking is detected, the steer-by-wire power steering motor can be driven by a control algorithm to cause the tires to swing slightly left and right. That is, downward turning results in a slight sway, which increases the braking force and shortens the braking distance. Traditional mechanical steering systems cannot currently achieve this function. Summary of the Invention

[0006] This invention provides a steer-by-wire-assisted braking method and device to solve the problem that short-distance vehicle braking cannot be achieved in the prior art.

[0007] In a first aspect, the present invention provides a steer-by-wire assisted braking method, specifically comprising the following steps:

[0008] Step S1: Based on the vehicle's sensors, obtain the vehicle's current speed, longitudinal acceleration, ABS (Anti-lock Braking System) braking signal, yaw rate, and vehicle structural parameters;

[0009] Step S2: Based on the longitudinal acceleration and the ABS braking information, determine whether the vehicle is in a braking state. When the longitudinal acceleration is less than zero and the ABS braking signal flag is detected, the vehicle is in a braking state and step S3 is executed; otherwise, the vehicle is not in a braking state and the determination of whether the vehicle is in a braking state is re-evaluated.

[0010] Step S3: Based on the vehicle structure parameters, the vehicle's current speed, longitudinal acceleration, and yaw rate, and combined with the vehicle dynamics model, calculate the road surface parameters and the corrected speed, longitudinal acceleration, and yaw rate.

[0011] Step S4: Identify and judge the current driving conditions of the vehicle; calculate the steering angle amplitude and steering frequency that the front wheels need to compensate based on the road surface parameters and the corrected speed and longitudinal acceleration; calculate the steering yaw center that the front wheels need to compensate based on the corrected yaw rate and the vehicle's operating conditions.

[0012] Step S5: Based on the required steering angle amplitude, steering angle frequency, and steering angle oscillation center of the front wheels, the steering angle parameters of the vehicle's front wheels are controlled using a feedforward control algorithm and a PID control algorithm.

[0013] Preferably, in step S1, the vehicle speed, longitudinal acceleration, and yaw rate are collected by a vehicle speed sensor, a longitudinal acceleration sensor, and a yaw rate sensor, respectively.

[0014] Preferably, in step S1, the structural parameters of the vehicle include, but are not limited to, structural parameters such as vehicle weight and wheelbase.

[0015] Preferably, in step S3, the road surface parameters include, but are not limited to, road surface parameters such as the road surface adhesion coefficient.

[0016] Preferably, in step S3, the road surface parameters and the corrected speed, longitudinal acceleration and yaw rate are calculated by parameter estimation method based on the vehicle structure parameters, the vehicle's current speed, longitudinal acceleration and yaw rate, and the vehicle dynamics model.

[0017] More preferably, the parameter estimation method includes, but is not limited to, one or more of the following: least squares method, extended Kalman filter, unscented Kalman filter, particle filter, and adaptive filter.

[0018] Preferably, in step S4, the current driving condition of the vehicle is identified and judged based on the corrected speed, longitudinal acceleration and yaw rate. When the corrected speed, longitudinal acceleration and yaw rate are within the preset threshold range, the current driving condition of the vehicle is a straight driving condition; otherwise, the current driving condition of the vehicle is a turning driving condition.

[0019] In step S4, the calculation of the swing center is only related to the vehicle speed, yaw rate and longitudinal acceleration, and is not related to whether it is a steering or straight driving condition.

[0020] Preferably, in step S5, based on the required steering angle amplitude, steering frequency, and steering oscillation center of the front wheels, the steering angle parameters of the vehicle's front wheels are controlled using a feedforward control algorithm and a PID control algorithm. Specifically, this includes the following steps:

[0021] Step S501: Based on the required steering angle amplitude, steering frequency, and steering oscillation center of the front wheel, calculate and generate rack position control commands using feedforward control algorithm and PID control algorithm;

[0022] Step S502: Based on the rack position control command and the current actual rack position, calculate and form a rack speed control command using a feedforward control algorithm and a PID control algorithm;

[0023] Step S503: Based on the rack speed control command and the current actual rack speed, a torque control command is generated by calculating using a PID control algorithm;

[0024] Step S504: The torque control command is transmitted to the vehicle steering motor, and the vehicle steering motor controls the front wheel steering angle, steering frequency, and steering oscillation center.

[0025] Secondly, the present invention also provides a steer-by-wire auxiliary braking device, specifically comprising the following modules:

[0026] The data acquisition module is used to acquire the vehicle's current speed, longitudinal acceleration, ABS braking signal, yaw rate and vehicle structural parameters based on the vehicle's sensors.

[0027] The braking state detection module is used to determine whether the vehicle is in a braking state based on the longitudinal acceleration and the ABS braking information. When the longitudinal acceleration is less than zero and the ABS braking signal flag is detected, the vehicle is in a braking state and the steering angle parameter calculation module is executed; otherwise, the vehicle is not in a braking state and the determination of whether the vehicle is in a braking state is re-evaluated.

[0028] The parameter processing module is used to calculate the road surface parameters and the corrected speed, longitudinal acceleration and yaw rate based on the vehicle structure parameters, the current speed of the vehicle, the longitudinal acceleration and the yaw rate, and the vehicle dynamics model.

[0029] The compensation steering angle parameter calculation module identifies and judges the current driving conditions of the vehicle, and calculates the steering angle amplitude and steering angle frequency that the front wheels need to compensate based on the road surface parameters and the corrected speed and longitudinal acceleration; and calculates the steering angle oscillation center that the front wheels need to compensate based on the corrected yaw rate and the vehicle's operating conditions.

[0030] The brake compensation control module is used to control the steering angle parameters of the vehicle's front wheels based on the steering angle amplitude, steering angle frequency, and steering angle oscillation center that the front wheels need to compensate for, through a feedforward control algorithm and a PID control algorithm.

[0031] Preferably, in the data acquisition module, the vehicle speed, longitudinal acceleration, and yaw rate are acquired by a vehicle speed sensor, a longitudinal acceleration sensor, and a yaw rate sensor, respectively.

[0032] Preferably, in the data acquisition module, the structural parameters of the vehicle include, but are not limited to, structural parameters such as vehicle weight and wheelbase.

[0033] Preferably, in the parameter processing module, the road surface parameters include, but are not limited to, road surface parameters such as the road surface adhesion coefficient.

[0034] Preferably, in the parameter processing module, the road surface parameters and the corrected speed, longitudinal acceleration and yaw rate are calculated by parameter estimation method based on the vehicle structure parameters, the vehicle's current speed, longitudinal acceleration and yaw rate, and the vehicle dynamics model.

[0035] More preferably, the parameter estimation method includes, but is not limited to, one or more of the following: least squares method, extended Kalman filter, unscented Kalman filter, particle filter, and adaptive filter.

[0036] Preferably, in the compensation angle parameter calculation module, the current driving condition of the vehicle is identified and judged based on the corrected speed, longitudinal acceleration and yaw rate. When the corrected speed, longitudinal acceleration and yaw rate are within the preset threshold range, the current driving condition of the vehicle is a straight driving condition; otherwise, the current driving condition of the vehicle is a turning driving condition.

[0037] In the compensation angle parameter calculation module, the calculation of the sway center is only related to the vehicle speed, yaw rate and longitudinal acceleration, and is not related to whether it is a steering or straight driving condition.

[0038] Preferably, the braking compensation control module specifically includes the following sub-modules:

[0039] The first sub-module of brake compensation control is used to calculate and form rack position control commands based on the angle amplitude, angle frequency and angle swing center that the front wheel needs to compensate for, through feedforward control algorithm and PID control algorithm.

[0040] The second sub-module of braking compensation control is used to calculate and form a rack speed control command based on the rack position control command and the current actual rack position through a feedforward control algorithm and a PID control algorithm.

[0041] The third submodule of braking compensation control is used to calculate and form torque control commands based on the rack speed control command and the current actual rack speed using a PID control algorithm.

[0042] The fourth sub-module of brake compensation control is used to transmit the torque control command to the vehicle steering motor, and the vehicle steering motor completes the control of the front wheel steering angle amplitude, steering frequency and steering oscillation center.

[0043] Thirdly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a steer-by-wire auxiliary braking method as described in any one of the first aspects of this application.

[0044] Fourthly, the present invention also provides an electronic device, the electronic device comprising: a memory storing a computer program; and a processor communicatively connected to the memory, which, when the computer program is invoked, executes a steer-by-wire auxiliary braking method as described in any one of the first aspects of this application.

[0045] Compared with the prior art, the present invention has the following obvious and prominent substantive features and significant advantages:

[0046] This invention provides a steer-by-wire-assisted braking method and device, solving the problem of short-distance vehicle braking that cannot be achieved in existing technologies. Based on the separation state between the steering wheel and steering wheels in a linear steering system, and combining feedforward control and PID control algorithms, short-distance braking of the vehicle is achieved for different driving conditions. This effectively reduces driving risks, improves vehicle safety, reduces accident rates, and ensures good handling stability, driving smoothness, and vehicle safety during driving. Attached Figure Description

[0047] The accompanying drawings, which constitute a part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0048] Figure 1 This is a flowchart of a steer-by-wire auxiliary braking method according to a preferred embodiment of the present invention.

[0049] Figure 2 A diagram of a braking signal detection module according to an embodiment of this application is shown.

[0050] Figure 3 A schematic diagram of the steer-by-wire auxiliary braking control principle according to an embodiment of this application is shown.

[0051] Figure 4 This is a schematic diagram of a steer-by-wire auxiliary braking device according to a preferred embodiment of the present invention. Detailed Implementation

[0052] This invention provides a method and apparatus for steer-by-wire auxiliary braking. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0053] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be used interchangeably where appropriate. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or apparatuses.

[0054] Example 1:

[0055] like Figures 1-3 As shown in the figure, the steer-by-wire auxiliary braking method described in this embodiment specifically includes the following steps:

[0056] Step S1: Based on the vehicle's sensors, acquire the vehicle's current speed, longitudinal acceleration, ABS braking signal, yaw rate, and vehicle structural parameters; wherein, the vehicle speed, longitudinal acceleration, and yaw rate are acquired by a vehicle speed sensor, a longitudinal acceleration sensor, and a yaw rate sensor, respectively; the vehicle structural parameters include, but are not limited to, structural parameters such as vehicle weight and wheelbase.

[0057] Step S2: Based on the longitudinal acceleration and the ABS braking information, determine whether the vehicle is in a braking state. When the longitudinal acceleration is less than zero and the ABS braking signal flag is detected, the vehicle is in a braking state and step S3 is executed; otherwise, the vehicle is not in a braking state and the determination of whether the vehicle is in a braking state is re-executed.

[0058] Step S3: Based on the vehicle structure parameters, the vehicle's current speed, longitudinal acceleration, and yaw rate, and combined with the vehicle dynamics model, calculate the road surface parameters and the corrected speed, longitudinal acceleration, and yaw rate; wherein, the road surface parameters include, but are not limited to, road surface adhesion coefficient and other road surface parameters.

[0059] The road surface parameters, as well as the corrected velocity, longitudinal acceleration, and yaw rate, are calculated using parameter estimation methods. These parameter estimation methods include, but are not limited to, one or more of the following: least squares method, extended Kalman filter, unscented Kalman filter, particle filter, and adaptive filter.

[0060] Step S4: Identify and judge the current driving conditions of the vehicle. Based on the road surface parameters and the corrected speed and longitudinal acceleration, calculate the angle amplitude and angle frequency that the front wheels need to compensate for. Based on the corrected yaw rate and the vehicle's operating conditions, calculate the angle swing center that the front wheels need to compensate for.

[0061] Specifically, the vehicle's current driving condition is identified and judged based on the corrected speed, longitudinal acceleration, and yaw rate. When the corrected speed, longitudinal acceleration, and yaw rate are within a preset threshold range, the vehicle's current driving condition is straight-line driving; otherwise, the vehicle's current driving condition is turning. The calculation of the yaw center is only related to the vehicle speed, yaw rate, and longitudinal acceleration, and is independent of whether it is a turning or straight-line driving condition.

[0062] Step S5: Based on the required steering angle amplitude, steering angle frequency, and steering angle oscillation center of the front wheels, the steering angle parameters of the vehicle's front wheels are controlled using a feedforward control algorithm and a PID control algorithm.

[0063] Optionally, in step S5, based on the required steering angle amplitude, steering frequency, and steering oscillation center of the front wheels, the steering angle parameters of the vehicle's front wheels are controlled using a feedforward control algorithm and a PID control algorithm. Specifically, this includes the following steps:

[0064] Step S501: Based on the required steering angle amplitude, steering frequency, and steering oscillation center of the front wheel, calculate and generate rack position control commands using feedforward control algorithm and PID control algorithm.

[0065] Step S502: Based on the rack position control command and the current actual rack position, calculate and form the rack speed control command through the feedforward control algorithm and the PID control algorithm.

[0066] Step S503: Based on the rack speed control command and the current actual rack speed, a torque control command is generated by calculating using a PID control algorithm.

[0067] Step S504: The torque control command is transmitted to the vehicle steering motor, and the vehicle steering motor controls the front wheel steering angle, steering frequency, and steering oscillation center.

[0068] First, the vehicle's driving conditions are identified, which can be broadly divided into two types: straight-line driving and turning driving. When the front wheel angle, yaw rate, and lateral acceleration are within the threshold range, the vehicle is in straight-line driving condition; when the steering wheel angle, yaw rate, and lateral acceleration exceed the set threshold, the vehicle is in turning driving condition.

[0069] When the vehicle is traveling straight, once a braking signal is detected, the vehicle will be subjected to braking force in the opposite direction of the vehicle's straight-line direction. At this time, the steer-by-wire system responds to the braking signal, calculates the angle amplitude and angle frequency that the front wheels need to compensate for based on the current longitudinal acceleration, vehicle speed, and road surface parameters, and calculates the angle oscillation center that the front wheels need to compensate for based on the yaw rate and the current operating conditions of the vehicle.

[0070] When a vehicle is turning, such as turning right, once a braking signal is detected, the vehicle experiences two directional forces: a lateral braking force to the left and a longitudinal braking force to the rear, which combine to form a resultant braking force in the left-rear direction, reducing the yaw rate. At this time, the steer-by-wire system responds to the braking signal, calculates the required steering angle amplitude and frequency for the front wheels based on the current longitudinal acceleration, vehicle speed, and road surface parameters, and calculates the required steering oscillation center for the front wheels based on the yaw rate and the current vehicle condition.

[0071] When the vehicle is traveling straight or turning, the required braking amplitude, steering frequency, and steering oscillation center of the front wheels are determined based on vehicle speed, longitudinal acceleration, and yaw rate. By employing feedforward control and PID control algorithms, the power steering motor of the drive-by-wire system controls the front wheel steering angle to compensate for braking. The left-right oscillation of the tires increases the resistance to straight-line travel, acting as a damping effect. The vehicle receives increased braking force, thus shortening the braking distance.

[0072] Example 2:

[0073] like Figure 4 As shown in the figure, the steer-by-wire auxiliary braking device described in this embodiment specifically includes the following modules:

[0074] The data acquisition module is used to acquire the vehicle's current speed, longitudinal acceleration, ABS braking signal, yaw rate, and vehicle structural parameters based on the vehicle's sensors. The vehicle speed, longitudinal acceleration, and yaw rate are acquired by a vehicle speed sensor, a longitudinal acceleration sensor, and a yaw rate sensor, respectively. The vehicle's structural parameters include, but are not limited to, structural parameters such as vehicle weight and wheelbase.

[0075] The braking state detection module is used to determine whether the vehicle is in a braking state based on the longitudinal acceleration and the ABS braking information. When the longitudinal acceleration is less than zero and the ABS braking signal flag is detected, the vehicle is in a braking state and the steering angle parameter calculation module is executed; otherwise, the vehicle is not in a braking state and the determination of whether the vehicle is in a braking state is re-evaluated.

[0076] The parameter processing module is used to calculate the road surface parameters and the corrected speed, longitudinal acceleration and yaw rate based on the vehicle structure parameters, the current speed of the vehicle, the longitudinal acceleration and the yaw rate, and the vehicle dynamics model; preferably, the road surface parameters in the parameter processing module include, but are not limited to, road surface parameters such as the road surface adhesion coefficient.

[0077] Specifically, based on the vehicle structural parameters, the vehicle's current speed, longitudinal acceleration, and yaw rate, and combined with the vehicle dynamics model, the road surface parameters and the corrected speed, longitudinal acceleration, and yaw rate are calculated using parameter estimation methods; the parameter estimation methods include, but are not limited to, one or more of the following: least squares method, extended Kalman filter, unscented Kalman filter, particle filter, and adaptive filter.

[0078] The compensation steering angle parameter calculation module identifies and judges the current driving conditions of the vehicle, and calculates the steering angle amplitude and steering angle frequency that the front wheels need to compensate based on the road surface parameters and the corrected speed and longitudinal acceleration; and calculates the steering angle oscillation center that the front wheels need to compensate based on the corrected yaw rate and the vehicle's operating conditions.

[0079] The vehicle's current driving condition is identified and judged based on the corrected speed, longitudinal acceleration, and yaw rate. When the corrected speed, longitudinal acceleration, and yaw rate are within the preset threshold range, the vehicle's current driving condition is straight driving; otherwise, the vehicle's current driving condition is turning. The calculation of the sway center is only related to the vehicle speed, yaw rate, and longitudinal acceleration, and is not related to whether it is a turning or straight driving condition.

[0080] The brake compensation control module is used to control the steering angle parameters of the vehicle's front wheels based on the steering angle amplitude, steering angle frequency, and steering angle oscillation center that the front wheels need to compensate for, through a feedforward control algorithm and a PID control algorithm.

[0081] The braking compensation control module specifically includes the following sub-modules:

[0082] The first submodule of brake compensation control is used to calculate and generate rack position control commands based on the angle amplitude, angle frequency and angle swing center of the front wheel that need to be compensated, through feedforward control algorithm and PID control algorithm.

[0083] The second submodule of braking compensation control is used to calculate and form rack speed control commands based on the rack position control command and the current actual rack position through feedforward control algorithm and PID control algorithm.

[0084] The third submodule of braking compensation control is used to calculate and form torque control commands based on the rack speed control command and the current actual rack speed using a PID control algorithm.

[0085] The fourth sub-module of brake compensation control is used to transmit the torque control command to the vehicle steering motor, and the vehicle steering motor completes the control of the front wheel steering angle amplitude, steering frequency and steering oscillation center.

[0086] The specific embodiments of the present invention have been described in detail above, but they are merely examples, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions to the present invention are also within the scope of the present invention. Therefore, all equivalent transformations and modifications made without departing from the spirit and scope of the present invention should be covered within the scope of the present invention.

Claims

1. A steer-by-wire auxiliary braking method, characterized in that, Specifically, the steps include the following: Step S1: Based on the vehicle's sensors, obtain the vehicle's current speed, longitudinal acceleration, ABS braking signal, yaw rate, and vehicle structural parameters. Step S2: Based on the longitudinal acceleration and the ABS braking information, determine whether the vehicle is in a braking state. When the longitudinal acceleration is less than zero and the ABS braking signal flag is detected, the vehicle is in a braking state and step S3 is executed. Conversely, if the vehicle is not in a braking state, the assessment of whether the vehicle is in a braking state is re-evaluated. Step S3: Based on the vehicle structure parameters, the vehicle's current speed, longitudinal acceleration, and yaw rate, and combined with the vehicle dynamics model, calculate the road surface parameters and the corrected speed, longitudinal acceleration, and yaw rate. Step S4: Identify and judge the current driving conditions of the vehicle; calculate the steering angle amplitude and steering frequency that the front wheels need to compensate based on the road surface parameters and the corrected speed and longitudinal acceleration; calculate the steering yaw center that the front wheels need to compensate based on the corrected yaw rate and the vehicle's operating conditions. Step S5: Based on the required steering angle amplitude, steering angle frequency, and steering angle oscillation center of the front wheels, the steering angle parameters of the vehicle's front wheels are controlled using a feedforward control algorithm and a PID control algorithm.

2. The steer-by-wire auxiliary braking method according to claim 1, characterized in that, In step S1, the vehicle speed, longitudinal acceleration, and yaw rate are collected by the vehicle speed sensor, longitudinal acceleration sensor, and yaw rate sensor, respectively.

3. The steer-by-wire auxiliary braking method according to claim 1, characterized in that, In step S1, the structural parameters of the vehicle include, but are not limited to, vehicle weight and wheelbase.

4. The steer-by-wire auxiliary braking method according to claim 1, characterized in that, In step S3, the road surface parameters include, but are not limited to, the road surface adhesion coefficient; based on the vehicle structure parameters, the vehicle's current speed, longitudinal acceleration, and yaw rate, and combined with the vehicle dynamics model, the road surface parameters and the corrected speed, longitudinal acceleration, and yaw rate are calculated using the parameter estimation method.

5. The steer-by-wire auxiliary braking method according to claim 4, characterized in that, The parameter estimation methods include, but are not limited to, one or more of the following: least squares method, extended Kalman filter, unscented Kalman filter, particle filter, and adaptive filter.

6. The steer-by-wire auxiliary braking method according to claim 1, characterized in that, In step S4, the current driving condition of the vehicle is identified and judged based on the corrected speed, longitudinal acceleration and yaw rate. If the corrected speed, longitudinal acceleration and yaw rate are within the preset threshold range, the current driving condition of the vehicle is straight driving condition; otherwise, the current driving condition of the vehicle is turning driving condition.

7. The steer-by-wire auxiliary braking method according to claim 1, characterized in that, In step S5, based on the required steering angle amplitude, steering frequency, and steering oscillation center of the front wheels, the steering angle parameters of the vehicle's front wheels are controlled using a feedforward control algorithm and a PID control algorithm. Specifically, this includes the following steps: Step S501: Based on the required steering angle amplitude, steering frequency, and steering oscillation center of the front wheel, calculate and generate rack position control commands using feedforward control algorithm and PID control algorithm; Step S502: Based on the rack position control command and the current actual rack position, calculate and form a rack speed control command using a feedforward control algorithm and a PID control algorithm; Step S503: Based on the rack speed control command and the current actual rack speed, a torque control command is generated by calculating using a PID control algorithm; Step S504: The torque control command is transmitted to the vehicle steering motor, and the vehicle steering motor controls the front wheel steering angle, steering frequency, and steering oscillation center.

8. A steer-by-wire auxiliary braking device, characterized in that, Specifically, it includes the following modules: The data acquisition module is used to acquire the vehicle's current speed, longitudinal acceleration, ABS braking signal, yaw rate and vehicle structural parameters based on the vehicle's sensors. The braking state detection module is used to determine whether the vehicle is in a braking state based on the longitudinal acceleration and the ABS braking information. When the longitudinal acceleration is less than zero and the ABS braking signal flag is detected, the vehicle is in a braking state and the steering angle parameter calculation module is executed; otherwise, the vehicle is not in a braking state and the determination of whether the vehicle is in a braking state is re-evaluated. The parameter processing module is used to calculate the road surface parameters and the corrected speed, longitudinal acceleration and yaw rate based on the vehicle structure parameters, the current speed of the vehicle, the longitudinal acceleration and the yaw rate, and the vehicle dynamics model. The compensation steering angle parameter calculation module identifies and judges the current driving conditions of the vehicle, and calculates the steering angle amplitude and steering angle frequency that the front wheels need to compensate based on the road surface parameters and the corrected speed and longitudinal acceleration; and calculates the steering angle oscillation center that the front wheels need to compensate based on the corrected yaw rate and the vehicle's operating conditions. The brake compensation control module is used to control the steering angle parameters of the vehicle's front wheels based on the steering angle amplitude, steering angle frequency, and steering angle oscillation center that the front wheels need to compensate for, through a feedforward control algorithm and a PID control algorithm.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements a steer-by-wire auxiliary braking method as described in any one of claims 1-7.

10. An electronic device, characterized in that, It includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements a steer-by-wire auxiliary braking method as described in any one of claims 1-7.

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