Method and device for controlling transverse illumination angle of vehicle headlamp

Abstract

The invention relates to a control method and a control device for a transverse illumination angle of a vehicle headlamp. The control method for the transverse illumination angle of the vehicle headlamp comprises the steps that current vehicle state information and an expected track are obtained; performing state estimation on the current vehicle state information by adopting a vehicle path tracking steering model, and performing solution optimization on a path tracking target function according to the vehicle attitude information of state estimation and an expected trajectory to obtain an optimal front wheel steering angle control quantity; according to the vehicle attitude information, the optimal front wheel steering angle control quantity and the expected trajectory, the left and right illumination angle objective functions are solved and optimized respectively, and optimal control quantities of left and right headlamps are obtained; and the signals are respectively sent to corresponding driving units after being converted, so that the optimization of the optimal transverse illumination angle is completed. According to the control method for the transverse illumination angle of the vehicle headlamp, the matching accuracy between the illumination angle and the actual driving path is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle dynamics and predictive control headlights, and particularly to a control method and a control device for the lateral illumination angle of a vehicle headlight. Background Art

[0002] When driving under autonomous driving or low-light conditions at night and passing through complex scenarios such as curves, sharp turns, or mountain roads, if the illumination direction of the headlight fails to be laterally adjusted in time, obvious visual blind spots are likely to occur, which will seriously affect the perception effect of the driver or the autonomous driving system, and further cause serious safety hazards. Nowadays, vehicles are generally equipped with an Adaptive Front-lighting System (AFS), which automatically controls the irradiation angle of the headlight by detecting the vehicle environment or vehicle state to provide the best lighting effect.

[0003] Its adaptive headlight system generally relies on image recognition technology. Images are collected by a forward camera to identify and analyze the information of the road ahead, so as to predict whether there is a curve and adjust the illumination direction of the vehicle lamp according to the prediction. However, the image recognition method is prone to malfunction due to the influence of environmental interference. Factors such as rainy or foggy weather, strong backlight, light reflection, and lens stains may all reduce the recognition accuracy of the image recognition technology.

[0004] Based on this, the prior art generally uses the sensor information of the vehicle itself combined with road data to dynamically control the lateral illumination angle of the headlight. Especially during autonomous driving, the system usually tries to align the irradiation direction of the headlight with the desired trajectory point (Preview Point) in the autonomous driving planned path to improve the driving vision in the night or low-light environment. It generally relies on a steering wheel angle sensor to obtain the rotation angle of the steering wheel and converts it into the steering angle of the vehicle front wheels through a linear mapping relationship, and then adjusts the lateral illumination angle of the vehicle lamp in coordination with the steering angle of the vehicle front wheels.

[0005] However, the prior art ignores the influence of dynamic factors such as steering, roll, yaw, and sharp turns of the vehicle during dynamic driving on the lateral illumination direction, resulting in a certain offset error in the calculation of the lateral illumination angle in the prior art, which causes the illumination range to deviate from the target area and the path visibility to decrease. Accordingly, the prior art cannot achieve precise illumination coverage of the lateral illumination angle for the desired trajectory point, resulting in insufficient coverage of the illumination range, which is likely to affect the perception effect of the driver or the autonomous driving system and driving safety. Summary of the Invention

[0006] Based on this, the object of the present invention is to provide a control method for the lateral illumination angle of a vehicle headlight.

[0007] A control method for the lateral illumination angle of a vehicle headlamp, comprising the following steps:

[0008] S1: Obtain the current vehicle state information and the desired trajectory; wherein, the vehicle state information includes vehicle speed, vehicle heading angle, vehicle yaw rate, vehicle steering wheel angle and vehicle position; the desired trajectory includes a sequence of desired trajectory points and path curvature within a future prediction time domain;

[0009] S2: Use a vehicle path tracking steering model to perform state estimation on the current vehicle state information to obtain vehicle attitude information within a future time domain;

[0010] S3: Solve and optimize the path tracking objective function according to the vehicle attitude information and the desired trajectory within a future time domain to obtain an optimal front wheel steering angle control quantity within a future time domain;

[0011] S4: Solve and optimize the left and right illumination angle objective functions respectively according to the vehicle attitude information, the optimal front wheel steering angle control quantity and the desired trajectory within a future time domain to obtain control quantities for the optimal left and right headlamps within a future time domain;

[0012] S5: Perform signal conversion on the optimal front wheel steering angle control quantity and the control quantities for the optimal left and right headlamps at a first moment to obtain actual control signals for the steering angle and the headlamps, and send them to corresponding drive units respectively to complete the optimization of the optimal lateral illumination angle.

[0013] The control method for the lateral illumination angle of the vehicle headlamp according to the present invention, compared with the prior art, predicts the future attitude of the vehicle through a path tracking steering model, combines the prediction result with the path tracking objective function, and optimizes to obtain an optimal front wheel steering angle control quantity; subsequently, based on the steering angle control quantity, vehicle attitude information and desired trajectory, the illumination angle objective functions for the left and right headlamps are respectively independently optimized and solved, so as to realize the dynamic coordination of illumination control and path tracking, effectively improve the matching accuracy between the illumination angle and the actual driving path, and further enhance the road perception ability and driving safety of the vehicle under night or complex working conditions.

[0014] Further, the specific differential equation structure of the vehicle path tracking steering model is represented as follows:

[0015]

[0016] In the formula, represents the change rate of vehicle attitude information, and its x(t) represents the vehicle attitude information at the t-th moment, that is, the vehicle state vector, which is specifically represented as follows:

[0017]

[0018] In the formula, v y is the lateral velocity; r is the yaw rate; ψ L is the heading angle error; y L is the lateral displacement; δ represents the steering wheel angle, i.e., the front wheel angle; represents the steering wheel angular velocity;

[0019] M d is the operating torque of the driver or the autonomous driving system; w(t) is the lateral disturbance input at the t-th moment; A is the state transition matrix, and its specific representation is as follows:

[0020]

[0021] Wherein,

[0022]

[0023] In the formula, v x is the forward velocity; l s is the preview distance, which is used to represent the Euclidean distance between the vehicle center of mass and the desired trajectory point; C f and C r are the cornering stiffnesses of the front and rear wheels respectively; m represents the vehicle mass; l f and l r are the distances from the vehicle center of mass to the front axle and the rear axle of the vehicle respectively; I z is the moment of inertia of the vehicle about the z-axis perpendicular to the ground; I S is the equivalent moment of inertia of the steering system; η t is the contact length between the tire and the ground; R S is the steering system gear ratio; B S is the steering wheel angle damping coefficient; M d represents the operating torque for the steering system;

[0024] B is the control input gain matrix, and its specific representation is as follows:

[0025]

[0026] B w is the disturbance input gain matrix, and its specific representation is as follows:

[0027]

[0028] In the formula, l w represents the distance from the acting point of the lateral force to the vehicle center of mass.

[0029] Accordingly, for the vehicle path tracking steering model of the present invention, by integrating vehicle lateral dynamics (i.e., the two-degree-of-freedom bicycle model), the dynamic equation of lateral displacement (i.e., the lateral offset trend between the vehicle's center of mass and the path during the steering process), and the front-wheel steering dynamic equation (i.e., the dynamic characteristics of the front-wheel controlled response and the self-aligning torque), the system can more comprehensively and accurately depict the vehicle's attitude evolution trend during the path tracking process, so as to estimate the vehicle's attitude information in the future time domain with high precision, and further provide high-quality dynamic input data for subsequent path tracking optimization and lighting angle control, effectively improving the response forward-looking, path matching accuracy, and system robustness of the control system.

[0030] Further, the specific structure of the path tracking objective function is expressed as follows:

[0031]

[0032] In the formula, J track is the path tracking objective function; T represents the future prediction time domain considered under the current control period;

[0033] w y is the weight coefficient of the lateral displacement error; e y (s|t k ) is the lateral displacement error corresponding to the desired trajectory point s, which is obtained by calculating through the vehicle steering kinematic error model;

[0034] is the weight coefficient of the heading angle error; is the heading angle error corresponding to the desired trajectory point s, which is obtained by calculating through the vehicle steering kinematic error model;

[0035] w δ is the weight coefficient of the steering control; δ(s|t k ) is the steering wheel angle corresponding to the desired trajectory point s, that is, the control input;

[0036] Among them, the minimization solution expression for minimizing the optimization path tracking objective function is as follows:

[0037]

[0038] In the formula, represents the optimal front-wheel steering angle control quantity corresponding to the t k th moment in the future time domain; argmin δ J track (t k ) is used to represent that under all potential front-wheel steering angle control input sequences, obtain the path tracking objective function J track (t k)The control amount of the front wheel steering angle corresponding to reaching the minimum value;

[0039] Among them, the differential equation of the vehicle steering kinematic error model is expressed as follows:

[0040]

[0041] In the formula, is the path progress change rate; is the lateral error change rate; is the heading error change rate; ρ is the path curvature.

[0042] Accordingly, the path tracking objective function of the present invention takes three items, namely vehicle lateral error, heading angle error, and control input fluctuation, as joint optimization indexes, and combines the vehicle steering kinematic error model to model the dynamic evolution process of the error with the path progress, so that on the basis of the vehicle attitude information predicted by the path tracking steering model, the geometric deviation of the vehicle relative to the desired path can be accurately sensed, and thus the forward compensation of the path deviation trend can be realized by generating the optimal front wheel steering angle control amount, significantly improving the accuracy, stability of the path tracking control and the smoothness of the steering control.

[0043] Furthermore, the specific expressions of the left lighting angle objective function and the right lighting angle objective function are as follows:

[0044]

[0045]

[0046] In the formula, J L , J R are the left lighting angle objective function and the right lighting angle objective function respectively; w θL , w θR are the weight coefficients of the left lighting error and the right lighting error respectively; θ L (s|t k ) and θ R (s|t k ) are the actual lighting angles of the left headlight and the right headlight respectively, and are specifically obtained through iterative calculation by the angle adjustment change rate . The differential equation of the angle adjustment change rate of the left lighting angle is expressed as follows:

[0047]

[0048] In the formula, a L represents the state transition coefficient of the left headlight stepping motor; b L represents the control gain coefficient of the left headlight stepping motor; u L(s|t k ) is the control quantity of the left headlight at the desired trajectory point s;

[0049] The differential equation of the angular adjustment change rate of the right lighting angle is expressed as:

[0050]

[0051] In the formula, a R represents the state transition coefficient of the right headlight stepping motor; b R represents the control gain coefficient of the right headlight stepping motor; u R (s|t k ) is the control quantity of the right headlight at the desired trajectory point s;

[0052] φ L (s|t k ), φ R (s|t k ) are the ideal lighting angles on the left and the right calculated according to the desired trajectory and vehicle attitude information at the desired trajectory point s;

[0053] Among them, the minimization solution expression for minimizing the objective function of optimizing the left and right lighting angles is as follows:

[0054]

[0055] In the formula, represents the optimal control quantity of the left headlight corresponding to the t k th moment in the future time domain; is used to represent that under all potential control input sequences of the left headlight, the control quantity of the left headlight corresponding to minimizing the objective function J E (t k ) is obtained, and this control quantity is used as the optimization output for actual lighting control execution;

[0056] Among them, the calculation of the initial values of the actual lighting angles θ L (s|t0) of the left headlight and θ R (s|t0) of the right headlight is shown as follows:

[0057] By adopting the steering kinematic relationship of the vehicle to convert the corresponding optimal front wheel steering angle control quantity to obtain the current vehicle heading angle, and using it as the initial value of the actual lighting angles of the left headlight and the right headlight, the specific representation of the steering kinematic relationship of the vehicle is as follows:

[0058]

[0059] In the formula, respectively represent the change rates of the x-axis coordinate and the y-axis coordinate in the global coordinate system of the vehicle's center of mass; represents the change rate of the vehicle's heading angle, and its specific representation is as follows:

[0060]

[0061] wherein, the vehicle's yaw angular velocity r is approximately equal to the change rate of the vehicle's heading angle that is

[0062] Based on the vehicle attitude information and the optimal front wheel steering angle control quantity, the present invention independently optimizes the lighting angle objective functions of the left and right headlamps respectively, and realizes that on the basis of generating steering compensation during path tracking, the actual lighting angles of the left and right headlamps are further stably directed to their respective corresponding ideal lighting directions, that is, the preview points in the expected trajectory.

[0063] The control mechanism that independently optimizes the lighting angles respectively effectively compensates for the lighting offset phenomenon caused by the dynamic steering of the vehicle body, enables the left and right vehicle lamps to flexibly adjust the lighting range according to factors such as path curvature and preview distance, thereby significantly improving the coverage accuracy of the lighting for the trajectory and the perception continuity of the road ahead.

[0064] Accordingly, through the independent optimization of the left and right lighting controls, the present invention not only enhances the road visibility in complex scenarios such as night, low light, and sharp curves, but also further improves the vehicle's environmental perception ability and safety during path tracking.

[0065] A control device for the lateral lighting angle of a vehicle headlamp, comprising a vehicle state-path trajectory acquisition unit, a vehicle attitude estimation unit, a path tracking predictive control unit, a predictive control unit for the headlamp, and a control signal conversion unit;

[0066] The vehicle state-path trajectory acquisition unit is used to acquire the current vehicle state information and the expected trajectory; wherein, the vehicle state information includes vehicle speed, vehicle heading angle, vehicle yaw angular velocity, vehicle steering wheel angle, and vehicle position; the expected trajectory includes a sequence of expected trajectory points and path curvature within a future prediction time domain;

[0067] The vehicle attitude estimation unit is used to perform state estimation on the current vehicle state information by using a vehicle path tracking steering model to obtain the vehicle attitude information within a future time domain;

[0068] The path tracking predictive control unit is used to solve and optimize the path tracking objective function according to the vehicle attitude information and the expected trajectory within a future time domain to obtain the optimal front wheel steering angle control quantity within a future time domain;

[0069] The predictive control unit of the headlamp is configured to solve and optimize the left and right lighting angle objective functions respectively according to the vehicle attitude information, the optimal front wheel steering angle control quantity, and the desired trajectory within a future time domain, so as to obtain the control quantities of the optimal left and right headlamps within the future time domain;

[0070] The control signal conversion unit is configured to perform signal conversion on the optimal front wheel steering angle control quantity at a first moment and the control quantities of the optimal left and right headlamps, obtain the actual control signals of the steering angle and the headlamps, and send them to the corresponding drive units respectively to complete the optimization of the optimal lateral lighting angle.

[0071] For better understanding and implementation, the present invention will be described in detail below with reference to the accompanying drawings. Description of the Drawings

[0072] Figure 1 It is a schematic diagram of the simple structure of the control device for the lateral lighting angle described in the present invention;

[0073] Figure 2 It is a schematic diagram of the simple process of the control method for the lateral lighting angle of the vehicle headlamp described in the present invention. Detailed Embodiment

[0074] In order to solve the problem that the prior art cannot achieve accurate lighting coverage of the desired trajectory points, resulting in the lighting effect not reaching the optimal, the present invention obtains the current vehicle state information and the desired trajectory, and uses a vehicle path tracking steering model to perform state estimation on the vehicle state information to obtain the vehicle attitude information within a future time domain; then, according to the vehicle attitude information and the desired trajectory, the model predictive control algorithm (Model Predictive Control, MPC) is used to solve and optimize the path tracking objective function to obtain the optimal front wheel steering angle control quantity within the future time domain; and according to the vehicle attitude information, the optimal front wheel steering angle control quantity, and the desired trajectory, the MPC is used to solve and optimize the left and right lighting angle objective functions respectively to obtain the optimal left and right headlamp control quantities within the future time domain; finally, signal conversion is performed on the optimal front wheel steering angle control quantity at the first moment and the compensation control quantities of the left and right headlamps, and the actual control signals of the steering angle and the headlamps after signal conversion are sent to the corresponding drive units to complete the optimization of the optimal lateral lighting angle.

[0075] Accordingly, by introducing a vehicle path tracking steering model, the present invention comprehensively considers steering dynamics factors such as yaw, lateral acceleration, and centroid offset, realizes high-precision prediction of the lateral attitude change of the vehicle, and uses it as the core reference basis for headlamp control, enabling the adaptive headlamp system to respond to the dynamic changes during steering in real time, thereby improving the accuracy of predicting the vehicle head orientation under complex road conditions and providing forward-looking attitude information for lighting optimization in scenarios such as curved road sections;

[0076] Meanwhile, by separately constructing three independent objective functions for path tracking and left and right lighting angles and jointly optimizing and solving them, dynamic collaborative control of lighting and the path is achieved, enabling the lighting angle to accurately match the actual motion trend of the vehicle, significantly improving the lighting coverage and utilization efficiency of the headlamp, ensuring the continuity of the driving vision and the lighting integrity of key areas, thereby enhancing the driving safety and stability at night or under complex conditions.

[0077] Based on the above design, the present invention proposes a control method for the lateral lighting angle of a vehicle headlamp, and a control device for the lateral lighting angle of a vehicle headlamp is proposed based on this method.

[0078] The control device for the lateral lighting angle of the vehicle headlamp includes a vehicle state-path trajectory acquisition unit 1, a vehicle attitude estimation unit 2, a path tracking predictive control unit 3, a predictive control unit 4 for the headlamp, and a control signal conversion unit 5.

[0079] The vehicle state-path trajectory acquisition unit 1 is used to execute step S1: acquire the current vehicle state information and desired trajectory.

[0080] Specifically, the vehicle state information includes vehicle speed, vehicle heading angle, vehicle yaw rate, vehicle steering wheel angle, and vehicle position.

[0081] Among them, the vehicle speed is obtained by fusing the measurements of a wheel speed sensor and an accelerometer in an inertial measurement unit (IMU), and it includes the forward speed v of the vehicle in the vehicle coordinate system x and the lateral speed v y , which are respectively used to represent the motion components of the vehicle's center of mass along the x-axis and along the y-axis in a two-dimensional plane. Among them, the wheel speed sensor is generally installed on the wheel bearing or wheel speed assembly for measuring speed information; the inertial sensor is usually installed near the structural center or center of mass of the vehicle chassis to improve the stability and accuracy of the data.

[0082] The vehicle heading angle represents the orientation angle of the vehicle relative to the due north direction in the geodetic reference coordinate system, and is obtained by fusing the measurements of a gyroscope in an inertial measurement unit (IMU) and the positioning data of a positioning system.

[0083] The vehicle yaw rate is obtained by measuring a gyroscope in an inertial measurement unit (IMU), and is used to characterize the rotation rate of the vehicle body around the vertical axis, that is, the angular velocity of the vehicle's yaw motion around the vertical axis (z-axis) perpendicular to the ground.

[0084] The steering wheel angle of the vehicle is measured by a steering angle sensor or an angle encoder built into the Electric Power Steering (EPS) system, which is the actual steering input angle of the driver or the autonomous driving system at the current moment.

[0085] The vehicle position is obtained through an on-vehicle positioning system, which is used to provide the position coordinate information of the vehicle in the geographical coordinate system.

[0086] Among them, the desired trajectory is generated by a path planning module in the autonomous driving system. The path planning module usually calculates by obtaining high-precision map information, current environmental perception data, and driving task objectives, and combines path planning algorithms to generate trajectory parameters such as a sequence of desired trajectory points and path curvature within the future prediction time domain for the control system to perform trajectory tracking control.

[0087] It should be noted that due to differences in the path planning algorithms used in different autonomous driving systems, the forms and accuracies of the planned desired trajectories are also different; and the path planning algorithm itself is not the invention of this application, so this application does not make specific limitations on it, nor does it elaborate on the generation method and calculation process of the desired trajectory.

[0088] The vehicle attitude estimation unit 2 is used to execute step S2: use the vehicle path tracking steering model to perform state estimation on the current vehicle state information to obtain the vehicle attitude information within the future time domain.

[0089] Specifically, the vehicle path tracking steering model is a set of continuous-time state space equations, and the structure of its specific differential equation is expressed as follows:

[0090]

[0091] In the formula, represents the change rate of the vehicle attitude information, that is, the first derivative of the state vector x(t) in the time dimension. Among them, x(t) represents the vehicle attitude information at the t-th moment, which is also the vehicle state vector, specifically:

[0092]

[0093] In the formula, v y is the lateral speed, that is, the lateral speed component of the vehicle center of mass in these two coordinate systems, which is used to reflect whether the vehicle has a tendency of sideslip or lateral displacement; r is the yaw angular velocity, which is used to reflect the steering speed or turning tendency of the vehicle body; δ represents the steering wheel angle; ψ L is the heading angle error, that is, the angle error between the current vehicle heading angle and the tangent direction of the desired trajectory, which is used to reflect the direction difference between the vehicle driving direction and the desired trajectory; y Lis the lateral displacement, which is used to represent the deviation between the vehicle and the desired trajectory point at the same moment during the steering movement; represents the angular velocity of the steering wheel, that is, the first derivative of the steering wheel angle;

[0094] M d is the operating torque of the driver or the autonomous driving system, that is, the operating torque acting on the steering system, which is the input variable of vehicle steering control. Its steering system is affected by damping characteristics; w(t) is the lateral disturbance input at the t-th moment, that is, the lateral disturbing force acting on the vehicle's center of mass or tires, which is used to fit the system noise term that is not directly controlled by the controller but will affect the vehicle's attitude;

[0095] Its A, B, B w are the state transition matrix, the control input gain matrix, and the disturbance input gain matrix respectively, and their specific values are derived and constructed through the vehicle steering dynamics model;

[0096] The vehicle steering dynamics model includes a simplified two-degree-of-freedom bicycle model, the dynamic equation of the lateral displacement, and the front-wheel steering dynamics equation of the vehicle;

[0097] Among them, the simplified two-degree-of-freedom bicycle model is used to describe the change of the overall attitude of the vehicle, and its specific derivation is as follows:

[0098] According to the two-degree-of-freedom bicycle model, we have:

[0099]

[0100] In the formula, is the mass acceleration term in the lateral direction, m represents the vehicle mass, is the lateral acceleration of the vehicle, which is based on Newton's second law, that is, F = ma; -mv x r represents the centrifugal term, that is, when the vehicle yaws (steers), an outward centrifugal tendency is generated at the center of mass, which is used to provide inertial compensation for the lateral acceleration; F l represents the lateral disturbing force, which is used to reflect the uncertainty of the system, that is, the system noise term, and is generally used to fit the external lateral disturbing force received by the vehicle during movement, such as crosswind; l w represents the distance from the acting point of the lateral force to the vehicle's center of mass, which is used to combine with the lateral disturbing force to form a disturbing torque, thereby affecting the yaw acceleration of the vehicle;

[0101] represents the yaw inertia term, which is used to construct the angular momentum balance equation, that is, to balance the rotational inertia and the external torque during the vehicle's turning. Its I z is the moment of inertia of the vehicle about the z-axis perpendicular to the ground; l f and l rThey are the distances from the vehicle's center of mass to the front and rear axles of the vehicle respectively, which are used to determine the lever arm length, thereby calculating the influence of the moment on yaw;

[0102] F yf and F yr They are the lateral forces of the front and rear wheels respectively, and their specific calculations are as follows:

[0103]

[0104] In the formula, C f and C r are the cornering stiffnesses of the front and rear wheels respectively, which are used to represent the sensitivity of the tire lateral force to the change of the sideslip angle, that is, the linear relationship coefficient between the lateral force and the sideslip angle, so as to reflect the self-aligning force trend generated by the sideslip angle when the tire is steering or skidding; θ vf and θ vr represent the tire sideslip angles of the front and rear wheels respectively, which are used to represent the angle between the actual driving direction of the tire (the direction of the front wheel speed vector) and the tire orientation, and their specific calculations are as follows

[0105]

[0106] In the formula, δ f is the geometric angle of the front wheel. For the sake of simplifying the calculation, the present invention makes that is, the geometric angle of the front wheel is approximately equal to the steering wheel angle.

[0107] Accordingly, it substitutes the lateral forces and tire sideslip angles of the front and rear wheels into the two-degree-of-freedom bicycle model and simplifies it to obtain a simplified two-degree-of-freedom bicycle model, which is specifically expressed as follows:

[0108]

[0109] The dynamic equation of the lateral displacement is used to describe the lateral offset of the vehicle relative to the path, and its specific mathematical expression is as follows:

[0110]

[0111] In the formula, represents the first derivative of the lateral displacement, which is used to describe the state change of the lateral displacement y L ; l s is the preview distance, which is used to represent the Euclidean distance between the vehicle's center of mass and the desired trajectory point, and the preview distance l s changes dynamically with the vehicle speed and path curvature. Specifically, it can be calculated by a fixed ratio or an adaptive weighting algorithm. In addition, different desired trajectory points can be selected as the lighting target points according to different scenarios. Therefore, the preview distance l sThere are different calculation methods, and the present invention does not specifically limit the calculation method of the preview distance herein.

[0112] The front-wheel steering dynamics equation of the vehicle is used to describe the dynamic process of the steering input on the front-wheel angle response, and its mathematical model is expressed as follows:

[0113]

[0114] In the formula, represents the response inertia term of the steering system to the front-wheel corner acceleration, and its I S is the equivalent moment of inertia of the steering system, which is usually used to characterize the inertial response ability of the control input to the angular acceleration change.

[0115] It should be noted that in the manual driving scenario, this I S corresponds to the moment of inertia generated by the steering wheel angle applied by the driver; while in the autonomous driving scenario, I S can be regarded as the moment of inertia generated by the target corner controlled by the electronically controlled steering system; in the present invention, for unified modeling processing, I S is regarded as the equivalent moment of inertia generated by the "direction control input", which can cover the moment of inertia generated by the steering wheel angle in manual driving and the steering wheel angle under the control of the autonomous driving system;

[0116] is the lateral velocity coupling term, which is used to characterize the influence of the vehicle lateral slip (i.e., non-ideal path tracking) state on the front-wheel self-aligning force. This lateral feedback acts on the steering system through the grounding characteristics of the tire and the transmission ratio; η t is the contact length between the tire and the ground, and the larger its value, the stronger the friction contact effect; R S is the steering system transmission ratio, which is used to represent the angle ratio between the steering wheel and the wheel;

[0117] is the yaw rate coupling term, which is used to characterize the dynamic influence of the lateral self-aligning force caused by the change of the front-wheel side slip angle on the steering system when the vehicle rotates around the vertical axis;

[0118] is the tire self-aligning torque term, which is used to reflect the passive self-aligning torque generated by the side slip stiffness after the tire deflects. The direction of this torque will try to restore the front-wheel angle to the center position;

[0119] is the steering damping term, which is used to represent the internal damping force received by the steering wheel during rotation. B S is the steering wheel angle damping coefficient, which is a constant;

[0120] To control the input torque term, which is used to represent the target steering torque applied by the driver or the autonomous driving system.

[0121] Based on the simplified bicycle model with two degrees of freedom, the dynamic equation of the lateral displacement, and the front-wheel steering dynamic equation of the vehicle, the state transition matrix A, the control input gain matrix B, and the disturbance input gain matrix B w are specifically represented as follows:

[0122]

[0123] Where:

[0124]

[0125]

[0126] Accordingly, the present invention constructs a vehicle path tracking steering model through a simplified bicycle model with two degrees of freedom, the dynamic equation of the lateral displacement, and the front-wheel steering dynamic equation, so that the model can fully consider key dynamic factors such as vehicle attitude changes, lateral offsets under the desired trajectory, and the restoring torque and lateral force generated by the front and rear wheels during the vehicle steering process during the state estimation process, thereby realizing a highly accurate prediction of the vehicle attitude information in the future time domain, and significantly improving the forward-looking and dynamic adaptability of the collaborative optimization of path tracking and lighting angle based on model predictive control (MPC).

[0127] It should be noted that in order to perform discrete prediction using the vehicle path tracking steering model in a computer, it is necessary to discretize the differential equation of the above vehicle path tracking steering model to obtain the change expressions corresponding to different times t in the time domain, so that the computer can directly use the discretized vehicle path tracking steering model for prediction. It can be discretized by using numerical integration methods commonly used in the art such as the Euler method or linear interpolation, and the specific implementation method will not be elaborated here.

[0128] The path tracking prediction control unit 3 is used to execute step S3: according to the vehicle attitude information and the desired trajectory in the future time domain, solve and optimize the path tracking objective function to obtain the optimal front-wheel steering angle control quantity in the future time domain.

[0129] Specifically, the path tracking objective function is used to minimize the lateral position deviation and the heading angle deviation between the vehicle and the desired trajectory during the path tracking control process, and suppress excessive steering input fluctuations, thereby improving the accuracy and control smoothness of the path tracking. Its specific representation is as follows:

[0130]

[0131] In the formula, Jtrack is the path tracking objective function, which evaluates the deviation generated during the path tracking process correspondingly as the desired trajectory point s advances;

[0132] is the lateral displacement error term, which is used to constrain the lateral offset degree of the vehicle's center of mass position relative to the center line of the desired trajectory, w y is the weight coefficient of the lateral displacement error and is an empirical coefficient; e y (s|t k ) is the lateral displacement error corresponding to the desired trajectory point s, which is used to represent the shortest distance from the vehicle's center of mass to the actual desired trajectory point under the desired trajectory point s at the same moment, and is obtained by calculating through the vehicle steering kinematic error model;

[0133] is the heading angle error term, which is used to suppress the angular error of the vehicle's heading deviating from the desired trajectory direction and improve the consistency and stability of path tracking. is the weight coefficient of the heading angle error and is an empirical coefficient; is the heading angle error corresponding to the desired trajectory point s, which is used to represent the included angle error between the vehicle's heading angle and the direction of the desired trajectory point under the desired trajectory point s at the same moment, and is obtained by calculating through the vehicle steering kinematic error model;

[0134] w δ ·δ 2 (s|t k ) is the steering control term, which is used to suppress the volatility of the steering control input, prevent the impact of violent manipulation on the vehicle's stability and mechanical system, and at the same time maintain the smoothness of the control output, w δ is the weight coefficient of the steering control and is an empirical coefficient; δ(s|t k ) is the steering wheel angle corresponding to the desired trajectory point s, which is also the front wheel angle and serves as the control input in the optimization solution process.

[0135] Next, by minimizing the path tracking objective function, the optimal front wheel angle control quantity in the future time domain is obtained, and its minimization solution expression is as follows:

[0136]

[0137] In the formula, represents the optimal front wheel angle control quantity corresponding to the t k th moment in the future time domain; T represents the future prediction time domain considered under the current control period, and its time domain length is a user-defined value; argmin δ J track (t k ) is used to represent that under all potential front wheel angle control input sequences, the target function J track(t k )Reach the minimum value of the corresponding front wheel steering angle control amount, and use it as the optimized control output.

[0138] Among them, when minimizing the path tracking objective function to solve the optimization, the optimization constraint conditions are followed, and the specific optimization constraint conditions are expressed as follows:

[0139]

[0140] In the formula, x(t|t k ) = x(t k ) is the initial state constraint, which is used to ensure that the starting point of the optimization is the real state rather than the predicted data; is the state transition constraint, which is used to represent that the evolution of the vehicle state in the future time domain must satisfy the vehicle path tracking steering model; |δ(t|t k )| ≤ δ max and are respectively the maximum allowable front wheel steering angle δ max and the maximum front wheel steering angle rate constraints, which specifically depend on the geometric limit of the steering system, the dynamic performance of the motor, etc., and are constants; 0 ≤ v x (t|t k ) ≤ v max is the vehicle longitudinal speed constraint, which is used to constrain the minimum speed and the maximum speed v max of the vehicle in the longitudinal direction.

[0141] Among them, the vehicle steering kinematic error model is used to describe the deviation degree of the vehicle attitude information relative to the desired trajectory, and its differential equation is expressed as follows:

[0142]

[0143] In the formula, is the path progress change rate, which is used to represent the forward speed of the vehicle in the desired trajectory; is the lateral error change rate, which is used to reflect the lateral offset trend of the vehicle centroid relative to the center line of the desired trajectory; is the heading error change rate, which is used to measure the relative steering dynamics between the yaw angular velocity r and the path curvature ρ, and the path curvature ρ is used to represent the geometric bending degree of the desired trajectory.

[0144] It should be noted that the prediction process of the error trajectory is gradually calculated in the time domain by combining the vehicle steering kinematic error model on the basis of the predicted vehicle attitude information. At the same time, in order to enable this error model to participate in the optimization process of the path tracking objective function in cooperation with the predicted trajectory, it is necessary to discretize it, so as to obtain the discrete expression form of the error evolving with time or path progress on the predicted path, that is, ey (s|t k ), The discretization process can be implemented by conventional numerical integration methods such as the Euler method and linear interpolation, which are the conventional operation means of those skilled in the art. Therefore, the present invention does not make specific limitations thereon.

[0145] In addition, the error model is used to quantify the geometric deviation between the vehicle attitude information and the desired path, and the vehicle attitude information itself is dynamically predicted and generated by the vehicle path tracking steering model. The two act together on the solution process of the path tracking objective function, constituting the core modeling basis of path tracking control.

[0146] Accordingly, the path tracking objective function constructed by the present invention relies on the predicted results of the vehicle attitude within the future time domain of the vehicle path tracking steering model, and combines with the desired trajectory. Taking the lateral error, heading angle error and front wheel steering angle control amount as the main optimization indexes, it comprehensively reflects the dynamic deviation degree between the vehicle attitude and the path. Thus, by minimizing this objective function, an optimal front wheel steering angle control sequence can be solved within the prediction time domain, thereby significantly improving the control accuracy and dynamic stability of the autonomous vehicle during the path tracking process, achieving a smoother steering response, ensuring the stable driving of the vehicle, and effectively reducing the path deviation risk.

[0147] Meanwhile, the optimal front wheel steering angle control amount can also be used as the input reference quantity for optimizing the lighting control, and further used to solve the objective lighting angle objective function of the left and right front headlights, realizing the collaborative optimization of path tracking and lighting control.

[0148] The predictive control unit 4 of the headlight is used to execute step S4: According to the vehicle attitude information, the optimal front wheel steering angle control amount and the desired trajectory within the future time domain, optimize and solve the left and right lighting angle objective functions respectively, and obtain the control amounts of the optimal left and right headlights within the future time domain.

[0149] Specifically, the left lighting angle objective function and the right lighting angle objective function are used to optimize the maximization of the lighting direction coverage, and their specific expressions are as follows:

[0150]

[0151] In the formula, J L , J R are the left lighting angle objective function and the right lighting angle objective function respectively;

[0152] w θL ·(θ L (s|t k ) - φ L (s|t k )) 2is the left - hand lighting direction error term, which is used to measure the actual lighting angle θ of the left - hand headlamp under the expected trajectory point s L (s|t k ) and the ideal lighting angle φ L (s|t k ) deviation; w θL is the weight coefficient of the left - hand lighting error, which is used to control the influence degree of this error in the objective function; θ L (s|t k ) is the actual lighting angle of the left - hand headlamp, which is obtained by iterative calculation through the angular adjustment change rate of the left - hand lighting angle. The differential equation of the angular adjustment change rate of the left - hand lighting angle is expressed as follows:

[0153]

[0154] In the formula, a L represents the state - transition coefficient of the left - hand headlamp stepper motor, which is a constant; b L represents the control gain coefficient of the left - hand headlamp stepper motor, which is a constant; u L (s|t k ) is the control quantity of the left - hand headlamp under the expected trajectory point s; while the differential equation of the angular adjustment change rate of the right - hand lighting angle is expressed as:

[0155]

[0156] In the formula, a R represents the state - transition coefficient of the right - hand headlamp stepper motor, which is a constant; b R represents the control gain coefficient of the right - hand headlamp stepper motor, which is a constant; u R (s|t k ) is the control quantity of the right - hand headlamp under the expected trajectory point s;

[0157] φ L (s|t k ) is the ideal lighting angle of the left - hand side calculated according to the expected trajectory and vehicle attitude information under the expected trajectory point s, which is used to represent the angle required for the left - hand headlamp to illuminate the expected trajectory point in the expected trajectory at the same moment. Among them, this ideal lighting angle is generated by the path - planning module according to the current expected trajectory point and preview strategy, and dynamically changes according to the preview distance l s . Its calculation method can be flexibly adjusted according to different scenarios, and the present invention does not make specific limitations; and the ideal lighting angle φ of the right - hand side R (s|t k ) is the same, and the present invention does not specifically elaborate;

[0158] is the left - side lighting angle adjustment penalty term, corresponding to w rL is the weight coefficient of the angle adjustment change rate of the left - side lighting angle, which is used to ensure the smoothness of lighting control and prevent visual blind spots or jitters caused by lighting jumps.

[0159] Next, by minimizing the left - side and right - side lighting angle objective functions, the control quantities of the optimal left - and right - side headlamps in the future time domain are obtained. The minimization solution expression is as follows:

[0160]

[0161] In the formula, represents the control quantity of the optimal left - side headlamp corresponding to the t k th moment in the future time domain; is used to represent that under all potential control input sequences of the left - side headlamp, the control quantity of the left - side headlamp corresponding to minimizing the objective function J R (t k ) is obtained, and this control quantity is used as the optimization output for actual lighting control execution; the parameter meanings of the minimization solution expression of the right - side lighting objective function structure are the same as those of the left - side, so they will not be elaborated here.

[0162] Among them, when solving and optimizing the left - side and right - side lighting angle objective functions, the lighting optimization constraint conditions are followed. The lighting optimization constraint conditions are specifically expressed as follows:

[0163]

[0164] In the formula, θ lmax represents the maximum adjustable angle of the headlamp in the lateral direction, which is used to avoid exceeding the physical limit of the lighting system; represents the maximum adjustable angular velocity of the headlamp, which is used to limit the too - fast angle change and prevent damage to the hardware or visual blind spots caused by lighting jumps.

[0165] Among them, since the headlamp is related to the vehicle body rotation, when the front - wheel steering angle of the vehicle changes, the headlamp will be driven to change, that is, the initial value of the headlamp is consistent with the vehicle heading angle; therefore, the initial value of the actual lighting angle θ L (s|t0) of the left - side headlamp is obtained by converting the corresponding optimal front - wheel steering angle control quantity using the vehicle steering kinematic relationship to obtain the current vehicle heading angle, and this vehicle heading angle is used as the initial value of the actual lighting angle of the left - side headlamp. The specific expression of the vehicle steering kinematic relationship is as follows:

[0166]

[0167] In the formula, respectively represent the change rates of the x-axis coordinate and the y-axis coordinate in the global coordinate system of the vehicle's center of mass, that is, the first derivative of the position coordinates of the vehicle's center of mass in the global coordinate system; represents the change rate of the vehicle's heading angle, and its specific representation is as follows:

[0168]

[0169] It should be noted that although the vehicle's heading angle (representing the vehicle head direction) is not exactly the same as the vehicle's yaw angle, since the change of the heading angle is mainly affected by the vehicle's rotation, the vehicle's yaw angular velocity is approximately equal to the change rate of the vehicle's heading angle in this invention, that is, a simplified treatment is made at low speeds or when the side slip angle is small. Thus, when calculating the current lighting direction of the vehicle or deriving the ideal lighting angle, the change trend of the vehicle's orientation can be quickly obtained directly from the vehicle's speed and steering information, so as to unify the angle reference basis in path tracking and lighting control, and improve the resolvability and real-time performance of the overall control system.

[0170] Accordingly, based on the optimal front wheel steering angle control quantity, combined with the vehicle steering kinematic model, the heading angle of the current vehicle is calculated in this invention and used as the initial value of the actual lighting angle of the headlamp, so as to construct the starting state of lighting control; then, the left-side and right-side lighting angle objective functions are respectively used to measure the deviation between the actual lighting angle and the ideal lighting angle, and to ensure that when the objective function is minimized, the lighting direction can accurately cover the expected trajectory points; at the same time, to minimize the above objective function, this invention further introduces the state transition model between the lighting angle and the control input, and recursively predicts the lighting angles at future moments through a first-order linear differential equation, so that the optimization process has good forward-looking and dynamic adaptability, thus significantly improving the environmental perception ability and path tracking safety of autonomous vehicles in low-light, curved or asymmetric road environments.

[0171] The control signal conversion unit 5 is used to execute step S5: perform signal conversion on the optimal front wheel steering angle control quantity at the first moment and the control quantities of the optimal left and right headlamps, obtain the actual control signals of the steering angle and the headlamps, and send them to the corresponding drive units respectively to complete the optimization of the optimal lateral lighting angle.

[0172] Specifically, extract the optimal front wheel steering angle control quantity within the future time domain, and among the control quantities of the optimal left and right headlamps, the optimal front wheel steering angle control quantity and the control quantities of the optimal left and right headlamps at the first moment.

[0173] And convert the optimal front wheel steering angle control quantity and the control quantities of the optimal left and right headlamps at the first moment into the actual drive signals of the corresponding drive units to obtain the steering angle control signal and the actual control signals of the left and right headlamps.

[0174] Among them, the steering angle control signal can be converted into an angle encoding signal or a current command through the electric power steering system (EPS) interface; the actual control signal of the headlight is generally driven by a stepper motor and can be converted by using PWM (pulse width modulation) or a current signal.

[0175] Next, the control signals are sent to the vehicle's steering actuator (such as the steering wheel) and the stepper motors of the left and right headlights, respectively, so that they complete physical adjustments according to the received control signals, thereby achieving fine control of the current vehicle's steering and lighting angles and optimizing the optimal lateral lighting angle.

[0176] Finally, after the control signal is executed, step S1 is re-executed to collect the latest vehicle status information and restart the prediction optimization process.

[0177] Among them, this mechanism is based on the receding horizon control strategy, that is, in each control cycle, only the first set of control quantities in the prediction time domain is executed, and the optimization calculation is re-performed based on the latest state information in the next cycle. Therefore, by only reasonably increasing the control cycle frequency, a higher-precision lighting control response can be achieved in fast-changing curved road conditions or complex environments, thereby significantly improving the environmental perception continuity and overall driving safety of the autonomous driving system at night, in low illumination or on sharp curves.

[0178] Compared with the prior art, the present invention optimizes and solves the optimal front wheel steering angle control value through the vehicle path tracking steering model, combined with the vehicle's current posture information and the expected trajectory, to ensure that the vehicle runs stably along the expected path under dynamic conditions; then, based on the optimal front wheel steering angle and vehicle posture, the lighting angle objective functions of the left and right headlights are independently optimized and controlled, thereby achieving precise alignment of the lighting direction with the expected trajectory point (the pre-aiming point for lighting in the expected trajectory point), significantly improving the lighting coverage of the vehicle during path tracking under complex conditions such as night, low light, and curves, and effectively enhancing the environmental perception capability and overall driving safety of the autonomous driving system.

[0179] Based on the same inventive concept, the present application also provides an electronic device, which may be a terminal device such as a server, a desktop computing device or a mobile computing device (e.g., a laptop computing device, a handheld computing device, a tablet computer, a netbook, etc.). The device includes one or more processors and a memory, wherein the processor is used to execute a program to implement the method for controlling the lateral lighting angle of a vehicle headlamp according to an embodiment of the present invention; and the memory is used to store a computer program executable by the processor.

[0180] Based on the same inventive concept, the present application also provides a computer-readable storage medium, corresponding to the embodiment of the method for controlling the lateral illumination angle of a vehicle headlamp described above. The computer-readable storage medium stores a computer program, and when the program is executed by a processor, the steps of the method for controlling the lateral illumination angle of the vehicle headlamp recorded in any of the above embodiments are implemented.

[0181] The present application may be in the form of a computer program product implemented on one or more storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing program code. Computer-usable storage media include permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. The information may be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include but are 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 memory technologies, CD-ROM read-only optical discs, digital versatile discs (DVDs) or other optical storage, magnetic cassette tapes, magnetic disk storage or other magnetic storage devices, or any other non-transmission media that can be used to store information accessible by a computing device.

[0182] The above-described embodiments merely represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the inventive concept of the present invention, several modifications and improvements can still be made, and the present invention also intends to include these modifications and improvements.

Claims

1. A control method for the lateral illumination angle of a vehicle headlamp, characterized in that, It includes the following steps: S1: Obtain the current vehicle state information and the desired trajectory; wherein, the vehicle state information includes vehicle speed, vehicle heading angle, vehicle yaw rate, vehicle steering wheel angle, and vehicle position; the desired trajectory includes a sequence of desired trajectory points and path curvature within a future prediction time domain; S2: Use a vehicle path tracking steering model to perform state estimation on the current vehicle state information to obtain vehicle attitude information within a future time domain; S3: Solve and optimize a path tracking objective function based on the vehicle attitude information and the desired trajectory within a future time domain to obtain an optimal front wheel steering angle control quantity within a future time domain; S4: Solve and optimize the left and right lighting angle objective functions respectively based on the vehicle attitude information, the optimal front wheel steering angle control quantity, and the desired trajectory within a future time domain to obtain control quantities for the optimal left and right front headlights within a future time domain; S5: Perform signal conversion on the optimal front wheel steering angle control quantity and the control quantities for the optimal left and right front headlights at a first moment to obtain actual control signals for the steering angle and the front headlights, and send them to corresponding drive units respectively to complete the optimization of the optimal lateral lighting angle.

2. The control method for the lateral illumination angle of a vehicle headlamp according to claim 1, characterized in that, The specific differential equation structure of the vehicle path tracking steering model is represented as follows: wherein, represents the change rate of vehicle attitude information, and x(t) represents the vehicle attitude information at the t-th moment, that is, the vehicle state vector, which is specifically expressed as follows: where v y is the lateral velocity; r is the yaw rate; ψ L is the heading angle error; y L is the lateral displacement; δ represents the steering wheel angle, i.e., the front wheel angle; represents the steering wheel angular velocity; M d is the operating torque for the driver or the autonomous driving system; w(t) is the lateral disturbance input at the t-th moment; A is the state transition matrix, and its specific representation is as follows: Wherein, where v x is the forward speed; l s is the preview distance, which is used to represent the Euclidean distance between the vehicle's center of mass and the desired trajectory point; C f and C r are the cornering stiffnesses of the front and rear wheels respectively; m represents the vehicle mass; l f and l r are the distances from the vehicle's center of mass to the front and rear axles of the vehicle respectively; I z is the moment of inertia of the vehicle about the z-axis perpendicular to the ground; I S is the equivalent moment of inertia of the steering system; η t is the contact length between the tire and the ground; R S is the steering system gear ratio; B S is the steering wheel angle damping coefficient; M d represents the operating torque for the steering system; B is a control input gain matrix, and its specific representation is as follows: B w is the disturbance input gain matrix, and its specific representation is as follows: where l w represents the distance from the acting point of the lateral force to the vehicle's center of mass.

3. The control method for the lateral illumination angle of the vehicle headlamp according to claim 2, characterized in that, The specific structure of the path tracking objective function is represented as follows: where J track is the path tracking objective function; T represents the future prediction time domain considered under the current control period; w y is the weight coefficient of the lateral displacement error; e y (s|t k ) is the lateral displacement error corresponding to the desired trajectory point s, which is obtained by calculating through the vehicle steering kinematic error model; is the weight coefficient of the heading angle error; is the heading angle error corresponding to the desired trajectory point s, which is obtained by calculating through the vehicle steering kinematic error model; w δ is the weight coefficient for steering control; δ(s|t k ) is the steering wheel angle corresponding to the desired trajectory point s, that is, the control input; Wherein, the minimization solution expression for minimizing and solving the path tracking objective function is as follows: In the formula, represents the optimal front wheel steering angle control quantity corresponding to the t k th moment in the future time domain; argmin δ J track (t k ) is used to represent that under all potential front wheel steering angle control input sequences, the front wheel steering angle control quantity corresponding to the minimum value of the path tracking objective function J track (t k ) is obtained; Wherein, the differential equation of the vehicle steering kinematic error model is represented as follows: In the formula, is the path progress change rate; is the lateral error change rate; is the heading error change rate; ρ is the path curvature.

4. The control method for the lateral illumination angle of the vehicle headlamp according to claim 3, characterized in that, The specific expressions of the left lighting angle objective function and the right lighting angle objective function are as follows: In the formula, J L , J R are respectively the left lighting angle objective function and the right lighting angle objective function; w θL , w θR are respectively the weight coefficient of the left lighting error and the weight coefficient of the right lighting error; θ L (s|t k ) and θ R (s|t k ) are respectively the actual lighting angles of the left headlamp and the right headlamp, and are specifically obtained through iterative calculation by the angle adjustment change rate . The differential equation of the angle adjustment change rate of the left lighting angle is expressed as follows: where a L represents the state transition coefficient of the left headlight stepping motor; b L represents the control gain coefficient of the left headlight stepping motor; u L (s|t k ) is the control amount of the left headlight at the desired trajectory point s; The differential equation of the angular adjustment change rate of the right lighting angle is expressed as: Where, a R represents the state transition coefficient of the right headlight stepping motor; b R represents the control gain coefficient of the right headlight stepping motor; u R (s|t k ) is the control quantity of the right headlight at the desired trajectory point s; φ L (s|t k ), φ R (s|t k ) are the ideal illumination angles on the left and the ideal illumination angles on the right calculated according to the desired trajectory and the vehicle attitude information at the desired trajectory point s; Wherein, the minimization solution expressions for minimizing and solving the left and right lighting angle objective functions are as follows: In the formula, represents the control amount of the optimal left headlight corresponding to the t k th moment in the future time domain; is used to represent that under all potential control input sequences of the left headlight, the control amount of the left headlight corresponding to obtaining the minimum value of the objective function J E (t k ) is obtained, and this control amount is used as the optimized output for actual lighting control execution; Among them, the actual illumination angle θ of the left headlamp L (s|t0) and the actual illumination angle θ of the right headlamp R (s|t0) are calculated as the initial values as follows: By using the steering kinematic relationship of the vehicle to convert the corresponding optimal front wheel steering angle control quantity to obtain the current vehicle heading angle, and using it as the initial value of the actual lighting angles of the left and right front headlights, the specific representation of the steering kinematic relationship of the vehicle is as follows: In the formula, respectively represent the change rates of the x-axis coordinate and the y-axis coordinate in the global coordinate system of the vehicle's center of mass; represents the change rate of the vehicle's heading angle, and its specific representation is as follows: wherein, the vehicle yaw rate r is approximately equal to the vehicle heading angle change rate that is 5. A control device for the lateral illumination angle of a vehicle headlamp, characterized in that, It includes a vehicle state - path trajectory acquisition unit, a vehicle attitude estimation unit, a path tracking predictive control unit, a predictive control unit for the front headlights, and a control signal conversion unit; The vehicle state - path trajectory acquisition unit is used to obtain the current vehicle state information and the desired trajectory; wherein, the vehicle state information includes vehicle speed, vehicle heading angle, vehicle yaw rate, vehicle steering wheel angle, and vehicle position; the desired trajectory includes a sequence of desired trajectory points and path curvature within a future prediction time domain; The vehicle attitude estimation unit is used to perform state estimation on the current vehicle state information by using a vehicle path tracking steering model to obtain vehicle attitude information within a future time domain; The path tracking predictive control unit is used to solve and optimize a path tracking objective function based on the vehicle attitude information and the desired trajectory within a future time domain to obtain an optimal front wheel steering angle control quantity within a future time domain; The predictive control unit of the headlamp is configured to solve and optimize the left and right lighting angle objective functions respectively according to the vehicle attitude information, the optimal front wheel steering angle control quantity, and the desired trajectory within the future time domain, so as to obtain the control quantities of the optimal left and right headlamps within the future time domain; The control signal conversion unit is configured to perform signal conversion on the optimal front wheel steering angle control quantity and the control quantities of the optimal left and right headlamps at the first moment to obtain the actual control signals of the steering angle and the headlamps, and send them to the corresponding drive units respectively to complete the optimization of the optimal lateral lighting angle.

6. The control device for the lateral illumination angle of a vehicle headlamp according to claim 5, characterized in that, The specific differential equation structure of the vehicle path tracking steering model is represented as follows: In the formula, represents the change rate of vehicle attitude information, where x(t) represents the vehicle attitude information at the t-th moment, that is, the vehicle state vector, and is specifically expressed as follows: where v y is the lateral velocity; r is the yaw rate; ψ L is the heading angle error; y L is the lateral displacement; δ represents the steering wheel angle, i.e., the front wheel angle; represents the steering wheel angular velocity; M d is the operating torque for the driver or the autonomous driving system; w(t) is the lateral disturbance input at the t-th moment; A is the state transition matrix, and its specific representation is as follows: Wherein, where, v x is the forward speed; l s is the preview distance, which is used to represent the Euclidean distance between the vehicle's center of mass and the desired trajectory point; C f and C r are the cornering stiffnesses of the front and rear wheels respectively; m represents the vehicle mass; l f and l r are the distances from the vehicle's center of mass to the front and rear axles of the vehicle respectively; I z is the moment of inertia of the vehicle about the z-axis perpendicular to the ground; I S is the equivalent moment of inertia of the steering system; η t is the contact length between the tire and the ground; R S is the steering system gear ratio; B S is the steering wheel angle damping coefficient; M d represents the operating torque for the steering system; B is the control input gain matrix, and its specific representation is as follows: B w is the disturbance input gain matrix, and its specific representation is as follows: where l w represents the distance from the acting point of the lateral force to the vehicle's center of mass.

7. The control device for the lateral illumination angle of a vehicle headlamp according to claim 6, characterized in that, The specific structure of the path tracking objective function is represented as follows: where J track is the path-tracking objective function; T represents the future prediction time domain considered under the current control period; w y is the weight coefficient of the lateral displacement error; e y (s|t k ) is the lateral displacement error corresponding to the desired trajectory point s, which is obtained by calculating through the vehicle steering kinematic error model; is the weight coefficient of the heading angle error; is the heading angle error corresponding to the desired trajectory point s, which is obtained by calculating through the vehicle steering kinematic error model; w δ is the weight coefficient for steering control; δ(s|y k ) is the steering wheel angle corresponding to the desired trajectory point s, that is, the control input; Wherein, the minimization solution expression for minimizing and solving the path tracking objective function is as follows: In the formula, represents the optimal front wheel steering angle control quantity corresponding to the t k th moment in the future time domain; argmin δ J track (t k ) is used to represent that under all potential front wheel steering angle control input sequences, the front wheel steering angle control quantity corresponding to the minimum value of the path tracking objective function J track (t k ) is obtained; Wherein, the differential equation of the vehicle steering kinematic error model is represented as follows: In the formula, is the path progress change rate; is the lateral error change rate; is the heading error change rate; ρ is the path curvature.

8. The control device for the lateral illumination angle of a vehicle headlamp according to claim 7, characterized in that, The specific expressions of the left lighting angle objective function and the right lighting angle objective function are as follows: In the formula, J L , J R are respectively the left-side lighting angle objective function and the right-side lighting angle objective function; w θL , w θR are respectively the weight coefficients of the left-side lighting error and the right-side lighting error; θ L (s|t k ) and θ R (s|t k ) are respectively the actual lighting angles of the left headlamp and the right headlamp, which are specifically obtained through iterative calculation by the angle adjustment change rate . The differential equation of the angle adjustment change rate of the left-side lighting angle is expressed as follows: Where a L represents the state transition coefficient of the left headlight stepper motor; b L represents the control gain coefficient of the left headlight stepper motor; u L (s|t k ) is the control amount of the left headlight at the desired trajectory point s; The differential equation of the angular adjustment change rate of the right lighting angle is expressed as: Where, a R represents the state transition coefficient of the right headlight stepping motor; b R represents the control gain coefficient of the right headlight stepping motor; u R (s|t k ) is the control amount of the right headlight at the desired trajectory point s; φ L (s|t k ), φ R (s|t k ) are the ideal illumination angles on the left side and the ideal illumination angles on the right side calculated according to the desired trajectory and vehicle attitude information at the desired trajectory point s. Wherein, the minimization solution expressions for minimizing and solving the left and right lighting angle objective functions are as follows: In the formula, represents the control quantity of the optimal left headlamp corresponding to the t k th moment in the future time domain; is used to represent that, under all potential control input sequences of the left headlamp, the control quantity of the left headlamp corresponding to obtaining the minimum value of the objective function J R (t k ) is obtained, and this control quantity is used as the optimized output for actual lighting control execution; Among them, the actual illumination angle θ of the left headlight L (s|t0) and the actual illumination angle θ of the right headlight R (s|t0) are calculated and expressed as follows: By using the steering kinematic relationship of the vehicle to convert the corresponding optimal front wheel steering angle control quantity to obtain the current vehicle heading angle, and using it as the initial value of the actual lighting angles of the left and right headlamps, the specific representation of the steering kinematic relationship of the vehicle is as follows: wherein, respectively represent the change rates of the x-axis coordinate and the y-axis coordinate in the global coordinate system of the vehicle's center of mass; represents the change rate of the vehicle's heading angle, and its specific representation is as follows: wherein, the vehicle yaw rate r is approximately equal to the vehicle heading angle change rate i.e., 9. An electronic device, comprising: A memory, a processor, and a computer program stored on the memory and executable on the processor, wherein when the processor executes the computer program, the control method for the lateral lighting angle of the vehicle headlamp as described in any one of claims 1 to 4 is implemented.

10. A computer-readable storage medium storing computer-executable instructions, characterized in that, When the computer-executable instructions are executed by the processor, the control method for the lateral lighting angle of the vehicle headlamp as described in any one of claims 1 to 4 is implemented.

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