Vehicle control method, system, vehicle, and storage medium

Abstract

This application provides a vehicle control method, system, vehicle, and storage medium. The method includes: acquiring the vehicle's current driving speed and planned driving trajectory; determining the coordinates of a preview point based on the current driving speed and planned driving trajectory, wherein the preview point coordinates represent the vehicle's position at the next moment; determining a target yaw rate based on the vehicle's current pose information and the preview point coordinates; determining a target front wheel steering angle command based on the target yaw rate; and controlling the vehicle's driving trajectory based on the target front wheel steering angle command. This application solves the technical problem of low trajectory tracking accuracy in related technologies' autonomous driving systems.

Description

Technical Field

[0001] This application relates to the field of autonomous driving technology, and more specifically, to a vehicle control method, system, vehicle, and storage medium. Background Technology

[0002] Trajectory tracking technology in intelligent driving vehicles refers to the process by which the vehicle adjusts the wheel angles through a lateral control system to ensure that the vehicle's actual driving path conforms to the desired trajectory. Adopting trajectory tracking technology can improve driving safety, prevent lane departures or collisions, and enhance passenger comfort.

[0003] Existing trajectory tracking technologies, such as those based on modern control theory, can handle constraints and optimization objectives, but they suffer from low trajectory tracking accuracy.

[0004] There is currently no good solution to the above problems. Summary of the Invention

[0005] This application provides a vehicle control method, system, vehicle, and storage medium to at least solve the technical problem of low trajectory tracking accuracy in related technologies for autonomous driving systems.

[0006] According to one aspect of the embodiments of this application, a vehicle control method is provided, comprising: acquiring the current driving speed and planned driving trajectory of the vehicle; determining the coordinates of a preview point based on the current driving speed and planned driving trajectory, wherein the coordinates of the preview point are used to represent the position of the vehicle at the next moment; determining a target yaw rate based on the current pose information of the vehicle and the coordinates of the preview point; determining a target front wheel steering angle command based on the target yaw rate; and controlling the driving trajectory of the vehicle based on the target front wheel steering angle command.

[0007] Furthermore, the coordinates of the aiming point are determined based on the current driving speed and the planned driving trajectory, including: obtaining the preset aiming time; determining the aiming distance based on the preset aiming time and the current driving speed; and searching the planned driving trajectory based on the aiming distance to obtain the coordinates of the aiming point.

[0008] Furthermore, the target yaw rate is determined based on the vehicle's current pose information and the coordinates of the preview point, including: determining the path curvature and the rate of change of path curvature based on the current pose information and the coordinates of the preview point; and determining the target yaw rate based on the current driving speed, path curvature, and the rate of change of path curvature.

[0009] Further, determining the target yaw rate based on the current driving speed, path curvature, and path curvature change rate includes: determining an initial yaw rate based on the path curvature and path curvature change rate; determining the vehicle's lateral acceleration based on the current driving speed and initial yaw rate; determining an intermediate yaw rate based on the first preset comfort threshold in response to the lateral acceleration exceeding the first preset comfort threshold; determining the vehicle's lateral jerk based on the current driving speed and intermediate yaw rate; and smoothing the intermediate yaw rate to obtain the target yaw rate in response to the lateral jerk exceeding a second preset comfort threshold.

[0010] Further, the target front wheel steering angle command is determined based on the target yaw rate, including: determining the feedforward control quantity, feedback control quantity, and zero-bias compensation control quantity based on the target yaw rate; determining the initial front wheel steering angle command based on the feedforward control quantity, feedback control quantity, and zero-bias compensation control quantity; and obtaining the target front wheel steering angle command by constraining the output steering angle in the initial front wheel steering angle command.

[0011] Furthermore, the feedforward control quantity, feedback control quantity, and zero-bias compensation control quantity are determined based on the target yaw rate, including: determining the desired turning radius, yaw rate deviation, and zero-bias estimate based on the target yaw rate, wherein the yaw rate deviation is used to represent the difference between the target yaw rate and the actual yaw rate; determining the feedforward control quantity based on the desired turning radius; determining the feedback control quantity based on the yaw rate deviation; and determining the zero-bias compensation control quantity based on the zero-bias estimate.

[0012] Furthermore, by constraining the output angle in the initial front wheel steering angle command, a target front wheel steering angle command is obtained, including: constraining the output angle in the initial front wheel steering angle command based on a preset mechanical steering angle range to obtain a first front wheel steering angle command; determining the steering angle change rate based on the output angle in the first front wheel steering angle command and the output angle in the second front wheel steering angle command of the previous control cycle; and limiting the output angle in the first front wheel steering angle command in response to the steering angle change rate exceeding a preset response speed to obtain the target front wheel steering angle command.

[0013] According to another aspect of the embodiments of this application, a vehicle control system is also provided, applied to the vehicle control method in any of the above claims, comprising: a kinematic control module for generating a target yaw rate based on a planned driving trajectory and the current pose information of the vehicle; and a dynamic control module for generating a target front wheel steering angle based on the target yaw rate.

[0014] According to another aspect of the embodiments of this application, a vehicle control device is also provided, comprising: an acquisition module for acquiring the current driving speed and planned driving trajectory of the vehicle; a first determination module for determining the coordinates of a preview point based on the current driving speed and planned driving trajectory, wherein the coordinates of the preview point are used to represent the position of the vehicle at the next moment; a second determination module for determining a target yaw rate based on the current pose information of the vehicle and the coordinates of the preview point; a third determination module for determining a target front wheel steering angle command based on the target yaw rate; and a control module for controlling the driving trajectory of the vehicle based on the target front wheel steering angle command.

[0015] Furthermore, the first determining module is also used to obtain a preset aiming time; determine the aiming distance based on the preset aiming time and the current driving speed; and search the planned driving trajectory based on the aiming distance to obtain the coordinates of the aiming point.

[0016] Furthermore, the second determining module is also used to determine the path curvature and the rate of change of path curvature based on the current pose information and the coordinates of the pre-aiming point; and to determine the target yaw rate based on the current driving speed, path curvature and the rate of change of path curvature.

[0017] Furthermore, the second determining module is also used to determine the initial yaw rate based on the path curvature and the rate of change of path curvature; determine the lateral acceleration of the vehicle based on the current driving speed and the initial yaw rate; determine the intermediate yaw rate based on the first preset comfort threshold in response to the lateral acceleration exceeding the first preset comfort threshold; determine the lateral acceleration of the vehicle based on the current driving speed and the intermediate yaw rate; and smooth the intermediate yaw rate to obtain the target yaw rate in response to the lateral acceleration exceeding the second preset comfort threshold.

[0018] Furthermore, the third determining module is also used to determine the feedforward control quantity, feedback control quantity, and zero-bias compensation control quantity according to the target yaw rate; determine the initial front wheel steering angle command according to the feedforward control quantity, feedback control quantity, and zero-bias compensation control quantity; and obtain the target front wheel steering angle command by constraining the output steering angle in the initial front wheel steering angle command.

[0019] Furthermore, the third determining module is also used to determine the desired turning radius, yaw rate deviation, and zero bias estimate based on the target yaw rate, wherein the yaw rate deviation is used to represent the difference between the target yaw rate and the actual yaw rate; to determine the feedforward control quantity based on the desired turning radius; to determine the feedback control quantity based on the yaw rate deviation; and to determine the zero bias compensation control quantity based on the zero bias estimate.

[0020] Furthermore, the third determining module is also used to constrain the output angle in the initial front wheel angle command based on a preset mechanical angle range to obtain a first front wheel angle command; determine the angle change rate based on the output angle in the first front wheel angle command and the output angle in the second front wheel angle command of the previous control cycle; and in response to the angle change rate exceeding a preset response speed, perform amplitude limiting processing on the output angle in the first front wheel angle command to obtain a target front wheel angle command.

[0021] According to another aspect of the embodiments of this application, a vehicle is also provided, including: a memory storing an executable program; and a processor for running the executable program, wherein the executable program executes the vehicle control method described in any of the above embodiments when running on the processor.

[0022] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer-readable storage medium, and the computer program is configured to execute the vehicle control method described in any of the above when it is run on a computer or processor.

[0023] According to another aspect of the embodiments of this application, a computer program product is also provided, including a computer program that, when executed by a processor, implements the vehicle control methods in various embodiments of this application.

[0024] According to another aspect of the embodiments of this application, a computer program product is also provided, including a non-volatile computer-readable storage medium storing a computer program, which, when executed by a processor, implements the vehicle control method in various embodiments of this application.

[0025] According to another aspect of the embodiments of this application, a computer program is also provided, which, when executed by a processor, implements the vehicle control methods in the various embodiments of this application.

[0026] In this embodiment, the current driving speed and planned driving trajectory of the vehicle are first obtained. Then, the coordinates of the preview point are determined based on the current driving speed and planned driving trajectory. The coordinates of the preview point are used to represent the position of the vehicle at the next moment. Next, the target yaw rate is determined based on the current pose information of the vehicle and the coordinates of the preview point. The target front wheel steering command is determined based on the target yaw rate. Finally, the driving trajectory of the vehicle is controlled based on the target front wheel steering command. This achieves the goal of balancing the rationality of motion planning and the stability of dynamic execution, thereby improving the trajectory tracking accuracy of the autonomous driving system and solving the technical problem of low trajectory tracking accuracy in related technologies. Attached Figure Description

[0027] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0028] Figure 1 This is a flowchart of a vehicle control method according to an embodiment of this application;

[0029] Figure 2 This is a schematic diagram of an optional algorithm flow according to an embodiment of this application;

[0030] Figure 3 This is a schematic diagram of a vehicle control system according to an embodiment of this application;

[0031] Figure 4 This is a schematic diagram of an optional overall system architecture according to an embodiment of this application;

[0032] Figure 5 This is a schematic diagram of a vehicle control device according to an embodiment of this application. Detailed Implementation

[0033] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0034] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0035] According to an embodiment of this application, an embodiment of a vehicle control method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0036] This embodiment provides a vehicle control method. Figure 1 This is a flowchart of a vehicle control method according to an embodiment of this application, such as... Figure 1 As shown, the process includes the following steps:

[0037] Step S10: Obtain the vehicle's current speed and planned driving trajectory;

[0038] In this embodiment, the current driving speed refers to the real-time longitudinal speed of the vehicle, which is usually collected by the Controller Area Network (CAN) bus or a high-precision wheel speed sensor, and is measured in m / s or km / h, representing the instantaneous motion state of the vehicle in the driving direction.

[0039] The planned driving trajectory refers to the continuous spatial reference path output by the upper-level path planning module of the autonomous driving system. It is usually represented as a discrete point sequence, with each trajectory point containing lateral coordinates (x, y), heading angle (θ), curvature (κ), and relative time or arc length information. The planned driving trajectory is used to represent the ideal driving path that the vehicle should follow.

[0040] Obtaining the vehicle's current speed and planned trajectory can be understood as follows: The vehicle's longitudinal speed signal (v) is acquired in real time via the onboard CAN bus. This longitudinal speed signal v originates from wheel speed sensors or the powertrain control unit, representing the vehicle's instantaneous motion state. Simultaneously, structured trajectory data is received from the path planning module. This data is represented as a sequence of discrete trajectory points in either the Frenet or Cartesian coordinate system. Each trajectory point includes global position coordinates (x, y), heading angle (θ), and path curvature (κ), forming the planned trajectory for the vehicle's desired motion.

[0041] It can be seen that by collecting the vehicle's current speed and planned trajectory in real time, accurate motion status and reference benchmarks are provided for the subsequent control layer, ensuring the spatiotemporal consistency and dynamic response accuracy of trajectory tracking, effectively improving the system's ability to predict changes in path curvature, and enhancing the stability and robustness of trajectory tracking.

[0042] Step S12: Determine the coordinates of the aiming point based on the current driving speed and the planned driving trajectory. The coordinates of the aiming point are used to indicate the position of the vehicle at the next moment.

[0043] In this embodiment, the aiming point coordinates refer to the spatial position of a future reference point in the global coordinate system (or vehicle coordinate system) predicted forward along the arc length of the planned driving trajectory based on the current driving speed and aiming time. The aiming point coordinates are not the physical position of the vehicle, but rather represent the expected motion state point that the vehicle will tend to in the next control cycle, so as to achieve accurate tracking of the vehicle's dynamic trajectory.

[0044] Determining the aiming point coordinates based on the current driving speed and the planned driving trajectory can be understood as follows: Based on the vehicle's current longitudinal speed within the arc length parameterized representation of the planned driving trajectory, the aiming distance is calculated by integrating along the tangential direction of the trajectory, and then interpolating to obtain the three-dimensional state point at the corresponding arc length position on the trajectory; this is the aiming point coordinate. The aiming point coordinates serve as a spatiotemporal prediction reference for the vehicle's future instantaneous motion state, used to extract the local curvature change rate of the path, thereby achieving feedforward compensation for the dynamic delay of the steering actuator and improving the dynamic stability of trajectory tracking.

[0045] It can be seen that by dynamically calculating the coordinates of the aiming point based on the current driving speed and the planned driving trajectory, accurate spatiotemporal prediction of the vehicle's future motion state can be achieved, effectively compensating for the inherent delay of the steering actuator, improving the dynamic response capability of path tracking, thereby enhancing the system's adaptability to the rate of change of trajectory curvature, and improving ride comfort and trajectory tracking accuracy while ensuring control stability.

[0046] Step S14: Determine the target yaw rate based on the vehicle's current pose information and the coordinates of the pre-aiming point;

[0047] In this embodiment, the current pose information refers to the real-time state parameters of the vehicle in the global coordinate system or the vehicle body coordinate system, which are used to characterize the current spatial attitude and motion state of the vehicle.

[0048] The target yaw rate is obtained by the kinematic control layer based on the vehicle's current pose and the coordinates of the target aiming point. It is obtained through trajectory fitting and feedforward compensation of the rate of curvature change, and is used to characterize the instantaneous steering dynamic response required by the vehicle to accurately track the planned driving trajectory. It is the direct control input of the dynamic control layer.

[0049] Determining the target yaw rate based on the vehicle's current pose information and the coordinates of the preview point can be understood as follows: Based on the vehicle's current pose information and the coordinates of the preview point, boundary conditions for lateral position deviation and heading angle deviation are constructed in the vehicle coordinate system. A polynomial path fitting method is used to solve for the path curvature and rate of change of curvature at the preview point. Then, combined with the current vehicle speed, actuator delay feedforward compensation is completed, and a target yaw rate command that meets kinematic feasibility is output, thereby achieving high-precision dynamic trajectory tracking.

[0050] It can be seen that by fusing the vehicle's current pose information with the coordinate information of the pre-aiming point, the target yaw rate is generated analytically based on polynomial trajectory fitting, thereby achieving feedforward compensation for the delay of the steering actuator. This effectively improves the dynamic response accuracy of trajectory tracking, ensures smooth and controllable motion commands, balances computational efficiency and control stability, and provides highly reliable input for the subsequent dynamics layer.

[0051] Step S16: Determine the target front wheel steering angle command based on the target yaw rate;

[0052] In this embodiment, the target front wheel steering angle command is the final front wheel steering angle command output by the dynamics control layer based on the target yaw rate output by the kinematics layer. This command is achieved by fusing the steady-state feedforward model (including the real-time estimated understeer gradient), the feedback proportional-integral controller (PI) control term, and the steering system zero-bias compensation amount, and after physical constraint optimization. This command is used to drive the electric power steering system to achieve accurate tracking of the desired yaw dynamics.

[0053] Determining the target front wheel steering angle command based on the target yaw rate can be understood as follows: based on the target yaw rate output by the kinematic layer, the dynamics control layer constructs a feedforward-feedback-compensation joint control architecture. This architecture tracks the target yaw rate and outputs the target front wheel steering angle command, thereby stabilizing the vehicle's steering actuators.

[0054] It can be seen that by using feedforward-feedback-zero bias compensation coordinated control, the target yaw rate is accurately converted into the target front wheel steering angle command, which effectively suppresses model error, actuator zero bias and external interference, and significantly improves the dynamic accuracy and stability of steering response.

[0055] Step S18: Control the vehicle's trajectory based on the target front wheel steering angle command.

[0056] In this embodiment of the application, controlling the vehicle's driving trajectory based on the target front wheel steering angle command can be understood as applying the target front wheel steering angle command generated by the dynamics layer to the front wheels in real time through the vehicle steering actuator (such as an electric power steering system), driving the vehicle to actually yaw, so as to control the vehicle to drive according to the planned driving trajectory.

[0057] It can be seen that by driving the steering actuator in real time with the target front wheel steering angle command, the delay and nonlinearity of the steering actuator are effectively overcome, the real-time performance and consistency of trajectory tracking are improved, and the stability and ride comfort of the vehicle are enhanced under complex conditions such as high-speed curves and crosswind interference.

[0058] For example, this application proposes a vehicle kinematics and dynamics layered coordinated trajectory tracking control method. In the kinematics control layer, a target yaw rate is output based on the planned driving trajectory. In the dynamics control layer, a target front wheel steering angle is output based on this target yaw rate. Through this two-layer coordination, accurate, safe, and comfortable tracking of the target trajectory is achieved.

[0059] Specifically, the target yaw rate of the kinematic control layer is generated as follows: First, the trajectory point ahead is pre-aimed, and its coordinates and heading angle are obtained.

[0060] Next, in the vehicle coordinate system, starting from the current position (where both initial lateral and heading deviations are zero), and ending at the lateral position deviation y_t and heading deviation heading_t at the aiming point, a cubic polynomial curve is constructed with respect to the length of the trajectory. By solving this polynomial, an expression containing only the path curvature κ and its rate of change κ' can be directly obtained analytically.

[0061] Finally, based on the current travel speed v, and using the rate of curvature change, feedforward compensation is performed on the actuator delay τ (compensation amount: v). κ' The target yaw rate is calculated using τ. In the above process, the lateral acceleration and its rate of change (jerk) calculated based on the target yaw rate and vehicle speed are constrained within comfort limits to ensure the smoothness and safety of motion commands.

[0062] The dynamics control layer receives the target yaw rate γ_ref and achieves accurate tracking of γ_ref_smooth through a mechanism combining feedforward, feedback and zero bias compensation, and outputs the target front wheel steering angle δ_cmd.

[0063] Among them, the feedforward control δ_ff is calculated based on the vehicle steady-state yaw rate gain model that includes the real-time estimated understeering gradient K, and its core formula is: δ_ff=(L / R)+K a_y, where L is the wheelbase, R is the radius of curvature of the desired path, and a_y is the desired lateral acceleration. This model can quickly respond to changes in path curvature. Feedback control δ_fb employs a PI controller based on the deviation between the target and actual yaw rates to suppress model errors and external disturbances. Zero-bias compensation statically compensates for the total output steering angle using the real-time estimated zero-point offset δ_bias of the steering system. The final output target front wheel steering angle command δ_cmd = δ_ff + δ_fb + δ_bias.

[0064] Through the above steps, the current driving speed and planned driving trajectory of the vehicle are first obtained. Then, the coordinates of the preview point are determined based on the current driving speed and planned driving trajectory. The coordinates of the preview point are used to indicate the position of the vehicle at the next moment. Next, the target yaw rate is determined based on the current pose information of the vehicle and the coordinates of the preview point. The target front wheel steering command is then determined based on the target yaw rate. Finally, the driving trajectory of the vehicle is controlled based on the target front wheel steering command. This achieves the goal of balancing the rationality of motion planning and the stability of dynamic execution, thereby improving the trajectory tracking accuracy of the autonomous driving system and solving the technical problem of low trajectory tracking accuracy in related technologies.

[0065] Furthermore, in step S12, determining the coordinates of the pre-aiming point based on the current driving speed and the planned driving trajectory may include the following execution steps:

[0066] Step S121: Obtain the preset aiming time;

[0067] Step S122: Determine the aiming distance based on the preset aiming time and the current driving speed;

[0068] Step S123: Search the planned driving trajectory based on the pre-aiming distance to obtain the coordinates of the pre-aiming point.

[0069] In this embodiment, the preset aiming time is a fixed time parameter (e.g., 0.5~1.5 seconds) that is manually calibrated and used to characterize the control system's foresight regarding future paths.

[0070] The aiming distance is the spatial distance calculated based on the current vehicle and the aiming time. It represents the length of the path the vehicle will travel within that time. It is used to locate future aiming points on the planned driving trajectory to compensate for actuator delay and improve the smoothness and stability of trajectory tracking.

[0071] Obtaining the preset aiming time can be understood as reading a pre-calibrated fixed time value (such as 1.0 second) from the configuration parameters to balance response speed and stability, without changing with vehicle speed, and to ensure the consistency of control logic.

[0072] Determining the aiming distance based on the preset aiming time and the current driving speed can be understood as using the vehicle's real-time speed and aiming time to calculate the spatial distance, transforming the time-domain aiming into the spatial domain, so that the aiming point is always located a fixed time after the vehicle's future driving path, achieving dynamic aiming that is adaptive to vehicle speed.

[0073] Searching for the planned driving trajectory based on the pre-aiming distance to obtain the pre-aiming point coordinates can be understood as searching forward a point at a distance equal to the pre-aiming distance from the vehicle's current position along the arc length of the planned driving trajectory, and obtaining the lateral position and heading angle of the pre-aiming point in the vehicle coordinate system through interpolation to obtain the pre-aiming point coordinates.

[0074] It can be seen that the robustness of trajectory tracking is improved through a collaborative mechanism that presets the aiming time, dynamically calculates the aiming distance, and determines the coordinates of the aiming point. The preset aiming time, as a stable control parameter, avoids the problems of lag at high speeds and oversensitivity at low speeds inherent in traditional fixed-distance aiming. The aiming distance, generated based on vehicle speed adaptation, enables the system to dynamically match the driving state and effectively compensate for steering actuator delay. By locating the aiming point through arc length search, the system accurately obtains the path curvature change rate, providing accurate local geometric information to the kinematic layer, thereby enhancing tracking accuracy and ride comfort under curves and variable curvature conditions.

[0075] Further, in step S14, determining the target yaw rate based on the vehicle's current pose information and the coordinates of the preview point may include the following steps:

[0076] Step S141: Determine the path curvature and the rate of change of path curvature based on the current pose information and the coordinates of the preview point;

[0077] Step S142: Determine the target yaw rate based on the current driving speed, path curvature, and path curvature change rate.

[0078] In this embodiment, path curvature refers to the degree of local curvature of the planned driving trajectory at the aiming point. It is defined as the rate of change of the trajectory tangent direction with the arc length, reflecting the degree of turning at the aiming point. The greater the curvature, the sharper the vehicle turns.

[0079] The rate of change of path curvature is the derivative of curvature along the direction of travel. It characterizes the continuous trend of change in the curvature of the trajectory and reflects the smoothness or acceleration of the path.

[0080] Determining the path curvature and the rate of change of path curvature based on the current pose information and the coordinates of the preview point can be understood as constructing a cubic polynomial curve of the lateral deviation in the vehicle coordinate system, with the current vehicle position as the starting point and the preview point as the ending point, and then analytically solving for the coefficients through boundary conditions. At the preview point, the path curvature characterizes the instantaneous turning intensity at that point, and the rate of change of curvature describes the instantaneous trend of the path's curvature.

[0081] Determining the target yaw rate based on the current driving speed, path curvature, and path curvature change rate can be understood as follows: calculate the base yaw rate based on the current driving speed and path curvature, then perform feedforward compensation on the base yaw rate based on the path curvature change rate to effectively offset the steering system response lag, and finally output a smooth and safe target yaw rate after lateral acceleration constraints.

[0082] As can be seen, by fitting the pre-aiming segment trajectory using polynomials and analytically solving for the path curvature and its rate of change, numerical differential noise is avoided, achieving high-precision and robust geometric feature extraction. Feedforward compensation based on vehicle speed and the rate of curvature effectively offsets actuator delay, ultimately generating a smooth and safe target yaw rate. This improves cornering tracking accuracy and ride comfort, while also demonstrating high computational efficiency, meeting automotive-grade real-time control requirements and providing stable and reliable upper-level input for hierarchical control.

[0083] Further, in step S142, determining the target yaw rate based on the current driving speed, path curvature, and path curvature change rate may include the following execution steps:

[0084] The initial yaw rate is determined based on the path curvature and the rate of change of path curvature.

[0085] The lateral acceleration of the vehicle is determined based on the current driving speed and the initial yaw rate;

[0086] In response to the lateral acceleration exceeding a first preset comfort threshold, the intermediate yaw rate is determined based on the first preset comfort threshold;

[0087] The lateral acceleration of the vehicle is determined based on the current driving speed and the mid-range yaw rate;

[0088] In response to the lateral acceleration exceeding the second preset comfort threshold, the intermediate yaw rate is smoothed to obtain the target yaw rate.

[0089] In this embodiment, the initial yaw rate is obtained by feedforward compensation of the product of the path curvature and the current driving speed. It is used to represent the basic yaw rate necessary for the vehicle to travel along the pre-aiming point trajectory, reflecting the pure geometric tracking requirements.

[0090] Lateral acceleration is obtained by multiplying the current speed and the initial yaw rate. It represents the acceleration amplitude of the vehicle's lateral movement and is directly related to passenger comfort and tire lateral force requirements.

[0091] The first preset comfort threshold is the maximum allowable lateral acceleration limit of the system (e.g., ±3.0 m / s²), used to constrain the intensity of the lateral dynamic response and prevent passenger discomfort or tire skidding risk caused by sharp turns or high curvature paths.

[0092] The intermediate yaw rate is used to represent the correction value obtained by reverse limiting according to the first threshold, ensuring that the lateral acceleration is always within the comfortable range and maintaining the safety boundary of the control command.

[0093] Lateral acceleration is approximately calculated by multiplying the vehicle speed by the rate of change of yaw rate. It represents the time rate of change of lateral acceleration and is a key indicator for measuring ride comfort. If it is too high, it will cause passengers to feel abruptly.

[0094] The second preset comfort threshold is the maximum lateral acceleration limit allowed by the system (e.g., ±3.0 m / s³), used to constrain the abrupt change rate of lateral dynamics, ensure that acceleration changes are continuous and smooth, and avoid vehicle attitude oscillation or driving discomfort caused by command step changes.

[0095] Determining the initial yaw rate based on the path curvature and the rate of change of path curvature can be understood as follows: first, the base yaw rate is determined based on the product of the path curvature and the current driving speed; then, the actuator delay feedforward compensation is determined using the current driving speed, the rate of change of path curvature, and the calibrated actuator delay; finally, the base yaw rate is feedforward compensated using the actuator delay feedforward compensation to obtain the initial yaw rate.

[0096] Determining a vehicle's lateral acceleration based on its current speed and initial yaw rate can be understood as calculating the product of the current speed and initial yaw rate using dynamic relationships to obtain the vehicle's instantaneous lateral acceleration. This reflects the intensity of the vehicle's lateral dynamic response and is an important physical quantity for evaluating comfort and stability.

[0097] In response to the lateral acceleration exceeding the first preset comfort threshold, determining the intermediate yaw rate based on the first preset comfort threshold can be understood as follows: when the lateral acceleration exceeds the first preset comfort threshold, amplitude limiting is performed to correct the yaw rate to the intermediate yaw rate, thereby ensuring that the lateral acceleration does not exceed the preset comfort boundary and maintaining the controllability of the vehicle's dynamic response.

[0098] Determining the vehicle's lateral acceleration based on the current driving speed and the mid-range yaw rate can be understood as approximately calculating the vehicle's lateral acceleration based on the product of the current driving speed and the rate of change of the mid-range yaw rate, which is used to measure ride comfort.

[0099] In response to the lateral acceleration exceeding the second preset comfort threshold, the intermediate yaw rate is smoothed to obtain the target yaw rate. This can be understood as limiting the rate of change of the intermediate yaw rate when the lateral acceleration exceeds the second preset comfort threshold, thus obtaining the smoothed target yaw rate.

[0100] As can be seen, by analyzing the path curvature and rate of change of curvature, an initial yaw rate is constructed, enabling the generation of dynamic commands based on trajectory geometry. Combined with lateral acceleration constraints, this ensures that the vehicle's lateral dynamic response remains within the comfort and safety boundaries. Furthermore, the introduction of lateral acceleration limiting and smoothing mechanisms effectively suppresses vibrations and discomfort caused by abrupt command changes. These steps achieve a step-by-step optimization from the geometric path to comfort-controllable commands, improving the smoothness, safety, and riding experience of trajectory tracking.

[0101] Further, in step S16, determining the target front wheel steering angle command based on the target yaw rate may include the following execution steps:

[0102] Step S161: Determine the feedforward control quantity, feedback control quantity, and zero bias compensation control quantity according to the target yaw rate;

[0103] Step S162: Determine the initial front wheel steering angle command based on the feedforward control quantity, feedback control quantity, and zero bias compensation control quantity;

[0104] Step S163: By constraining the output angle in the initial front wheel steering angle command, the target front wheel steering angle command is obtained.

[0105] In this embodiment, the feedforward control quantity is a steering angle compensation component calculated based on the vehicle steady-state steering model. It is used to feedforward compensate for the steady-state steering angle requirements caused by path curvature and dynamic characteristics, thereby improving the tracking response speed and accuracy.

[0106] The feedback control quantity is a correction quantity generated by a PI controller from the deviation between the target yaw rate and the measured yaw rate. It is used to suppress steady-state errors and dynamic deviations caused by model uncertainties, external disturbances (such as crosswinds and slopes), and time-varying parameters, thereby enhancing the robustness of the system.

[0107] The zero-bias compensation control quantity is the static zero-point offset of the steering system output by the online estimation module. It is used to offset mechanical structure wear, sensor zero drift and actuator nonlinear zero-position error, and ensure that the steering command has no lag or deviation under stationary or low-speed conditions.

[0108] The initial front wheel steering angle command is a command obtained by linearly superimposing the feedforward control quantity, the feedback control quantity, and the zero bias compensation control quantity. It is the theoretical output of the controller and has not yet taken into account the physical limitations of the actuator.

[0109] The output steering angle refers to the steering angle magnitude to be implemented in the initial front wheel steering angle command.

[0110] Determining the feedforward control, feedback control, and zero-bias compensation control quantities based on the target yaw rate can be understood as follows: The feedforward control quantity is calculated based on the vehicle's steady-state steering dynamics model, determined by the target yaw rate and the current driving speed, and is used to compensate for the steady-state steering angle requirements caused by path geometry and vehicle dynamics characteristics. The feedback control quantity is generated by calculating the deviation between the target yaw rate and the actual yaw rate and using a PI controller to suppress tracking errors caused by external disturbances and unmodeled dynamics. Based on the target yaw rate, the zero-bias compensation control quantity is received from the steering system's online zero-bias estimation module to eliminate actuator nonlinear zero-position errors.

[0111] Determining the initial front wheel steering angle command based on the feedforward control quantity, feedback control quantity, and zero bias compensation control quantity can be understood as linearly superimposing the feedforward control quantity, feedback control quantity, and zero bias compensation control quantity to obtain the initial front wheel steering angle command. The initial front wheel steering angle command is the result of optimal control law synthesis without considering physical execution constraints, and it represents the complete steering angle command of the controller under ideal operating conditions.

[0112] By constraining the output angle in the initial front wheel steering angle command, the resulting target front wheel steering angle command can be understood as applying two physical constraints to the output angle of the initial command: amplitude limiting to ensure the output angle does not exceed the mechanical limits of the steering system (e.g., ±35°), and rate of change limiting to constrain the time derivative of the output angle to not exceed the maximum response rate of the steering actuator (e.g., ±30° / s), thus eliminating shocks and vibrations caused by sudden command changes. The constrained target front wheel steering angle command satisfies the actuator's dynamic characteristics, ensuring the safety, executability, and smoothness of the control command.

[0113] It can be seen that by using the three-channel coordinated control of feedforward, feedback and zero bias compensation, after obtaining the initial steering angle command, the output steering angle is strictly limited to the physical capability range of the actuator through the dual constraint processing of amplitude and rate of change. This improves the smoothness and executability of the target front wheel steering angle command, and achieves high-precision and low-jitter automotive-grade real-time steering control, providing reliable dynamic execution guarantee for the autonomous driving system.

[0114] Further, in step S161, determining the feedforward control quantity, feedback control quantity, and zero-bias compensation control quantity based on the target yaw rate may include the following execution steps:

[0115] The desired turning radius, yaw rate deviation, and zero bias estimate are determined based on the target yaw rate. The yaw rate deviation is used to represent the difference between the target yaw rate and the actual yaw rate.

[0116] Determine the feedforward control quantity based on the desired turning radius;

[0117] The feedback control quantity is determined based on the yaw rate deviation;

[0118] Determine the zero bias compensation control quantity based on the zero bias estimate.

[0119] In this embodiment, the desired turning radius is the theoretical turning radius calculated from the target yaw rate and the current vehicle speed through the kinematic relationship. It is used to characterize the desired steering geometry that the vehicle needs to achieve in order to track the planned driving trajectory and is a key input parameter in the feedforward control model.

[0120] Yaw rate deviation is the error between the target yaw rate and the actual measured yaw rate of the vehicle. It is used to quantify the tracking error at the dynamics execution level and serves as the input signal for the feedback controller.

[0121] The zero-bias estimate is the static zero-point offset of the steering mechanism, which is identified in real time by an online adaptive estimation algorithm (such as recursive least squares or sliding mode observer). It reflects the inherent deviation of the system caused by mechanical wear, sensor drift or actuator nonlinearity and is used for static compensation to ensure zero-error alignment of the steering angle command under zero speed or low speed conditions.

[0122] Determining the desired turning radius, yaw rate deviation, and zero-bias estimate based on the target yaw rate can be understood as follows: the desired turning radius is obtained through analytical calculation of the current vehicle speed and the target yaw rate using kinematic relationships. The yaw rate deviation is determined based on the target yaw rate and the actual yaw rate. At the target yaw rate, an online parameter identification module (such as an adaptive observer) continuously estimates the static offset of the steering system caused by mechanical wear, zero-point drift, or nonlinear hysteresis, thereby determining the zero-bias estimate.

[0123] Determining the feedforward control quantity based on the desired turning radius can be understood as calculating the desired turning radius based on the vehicle's steady-state steering model to obtain the feedforward control quantity, thereby achieving fast open-loop response and significantly reducing dynamic delay.

[0124] Determining the feedback control quantity based on the yaw rate deviation can be understood as using a proportional-integral controller to analyze the yaw rate deviation and generate a feedback control quantity, thereby eliminating model uncertainties, external disturbances (such as crosswinds and side slopes), and steady-state errors caused by time-varying parameters, and enhancing the robustness and asymptotic stability of the closed-loop system.

[0125] Determining the zero-bias compensation control quantity based on the zero-bias estimate can be understood as directly superimposing the real-time identified zero-bias estimate into the control command as a static compensation term to offset the inherent zero-point offset of the steering system, ensuring that the actual front wheel steering angle is aligned with the control command under zero-speed, low-speed, or steady-state conditions, thereby improving the control consistency and safety of the system under all operating conditions.

[0126] As can be seen, precise feedforward compensation is achieved by using the expected turning radius, which improves the path tracking response speed. PI feedback is constructed using the yaw rate deviation, which effectively suppresses interference and model errors. Combined with zero-bias compensation based on online estimation, static deviations of the steering system are eliminated, thereby improving safety and comfort and meeting the real-time control requirements of automotive-grade systems.

[0127] Further, in step S163, by constraining the output angle in the initial front wheel steering angle command, the target front wheel steering angle command is obtained, which may include the following execution steps:

[0128] The output angle in the initial front wheel angle command is constrained based on the preset mechanical angle range to obtain the first front wheel angle command.

[0129] The rate of change of steering angle is determined based on the output steering angle in the first front wheel steering angle command and the output steering angle in the second front wheel steering angle command of the previous control cycle;

[0130] In response to the steering angle change rate exceeding the preset response speed, the output steering angle in the first front wheel steering angle command is limited to obtain the target front wheel steering angle command.

[0131] In this embodiment, the preset mechanical angle range refers to the maximum physical angle limit allowed by the vehicle steering actuator (such as a steering motor or rack), which is usually ±30° to ±35°. It is used to prevent mechanical overload or interference and is a hard constraint boundary to ensure the safe operation of the actuator.

[0132] The first front wheel steering angle command refers to the initial steering angle command generated after the mechanical steering angle limit is met. That is, the output after the amplitude of the initial front wheel steering angle command is limited to avoid mechanical over-limit, but the smoothness of dynamic response has not yet been considered.

[0133] The steering angle change rate refers to the difference between the first front wheel steering angle command in the current control cycle and the command in the previous cycle, divided by the control cycle time. It characterizes the steepness of the instantaneous change in steering command and is used to measure steering impact and comfort.

[0134] The preset response speed is the maximum angular velocity threshold that the steering actuator can safely and smoothly track, usually 20° to 30° / s. It is calibrated by the actuator motor bandwidth and mechanical inertia to avoid vibration, overcurrent or response lag caused by sudden changes in commands.

[0135] The first front wheel angle command is obtained by constraining the output angle in the initial front wheel angle command based on the preset mechanical angle range. This can be understood as constraining the output angle in the initial front wheel angle command by a nonlinear saturation function to generate a first front wheel angle command that satisfies the mechanical safety boundary of the actuator, ensuring that the command is within the physical executable domain.

[0136] The rate of change of steering angle, determined by the output steering angle in the first front wheel steering angle command and the output steering angle in the second front wheel steering angle command of the previous control cycle, can be understood as follows: the rate of change of steering angle is obtained by dividing the difference between the output steering angle in the current first front wheel steering angle command and the output steering angle in the previous control cycle by the control cycle. This rate of change of steering angle is used to reflect the instantaneous slope of the steering command.

[0137] In response to the rate of change of steering angle exceeding the preset response speed, the output steering angle in the first front wheel steering angle command is limited to obtain the target front wheel steering angle command. This can be understood as follows: when the rate of change of steering angle exceeds the preset response speed, a first-order low-pass or gradient limiting algorithm is used to constrain the slope of the output steering angle in the first front wheel steering angle command to generate a smooth target front wheel steering angle command, thereby ensuring the smoothness of steering execution and passenger comfort.

[0138] As can be seen, by pre-setting the mechanical angle range, the amplitude of the initial front wheel steering angle command is limited to ensure that the output is always within the physical safety boundary of the steering actuator, avoiding mechanical overload and structural damage. Then, the rate of change of steering angle is calculated based on adjacent cycle commands to accurately quantify the intensity of steering dynamics. When the rate of change exceeds the preset response speed, slope limiting processing is implemented to improve the smoothness and continuity of steering commands while ensuring the reliability of the actuator, and reducing body roll impact and passenger discomfort.

[0139] Figure 2 This is a schematic diagram of an optional algorithm flow according to an embodiment of this application, such as... Figure 2 As shown, based on the current driving speed v and the preset fixed lookahead time T_lookahead (e.g., 0.5s to 1.5s), the lookahead distance L_p = v is calculated. T_lookahead. Find the point on the planned trajectory that is closest to the vehicle's current position, and trace back the aiming distance L_p to determine the aiming point P_t.

[0140] Obtain the lateral coordinate y_t (lateral position deviation) of P_t in the vehicle coordinate system and the difference between its heading angle and the current vehicle heading angle, heading_t (heading angle deviation).

[0141] In the vehicle coordinate system, assuming the path deviation from the current point (s=0, e=0, e'=0) to the aiming point (s=L_p, e=y_t, e'=tan(heading_t)≈heading_t) can be expressed by a cubic polynomial e(s)=a0+a1 about the arc length s. s+a2 s^2+a3 The coefficients can be analytically solved by substituting the boundary conditions into the s^3 description.

[0142] At the pre-aimed point P_t (s=L_p), calculate the path curvature κ_t=2. a2+6 a3 L_p, rate of change of curvature κ'_t=6 a3.

[0143] Calculate the base target value: γ_ref_base=v κ_t.

[0144] Perform actuator delay feedforward compensation: γ_ref_ff_comp=v κ'_t τ (τ is the calibrated actuator delay).

[0145] The initial yaw rate is obtained as: γ_ref_temp = γ_ref_base + γ_ref_ff_comp.

[0146] Calculate the corresponding lateral acceleration a_y=v γ_ref_temp. If a_y exceeds the preset comfort threshold (e.g., ±3.0m / s²), then the limited γ_ref_limit is calculated by recalculating after the threshold is applied; otherwise, γ_ref_limit = γ_ref_temp.

[0147] Based on the constrained γ_ref_limit described above, its rate of change Δγ / Δt is calculated in conjunction with the current control cycle. This rate of change is multiplied by the vehicle speed (i.e., v). (Δγ / Δt) is approximately the lateral jerk. If this calculated value exceeds the preset comfort jerk threshold (e.g., ±3.0 m / s³), the rate of change of γ_ref_limit needs to be limited to obtain a smoother final target yaw rate γ_ref_smooth.

[0148] The final target yaw rate γ_ref_smooth, after the above double constraint processing, is output to the dynamics control layer.

[0149] The dynamic control layer adopts a structure combining feedforward, feedback, and zero-bias compensation, and is implemented as follows:

[0150] Receive γ_ref_smooth and the current driving speed v from the kinematics control layer.

[0151] First, the desired turning radius is calculated based on R_ref = v / γ_ref_smooth. The feedforward steering angle δ_ff is calculated using a vehicle steady-state steering model that includes the real-time understeer gradient K: δ_ff = (L / R_ref) + K (v γ_ref_smooth / g (g is the acceleration due to gravity).

[0152] The key parameter K is provided in real time by an independent online understeering gradient estimation module, enabling the model to adapt to changes in vehicle handling characteristics.

[0153] Calculate the deviation e_γ between the target yaw rate γ_ref_smooth and the actual yaw rate γ, and generate a feedback correction amount δ_fb=Kp through a proportional-integral controller. e_γ+Ki e_γdt. Kp and Ki are calibrable parameters, and the integral term is used to eliminate steady-state error.

[0154] The system receives the zero-bias estimate δ_bias from the online zero-bias estimation module of the steering system, which is used to offset the static zero-point error of the steering system.

[0155] Summing the above feedforward control, feedback control, and zero bias compensation control, we obtain the initial front wheel steering angle command: δ_cmd_temp = δ_ff + δ_fb + δ_bias.

[0156] To ensure the feasibility and smoothness of the instructions, δ_cmd_temp is subject to two-step constraint processing:

[0157] Steering angle amplitude constraint: Limit δ_cmd_temp to the maximum allowable mechanical steering angle range of the steering system (e.g., ±35 degrees) to obtain δ_cmd_clamped.

[0158] Steering angle change rate constraint: Calculate the rate of change of δ_cmd_clamped relative to the output steering angle of the previous control cycle. If the rate of change exceeds the maximum allowable response speed of the steering motor (e.g., ±30 degrees / second), limit it to ensure smooth change of steering angle command and avoid shock.

[0159] The final target front wheel steering angle command δ_cmd, after physical constraints, is sent to the underlying controller of the steering actuator.

[0160] This embodiment provides a vehicle control system applied to any of the vehicle control methods described above. Figure 3 This is a schematic diagram of a vehicle control system according to an embodiment of this application, such as... Figure 3 As shown, the vehicle control system 300 includes:

[0161] The kinematic control module 301 is used to generate the target yaw rate based on the planned driving trajectory and the vehicle's current pose information;

[0162] The dynamics control module 302 is used to generate the target front wheel steering angle based on the target yaw rate.

[0163] In this embodiment, the kinematic control module 301 is an upper-level planning controller for trajectory tracking. Based on the relative deviation between the vehicle's current pose (position, heading) and the planned driving trajectory, it selects a pre-aiming point, fits the path deviation using a cubic polynomial, analyzes the curvature and rate of change of curvature, and combines the vehicle speed feedforward to compensate for the actuator delay. Finally, it outputs a target yaw rate that meets comfort constraints (lateral acceleration and jerk limits), thereby achieving coordinated optimization of path rationality and motion smoothness.

[0164] The dynamics control module 302 is an execution layer controller that receives the target yaw rate. By integrating feedforward control based on the vehicle steady-state model, PI feedback control, and online estimation of steering zero bias compensation, it accurately tracks the target yaw rate and outputs the target front wheel steering angle command after physical amplitude limiting, thereby achieving high-precision, robust, and low-latency closed-loop control of the vehicle's actual dynamic behavior.

[0165] It can be seen that the kinematic control module 301 and the dynamic control module 302 form a hierarchical coordination architecture for motion planning and dynamic execution, taking into account both computational efficiency and control performance.

[0166] Figure 4 This is a schematic diagram of an optional overall system architecture according to an embodiment of this application, such as... Figure 4 As shown, the overall system architecture includes: an input layer, an on-board control unit, and an output execution layer.

[0167] The input layer includes a vehicle sensor network and a path planning module. The onboard control unit includes a kinematics control layer, an understeer gradient estimation module, a steering angle zero-bias estimation module, and a dynamics control layer. The output execution layer includes the steering actuator.

[0168] The kinematic control layer receives the planned driving trajectory from the path planning module and outputs the target yaw rate. The dynamic control layer receives the real-time understeer gradient from the understeer gradient estimation module, the real-time steering angle zero bias from the steering angle zero bias estimation module, the real-time vehicle state from the vehicle sensor network, and the target yaw rate, and outputs the target front wheel steering angle. The steering actuator receives the target front wheel steering angle to control the vehicle's movement.

[0169] The kinematic control layer uses analytical cubic polynomial solutions, while the dynamics layer employs an efficient feedforward-feedback-compensation structure, avoiding complex online optimization solutions. The overall computational load of the algorithm is low, making it easy to run in real time on mainstream automotive-grade chips and meeting mass production requirements.

[0170] By introducing an independent real-time parameter estimation module (understeering gradient K, steering bias δ_bias), the control system can automatically adapt to changes in vehicle load, tire condition, etc.

[0171] By compensating for actuator delays with feedforward and suppressing unknown disturbances with feedback, the system exhibits excellent robustness to both time-varying internal parameters and external disturbances.

[0172] Lateral acceleration and jerk constraints in the kinematic control layer ensure ride comfort. Precise tracking in the dynamic control layer ensures path tracking accuracy.

[0173] The hierarchical coordination mechanism fundamentally balances the rationality of motion planning with the stability of dynamic execution, thereby enabling the simultaneous achievement of control objectives such as high-precision tracking, high safety, and high comfort under complex and diverse working conditions.

[0174] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of the relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and corresponding operation entry points are provided for users to choose to authorize or refuse.

[0175] According to an embodiment of this application, a vehicle control device is provided. It should be noted that the device can be used to execute the above-described vehicle control method.

[0176] Figure 5 This is a schematic diagram of a vehicle control device according to an embodiment of this application, such as... Figure 5 As shown, the vehicle control device 500 includes: an acquisition module 501 for acquiring the vehicle's current driving speed and planned driving trajectory; a first determination module 502 for determining the coordinates of a preview point based on the current driving speed and planned driving trajectory, wherein the preview point coordinates represent the vehicle's position at the next moment; a second determination module 503 for determining the target yaw rate based on the vehicle's current pose information and the preview point coordinates; a third determination module 504 for determining the target front wheel steering angle command based on the target yaw rate; and a control module 505 for controlling the vehicle's driving trajectory based on the target front wheel steering angle command.

[0177] Furthermore, the first determining module 502 is also used to obtain a preset aiming time; determine the aiming distance based on the preset aiming time and the current driving speed; and search the planned driving trajectory based on the aiming distance to obtain the coordinates of the aiming point.

[0178] Furthermore, the second determining module 503 is also used to determine the path curvature and the rate of change of path curvature based on the current pose information and the coordinates of the aiming point; and to determine the target yaw rate based on the current driving speed, path curvature and the rate of change of path curvature.

[0179] Furthermore, the second determining module 503 is also configured to determine the initial yaw rate based on the path curvature and the rate of change of path curvature; determine the lateral acceleration of the vehicle based on the current driving speed and the initial yaw rate; determine the intermediate yaw rate based on the first preset comfort threshold in response to the lateral acceleration exceeding the first preset comfort threshold; determine the lateral acceleration of the vehicle based on the current driving speed and the intermediate yaw rate; and smooth the intermediate yaw rate to obtain the target yaw rate in response to the lateral acceleration exceeding the second preset comfort threshold.

[0180] Furthermore, the third determining module 504 is also used to determine the feedforward control quantity, the feedback control quantity, and the zero-bias compensation control quantity according to the target yaw rate; determine the initial front wheel steering angle command according to the feedforward control quantity, the feedback control quantity, and the zero-bias compensation control quantity; and obtain the target front wheel steering angle command by constraining the output steering angle in the initial front wheel steering angle command.

[0181] Furthermore, the third determining module 504 is also used to determine the desired turning radius, yaw rate deviation, and zero bias estimate based on the target yaw rate, wherein the yaw rate deviation is used to represent the difference between the target yaw rate and the actual yaw rate; to determine the feedforward control quantity based on the desired turning radius; to determine the feedback control quantity based on the yaw rate deviation; and to determine the zero bias compensation control quantity based on the zero bias estimate.

[0182] Furthermore, the third determining module 504 is also used to constrain the output angle in the initial front wheel angle command based on a preset mechanical angle range to obtain a first front wheel angle command; determine the angle change rate based on the output angle in the first front wheel angle command and the output angle in the second front wheel angle command of the previous control cycle; and in response to the angle change rate exceeding a preset response speed, perform amplitude limiting processing on the output angle in the first front wheel angle command to obtain a target front wheel angle command.

[0183] According to another aspect of the embodiments of this application, a vehicle is also provided, including: a memory storing an executable program; and a processor for running the executable program, wherein the executable program executes the vehicle control method described in any of the above embodiments when running on the processor.

[0184] Optionally, in this embodiment, the processor in the vehicle can be configured to run a computer program to perform the following steps:

[0185] Step S10: Obtain the vehicle's current speed and planned driving trajectory;

[0186] Step S12: Determine the coordinates of the aiming point based on the current driving speed and the planned driving trajectory. The coordinates of the aiming point are used to indicate the position of the vehicle at the next moment.

[0187] Step S14: Determine the target yaw rate based on the vehicle's current pose information and the coordinates of the pre-aiming point;

[0188] Step S16: Determine the target front wheel steering angle command based on the target yaw rate;

[0189] Step S18: Control the vehicle's trajectory based on the target front wheel steering angle command.

[0190] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer-readable storage medium, and the computer program is configured to execute the vehicle control method described in any of the above when it is run on a computer or processor.

[0191] Optionally, in this embodiment, the computer-readable storage medium may be configured to store a computer program for performing the following steps:

[0192] Step S10: Obtain the vehicle's current speed and planned driving trajectory;

[0193] Step S12: Determine the coordinates of the aiming point based on the current driving speed and the planned driving trajectory. The coordinates of the aiming point are used to indicate the position of the vehicle at the next moment.

[0194] Step S14: Determine the target yaw rate based on the vehicle's current pose information and the coordinates of the pre-aiming point;

[0195] Step S16: Determine the target front wheel steering angle command based on the target yaw rate;

[0196] Step S18: Control the vehicle's trajectory based on the target front wheel steering angle command.

[0197] According to another aspect of the embodiments of this application, a computer program product is also provided, including a computer program that, when executed by a processor, implements the vehicle control methods in various embodiments of this application.

[0198] Optionally, in this embodiment, the computer program in the above-described computer program product can be configured to perform the following steps when executed by a processor:

[0199] Step S10: Obtain the vehicle's current speed and planned driving trajectory;

[0200] Step S12: Determine the coordinates of the aiming point based on the current driving speed and the planned driving trajectory. The coordinates of the aiming point are used to indicate the position of the vehicle at the next moment.

[0201] Step S14: Determine the target yaw rate based on the vehicle's current pose information and the coordinates of the pre-aiming point;

[0202] Step S16: Determine the target front wheel steering angle command based on the target yaw rate;

[0203] Step S18: Control the vehicle's trajectory based on the target front wheel steering angle command.

[0204] According to another aspect of the embodiments of this application, a computer program product is also provided, including a non-volatile computer-readable storage medium storing a computer program, which, when executed by a processor, implements the vehicle control method in various embodiments of this application.

[0205] Optionally, in this embodiment, the computer program in the above-described computer program product can be configured to perform the following steps when executed by a processor:

[0206] Step S10: Obtain the vehicle's current speed and planned driving trajectory;

[0207] Step S12: Determine the coordinates of the aiming point based on the current driving speed and the planned driving trajectory. The coordinates of the aiming point are used to indicate the position of the vehicle at the next moment.

[0208] Step S14: Determine the target yaw rate based on the vehicle's current pose information and the coordinates of the pre-aiming point;

[0209] Step S16: Determine the target front wheel steering angle command based on the target yaw rate;

[0210] Step S18: Control the vehicle's trajectory based on the target front wheel steering angle command.

[0211] According to another aspect of the embodiments of this application, a computer program is also provided, which, when executed by a processor, implements the vehicle control methods in the various embodiments of this application.

[0212] Optionally, in this embodiment, the computer program described above can be configured to perform the following steps when executed by the processor:

[0213] Step S10: Obtain the vehicle's current speed and planned driving trajectory;

[0214] Step S12: Determine the coordinates of the aiming point based on the current driving speed and the planned driving trajectory. The coordinates of the aiming point are used to indicate the position of the vehicle at the next moment.

[0215] Step S14: Determine the target yaw rate based on the vehicle's current pose information and the coordinates of the pre-aiming point;

[0216] Step S16: Determine the target front wheel steering angle command based on the target yaw rate;

[0217] Step S18: Control the vehicle's trajectory based on the target front wheel steering angle command.

[0218] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0219] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0220] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0221] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0222] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard drive, magnetic disk, or optical disk.

[0223] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A vehicle control method, characterized in that, include: Obtain the vehicle's current speed and planned driving trajectory; The coordinates of the aiming point are determined based on the current driving speed and the planned driving trajectory, wherein the coordinates of the aiming point are used to indicate the position of the vehicle at the next moment; The target yaw rate is determined based on the vehicle's current pose information and the coordinates of the pre-aiming point; The target front wheel steering angle command is determined based on the target yaw rate. The vehicle's trajectory is controlled based on the target front wheel steering angle command.

2. The method according to claim 1, characterized in that, Determining the coordinates of the aiming point based on the current driving speed and the planned driving trajectory includes: Obtain the preset aiming time; The aiming distance is determined based on the preset aiming time and the current driving speed; The planned driving trajectory is searched based on the pre-aiming distance to obtain the coordinates of the pre-aiming point.

3. The method according to claim 1, characterized in that, Determining the target yaw rate based on the vehicle's current pose information and the coordinates of the pre-aiming point includes: The path curvature and the rate of change of path curvature are determined based on the current pose information and the coordinates of the pre-aiming point; The target yaw rate is determined based on the current driving speed, the path curvature, and the rate of change of the path curvature.

4. The method according to claim 3, characterized in that, Determining the target yaw rate based on the current driving speed, the path curvature, and the rate of change of path curvature includes: The initial yaw rate is determined based on the path curvature and the rate of change of the path curvature; The lateral acceleration of the vehicle is determined based on the current driving speed and the initial yaw rate; In response to the lateral acceleration exceeding a first preset comfort threshold, the intermediate yaw rate is determined based on the first preset comfort threshold; The lateral acceleration of the vehicle is determined based on the current driving speed and the intermediate yaw rate; In response to the lateral acceleration exceeding a second preset comfort threshold, the intermediate yaw rate is smoothed to obtain the target yaw rate.

5. The method according to claim 1, characterized in that, The command to determine the target front wheel steering angle based on the target yaw rate includes: The feedforward control quantity, feedback control quantity, and zero bias compensation control quantity are determined based on the target yaw rate. The initial front wheel steering angle command is determined based on the feedforward control quantity, the feedback control quantity, and the zero-bias compensation control quantity; The target front wheel steering angle command is obtained by constraining the output steering angle in the initial front wheel steering angle command.

6. The method according to claim 5, characterized in that, The step of determining the feedforward control quantity, feedback control quantity, and zero-bias compensation control quantity based on the target yaw rate includes: The desired turning radius, yaw rate deviation, and zero bias estimate are determined based on the target yaw rate, wherein the yaw rate deviation is used to represent the difference between the target yaw rate and the actual yaw rate. The feedforward control quantity is determined based on the desired turning radius; The feedback control quantity is determined based on the yaw rate deviation. The zero-bias compensation control quantity is determined based on the zero-bias estimate.

7. The method according to claim 5, characterized in that, The step of constraining the output angle in the initial front wheel steering angle command to obtain the target front wheel steering angle command includes: The output angle in the initial front wheel angle command is constrained based on a preset mechanical angle range to obtain the first front wheel angle command. The rate of change of steering angle is determined based on the output steering angle in the first front wheel steering angle command and the output steering angle in the second front wheel steering angle command of the previous control cycle; In response to the steering angle change rate exceeding a preset response speed, the output steering angle in the first front wheel steering angle command is limited to obtain the target front wheel steering angle command.

8. A vehicle control system, applied to the vehicle control method according to any one of claims 1 to 7, characterized in that, include: The kinematic control module is used to generate the target yaw rate based on the planned driving trajectory and the vehicle's current pose information; The dynamics control module is used to generate the target front wheel steering angle based on the target yaw rate.

9. A vehicle, characterized in that, include: Memory, which stores executable programs; A processor for running the executable program, wherein the executable program, when run on the processor, performs the vehicle control method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, wherein the computer program is configured to execute the vehicle control method according to any one of claims 1 to 7 when run on a computer or processor.

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