Vehicle transverse control method and device, medium, driving assistance system and vehicle

Abstract

The invention discloses a vehicle transverse control method and device, a medium, a driving assistance system and a vehicle, the vehicle transverse control method comprises the steps that a first steering wheel angle value and a second steering wheel angle value are obtained, the first steering wheel angle value is obtained through a first controller based on the modern control theory, and the second steering wheel angle value is obtained through a second controller based on the modern control theory; the second steering wheel angle value is obtained through a second controller based on the classical control theory; a steering wheel fusion corner value is obtained to control steering of the vehicle, and the steering wheel fusion corner value is obtained by fusing the first steering wheel corner value and the second steering wheel corner value. According to the method, the accuracy, the flexibility and the response speed of vehicle transverse control can be improved, the vehicle can be better kept in the lane center line in the driving process, transverse errors are reduced, therefore, complex scenes such as road inclination and S curves are effectively dealt with, and the safety and the stability of the vehicle in the complex driving environment are ensured.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a vehicle lateral control method, electronic equipment, non-volatile readable storage medium, driving assistance system and vehicle. Background Art

[0002] With the continuous development of autonomous driving technology, assisted driving functions have become an important part of modern vehicles. As one of the core functions of assisted driving, the performance of the control algorithm of lateral control directly affects the lateral control performance of the vehicle in various driving scenarios. At present, the existing lateral control methods mainly adopt feedforward control based on Ackerman steering and cascade PID (Proportion Integration Differentiation, proportional-integral-differential controller) feedback control.

[0003] However, these control methods still have obvious shortcomings in some complex scenarios. For example, in S-curves or curves with large curvature, the feedforward control based on the Ackerman model is not able to dynamically adapt to changes in the curvature of the curve, and cannot provide sufficient flexibility or precise steering control, resulting in the vehicle being unable to track the ideal trajectory during sharp turns or continuous turns, making it difficult for the vehicle to return to the center of the lane smoothly, resulting in excessive deviation or even throwing out of the lane. When a vehicle is driving on an inclined road, the gravity component will affect the lateral force distribution of the vehicle, especially the lateral control force acting on the steering wheel. In this case, the feedforward control based on Ackerman steering cannot effectively compensate for the lateral error caused by the road tilt, causing the vehicle to deviate from the center of the lane, and the cascade PID feedback control often shows a response lag in complex scenarios and cannot correct the deviation in time, thereby affecting the safety and stability of vehicle driving. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present invention is to propose a vehicle lateral control method, which can improve the accuracy, flexibility and response speed of vehicle lateral control, help the vehicle to better stay in the center of the lane during driving, reduce lateral errors, and effectively deal with complex scenes such as road inclination and S-curves, ensuring the safety and stability of the vehicle in complex driving environments.

[0005] A second objective of the present invention is to provide an electronic device.

[0006] A third object of the present invention is to provide a non-volatile readable storage medium.

[0007] A fourth objective of the present invention is to provide a driving assistance system.

[0008] A fifth object of the present invention is to provide a vehicle.

[0009] In order to achieve the above-mentioned purpose, the vehicle lateral control method of the first aspect of the embodiment of the present invention includes: obtaining a first steering wheel angle value and a second steering wheel angle value, wherein the first steering wheel angle value is obtained by a first controller based on modern control theory, and the second steering wheel angle value is obtained by a second controller based on classical control theory; obtaining a steering wheel fusion angle value to control vehicle steering, wherein the steering wheel fusion angle value is obtained by fusing the first steering wheel angle value and the second steering wheel angle value.

[0010] According to the vehicle lateral control method of the embodiment of the present invention, a first controller based on modern control theory and a second controller based on classical control theory are used to obtain a first steering wheel angle value and a second steering wheel angle value respectively, and the two are fused to obtain a steering wheel fusion angle value, thereby achieving more accurate vehicle steering control. Among them, the first controller based on modern control theory can flexibly adjust the trade-off between the response speed and control accuracy of the system, so it has the ability to respond quickly to complex scenes and ensure timely adjustment of the vehicle's steering angle. The classical controller can correct the lateral deviation of the vehicle by accumulating errors, so that the vehicle gradually returns to the desired trajectory and ensures that the vehicle is finally near the center of the lane. By combining the two control strategies, the method not only improves the accuracy and flexibility of lateral control, but also speeds up the response speed, effectively reduces the lateral error of the vehicle deviating from the center of the lane, thereby effectively coping with complex scenes such as road inclination and S-curves, and ensuring the safety and stability of the vehicle in complex driving environments.

[0011] In some embodiments, the first controller includes a feedback controller based on a vehicle kinematics and dynamics model; the first steering wheel angle value is obtained by the feedback controller using parameters of the vehicle kinematics and dynamics model as input.

[0012] In some embodiments, the feedback controller includes a linear quadratic regulator; the state quantity of the linear quadratic regulator is a matrix composed of multiple vehicle lateral parameters; the objective function of the linear quadratic regulator is expressed as the integral of the state quantity, the first weight matrix, the first steering wheel angle value and the second weight matrix with respect to time; the first weight matrix is ​​the weight matrix of the state quantity, and the second weight matrix is ​​the weight matrix of the first steering wheel angle value.

[0013] In some embodiments, the vehicle lateral parameters include lateral error, lateral error rate, yaw error and yaw error rate.

[0014] In some embodiments, the parameters of the vehicle kinematics and dynamics model include at least vehicle body parameters, an angle between the vehicle and the horizontal axis in the lane map coordinate system, and a lateral error of the vehicle body.

[0015] In some embodiments, the vehicle body parameters include at least moment of inertia, cornering stiffness, wheelbase and vehicle mass.

[0016] In some embodiments, the lateral error of the vehicle body is the difference between the center of the rear axle of the vehicle and the lane reference line.

[0017] In some embodiments, the linear quadratic regulator uses the vehicle parameters, the angle between the vehicle and the horizontal axis of the lane map coordinate system, and the lateral error of the vehicle body as input to obtain a state feedback control coefficient; the first steering wheel angle value is obtained based on the state feedback control coefficient and the state quantity.

[0018] In some embodiments, the state feedback control coefficient is obtained by calculating the linear quadratic regulator through the algebraic Riccati equation.

[0019] In some embodiments, the second controller comprises an integral controller, which uses the lateral error of the vehicle body as input to obtain the second steering wheel angle value.

[0020] In some embodiments, the lateral error of the vehicle body is the difference between the center of the rear axle of the vehicle and the lane reference line.

[0021] In some embodiments, the fused steering wheel angle value is the sum of the first steering wheel angle value and the second steering wheel angle value.

[0022] In order to achieve the above-mentioned purpose, the electronic device of the second embodiment of the present invention includes: at least one processor; a memory communicatively connected to the at least one processor; the memory stores a computer program executable by the at least one processor, and when the at least one processor executes the computer program, it implements the vehicle lateral control method described in the above embodiment.

[0023] According to the electronic device of the embodiment of the present invention, at least one processor executes a computer program for implementing the vehicle lateral control method described in the above embodiment, and obtains the first steering wheel angle value and the second steering wheel angle value respectively by using a first controller based on modern control theory and a second controller based on classical control theory, and fuses the two to obtain the steering wheel fusion angle value, thereby realizing more accurate vehicle steering control. Among them, the first controller based on modern control theory can flexibly adjust the trade-off between the response speed and control accuracy of the system, so it has the ability to respond quickly to complex scenes and ensure timely adjustment of the steering angle of the vehicle. The classical controller can correct the lateral deviation of the vehicle by accumulating errors, so that the vehicle gradually returns to the desired trajectory and ensures that the vehicle is finally near the center line of the road. By combining the two control strategies, the method not only improves the accuracy and flexibility of lateral control, but also ensures the response speed, effectively reduces the lateral error of the vehicle deviating from the center of the lane, thereby effectively coping with complex scenes such as road inclination and S-curves, and ensuring the safety and stability of the vehicle in complex driving environments.

[0024] In order to achieve the above-mentioned purpose, the non-volatile readable storage medium of the third aspect of the present invention has a computer program stored thereon, and when the computer program is executed, the vehicle lateral control method described in the above embodiment is implemented.

[0025] According to the non-volatile readable storage medium of the embodiment of the present invention, by adopting the vehicle lateral control method described in the above embodiment, the accuracy, flexibility and response speed of the vehicle lateral control can be improved, which helps the vehicle to better stay near the center of the lane during driving and reduce lateral errors, thereby effectively coping with complex scenarios such as road inclinations and S-curves, ensuring the safety and stability of the vehicle in complex driving environments.

[0026] In order to achieve the above-mentioned purpose, the driving assistance system of the fourth aspect of the present invention includes the electronic device described in the above embodiment.

[0027] According to the driving assistance system of the embodiment of the present invention, by adopting the electronic device described in the above embodiment, the system can execute the vehicle lateral control method described in the above embodiment, thereby improving the lateral control accuracy, flexibility and response speed of the vehicle. At least one processor in the electronic device executes a computer program stored in the memory, and uses a first controller based on modern control theory and a second controller based on classical control theory to obtain a first steering wheel angle value and a second steering wheel angle value respectively, and fuses these two values ​​to generate a steering wheel fusion angle value. This fusion not only ensures the system's rapid response capability in complex driving scenarios and adjusts the steering angle of the vehicle in a timely manner, but also performs integral control through the classical controller, and can continuously accumulate deviations to correct them when there is an offset, thereby gradually reducing the offset, so that the vehicle is better kept near the center of the lane during driving. Therefore, the driving assistance system can effectively cope with complex scenarios such as road inclinations and S-shaped curves, thereby ensuring the safety and stability of the vehicle in a variety of driving environments.

[0028] In order to achieve the above-mentioned purpose, the vehicle of the fifth embodiment of the present invention includes the electronic device described in the above embodiment or includes the driving assistance system described in the above embodiment.

[0029] The vehicle according to the embodiment of the present invention can improve the accuracy, flexibility and response speed of the vehicle's lateral control by adopting the electronic equipment or driving assistance system described in the above embodiment, which helps the vehicle to better maintain near the center of the lane during driving and reduce lateral errors, thereby effectively coping with complex scenarios such as road inclinations and S-curves, thereby ensuring the safety and stability of the vehicle in complex driving environments.

[0030] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 is a flow chart of a vehicle lateral control method according to an embodiment of the present invention; Figure 2 is a schematic diagram of a vehicle kinematics model according to an embodiment of the present invention; Figure 3 is a schematic diagram of a vehicle dynamics model according to an embodiment of the present invention; Figure 4 is a schematic diagram of a lateral error of a vehicle body according to an embodiment of the present invention; Figure 5is a logic block diagram of a vehicle lateral control method according to an embodiment of the present invention; Figure 6 is a block diagram of an electronic device according to an embodiment of the present invention; Figure 7 is a block diagram of a driving assistance system according to an embodiment of the present invention; Figure 8 is a block diagram of a vehicle according to one embodiment of the present invention; Fig. 9 is a block diagram of a vehicle according to yet another embodiment of the present invention.

[0032] Reference numerals: Vehicle 100; Driver assistance system 1; Electronic device 10; Processor 11; Memory 12. DETAILED DESCRIPTION

[0033] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0034] Reference below Figure 1-Figure 5 A vehicle lateral control method according to an embodiment of the present invention is described.

[0035] Figure 1 is a flow chart of a vehicle lateral control method according to an embodiment of the present invention. Figure 1 As shown, the vehicle lateral control method according to the embodiment of the present invention includes steps S1-S2.

[0036] S1, obtaining a first steering wheel angle value and a second steering wheel angle value, wherein the first steering wheel angle value is obtained by a first controller based on modern control theory, and the second steering wheel angle value is obtained by a second controller based on classical control theory.

[0037] In some embodiments, the steering wheel angle value is the physical angle of the steering wheel during the vehicle's steering operation, usually expressed in degrees, reflecting the deflection angle of the steering wheel relative to the neutral position (steering wheel position when driving straight). The change in the steering wheel angle can directly affect the steering angle of the wheel, determine the direction and amplitude of the wheel's rotation, and thus determine the steering trajectory of the vehicle.

[0038] In some embodiments, the steering wheel angle value is the core parameter for controlling the vehicle's driving direction and determines the vehicle's lateral motion state. Under complex road conditions, precise control of the steering wheel angle value can ensure that the vehicle remains in the center of the lane or drives along the desired trajectory to maintain the safety and stability of vehicle driving.

[0039] In some embodiments, the first controller based on modern control theory can be a controller based on a state space model, such as a model feedback controller. Compared with classical control theory, modern control theory pays more attention to the state feedback of the system, that is, it not only relies on the current output signal, but also combines all observable variables of the system state. This approach enables the system to respond faster and more accurately in a complex dynamic environment.

[0040] Among them, the model feedback controller is an important application of modern control theory. It estimates the current state of the vehicle in real time, combines the vehicle dynamics model, predicts the future state, and optimizes the next control input (i.e., the steering wheel angle value). This control strategy fully considers the dynamic characteristics of the vehicle, can predict future driving scenarios, and adjust the vehicle's steering in advance. For example, when making a sharp turn, the model feedback controller can quickly adjust the vehicle's steering behavior according to the vehicle speed and turning curvature to ensure that the vehicle drives smoothly and safely.

[0041] In some embodiments, the second controller based on classical control theory can provide the ability to correct accumulated errors. Among them, classical control theory is represented by PID control (proportional-integral-differential control), in which the integral term can compensate for the long-term accumulated error between the vehicle and the target path, ensuring that the vehicle always stays close to the center of the lane during long-term driving. Especially in S-curves or when the road is tilted left or right, classical control theory can gradually correct the deviation through a feedback mechanism to maintain a stable driving trajectory.

[0042] S2, obtaining a steering wheel fusion angle value to control vehicle steering, wherein the steering wheel fusion angle value is obtained by fusing the first steering wheel angle value and the second steering wheel angle value.

[0043] In some embodiments, the method for fusing the first steering wheel angle value and the second steering wheel angle value may be direct addition, weighted average, adaptive fusion or other methods. By fusing the two angle values ​​based on modern control theory and classical control theory, the system can have the advantages of both control strategies, which can not only quickly respond to instantaneous changes in dynamic scenes, but also correct accumulated errors to ensure the long-term stability of the system. The fused steering wheel angle value can better reflect the actual driving state of the vehicle, thereby improving the accuracy of steering. Especially in the face of complex road environments (such as S-curves, roads tilted left and right, etc.), the vehicle can better drive along the desired path and reduce errors that deviate from the center of the road.

[0044] According to the vehicle lateral control method of the embodiment of the present invention, a first controller based on modern control theory and a second controller based on classical control theory are used to obtain a first steering wheel angle value and a second steering wheel angle value respectively, and the two are fused to obtain a steering wheel fusion angle value, thereby achieving more accurate vehicle steering control. Among them, the first controller based on modern control theory can flexibly adjust the trade-off between the response speed and control accuracy of the system, so it has the ability to respond quickly to complex scenes and ensure timely adjustment of the vehicle's steering angle. The classical controller can correct the lateral deviation of the vehicle by accumulating errors, so that the vehicle gradually returns to the desired trajectory and ensures that the vehicle is finally near the center of the lane. By combining the two control strategies, the method not only improves the accuracy and flexibility of lateral control, but also speeds up the response speed, effectively reduces the lateral error of the vehicle deviating from the center of the lane, thereby effectively coping with complex scenes such as road inclination and S-curves, and ensuring the safety and stability of the vehicle in complex driving environments.

[0045] In some embodiments, the first controller includes a feedback controller based on a vehicle kinematic and dynamic model. Figure 2 As shown in the figure, the vehicle kinematic model describes the geometric relationship of vehicle motion and reflects the relationship between the steering angle and the turning radius. The specific formula is as follows: ; in, is the front wheel steering angle, L is the axle wheelbase, and R is the turning radius. This formula is based on the Ackerman steering geometry relationship, indicating that the steering angle ( ) is inversely proportional to the turning radius (R) of its driving path, that is, when the turning radius of the vehicle is smaller, a larger steering angle is required to keep the vehicle turning. The wheelbase (L), as an inherent property of the vehicle, affects the proportion of this relationship.

[0046] In some embodiments, Figure 3 As shown in Figure 1, the vehicle dynamics model takes into account the lateral force generated by the vehicle during the turning process and the dynamic behavior of the vehicle. This model is used to describe the behavior of the vehicle under different accelerations and external forces, especially the impact of lateral force on vehicle stability during turning. The specific formula is as follows: ; ; ; in, is the acceleration of the vehicle in the y direction (lateral direction). When turning, the vehicle will be subject to a lateral acceleration, which will affect the stability and grip of the vehicle; m is the mass of the vehicle; is the lateral force of the front wheel, which is generated by the sideslip of the front wheel and the friction of the ground; is the lateral force of the rear wheel, which is generated by the sideslip of the rear wheel and the friction of the ground; The cornering stiffness of the front wheel indicates the ability of the front wheel to resist sideslip when turning at a certain angle. The greater the stiffness, the greater the lateral force generated by the tire. is the cornering stiffness of the rear wheel, which indicates the ability of the rear wheel to resist sideslip when generating a steering angle; is the steering angle. Figure 3 In It is expressed as the angle between the vehicle and the horizontal axis of the lane map coordinate system.

[0047] In some embodiments, the first steering wheel angle value is obtained by a feedback controller using the parameters of the vehicle kinematic and dynamic models as input. Specifically, a typical type of feedback controller is a state feedback controller, also known as a state space controller, which is based on comprehensive monitoring of the vehicle state (such as speed, acceleration, steering angle, etc.). By converting the vehicle's kinematic and dynamic models into state space equations, the lateral movement of the vehicle can be better analyzed and controlled in the form of a linear system. Among them, the state space equation is a mathematical model that describes a dynamic system, which describes the change of the system state over time in matrix form. It can simplify complex differential equations into matrix operations, making it easier to apply in control algorithms. The formula of the state space equation is as follows: ; in, is the state vector, which indicates the motion state of the vehicle; A is the state matrix, which is derived from the physical parameters of the vehicle (such as wheelbase, mass, cornering stiffness, etc.); B is the input matrix, which reflects the influence of control input (such as steering angle) on the system state; is the control input, which represents the control input applied to the system, such as the first steering wheel angle value.

[0048] In some embodiments, the feedback controller includes a linear quadratic regulator (LQR), which aims to obtain the best control input by minimizing the quadratic objective function, thereby minimizing the trajectory error of the vehicle, while minimizing energy consumption and steering wheel over-adjustment, and ensuring driving stability and safety.

[0049] In some embodiments, the state quantity of the linear quadratic regulator is a matrix composed of multiple vehicle lateral parameters, wherein the vehicle lateral parameters include lateral error, lateral error rate, yaw error and yaw error rate. These parameters are key quantities in vehicle lateral control, used to describe the lateral deviation of the vehicle relative to the road and the deviation of the driving direction, and directly affect the accuracy and stability of the vehicle lateral control.

[0050] Among them, the lateral error can refer to the deviation of the vehicle from the center of the lane. It reflects the lateral distance between the current position of the vehicle and the desired path, and is a key parameter for controlling the vehicle to stay in the center of the lane or on the target path. The lateral error rate can be the rate of change of the lateral error over time, describing the speed of change of the lateral position of the vehicle relative to the predetermined trajectory. When the lateral error continues to increase or decrease, the lateral error rate can reflect the dynamic behavior of the vehicle deviating from the trajectory. For example, when the vehicle passes through a curve, if the lateral error rate is larger, it means that the vehicle is rapidly deviating from the predetermined trajectory. The yaw error can be the heading angle deviation between the current driving direction of the vehicle and the predetermined trajectory, that is, the difference between the actual heading angle of the vehicle and the expected heading angle. The yaw error rate can refer to the rate of change of the yaw error over time, reflecting the speed of change of the vehicle's yaw state. If the yaw error rate of the vehicle is high, it means that there is a large gap between the steering of the vehicle and the predetermined trajectory, and it may need to be adjusted immediately. If the yaw error rate is low or close to zero, it means that the heading angle of the vehicle is gradually approaching the expected heading angle.

[0051] In some embodiments, multiple vehicle lateral parameters (lateral error, lateral error rate, yaw error, and yaw error rate) are combined into a state matrix and input into the linear quadratic regulator. These parameters not only describe the current driving state of the vehicle, but also provide complete feedback information for the linear quadratic regulator to optimize the control input (the first steering wheel angle value).

[0052] In some embodiments, the objective function of the linear quadratic regulator is expressed as the integral of the state quantity, the first weight matrix, the first steering wheel angle value, and the second weight matrix over time, wherein the first weight matrix is ​​the weight matrix of the state quantity, and the second weight matrix is ​​the weight matrix of the first steering wheel angle value. The objective function expression is as follows: ; Among them, J is the objective function to be minimized; x is the state quantity; T represents transposition; Q is the weight matrix of the state quantity x, that is, the first weight matrix; is the control variable, i.e., the first steering wheel angle value; R is the weight matrix of the first steering wheel angle value, i.e., the second weight matrix.

[0053] In some embodiments, the first weight matrix is ​​used to measure the importance of each vehicle lateral parameter in the overall control cost. By adjusting the first weight matrix, weights can be assigned to different vehicle lateral parameters to prioritize certain errors or dynamic characteristics. For example, if the lateral error is more important than the yaw error, a larger weight can be given to the lateral error to enhance its influence in the control decision.

[0054] In some embodiments, the second weight matrix is ​​used to limit the change range of the first steering wheel angle value to avoid excessive changes in the control input. This helps to reduce unnecessary large-scale steering operations during vehicle adjustment, thereby maintaining driving stability and comfort.

[0055] In some embodiments, the parameters of the vehicle kinematics and dynamics model include at least vehicle body parameters, the angle between the vehicle and the horizontal axis in the lane map coordinate system, and the lateral error of the vehicle body. These parameters are used to provide more accurate input for the linear quadratic regulator (LQR), helping the system to better adjust the steering wheel angle in the lateral control of the vehicle.

[0056] In some embodiments, the body parameters include at least moment of inertia, cornering stiffness, wheelbase and vehicle mass. Among them, moment of inertia is a physical quantity that measures the magnitude of inertia of an object when it rotates around a specific axis. In vehicle lateral control, moment of inertia is mainly used to describe the rotation characteristics of the vehicle around its vertical axis, especially in dynamic scenarios such as turning and sideslipping. The larger the moment of inertia, the more difficult it is for the vehicle to change direction when turning. Therefore, in the linear quadratic regulator, the moment of inertia is used as an input parameter to help adjust the response speed of the steering wheel. For example, the larger the moment of inertia, the greater the inertia of the vehicle when turning, that is, the vehicle reacts slower to steering. On the contrary, the smaller the moment of inertia, the faster the vehicle responds to steering commands. In vehicle lateral control, the moment of inertia affects the stability and steering rate of the vehicle when turning.

[0057] In some embodiments, the cornering stiffness can be a description of the ability of the wheel to generate a steering angle under the action of a lateral force, reflecting the grip and response performance of the tire. Cornering stiffness is a key parameter that affects the lateral stability of the vehicle when it is in a curve or sharp turn. A higher cornering stiffness means that the wheel can maintain a stronger grip when a lateral force is applied, reducing the risk of the vehicle skidding. For example, when a vehicle enters a curve, the cornering stiffness of the wheel determines the steering sensitivity and stability of the vehicle. If the cornering stiffness is low, the vehicle is prone to lose grip when turning sharply, resulting in skidding or tail swinging. The linear quadratic regulator optimizes the steering wheel angle adjustment process through the cornering stiffness information, balancing the vehicle's steering requirements and the lateral grip of the wheels when turning, and ensuring the stability of the vehicle in the curve.

[0058] In some embodiments, the lateral error of the vehicle body is the difference between the center of the rear axle of the vehicle and the lane reference line. Figure 4 As shown, Figure 4 The thin black solid line in the figure is the center of the rear axle of the vehicle, the black dotted line is the lane reference line, and the thick black solid line is the difference between the two, that is, the lateral error of the vehicle body.

[0059] The rear axle of the vehicle is one of the main support points in the vehicle's forward direction, so it has a greater impact on the steering and control of the vehicle during driving. The lateral position of the rear axle center can help determine the degree of deviation between the vehicle and the lane reference line. Figure 4 As shown, the lane reference line can be simply considered as Figure 4 The solid line in the middle is the center line of the lane, which is used for relative positioning of the vehicle to the lane during lateral control. However, the lane reference line is obtained based on the lane information and vehicle information of the previous and next frames, so the lane reference line contains richer information than the lane center line.

[0060] In some embodiments, in the lateral control system of the vehicle, lateral error is a key feedback quantity. The system measures and calculates the lateral error, combines other relevant information (such as lateral error rate, yaw angle, etc.), and controls the angle of the steering wheel to correct the vehicle's driving path to ensure that the vehicle travels along the predetermined lane. For example, if the center of the vehicle's rear axle deviates from the lane reference line, the system can adjust the vehicle's steering according to the size and rate of change of the lateral error to guide the vehicle back to the center of the lane. The larger the lateral error, the more significant the system needs to adjust.

[0061] In some embodiments, the linear quadratic regulator uses the vehicle parameters, the angle between the vehicle and the horizontal axis of the lane map coordinate system, and the lateral error of the vehicle as input to obtain the state feedback control coefficient. Therefore, the design purpose of the linear quadratic regulator is to enable the vehicle to maintain the lane reference line through the appropriate first steering wheel angle value by solving the state feedback control coefficient (optimal control gain matrix).

[0062] In some embodiments, the state feedback control coefficient is calculated by the linear quadratic regulator through the algebraic Riccati equation. Among them, the algebraic Riccati equation is a matrix equation used to determine the control gain matrix in the optimal control law. In the linear quadratic regulator, the goal is to minimize a weighted quadratic cost function, which can be the weighted square sum of the state quantity and the control input. The algebraic Riccati equation is used to solve the optimal state feedback control coefficient in this problem. The standard form of the algebraic Riccati equation is as follows: ; Among them, A is the state matrix of the system; B is the input matrix of the system; P is the matrix to be solved (the solution of the algebraic Riccati equation); Q and R are the first weight matrix and the second weight matrix respectively. The algebraic Riccati equation cannot be directly obtained by a simple algebraic solution, but is solved by a numerical method. Common numerical methods include: iterative method and matrix decomposition method. The iterative method can continuously adjust and update the value of the matrix P until the equation convergence condition is met. The matrix decomposition method can be used, such as Cholesky decomposition or QR decomposition, to solve large-scale linear equations. This allows the algebraic Riccati equation to be implemented by computer in actual control systems, and the state feedback control coefficient can be quickly obtained for real-time adjustment of the first steering wheel angle value.

[0063] In some embodiments, the first steering wheel angle value is obtained according to the state feedback control coefficient and the state quantity. The specific formula is as follows: ; in, is the first steering wheel angle value; K is the state feedback control coefficient; x is the state quantity.

[0064] In some embodiments, the second controller includes an integral controller, wherein the integral controller is a part of a PID controller (proportional-integral-derivative controller) and reduces the steady-state error of the system by integrating the lateral error. In the lateral control of the vehicle, the integral controller can effectively eliminate the persistent lateral error, which may gradually accumulate in long-term driving and cause the vehicle to gradually deviate from the lane.

[0065] In some embodiments, the integral controller uses the lateral error of the vehicle body as input to obtain the second steering wheel angle value. The specific formula is as follows: ; in, is the second steering wheel angle; e is the lateral error of the vehicle body; ki is the adjustable gain, or the coefficient for adjusting the sensitivity of the integral controller. The ki value of different vehicles will be different. The ki value range can be between 0.001-0.1. The specific value depends on the dynamic characteristics, response speed and control requirements of the vehicle. A small gain may lead to a slow response, while an excessive gain may cause system oscillation or instability.

[0066] In some embodiments, the lateral error of the vehicle body is the difference between the center of the rear axle of the vehicle and the lane reference line. The rear axle of the vehicle is the key to the driving stability of the vehicle. In particular, when the vehicle is maneuvered and turned, the position of the rear axle has a more direct impact on lane deviation than the front axle. Therefore, using the lateral error of the rear axle center can more accurately reflect the actual deviation of the vehicle.

[0067] In some embodiments, the current position of the vehicle is obtained in real time by using sensors such as GPS (Global Positioning System), LiDAR, IMU (Inertial measurement unit), vision sensor, etc. In particular, the position of the rear axle center can be calculated by the vehicle geometry model. Lane reference lines can be detected in real time by on-board sensors or pre-defined by map data.

[0068] In some embodiments, the fusion steering wheel angle value is the sum of the first steering wheel angle value and the second steering wheel angle value. The specific calculation formula is as follows: ; Among them, u is the steering wheel fusion angle value; is the first steering wheel angle value; is the second steering wheel angle value.

[0069] In general, the steering wheel fusion angle value is the sum of the first steering wheel angle value and the second steering wheel angle value, which represents the final steering wheel rotation angle and is used to control the lateral movement of the vehicle. The purpose of this fusion control strategy is to combine two different control signals to obtain more accurate and stable steering wheel control. Among them, the first steering wheel angle value is mainly based on real-time vehicle dynamics and control algorithms to make a large range of corrections to the vehicle. For example, a linear quadratic regulator responds quickly according to the current state of the vehicle. The second steering wheel angle value accumulates and corrects the lateral error through an integral controller, which is mainly used to eliminate long-term steady-state errors and prevent the vehicle from continuously deviating from the lane.

[0070] Figure 5 is a logic block diagram of a vehicle lateral control method according to an embodiment of the present invention, such as Figure 5 As shown in the figure, the body parameters, the angle between the vehicle and the horizontal axis of the lane map coordinate system, and the lateral error of the body are input into the linear quadratic regulator. The linear quadratic regulator can obtain the state feedback control coefficient through the algebraic Riccati equation, and the first steering wheel angle value is obtained according to the state feedback control coefficient and the state quantity. The lateral error of the body is input into the integral controller to obtain the second steering wheel angle value, and the first steering wheel angle value and the second steering wheel angle value are summed to obtain the steering wheel fusion angle value. This control method can improve the accuracy, flexibility and response speed of the vehicle's lateral control, help the vehicle better stay in the center of the lane during driving, reduce the lateral error, and effectively deal with complex scenes such as road inclination and S-curves, ensuring the safety and stability of the vehicle in complex driving environments.

[0071] Reference below Figure 6 An electronic device according to an embodiment of the present invention is described.

[0072] Figure 6 is a block diagram of an electronic device according to an embodiment of the present invention, such as Figure 6 As shown, the electronic device 10 includes: a memory 12 and at least one processor 11.

[0073] In some embodiments, at least one processor 11 may be one processor 11, or may be two processors 11, three processors 11, five processors 11, or multiple processors 11. The processor 11 may be a single-core or multi-core processor 11, responsible for executing the vehicle lateral control algorithm in the memory 12, and dynamically calculating the vehicle control command. The processor 11 may be a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), etc. in the electronic device 10. It depends on the design and purpose of the electronic device 10.

[0074] In some embodiments, the memory 12 is used to store computer programs and related data, such as vehicle status information, road data, lane maps, etc. The memory 12 may include RAM (Random Access Memory), ROM (Read-Only Memory), flash memory or SSD (Solid State Drives), etc., for fast reading and writing data. The memory 12 can also store vehicle states at different stages (such as lateral error, vehicle speed, vehicle body posture, etc.) and previous control outputs to assist subsequent control calculations.

[0075] In some embodiments, the memory 12 is communicatively connected to at least one processor 11, and the memory 12 stores a computer program that can be executed by at least one processor 11. When the at least one processor 11 executes the computer program, the vehicle lateral control method described in the above embodiment is implemented.

[0076] According to the electronic device 10 of the embodiment of the present invention, at least one processor 11 executes a computer program for implementing the vehicle lateral control method described in the above embodiment, and obtains the first steering wheel angle value and the second steering wheel angle value respectively by using a first controller based on modern control theory and a second controller based on classical control theory, and fuses the two to obtain the steering wheel fusion angle value, thereby achieving more accurate vehicle steering control. Among them, the first controller based on modern control theory can flexibly adjust the trade-off between the response speed and control accuracy of the system, so it has the ability to respond quickly to complex scenes and ensure timely adjustment of the steering angle of the vehicle. The classical controller can correct the lateral deviation of the vehicle by accumulating errors, so that the vehicle gradually returns to the desired trajectory and ensures that the vehicle is finally near the center line of the road. By combining the two control strategies, the method not only improves the accuracy and flexibility of lateral control, but also ensures the response speed, effectively reduces the lateral error of the vehicle deviating from the center of the lane, thereby effectively coping with complex scenes such as road inclination and S-curves, and ensuring the safety and stability of the vehicle in complex driving environments.

[0077] The embodiment of the present invention further provides a non-volatile readable storage medium on which a computer program is stored, and when the computer program is executed, the vehicle lateral control method described in the above embodiment is implemented. The specific implementation process of the vehicle lateral control method can refer to the description of the above embodiment.

[0078] In some embodiments, the non-volatile readable storage medium may include, but is not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical or magnetic storage media, which are not listed here one by one.

[0079] According to the non-volatile readable storage medium of the embodiment of the present invention, by adopting the vehicle lateral control method described in the above embodiment, the accuracy, flexibility and response speed of the vehicle lateral control can be improved, which helps the vehicle to better stay near the center of the lane during driving and reduce lateral errors, thereby effectively coping with complex scenarios such as road inclinations and S-curves, ensuring the safety and stability of the vehicle in complex driving environments.

[0080] Reference below Figure 7 A driving assistance system according to an embodiment of the present invention is described.

[0081] Figure 7 is a block diagram of a driving assistance system according to an embodiment of the present invention. Figure 7 As shown, the driving assistance system 1 includes the electronic device 10 described in the above embodiment.

[0082] In some embodiments, the driving assistance system 1 is based on an electronic device 10, which implements a vehicle lateral control method (such as lane keeping, steering wheel control, etc.). The system uses the integrated electronic device 10 and computer program, on-board sensors and control algorithms to achieve the automatic driving assistance function of the vehicle under complex traffic conditions. This is not only through the lateral control of the vehicle, but also involves the comprehensive coordination of functions including lane keeping, adaptive cruise control, obstacle detection, etc., to improve the safety, comfort and intelligence level of driving.

[0083] According to the driving assistance system 1 of the embodiment of the present invention, by adopting the electronic device 10 described in the above embodiment, the system can execute the vehicle lateral control method described in the above embodiment, thereby improving the lateral control accuracy, flexibility and response speed of the vehicle. At least one processor 11 in the electronic device 10 obtains the first steering wheel angle value and the second steering wheel angle value respectively by executing the computer program stored in the memory, using the first controller based on modern control theory and the second controller based on classical control theory, and fuses the two values ​​to generate the steering wheel fusion angle value. This fusion not only ensures the rapid response capability of the system in complex driving scenes and adjusts the steering angle of the vehicle in time, but also performs integral control through the classical controller, and can continuously accumulate deviations to correct them when there is an offset, thereby gradually reducing the offset, so that the vehicle is better kept near the center of the lane during driving. Therefore, the driving assistance system can effectively cope with complex scenes such as road inclination and S-shaped curves, thereby ensuring the safety and stability of the vehicle in a variety of driving environments.

[0084] Reference below Figure 8-Figure 9 A vehicle according to an embodiment of the present invention is described.

[0085] Figure 8 is a block diagram of a vehicle according to an embodiment of the present invention, such as Figure 8 As shown, the vehicle 100 includes the electronic device 10 described in the above embodiment. The electronic device 10 can implement the vehicle lateral control method described in the above embodiment by executing the computer program, improve the accuracy, flexibility and response speed of the vehicle lateral control, and help the vehicle better stay near the center of the lane during driving.

[0086] Fig. 9 is a block diagram of a vehicle according to yet another embodiment of the present invention, Fig. 9 As shown, the vehicle 100 includes the driving assistance system 1 described in the above embodiment. The driving assistance system 1 can provide a series of auxiliary functions, such as lane keeping, adaptive cruise control, automatic emergency braking, blind spot detection, etc., which greatly improves driving safety and comfort.

[0087] In some embodiments, the vehicle 100 may be a fuel vehicle, an electric vehicle, a hybrid vehicle, etc.

[0088] According to the vehicle 100 of the embodiment of the present invention, by adopting the electronic device 10 or the driving assistance system 1 described in the above embodiment, the accuracy, flexibility and response speed of the vehicle's lateral control can be improved, which helps the vehicle 100 to better stay near the center of the lane during driving and reduce lateral errors, thereby effectively coping with complex scenarios such as road inclinations and S-curves, thereby ensuring the safety and stability of the vehicle 100 in complex driving environments.

[0089] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0090] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A vehicle lateral control method, characterized in that: include: Obtaining a first steering wheel angle value and a second steering wheel angle value, wherein the first steering wheel angle value is obtained by a first controller based on modern control theory, and the second steering wheel angle value is obtained by a second controller based on classical control theory; A steering wheel fusion angle value is obtained to control vehicle steering, wherein the steering wheel fusion angle value is obtained by fusing the first steering wheel angle value and the second steering wheel angle value.

2. The vehicle lateral control method according to claim 1, characterized in that: The first controller includes a feedback controller based on a vehicle kinematic and dynamic model; The first steering wheel angle value is obtained by the feedback controller using parameters of vehicle kinematics and dynamics models as input.

3. The vehicle lateral control method according to claim 2, characterized in that: The feedback controller includes a linear quadratic regulator; The state quantity of the linear quadratic regulator is a matrix composed of multiple vehicle lateral parameters; The objective function of the linear quadratic regulator is expressed as the integral of the state quantity, the first weight matrix, the first steering wheel angle value and the second weight matrix with respect to time; The first weight matrix is ​​a weight matrix of the state quantity, and the second weight matrix is ​​a weight matrix of the first steering wheel angle value.

4. The vehicle lateral control method according to claim 3, characterized in that: The vehicle lateral parameters include lateral error, lateral error rate, yaw error and yaw error rate.

5. The vehicle lateral control method according to claim 3, characterized in that: The parameters of the vehicle kinematics and dynamics model include at least vehicle body parameters, an angle between the vehicle and the horizontal axis in the lane map coordinate system, and a lateral error of the vehicle body.

6. The vehicle lateral control method according to claim 5, characterized in that: The vehicle body parameters include at least moment of inertia, cornering stiffness, wheelbase and vehicle mass.

7. The vehicle lateral control method according to claim 5, characterized in that: The lateral error of the vehicle body is the difference between the center of the rear axle of the vehicle and the lane reference line.

8. The vehicle lateral control method according to claim 5, characterized in that: The linear quadratic regulator uses the vehicle body parameters, the angle between the vehicle and the horizontal axis of the lane map coordinate system, and the lateral error of the vehicle body as input to obtain a state feedback control coefficient; The first steering wheel angle value is obtained according to the state feedback control coefficient and the state quantity.

9. The vehicle lateral control method according to claim 8, characterized in that: The state feedback control coefficient is obtained by calculating the linear quadratic regulator through the algebraic Riccati equation.

10. The vehicle lateral control method according to claim 1, characterized in that: The second controller includes an integral controller, which uses the lateral error of the vehicle body as an input to obtain the second steering wheel angle value.

11. The vehicle lateral control method according to claim 10, characterized in that: The lateral error of the vehicle body is the difference between the center of the rear axle of the vehicle and the lane reference line.

12. The vehicle lateral control method according to claim 1, characterized in that: The steering wheel fusion angle value is the sum of the first steering wheel angle value and the second steering wheel angle value.

13. An electronic device, characterized in that: include: at least one processor; a memory communicatively coupled to the at least one processor; The memory stores a computer program that can be executed by the at least one processor, and when the at least one processor executes the computer program, the vehicle lateral control method according to any one of claims 1 to 12 is implemented.

14. A non-volatile readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the vehicle lateral control method according to any one of claims 1 to 12 is implemented.

15. A driving assistance system, characterized in that: An electronic device comprising the electronic device described in claim 13.

16. A vehicle, characterized in that: Includes the electronic device described in claim 13 or includes the driving assistance system described in claim 15.

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