Vehicle steering control method and device, electronic equipment and storage medium

Abstract

The invention provides a vehicle steering control method and device, electronic equipment and a storage medium, and belongs to the field of vehicle steering control. The method comprises the steps that a discretized vehicle state equation and a vehicle yaw velocity expectation are determined based on vehicle state parameters, and a vehicle steering control result is obtained based on the discretized vehicle yaw velocity and the vehicle yaw velocity expectation; a discrete sliding mode surface is constructed, and a front wheel steering angle control force output by a steering unit is determined through the discrete sliding mode surface and an exponential reaching law, so that the size of a front wheel steering angle is changed through the front wheel steering angle control force, front wheel steering is actively controlled through the discrete sliding mode surface, and smooth control over front wheel steering can be achieved. Buffeting caused by high-frequency switching can be effectively weakened, meanwhile, the high robustness of the system to interference is kept, and the stability of vehicle active front wheel steering control is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vehicle steering control, and particularly relates to a vehicle steering control method and device, an electronic device and a storage medium. BACKGROUND

[0002] Active front steering (AFS) dynamically adjusts the front wheel steering angle through an electronic control system, and is a research hotspot in the field of automobile engineering, aiming to compensate for the stability and safety of the vehicle in real time through the front wheel steering angle, especially in the case of high-speed turning of the vehicle, emergency collision avoidance, etc. The core principle of active front steering is to add an additional steering angle through a motor or planetary gear mechanism according to real-time data such as vehicle speed, steering wheel angle, yaw rate, etc., so as to optimize the steering transmission ratio. Active front steering can greatly improve the steering stability and safety of the vehicle under complex road conditions, load changes, etc. In the active front steering system, the control of the front wheel steering angle is often realized based on a sliding mode control algorithm. The sliding mode control algorithm has strong robustness to external disturbances and uncertainties of the system, but the sliding mode control itself has the disadvantage of high-frequency chattering, which may reduce the stability of the vehicle front wheel steering control. SUMMARY

[0003] Embodiments of the present application provide a vehicle steering control method, device, electronic device and storage medium, which can be used to improve the stability of vehicle front wheel steering control. The technical solution is as follows: In a first aspect, a vehicle steering control method is provided, and the method comprises: obtaining vehicle state parameters, the vehicle state parameters comprising a front wheel steering angle and a vehicle yaw rate; determining a discretized vehicle state equation and a vehicle yaw rate expectation based on the vehicle state parameters; constructing a sliding mode surface based on the discretized vehicle yaw rate in the discretized vehicle state equation and the vehicle yaw rate expectation; determining a front wheel steering angle control force of a steering unit output based on the sliding mode surface, the front wheel steering angle control force being used to change the size of the front wheel steering angle.

[0004] In a second aspect, a vehicle steering control device is provided, and the device comprises: a first obtaining module configured to obtain vehicle state parameters, the vehicle state parameters comprising a front wheel steering angle and a vehicle yaw rate; a second determining module configured to determine a discretized vehicle state equation and a vehicle yaw rate expectation based on the vehicle state parameters; a third constructing module configured to construct a sliding mode surface based on the discretized vehicle yaw rate in the discretized vehicle state equation and the vehicle yaw rate expectation; A fourth determining module is configured to determine a front wheel steering angle control force of the steering unit output based on the sliding mode surface, the front wheel steering angle control force being used to change the size of the front wheel steering angle.

[0005] In a third aspect, an electronic device is provided, which includes a processor and a memory storing programs or instructions executable on the processor, and the programs or instructions, when executed by the processor, implement the vehicle steering control method described above.

[0006] In a fourth aspect, a non-transitory computer-readable storage medium is also provided, which stores a computer program, and the computer program is loaded and executed by a processor to implement the vehicle steering control method described above.

[0007] The technical solutions provided in the present application at least have the following beneficial effects: The present application obtains vehicle state parameters, determines a discretized vehicle state equation and a vehicle yaw rate expectation based on the vehicle state parameters, constructs a discrete sliding mode surface based on the discretized vehicle yaw rate in the discretized vehicle state equation and the vehicle yaw rate expectation, determines a front wheel steering angle control force of the steering unit output through the discrete sliding mode surface, and changes the size of the front wheel steering angle through the front wheel steering angle control force. When the present application actively controls the front wheel steering through the discrete sliding mode surface, it can achieve smooth control of the front wheel steering, effectively weaken the buffeting caused by high-frequency switching, maintain strong robustness of the system to interference, improve the stability of the vehicle active front wheel steering control, make the vehicle front wheel steering quickly converge to the vehicle yaw rate expectation, significantly reduce steering delay, have better dynamic response capability and safety in emergency obstacle avoidance or low adhesion road surface scenarios, and accelerate the approach to the sliding mode surface when far away from the sliding mode surface, and automatically slow down when close to the sliding mode surface, which is conducive to the rapid convergence of the system and improves the real-time performance of the vehicle active front wheel steering control. BRIEF DESCRIPTION OF DRAWINGS

[0008] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0009] Figure 1 is one of the vehicle steering control method flowcharts provided by the embodiments of the present application; Figure 2 is a vehicle motion model schematic diagram provided by the embodiments of the present application; Figure 3 is another vehicle steering control method flowchart provided by the embodiments of the present application; Figure 4 is one of the simulation diagrams of the vehicle steering control method provided by the embodiment of the present application; Figure 5 is another simulation diagram of the vehicle steering control method provided by the embodiment of the present application; Figure 6 is a third simulation diagram of the vehicle steering control method provided by the embodiment of the present application; Figure 7 is a fourth simulation diagram of the vehicle steering control method provided by the embodiment of the present application; Figure 8 is a structural schematic diagram of the vehicle steering control device provided by the embodiment of the present application. DETAILED DESCRIPTION

[0010] In order to make the purpose, technical solutions and advantages of the present application clearer, the embodiment of the present application will be described in further detail below with reference to the drawings.

[0011] Figure 1 is a flowchart of the vehicle steering control method provided by the embodiment of the present application. The method can be applied to a vehicle steering system, which includes a steering control mechanism, a steering gear, a steering transmission mechanism, a controller and a sensor. The steering control mechanism is mainly composed of a steering wheel, a steering shaft, a steering column and the like. The driver transmits the steering force to the steering gear by rotating the steering wheel. The steering gear changes the rotation of the steering wheel into the swing of the steering arm or the linear reciprocating motion of the rack shaft, amplifies the steering control force and changes the transmission direction at the same time. The steering transmission mechanism transmits the force and motion output by the steering gear to the wheels and deflects the left and right wheels according to a certain relationship. It is mainly composed of a steering arm, a steering drag link, a steering knuckle arm and a steering trapezium. The sensor is used to obtain the vehicle state parameters. The vehicle body attitude sensor feeds back the driving state parameters such as vehicle lateral acceleration and yaw rate. The controller analyzes and calculates the data collected by the sensor, combines the vehicle conditions, the target steering angle and the steering assist force, controls the steering gear and the steering transmission mechanism to perform control actions, so as to realize the control of the vehicle steering.

[0012] As shown in the method shown in Figure 1 , the method comprises: Step 101, obtaining vehicle state parameters, the vehicle state parameters including the front wheel steering angle and the vehicle yaw rate.

[0013] The vehicle state parameters are obtained by the sensor, or the vehicle state parameters are stored in the vehicle locally, and the vehicle state parameters are obtained from the vehicle locally when needed.

[0014] Exemplarily, the vehicle state is detected by a sensor and a corresponding electrical signal is generated, the electrical signal is converted into a vehicle state parameter after processing; exemplarily, the vehicle state parameter stored locally by the vehicle can be managed by an electronic control unit (ECU) of the vehicle, when the device needs to call the front wheel steering angle and other parameters, the corresponding parameters are read from the specified storage address according to the preset communication protocol through the data communication link established with the ECU.

[0015] The vehicle state parameter includes the front wheel steering angle and the vehicle yaw rate, the front wheel steering angle is used to describe the steering angle of the front wheel of the vehicle, and the vehicle yaw rate is used to describe the speed of rotation of the vehicle around the vertical axis.

[0016] In step 102, the discretized vehicle state equation and the vehicle yaw rate expectation are determined based on the vehicle state parameter.

[0017] The discretized vehicle state equation is obtained through steps 201-205, and the steps 201-205 are as follows: In step 201, the dynamic differential equation in the vehicle motion process is constructed based on the vehicle state parameter.

[0018] Figure 2 is a schematic diagram of the vehicle motion model in the embodiment of the application. The schematic diagram presents the motion state of the vehicle in the driving process in a simplified two-dimensional plane form. In the embodiment of the application, the suspension effect of the vehicle is not considered, that is, the pitching motion, rolling motion and vertical motion of the vehicle body are ignored, the vehicle maintains a uniform speed in the driving process, the front wheel steering angle is taken as a direct input, and the tire side slip characteristic acts in a linear range, so only the lateral motion and yaw motion of the vehicle are considered.

[0019] The dynamic differential equation in the vehicle motion process is used to describe the vehicle motion, and the dynamic differential equation is as follows:

[0020] wherein m is the mass of the vehicle, is the lateral acceleration of the vehicle, I z is the moment of inertia of the vehicle, v x is the longitudinal speed of the vehicle, v y is the lateral speed of the vehicle, delta is the front wheel steering angle, b is the distance from the front axle to the center of mass of the vehicle, is the distance from the rear axle to the center of mass of the vehicle, and γ is the vehicle yaw rate, F yf and F yrThe lateral forces of the front and rear wheels, respectively.

[0021] Step 202, constructing a vehicle lateral force model based on the vehicle state parameters.

[0022] The vehicle lateral force model is a mathematical model used to describe the force conditions and lateral motion characteristics of the vehicle in the lateral direction. Based on the vehicle state parameters, the vehicle lateral force model is constructed. Figure 2 Through force analysis of the vehicle, the vehicle lateral force model is as follows:

[0023] wherein, C f is the side slip angle of the vehicle, C r is the rear wheel side slip angle, the longitudinal vehicle speed v x , the lateral vehicle speed v y , the front wheel steering angle δ.

[0024] Step 203, obtaining a linear two-degree-of-freedom dynamics model of the vehicle according to the dynamics differential equation and the vehicle lateral force model.

[0025] Since the dynamics differential equation and the vehicle lateral force model both have F yf and F yr , the linear two-degree-of-freedom dynamics model of the vehicle can be obtained by simultaneously solving the dynamics differential equation and the vehicle lateral force model, and the linear two-degree-of-freedom dynamics model is as follows: , wherein, since the front wheel steering angle δ and the vehicle center of mass side slip angle β are small in value, when simultaneously solving the dynamics differential equation and the vehicle lateral force model, let , , .

[0026] Step 204, converting the linear two-degree-of-freedom dynamics model into a vehicle state space equation.

[0027] The vehicle state space mathematical model is as follows: , wherein, , , , , , .

[0028] Step 205, discretizing the vehicle state space equation to obtain a discretized vehicle state space equation.

[0029] In this embodiment, the state vector of the vehicle state space equation is decomposed using the Euler method and substituted into the vehicle state space equation to obtain the discretized vehicle state equation. The decomposition formula is as follows:

[0030] Where T is the sampling time.

[0031] The discretized vehicle state equations are as follows:

[0032] in, , , , .

[0033] The expected yaw rate of the vehicle is obtained using the following formula: .

[0034] K is the vehicle stability factor. , is the road surface adhesion coefficient, g is the gravitational acceleration, and sgn(·) is the sign function.

[0035] The road surface adhesion coefficient is a preset value, or it can be obtained by segmenting and classifying the road image using deep learning algorithms, determining the road surface category, and then obtaining the road surface adhesion coefficient by looking up a table, such as by using a table of correspondence between road surface category and road surface adhesion coefficient to determine the road surface adhesion coefficient for that road surface category.

[0036] Step 103: Construct a sliding surface based on the discretized vehicle yaw rate and the expected vehicle yaw rate in the discretized vehicle state equation.

[0037] A sliding surface is a virtual switching hyperplane. The system state can be guided to this plane and slide along it, ultimately achieving the tracking or adjustment of the target state.

[0038] In this application example, the sliding surface s(k)=e(k)=γd(k)-γ(k), where γ(k) is the discretized vehicle yaw rate and γd(k) is the expected discretized vehicle yaw rate.

[0039] The discretized vehicle yaw rate expectation is obtained by discretizing the vehicle yaw rate expectation. The discrete vehicle yaw rate expectation is as follows:

[0040] Step 104: Based on the sliding surface, determine the front wheel steering angle control force output by the steering unit. The front wheel steering angle control force is used to change the size of the front wheel steering angle.

[0041] Step 104 includes: Steps 301-302.

[0042] Step 301: Determine the front wheel steering angle control law based on the sliding surface.

[0043] Since the sliding dynamics of the sliding surface at time K is s(k)=e(k)=γd(k)-γ(k), then the sliding dynamics at time K+1 is:

[0044] Combining the discretized vehicle state equations in step 205, we can obtain: (1) In this embodiment of the application, the improved Gao's reaching law is designed as follows: (2) Where T is the sampling time, α is an empirical value, preferably α=0.5, and q1 and q2 are adjustable parameters of the reaching law, both of which are greater than 0.

[0045] Combining formulas (1) and (2), we can obtain:

[0046] Rearranging the terms, we get:

[0047] That is, the front wheel steering angle control law : .

[0048] In this embodiment, by adopting and discretizing the Gao's reaching law, a discretized reaching law is configured for the discrete sliding surface, so that the system state accelerates when it is far away from the sliding surface and automatically decelerates when it is close to the sliding surface. This is beneficial for the system to converge quickly, improves the real-time performance of the vehicle's active front wheel steering control, effectively reduces the chattering caused by high-frequency switching, and maintains the system's strong robustness to disturbances, thereby improving the stability of the vehicle's active front wheel steering control.

[0049] In this embodiment, the vehicle's active front wheel steering is controlled by discrete sliding mode, which eliminates the need for additional continuous-discrete conversion in the vehicle steering system, reducing the computational burden of real-time control and making it suitable for embedded system deployment.

[0050] Step 302: Determine the front wheel steering angle control force output by the steering unit according to the front wheel steering angle control law.

[0051] The front wheel steering angle control law is a function used to determine the value of the front wheel steering angle control force. Therefore, after obtaining the front wheel steering angle control law, it is provided to the steering unit (steering control system). The steering unit determines the magnitude of the force required to change the wheel steering angle based on the front wheel steering angle control law, thereby determining the front wheel steering angle control force output by the steering unit. The wheel steering angle is changed by the front wheel steering angle control force.

[0052] The steering control system includes at least one of the following: a steering transmission mechanism and a steering gear.

[0053] This application obtains vehicle state parameters, determines discretized vehicle state equations and desired yaw rate based on these parameters, and constructs a discrete sliding surface according to the discretized yaw rate and desired yaw rate in the discretized vehicle state equations. Using this discrete sliding surface, the front wheel steering angle control force output by the steering unit is determined. Furthermore, by changing the front wheel steering angle based on this control force, smooth control of the front wheel steering can be achieved when approaching the sliding surface. This effectively reduces chattering caused by high-frequency switching while maintaining strong robustness to disturbances, improving the stability of the vehicle's active front wheel steering control. It also enables the vehicle's front wheel steering to converge quickly to the desired yaw rate, significantly reducing steering delay. This results in superior dynamic response and safety in scenarios such as emergency obstacle avoidance or low-adhesion surfaces. Moreover, the system accelerates towards the sliding surface from a distance and automatically decelerates upon approaching it, facilitating rapid system convergence and improving the real-time performance of the vehicle's active front wheel steering control.

[0054] In another embodiment of this application, the method includes steps 401-404.

[0055] Step 401: Obtain the adjustable parameters in the front wheel steering angle control law.

[0056] As can be seen from step 301, the adjustable parameters are q1 and q2 in the approach law, while the front wheel steering angle control law... Based on q1 and q2, the front wheel steering angle control law can be optimized by optimizing q1 and q2.

[0057] When obtaining adjustable parameters, they can be obtained from the front wheel steering angle control law, the improved Gao's approach law, or, if the adjustable parameters are stored locally, they can be called locally.

[0058] Step 402: Construct an objective function based on the vehicle yaw rate and the expected vehicle yaw rate; Step 402 includes: Step 4021 and Step 4022.

[0059] Step 4021: Determine the error based on the vehicle yaw rate and the expected value of the vehicle yaw rate, that is, determine the error e between the expected value and the actual value of the vehicle yaw rate. The error e is determined by the following formula:

[0060] Step 4022: Determine the objective function based on the error.

[0061] The formula for the objective function J is as follows: , where t is the time parameter.

[0062] Step 403: Optimize the adjustable parameters based on the particle swarm optimization algorithm and the objective function to obtain the first adjustable parameter.

[0063] like Figure 3 As shown in the embodiment of this application, based on the Matlab / Simulink scenario, and based on the particle swarm optimization algorithm and objective function, q1 and q2 in the front wheel steering angle control law are optimized.

[0064] In this embodiment, a particle swarm is first randomly generated, and q1 and q2 are assigned to the particles in the swarm sequentially. Then, the vehicle control system model is executed to obtain the objective function value, and the process is iterated repeatedly to optimize the objective function value. If the number of iterations meets the termination condition, the first adjustable parameter is output; if the number of iterations does not meet the termination condition, the particle swarm is updated, and the step of randomly generating the particle swarm is executed again. In this embodiment, the objective function is optimized by continuously adjusting the position and velocity of particles. The particle position update is primarily calculated based on its current position, its own historical best position, and the group's historical best position, while the velocity update comprehensively considers the influence of parameters such as inertia weight, individual learning factor, and social learning factor. During each iteration, the objective function values ​​for all particles are evaluated, and the optimal solutions for both individuals and the group are updated. Through this continuous iterative optimization mechanism, the adjustable parameters q1 and q2 gradually converge to their optimal values, thereby improving the control accuracy and stability of the vehicle steering control system and better meeting the steering requirements of the vehicle under different driving conditions.

[0065] Step 404: Update the adjustable parameters in the front wheel steering angle control law using the first adjustable parameter to obtain the first front wheel steering angle control law.

[0066] In this embodiment of the application, by optimizing the adjustable parameters, the front wheel steering angle control force output by the steering unit is determined by the first front wheel steering angle control law, and the size of the front wheel steering angle is changed based on the front wheel steering angle control force, so that the size of the front wheel steering angle can be controlled more accurately.

[0067] This application utilizes Matlab / Simulink to build an active front wheel steering control law for vehicles based on a discrete sliding mode control algorithm, and verifies the vehicle steering control method of this application in maintaining vehicle stability under double lane change conditions. Figures 4-7 This is a simulation diagram of the vehicle steering control method according to an embodiment of this application.

[0068] Figure 4 This is the front wheel steering angle simulation curve provided in the dual lane change operation embodiment of this application, such as... Figure 4 As shown, the controller (front wheel steering angle controller) can quickly adjust the vehicle steering angle and has a smooth response curve, ensuring the stability of the steering system.

[0069] Figure 5 The simulation curve of yaw rate under dual-track shifting conditions provided in the embodiments of this application is as follows: Figure 5 As shown, the yaw rate response curves are all close to their ideal values, meaning that the actual yaw rate of the vehicle under continuous steering conditions can quickly converge to its ideal value (the expected yaw rate of the vehicle) without any phase lag problem. This indicates that the vehicle steering control method based on discrete sliding mode in this application can meet the dynamic requirements of complex working conditions.

[0070] Figure 6 The simulation curves for dual-lane-change path tracking provided in the embodiments of this application are as follows: Figure 6 As shown, the vehicle's trajectory tracking performance is good, with only minor deviations occurring at lane changes and small-radius curves. The sliding mode control law has a rapid response to lateral displacement errors, ensuring the trajectory tracking performance.

[0071] Figure 7 This is a simulation curve of the vehicle's center of gravity sideslip angle under dual lane change conditions provided in the embodiments of this application, such as... Figure 7 As shown, the vehicle steering control method designed in this application has good robustness, can suppress lateral force disturbances, and makes the fluctuation of the center of gravity sideslip angle small and always within the safe range.

[0072] See Figure 8 This application provides a vehicle steering control device, which includes: The first acquisition module 501 is used to acquire vehicle status parameters, including the front wheel steering angle and the vehicle yaw rate. The second determining module 502 is used to determine the discretized vehicle state equation and the expected vehicle yaw rate based on the vehicle state parameters. The third construction module 503 is used to construct a sliding surface based on the discretized vehicle yaw rate and the expected vehicle yaw rate in the discretized vehicle state equation. The fourth determining module 504 is used to determine the front wheel steering angle control force output by the steering unit based on the sliding surface. The front wheel steering angle control force is used to change the size of the front wheel steering angle.

[0073] In one possible implementation, the second determining module 502 includes: The dynamic differential module is used to construct the dynamic differential equations of the vehicle motion process based on the vehicle state parameters; The lateral force module is used to construct a lateral force model of the vehicle based on vehicle state parameters; The first submodule is used to obtain the linear two-degree-of-freedom dynamic model of the vehicle based on the dynamic differential equation and the vehicle lateral force model. The conversion module is used to convert a linear two-degree-of-freedom dynamics model into vehicle state-space equations. The second submodule is used to discretize the vehicle state space equations to obtain discretized vehicle state equations.

[0074] In one possible implementation, the fourth determining module 504 includes: The third submodule is used to determine the front wheel steering angle control law based on the sliding surface; The fourth submodule is used to determine the front wheel steering angle control force output by the steering unit based on the front wheel steering angle control law.

[0075] In one possible implementation, the device further includes: Adjustable parameter acquisition module, used to acquire adjustable parameters in the front wheel steering angle control law; The objective function construction module is used to construct an objective function based on the vehicle yaw rate and the expected vehicle yaw rate. The fifth submodule is used to optimize the adjustable parameters based on the particle swarm optimization algorithm and the objective function to obtain the first adjustable parameter; The update module is used to update the adjustable parameters in the front wheel steering angle control law through the first adjustable parameters to obtain the first front wheel steering angle control law; The fourth submodule is specifically used to determine the front wheel steering angle control force output by the steering unit based on the first front wheel steering angle control law.

[0076] This device acquires vehicle state parameters and, based on these parameters, determines the discretized vehicle state equation and the desired yaw rate. Using the discretized yaw rate and its desired value from the discretized state equation, a discrete sliding surface is constructed. This discrete sliding surface is then used to determine the front wheel steering control force output by the steering unit. Furthermore, by changing the front wheel steering angle based on this control force, smooth control of the front wheel steering can be achieved as the vehicle approaches the sliding surface. This effectively reduces chattering caused by high-frequency switching while maintaining strong robustness to disturbances, improving the stability of the vehicle's active front wheel steering control. It also enables the front wheel steering to converge quickly to the desired yaw rate, significantly reducing steering delay. This results in superior dynamic response and safety in scenarios such as emergency obstacle avoidance or low-adhesion surfaces. Moreover, the device accelerates towards the sliding surface from a distance and automatically decelerates upon approaching it, facilitating rapid system convergence and improving the real-time performance of the active front wheel steering control.

[0077] It should be noted that the apparatus provided in the above embodiments is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the apparatus and method embodiments provided in the above embodiments belong to the same concept, and their specific implementation process can be found in the method embodiments, which will not be repeated here.

[0078] In an exemplary embodiment, a computer-readable storage medium is also provided, which stores at least one computer program that is loaded and executed by a processor of a computer device to enable the computer to implement any of the above-described vehicle steering control methods.

[0079] In one possible implementation, the aforementioned computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CD-ROM), magnetic tape, floppy disk, and optical data storage device, etc.

[0080] In an exemplary embodiment, a computer program product or computer program is also provided, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform any of the vehicle steering control methods described above.

[0081] It should be noted that all information (including but not limited to user device information, user personal information, etc.), data (including but not limited to data used for analysis, stored data, displayed data, etc.), and signals involved in this application are authorized by the user or fully authorized by all parties, and the collection, use, and processing of related data must comply with the relevant laws, regulations, and standards of the relevant countries and regions. For example, the environmental images of the vehicle's surroundings, road preprocessing and recognition results, road matching results, first duration, second duration, and control strategy involved in this application were all obtained with full authorization.

[0082] It should be understood that "multiple" as used in this article refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0083] It should be noted that the terms "first," "second," etc. (if applicable) in the specification and claims of this application 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 interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0084] The above description is merely an exemplary embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the principles of this application should be included within the protection scope of this application.

Claims

1. A vehicle steering control method, characterized in that, The method includes: Obtain vehicle status parameters, including front wheel steering angle and vehicle yaw rate; Based on the vehicle state parameters, the discretized vehicle state equation and the expected vehicle yaw rate are determined. Based on the discretized vehicle yaw rate and the expected vehicle yaw rate in the discretized vehicle state equation, a sliding mode surface is constructed; Based on the sliding surface, the front wheel steering angle control force output by the steering unit is determined, and the front wheel steering angle control force is used to change the size of the front wheel steering angle.

2. The method according to claim 1, characterized in that, The discretized vehicle state equations are obtained through the following steps: Based on the vehicle state parameters, a dynamic differential equation for the vehicle motion process is constructed. Based on the vehicle state parameters, a lateral force model of the vehicle is constructed; Based on the dynamic differential equation and the vehicle lateral force model, a linear two-degree-of-freedom dynamic model of the vehicle is obtained. The linear two-degree-of-freedom dynamics model is converted into a vehicle state-space equation; The vehicle state space equation is discretized to obtain the discretized vehicle state equation.

3. The method according to claim 1, characterized in that, The determination of the front wheel steering angle control force output by the steering unit based on the sliding surface includes: Based on the sliding surface, the front wheel steering angle control law is determined; The front wheel steering angle control force output by the steering unit is determined based on the front wheel steering angle control law.

4. The method according to claim 3, characterized in that, Before determining the front wheel steering angle control force output by the steering unit according to the front wheel steering angle control law, the method further includes: Obtain the adjustable parameters in the front wheel steering angle control law; Construct an objective function based on the vehicle yaw rate and the expected vehicle yaw rate; The adjustable parameters are optimized based on the particle swarm optimization algorithm and the objective function to obtain the first adjustable parameter; The first adjustable parameter is used to update the adjustable parameter in the front wheel steering angle control law to obtain the first front wheel steering angle control law. The step of determining the front wheel steering angle control force output by the steering unit according to the front wheel steering angle control law includes: determining the front wheel steering angle control force output by the steering unit according to the first front wheel steering angle control law.

5. A vehicle steering control device, characterized in that, The device includes: The first acquisition module is used to acquire vehicle status parameters, including the front wheel steering angle and the vehicle yaw rate. The second determining module is used to determine the discretized vehicle state equation and the expected vehicle yaw rate based on the vehicle state parameters. The third construction module is used to construct a sliding surface based on the discretized vehicle yaw rate and the expected vehicle yaw rate in the discretized vehicle state equation. The fourth determining module is used to determine the front wheel steering angle control force output by the steering unit based on the sliding surface, and the front wheel steering angle control force is used to change the size of the front wheel steering angle.

6. The apparatus according to claim 5, characterized in that, The second determining module includes: The dynamic differential module is used to construct the dynamic differential equations of the vehicle motion process based on the vehicle state parameters; The lateral force module is used to construct a lateral force model of the vehicle based on the vehicle state parameters; The first submodule is used to obtain the linear two-degree-of-freedom dynamic model of the vehicle based on the dynamic differential equation and the vehicle lateral force model. The conversion module is used to convert the linear two-degree-of-freedom dynamic model into vehicle state-space equations. The second submodule is used to discretize the vehicle state space equation to obtain the discretized vehicle state equation.

7. The apparatus according to claim 5, characterized in that, The fourth determining module includes: The third submodule is used to determine the front wheel steering angle control law based on the sliding surface; The fourth submodule is used to determine the front wheel steering angle control force output by the steering unit based on the front wheel steering angle control law.

8. The apparatus according to claim 7, characterized in that, The device further includes: Adjustable parameter acquisition module, used to acquire adjustable parameters in the front wheel steering angle control law; The objective function construction module is used to construct an objective function based on the vehicle yaw rate and the expected vehicle yaw rate. The fifth submodule is used to optimize the adjustable parameters based on the particle swarm optimization algorithm and the objective function to obtain the first adjustable parameter; The update module is used to update the adjustable parameters in the front wheel steering angle control law through the first adjustable parameters to obtain the first front wheel steering angle control law; The fourth submodule is specifically used to determine the front wheel steering angle control force output by the steering unit based on the first front wheel steering angle control law.

9. An electronic device, characterized in that, It includes a processor and a memory, the memory storing programs or instructions that can run on the processor, the programs or instructions being executed by the processor to implement the vehicle steering control method as described in any one of claims 1-4.

10. A non-transitory computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which is loaded and executed by a processor to implement the vehicle steering control method as described in any one of claims 1 to 4.

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