Method for determining zero deflection angle of steering wheel and vehicle control method and device

Abstract

The invention provides a method for determining the zero deflection angle of a steering wheel and a vehicle control method and device.The method comprises the steps that running state information of a vehicle is obtained, and the running state information can comprise parameters of the vehicle, running state parameters and the like; running state information of the vehicle is input into the vehicle kinematic model, and a first steering wheel zero deflection angle of the vehicle is determined based on the vehicle kinematic model. And inputting the running state information into a vehicle dynamics model, and determining a second steering wheel zero deflection angle of the vehicle. And determining a third steering wheel zero deflection angle by using the first steering wheel zero deflection angle and the second steering wheel zero deflection angle. And determining the target steering wheel zero deflection angle of the vehicle based on the third steering wheel zero deflection angle. Through the method, the steering wheel zero deflection angle of the vehicle can be automatically determined by using the running state information of the vehicle and the model of the vehicle, manual calibration is not needed, the accuracy of determining the steering wheel zero deflection angle can be improved, and the time for determining the steering wheel zero deflection angle can be shortened.

Description

Technical Field

[0001] The present application relates to the field of autonomous driving technology, and in particular to a method for determining a zero steering wheel angle, a vehicle control method and a device. Background Art

[0002] With the rapid development of the automobile industry, vehicle safety and driving experience have become the focus of attention of consumers and manufacturers. As a key control component for vehicle driving, the accuracy of the steering wheel can affect the followability and safety of the vehicle. In the actual installation of the steering wheel, as well as the hardware structure errors of the steering wheel itself, the problem of zero bias of the steering wheel is common in the vehicle control process. That is, the angle applied to the steering wheel when the vehicle is driving in a straight line is theoretically 0 degrees, but due to the zero bias problem, a certain angle needs to be applied to the steering wheel to ensure that the vehicle drives in a straight line. The zero bias problem of the steering wheel can be characterized by the zero bias angle of the steering wheel, which means the angle that needs to be applied to the steering wheel to maintain the straight driving state of the vehicle.

[0003] With the development of autonomous driving technology, the requirements for the accuracy of the steering wheel zero deflection angle are increasing. Traditionally, the zero deflection angle of the vehicle's steering wheel mainly relies on manual calibration. The staff determines the zero deflection angle of the steering wheel through visual observation and manual adjustment, which is convenient for the subsequent correction of the steering wheel angle. However, there are many disadvantages in manually calibrating the zero deflection angle of the steering wheel, such as taking a long time and large errors in manual operation. Summary of the invention

[0004] In view of this, the present application provides a method for determining a steering wheel zero deflection angle, a vehicle control method and a device, so as to improve the accuracy of determining the steering wheel zero deflection angle and reduce the time for determining the steering wheel zero deflection angle.

[0005] In a first aspect, the present application provides a method for determining a zero deflection angle of a steering wheel, the method comprising:

[0006] Obtain vehicle operating status information;

[0007] Inputting the running state information into a vehicle kinematics model to determine a first steering wheel zero deflection angle of the vehicle;

[0008] Inputting the operating state information into a vehicle dynamics model to determine a second steering wheel zero deflection angle of the vehicle;

[0009] Determining a third steering wheel zero offset angle of the vehicle based on the first steering wheel zero offset angle and the second steering wheel zero offset angle;

[0010] Based on the third steering wheel zero deflection angle, a target steering wheel zero deflection angle of the vehicle is determined.

[0011] In a possible implementation, determining a target steering wheel zero deflection angle of the vehicle based on the third steering wheel zero deflection angle includes:

[0012] Storing the third steering wheel zero deflection angle in a zero deflection angle array, wherein the zero deflection angle array is used to store the third steering wheel zero deflection angle determined at each preset time interval;

[0013] The target steering wheel zero deflection angle is determined based on the plurality of third steering wheel zero deflection angles in the zero deflection angle array.

[0014] In a possible implementation, determining the target steering wheel zero deflection angle based on the plurality of third steering wheel zero deflection angles in the zero deflection angle array includes:

[0015] When the number of the plurality of third steering wheel zero deflection angles in the zero deflection angle array is equal to a preset value, determining the target steering wheel zero deflection angle based on the median or average of the plurality of third steering wheel zero deflection angles;

[0016] When the number of the third steering wheel zero deflection angles in the zero deflection angle array is greater than a preset value, delete the original part of the third steering wheel zero deflection angles in the zero deflection angle array so that the number of the remaining third steering wheel zero deflection angles in the zero deflection angle array is the preset value; determine the target steering wheel zero deflection angle based on the median or average of the remaining third steering wheel zero deflection angles in the zero deflection angle array.

[0017] In a possible implementation, the operating state information includes at least one of vehicle speed, yaw rate, steering wheel angle, wheelbase, and steering gear ratio;

[0018] The step of inputting the operating state information into a vehicle kinematics model to determine a first steering wheel zero offset angle of the vehicle comprises:

[0019] Inputting the wheelbase, the yaw rate and the vehicle speed into the vehicle kinematics model to determine the wheel angle of the vehicle;

[0020] The first steering wheel zero offset angle is determined based on the wheel angle, the steering gear ratio and the steering wheel angle.

[0021] In a possible implementation, inputting the wheelbase, the yaw angular velocity, and the vehicle speed into the vehicle kinematics model to determine the wheel angle of the vehicle includes:

[0022] calculating a ratio of the yaw rate to the vehicle speed;

[0023] An inverse tangent function of the product of the wheelbase and the ratio is calculated to determine the wheel angle.

[0024] In a possible implementation, determining the first steering wheel zero offset angle based on the wheel angle, the steering gear ratio, and the steering wheel angle includes:

[0025] Calculating the product of the wheel angle and the steering gear ratio;

[0026] The difference between the steering wheel angle and the product is calculated to determine the first steering wheel zero deflection angle.

[0027] In a possible implementation, the running state information includes at least one of vehicle speed, yaw rate, steering wheel angle, wheelbase, steering ratio, vehicle body mass, cornering stiffness of front wheel tires, cornering stiffness of rear wheel tires, and lateral acceleration;

[0028] The step of inputting the operating state information into a vehicle dynamics model to determine a second steering wheel zero bias angle of the vehicle comprises:

[0029] Inputting the vehicle speed, the yaw rate, the wheelbase, the vehicle body mass, the cornering stiffness of the front tire, the cornering stiffness of the rear tire, and the lateral acceleration into the vehicle dynamics model to determine the wheel turning angle of the vehicle;

[0030] The second steering wheel zero offset angle is determined based on the wheel angle, the steering gear ratio and the steering wheel angle.

[0031] In a possible implementation, inputting the vehicle speed, the yaw rate, the wheelbase, the vehicle body mass, the cornering stiffness of the front tire, the cornering stiffness of the rear tire, and the lateral acceleration into the vehicle dynamics model to determine the wheel turning angle of the vehicle includes:

[0032] calculating a first ratio of the yaw rate to the vehicle speed;

[0033] calculating a first product of the wheelbase and the first ratio;

[0034] calculating a second product of the vehicle body mass and the lateral acceleration;

[0035] calculating a second ratio of the second product to the cornering stiffness of the front tire;

[0036] calculating a third ratio of the cornering stiffness of the rear tire to the cornering stiffness of the front tire;

[0037] The wheel angle is determined based on the sum of the first product, the second ratio, and the third ratio.

[0038] In a possible implementation, before inputting the operating state information into the vehicle kinematics model, the method further includes:

[0039] Based on the running state information, it is determined that the vehicle is in a straight-line driving state.

[0040] In a second aspect, the present application provides a vehicle control method, the method comprising:

[0041] Obtaining a target steering wheel zero deviation angle of the vehicle, where the target steering wheel zero deviation angle is determined based on the method described in any one of the implementations of the first aspect above;

[0042] Superimposing the target steering wheel zero deflection angle with a preset target steering wheel angle of the vehicle to determine an actual steering wheel angle;

[0043] A steering wheel rotation of the vehicle is controlled based on the actual steering wheel angle.

[0044] In a third aspect, the present application provides a device for determining a zero deflection angle of a steering wheel, the device comprising:

[0045] A first acquisition unit, used to acquire the running status information of the vehicle;

[0046] A first determining unit, configured to input the operating state information into a vehicle kinematics model to determine a first steering wheel zero deflection angle of the vehicle;

[0047] A second determination unit, configured to input the operating state information into a vehicle dynamics model to determine a second steering wheel zero deviation angle of the vehicle;

[0048] a third determining unit, configured to determine a third steering wheel zero offset angle of the vehicle based on the first steering wheel zero offset angle and the second steering wheel zero offset angle;

[0049] The fourth determining unit is configured to determine a target steering wheel zero deflection angle of the vehicle based on the third steering wheel zero deflection angle.

[0050] In a fourth aspect, the present application provides a vehicle control device, the device comprising:

[0051] A second acquisition unit, configured to acquire a target steering wheel zero deviation angle of the vehicle, wherein the target steering wheel zero deviation angle is determined based on the method described in any one of the implementations of the first aspect;

[0052] a fifth determining unit, configured to superimpose the target steering wheel zero deviation angle with a preset target steering wheel angle of the vehicle to determine an actual steering wheel angle;

[0053] A control unit is used to control the steering wheel rotation of the vehicle based on the actual steering wheel angle.

[0054] In a fifth aspect, the present application provides an electronic device, the device comprising: a memory and a processor;

[0055] The memory is used to store relevant program codes;

[0056] The processor is used to call the program code to execute the method for determining the zero deviation angle of the steering wheel described in any one of the implementations of the first aspect or the vehicle control method described in any one of the implementations of the second aspect.

[0057] In a sixth aspect, the present application provides a computer-readable storage medium, which is used to store a computer program, and the computer program is used to execute the method for determining the zero deviation angle of the steering wheel as described in any one of the implementations of the first aspect or the vehicle control method as described in any one of the implementations of the second aspect.

[0058] In the seventh aspect, the present application provides a computer program product, which includes a computer program / instructions. When the computer program / instructions are executed by a processor, the method for determining the zero deviation angle of the steering wheel as described in any one of the implementations of the first aspect or the vehicle control method as described in any one of the implementations of the second aspect is implemented.

[0059] In the above implementation of the present application, in order to perform zero-bias compensation on the vehicle and determine the zero-bias angle of the steering wheel of the vehicle, it is first necessary to obtain the running state information of the vehicle, wherein the running state information may include parameters of the vehicle itself and driving state parameters, etc. Then the running state information of the vehicle is input into the vehicle kinematic model, and the first steering wheel zero-bias angle of the vehicle is determined based on the vehicle kinematic model. After obtaining the first steering wheel zero-bias angle, in order to more accurately determine the steering wheel zero-bias angle, the running state information is input into the vehicle dynamics model to determine the second steering wheel zero-bias angle of the vehicle. Then the first steering wheel zero-bias angle and the second steering wheel zero-bias angle are used to determine the third steering wheel zero-bias angle. Thus, the final target steering wheel zero-bias angle of the vehicle can be determined based on the third steering wheel zero-bias angle, so that the steering wheel of the vehicle can be controlled based on the target steering wheel zero-bias angle later. Through the method provided in the present application, the vehicle's operating status information can be used in combination with the vehicle's kinematic model and dynamic model to automatically determine the two steering wheel zero deflection angles, thereby obtaining the final steering wheel zero deflection angle without manual calibration, which can improve the accuracy of determining the steering wheel zero deflection angle and reduce the time for determining the steering wheel zero deflection angle. In addition, compared with the kinematic model, the dynamic model takes into account the characteristics of the tire, etc., so that the calculated steering wheel zero deflection angle is more accurate. The combination of the two models can cover a variety of working conditions and improve the accuracy of determining the steering wheel zero deflection angle. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. It is obvious that the drawings described below are only some embodiments provided in the present application, and a person skilled in the art can also obtain other drawings based on these drawings.

[0061] Figure 1 A flowchart of a method for determining a zero steering wheel angle provided in an embodiment of the present application.

[0062] Figure 2 A flowchart of another method for determining a zero steering wheel angle provided in an embodiment of the present application.

[0063] Figure 3 A flow chart of a vehicle control method provided in an embodiment of the present application.

[0064] Figure 4 A schematic diagram of an autonomous driving system provided in an embodiment of the present application.

[0065] Figure 5 A schematic diagram of a device for determining a zero steering wheel angle provided in an embodiment of the present application.

[0066] Figure 6 A schematic diagram of a vehicle control device provided in an embodiment of the present application.

[0067] Figure 7 A schematic diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. The described embodiments are only exemplary implementation methods of the present application, not all implementation methods. Those skilled in the art can combine the embodiments of the present application to obtain other embodiments without creative work, and these embodiments are also within the scope of protection of the present application.

[0069] During vehicle driving, the steering wheel is a key control component of the vehicle, and the accuracy of the steering wheel is very important to ensure the stability and safety of the vehicle. In the actual installation of the steering wheel, as well as the errors in the hardware structure of the steering wheel itself, the problem of zero offset of the steering wheel is common in the vehicle control process. Therefore, the vehicle is usually compensated for zero offset angle to ensure the normal driving of the vehicle. The zero offset problem of the steering wheel can usually be characterized by the zero offset angle of the steering wheel. The zero offset angle of the steering wheel represents the angle that needs to be applied to the steering wheel to maintain the straight driving state of the vehicle.

[0070] With the development of autonomous driving technology, vehicles have increasingly higher requirements for the accuracy of steering wheel zero deviation angles. For example, electronic stability control systems, lane keeping assist systems, etc. all rely on precise control of the steering wheel to ensure that they can accurately perceive the driver's input commands or automatic control commands.

[0071] Traditionally, the steering wheel zero deflection angle of vehicles mainly relies on manual calibration, where workers calibrate the steering wheel zero deflection angle through visual observation and manual adjustment. However, manual calibration has many disadvantages, such as taking a long time and large errors in manual operation.

[0072] In order to overcome the above problems, in recent years, the automatic calibration of the zero deflection angle of the steering wheel has been gradually realized by using hardware such as sensors and electronic control units. However, the existing automatic calibration methods usually require additional hardware support. For example, it is necessary to add sensors for calibrating the steering angle to the front wheels of the vehicle. In addition, the calibration accuracy of the sensors will be affected to varying degrees under different environmental conditions, which increases the hardware cost and cannot guarantee the accuracy of the zero deflection angle of the steering wheel.

[0073] Based on this, the embodiment of the present application provides a method for determining the zero deflection angle of the steering wheel, which can improve the accuracy of determining the zero deflection angle of the steering wheel and reduce the time for determining the zero deflection angle of the steering wheel. In the specific implementation, it is first necessary to obtain the running state information of the vehicle, wherein the running state information may include the parameters of the vehicle itself and the driving state parameters, etc. Then the running state information of the vehicle is input into the vehicle kinematic model, and the first steering wheel zero deflection angle of the vehicle is determined based on the vehicle kinematic model. After obtaining the first steering wheel zero deflection angle, in order to more accurately determine the zero deflection angle of the steering wheel, the running state information is input into the vehicle dynamics model to determine the second steering wheel zero deflection angle of the vehicle. Then the first steering wheel zero deflection angle and the second steering wheel zero deflection angle are used to determine the third steering wheel zero deflection angle. Thus, the final target steering wheel zero deflection angle of the vehicle can be determined based on the third steering wheel zero deflection angle, so that the steering wheel of the vehicle can be controlled based on the target steering wheel zero deflection angle later.

[0074] Compared with the traditional manual calibration method, the method provided by the embodiment of the present application can utilize the vehicle's operating status information, combined with the vehicle's kinematic model and dynamic model, to automatically determine the vehicle's steering wheel zero deflection angle, without the need for manual calibration, which can improve the accuracy of determining the steering wheel zero deflection angle and reduce the time for determining the steering wheel zero deflection angle. In addition, compared with the kinematic model, the dynamic model takes into account the tire characteristics, etc., so that the calculated steering wheel zero deflection angle is more accurate. The combination of the two models can cover a variety of working conditions and improve the accuracy of determining the steering wheel zero deflection angle. In order to measure the steering wheel zero deflection angle, the current automatic calibration method requires additional sensor hardware, that is, the newly added sensor is specifically used to serve the steering wheel zero deflection angle and cannot serve other purposes. The method provided by the embodiment of the present application reuses the vehicle's existing sensors to obtain the data required for calculating the steering wheel zero deflection angle, without the need to add additional hardware sensors, which can reduce hardware costs.

[0075] In order to facilitate understanding of the method provided in the embodiments of the present application, a detailed description will be given below in conjunction with the drawings of the embodiments.

[0076] See also Figure 1 , Figure 1 A flowchart of a method for determining a zero steering wheel angle provided in an embodiment of the present application.

[0077] Optionally, the method can be performed by an automatic driving system of a vehicle, where the vehicle represents a vehicle for which a zero steering wheel angle needs to be determined. The method mainly comprises the following steps:

[0078] S101: Acquire vehicle operation status information.

[0079] In the embodiment of the present application, the running state information of the vehicle may include the parameter information of the vehicle itself and the driving state information of the vehicle (i.e., the running data of the vehicle during driving). For example, the parameter information of the vehicle itself may include the wheelbase of the vehicle, the body mass, etc., wherein the wheelbase of the vehicle represents the distance from the center of the front axle to the center of the rear axle of the vehicle, which can be understood as the distance between the center points of the adjacent front and rear wheels on the same side of the vehicle. The driving state information of the vehicle may include vehicle speed, yaw rate, lateral acceleration, steering wheel angle, steering ratio, lateral stiffness of the front tire, lateral stiffness of the rear tire, etc.

[0080] Optionally, the vehicle's automatic driving system may include a variety of sensors for measuring data when the vehicle is traveling. For example, the vehicle's speed sensor may measure the vehicle's speed, and the automatic driving system may obtain the speed measured by the speed sensor. The yaw rate may be measured by the vehicle's inertial sensor, and the automatic driving system may obtain the yaw rate measured by the inertial sensor. The steering wheel angle may be measured by a steering wheel angle sensor, and the automatic driving system may obtain the steering wheel angle from the steering wheel angle sensor. The automatic driving system may obtain the lateral acceleration based on the product of the vehicle speed and the yaw rate. The steering ratio, the lateral stiffness of the front wheel tires, and the lateral stiffness of the rear wheel tires of the vehicle may be obtained from the vehicle's factory data, or may be obtained in advance through experimental measurements. The measurement method may refer to existing materials, and the embodiments of the present application do not limit this. Among them, the sensors required in the above embodiments are all sensors already available in the vehicle itself, and there is no need to add additional sensors for calculating the zero deflection angle of the steering wheel.

[0081] It should be noted that the method of obtaining the vehicle's operating status information provided in the above embodiment is only an exemplary description and is not limited to the above implementation method.

[0082] S102: Inputting the operating state information into the vehicle kinematics model to determine a first steering wheel zero offset angle of the vehicle.

[0083] After the running state information of the vehicle is obtained, the running state information of the vehicle and the vehicle kinematics model may be used to perform calculations to obtain a first steering wheel zero deflection angle.

[0084] Among them, the vehicle kinematic model describes the steering behavior of the vehicle based on geometric relationships and ideal motion assumptions. Based on the vehicle's geometric structure and several operating state parameters, the vehicle's driving process can be abstracted into a simplified kinematic model, and an equivalent relationship between multiple operating state parameters can be established. Therefore, the calculation process based on the kinematic model is simple and more suitable for calculating vehicles at low speeds or under relatively ideal conditions, while the calculation accuracy for vehicles at high speeds is slightly worse.

[0085] S103: Inputting the operating state information into the vehicle dynamics model to determine a second steering wheel zero offset angle of the vehicle.

[0086] Since the vehicle's kinematic model ignores the vehicle's dynamic characteristics, it is more suitable for steering control of vehicles traveling at low speeds. Based on this, in order to accurately determine the vehicle's steering wheel zero angle under a variety of driving conditions, for example, determine the steering wheel zero angle for vehicles in a high-speed state and improve the accuracy of determining the steering wheel zero angle, the embodiment of the present application can also determine the vehicle's second steering wheel zero angle based on the vehicle's dynamics model.

[0087] Among them, the physical characteristics of the vehicle are taken into account when establishing the vehicle dynamics model, such as the side deviation of the tires, the mass distribution of the vehicle body, etc. The vehicle dynamics model not only considers the geometric structure, but also combines mechanical equations to describe the steering behavior of the vehicle while driving, which can more accurately determine the zero deflection angle of the steering wheel of the vehicle.

[0088] In a possible implementation, the vehicle kinematic model and the vehicle dynamics model may be pre-stored in the vehicle's autonomous driving system, for example, in a storage module or a central processing unit in the autonomous driving system, so that the autonomous driving system can call the vehicle kinematic model and the vehicle dynamics model at any time for data processing. During vehicle driving, the autonomous driving system may obtain the vehicle's operating status information in real time, and then substitute the operating status information into the vehicle kinematic model and the vehicle dynamics model for calculation to obtain the first steering wheel zero deflection angle and the second steering wheel zero deflection angle.

[0089] S104: Determine a third steering wheel zero offset angle of the vehicle based on the first steering wheel zero offset angle and the second steering wheel zero offset angle.

[0090] After the first steering wheel zero offset angle and the second steering wheel zero offset angle are obtained respectively by using the vehicle kinematics model and the vehicle dynamics model, the third steering wheel zero offset angle of the vehicle can be determined by combining the first steering wheel zero offset angle and the second steering wheel zero offset angle. For example, the first steering wheel zero offset angle and the second steering wheel zero offset angle can be weighted averaged to determine the third steering wheel zero offset angle of the vehicle.

[0091] S105: Determine a target steering wheel zero deflection angle of the vehicle based on the third steering wheel zero deflection angle.

[0092] After obtaining the third steering wheel zero deflection angle, the third steering wheel zero deflection angle may be processed to determine a final target steering wheel zero deflection angle of the vehicle, so that a subsequent autonomous driving system may control the steering wheel rotation of the vehicle based on the target steering wheel zero deflection angle.

[0093] Optionally, in order to simplify the calculation process and reduce the time for determining the target steering wheel zero deflection angle, after the third steering wheel zero deflection angle is calculated, the third steering wheel zero deflection angle may be determined as the target steering wheel zero deflection angle.

[0094] In one possible implementation, in order to more accurately determine the steering wheel zero angle in combination with the vehicle's driving conditions, the autonomous driving system may periodically obtain the vehicle's operating status information during driving, and determine the first steering wheel zero angle, the second steering wheel zero angle and the third steering wheel zero angle based on the newly acquired operating status information each time, thereby determining the target steering wheel zero angle based on the acquired multiple third steering wheel zero angles, making the target steering wheel zero angle more accurate.

[0095] Compared with the traditional method of manually calibrating the zero deflection angle of the steering wheel, the method provided by the above embodiment can use the running state information and model of the vehicle to automatically determine the zero deflection angle of the steering wheel of the vehicle, without manual calibration, which can improve the accuracy of determining the zero deflection angle of the steering wheel, and can also reduce the time of determining the zero deflection angle of the steering wheel. Compared with the current automatic calibration method, the method provided by the embodiment of the present application does not need to add additional hardware sensors. And the vehicle kinematic model and the vehicle dynamics model are used to determine the zero deflection angle of the steering wheel, which can adapt to a variety of driving environments (such as high-speed and low-speed scenes), ensuring that the automatic driving system has accurate calculation performance at different vehicle speeds, and improving the accuracy of determining the zero deflection angle of the steering wheel. In complex driving environments (such as slippery roads or extreme driving conditions), a single model is prone to errors. By combining the calculation results of the two models, the robustness and reliability of the automatic driving system can be improved, making the steering control of the vehicle steering wheel by the automatic driving system smoother and more accurate.

[0096] Each step in the above process and the technical effects that can be further produced will be described in detail below in conjunction with the embodiments.

[0097] After the autonomous driving system obtains the vehicle's operating status information, there may be noise data or abnormal data in the operating status information, which may affect the subsequent calculation process. Therefore, the autonomous driving system can first perform noise reduction processing on the operating status information to remove noise data and abnormal data. Optionally, low-pass filtering can be performed on data that is prone to change, such as vehicle speed and yaw rate, to suppress high-frequency noise components and retain low-frequency valid data.

[0098] Under ideal conditions, there is no lateral force when the vehicle is in a straight-line driving state, but when the vehicle is in a turning driving state, the lateral force is more obvious. At this time, the error of the data measured by the sensor (such as steering wheel angle, yaw rate, etc.) is larger than the error of the data measured by the sensor when the vehicle is in a straight-line driving state. This is because when the vehicle is in a straight-line driving state, the steering wheel angle and yaw rate are very small, and the changes are also relatively small, so the measurement error will also be relatively small. In order to minimize the lateral error of the data measured by the sensor, the vehicle steering wheel can be calibrated when the vehicle is in a straight-line driving state.

[0099] Based on this, in a possible implementation, in order to more accurately determine the zero offset angle of the steering wheel and realize the zero offset correction of the steering wheel, the zero offset correction can be performed when the vehicle is in a straight-line driving state. Optionally, the automatic driving system can determine whether the vehicle is in a straight-line driving state based on the vehicle's running state information. When it is determined that the vehicle is in a straight-line driving state, the subsequent process of calculating the zero offset angle of the steering wheel is performed.

[0100] In a specific implementation, the autonomous driving system can determine whether the vehicle is in a straight-line driving state based on the vehicle's yaw angular velocity. After the autonomous driving system obtains the vehicle's yaw angular velocity, it can determine whether the yaw angular velocity is less than a first threshold. If the yaw angular velocity is less than the first threshold, it can be determined that the vehicle is in a straight-line driving state; otherwise, it is determined that the vehicle is not in a straight-line driving state. Among them, the embodiment of the present application does not limit the specific value of the first threshold, and can be set in combination with actual needs. For example, the first threshold can be set to 0.01 degrees. That is, when the yaw angular velocity is less than 0.01 degrees, it can be determined that the vehicle is in a straight-line driving state.

[0101] Optionally, the autonomous driving system can also collect key data points of the lane line during the vehicle's driving process, fit a cubic equation for describing the lane line, and then determine whether the vehicle is in a straight-line driving state based on the linear coefficient of the lane line cubic equation. The specific process of fitting the lane line cubic equation can be found in existing materials, and the process will not be described in detail. Specifically, when the linear coefficient of the lane line cubic equation is less than a second threshold, it can be determined that the vehicle is in a straight-line driving state; otherwise, it is determined that the vehicle is not in a straight-line driving state. The embodiment of the present application does not limit the specific value of the second threshold, and it can be set in combination with actual needs.

[0102] By determining that the vehicle is in a straight-line driving state and then executing the subsequent process of determining the steering wheel zero deflection angle, the influence of lateral forces on the vehicle can be minimized, the lateral error can be reduced, and the accuracy of determining the steering wheel zero deflection angle can be further improved.

[0103] The following will introduce in detail step S102 "inputting the operating status information into the vehicle kinematics model to determine the first steering wheel zero deviation angle of the vehicle" in conjunction with the embodiment.

[0104] According to the above embodiments, the running state information of the vehicle may include vehicle speed, yaw rate, steering wheel angle, wheelbase and steering gear ratio of the vehicle, etc. In a possible implementation, after obtaining the above running state information, the first steering wheel zero offset angle of the vehicle may be determined in the following manner: first, the wheelbase, yaw rate and vehicle speed of the vehicle are input into the vehicle kinematic model to determine the wheel angle of the vehicle. Then, based on the wheel angle, steering gear ratio and steering wheel angle, the first steering wheel zero offset angle is determined.

[0105] In a possible implementation, when the wheel angle is calculated using the vehicle kinematic model, it can be implemented in the following way: first calculate the ratio of the yaw rate to the vehicle speed, then calculate the inverse tangent function of the product of the vehicle's wheelbase and the ratio to determine the wheel angle. Alternatively, the product of the yaw rate and the wheelbase can be calculated first, and then the inverse tangent function of the ratio of the product to the vehicle speed can be calculated to determine the wheel angle. The embodiment of the present application does not limit the order of calculation of the various parameters.

[0106] Optionally, after the wheel angle is determined, the product of the wheel angle and the steering gear ratio may be calculated, and then the difference between the steering wheel angle and the product may be calculated, thereby determining the first steering wheel zero offset angle of the vehicle.

[0107] The vehicle kinematics model is used to determine the first steering wheel zero deflection angle, and the calculation process is relatively simple and has strong real-time performance.

[0108] The following will introduce in detail step S103 "inputting the operating status information into the vehicle dynamics model to determine the second steering wheel zero deviation angle of the vehicle" in conjunction with the embodiment.

[0109] The vehicle operation status information may include vehicle speed, yaw rate, steering wheel angle, vehicle wheelbase, steering gear ratio, vehicle body mass, cornering stiffness of front tires, cornering stiffness of rear tires, and lateral acceleration of the vehicle. In a possible implementation, the vehicle speed, yaw rate, wheelbase, vehicle body mass, cornering stiffness of front tires, cornering stiffness of rear tires, and lateral acceleration may be input into a vehicle dynamics model to determine the wheel angle of the vehicle. Then, based on the wheel angle, steering gear ratio, and steering wheel angle, the second steering wheel zero deflection angle is determined.

[0110] Optionally, when calculating the wheel angle using the vehicle dynamics model, it can be achieved in the following ways:

[0111] A1: Calculate the first ratio of the yaw rate to the vehicle speed;

[0112] A2: Calculate the first product of the wheelbase and the first ratio;

[0113] A3: Calculate the second product of the vehicle body mass and the lateral acceleration;

[0114] A4: Calculate a second ratio of the second product to the cornering stiffness of the front tire;

[0115] A5: Calculate the third ratio of the cornering stiffness of the rear tire to the cornering stiffness of the front tire;

[0116] A6: Determine the wheel angle based on the sum of the first product, the second ratio and the third ratio.

[0117] The above steps are only for illustrating the calculation principle of the vehicle kinematic model, and do not limit the execution order of each step. For example, the embodiment of the present application does not limit the order of calculating the first product (A1-A2), the second ratio (A3-A4), and the third ratio (A5).

[0118] In addition, for step A1 and step A2, the above embodiment first calculates the ratio of the yaw angular velocity to the vehicle speed, and then calculates the product of the ratio and the wheelbase. Optionally, the embodiment of the present application may also first calculate the product of the yaw angular velocity and the wheelbase, and then calculate the ratio of the product to the vehicle speed, to obtain the same calculation results as steps A1-step A2.

[0119] Similarly, for steps A3 and A4, the above embodiment first calculates the product of the vehicle body mass and the lateral acceleration, and then calculates the ratio of the product to the cornering stiffness of the front wheel tire. Optionally, the embodiment of the present application may first calculate the ratio of the vehicle body mass to the cornering stiffness of the front wheel tire, and then calculate the product of the ratio and the lateral acceleration, to obtain the same calculation results as steps A3-A4.

[0120] After the wheel angle is determined, the product of the wheel angle and the steering gear ratio may be calculated, and then the difference between the steering wheel angle and the product may be calculated to determine the second steering wheel zero offset angle of the vehicle.

[0121] It should be noted that the embodiments of the present application do not limit the execution order of step S102 and step S103, that is, step S102 can be executed first to determine the first steering wheel zero angle, and then step S103 can be executed to determine the second steering wheel zero angle, or step S103 can be executed first to determine the second steering wheel zero angle, and then step S102 can be executed to determine the first steering wheel zero angle, or step S102 and step S103 can be executed at the same time, that is, the first steering wheel zero angle and the second steering wheel zero angle are determined at the same time, which does not affect the implementation of the embodiments of the present application.

[0122] When the vehicle dynamics model is used to determine the second steering wheel zero bias angle, the tire side bias, the mass distribution of the vehicle body, etc. are also considered based on the geometric structure, and the dynamic characteristics of the vehicle when driving at high speed and turning are described in combination with the mechanical equation, which improves the accuracy of the vehicle dynamics model and can more accurately determine the vehicle's steering wheel zero bias angle. Combining the vehicle kinematic model and the vehicle dynamics model to determine the steering wheel zero bias angle allows the autonomous driving system to adapt to a variety of driving environments (such as high-speed and low-speed scenarios), ensuring that the autonomous driving system has accurate calculation performance for vehicles of different speeds, thereby improving the accuracy of determining the steering wheel zero bias angle.

[0123] After determining the first steering wheel zero angle and the second steering wheel zero angle based on the above embodiments, step S104 “determining the third steering wheel zero angle based on the first steering wheel zero angle and the second steering wheel zero angle” will be described in detail below in conjunction with the embodiments.

[0124] In a possible implementation, after determining the first steering wheel zero deflection angle and the second steering wheel zero deflection angle based on the current operating state information, the first steering wheel zero deflection angle and the second steering wheel zero deflection angle may be weighted averaged to obtain a third steering wheel zero deflection angle. Specifically, a first weight may be assigned to the first steering wheel zero deflection angle in advance, and a second weight may be assigned to the second steering wheel zero deflection angle, wherein the sum of the first weight and the second weight is 1. Then, the product of the first steering wheel zero deflection angle and the first weight, and the product of the second steering wheel zero deflection angle and the second weight are calculated, and then the two products are summed to obtain the third steering wheel zero deflection angle.

[0125] In an embodiment of the present application, a weight can be used to indicate the importance of the corresponding steering wheel zero deflection angle in the calculation, and a larger weight indicates a higher importance of the corresponding steering wheel zero deflection angle, and under different driving conditions, the automatic driving system can also adjust the values ​​of the first weight and the second weight. For example, when the vehicle is in a low-speed driving state, the automatic driving system can set the value of the first weight to be larger and the value of the second weight to be smaller. Since the first weight corresponds to the first steering wheel zero deflection angle calculated by the vehicle kinematic model, and the vehicle kinematic model can accurately calculate the steering wheel zero deflection angle of the vehicle in a low-speed driving state, the value of the first weight can be set to be greater than the value of the second weight, thereby improving the accuracy of determining the steering wheel zero deflection angle. In addition, since the vehicle kinematic model can more accurately calculate the steering wheel zero deflection angle of a vehicle in a high-speed driving state, when the vehicle is in a high-speed driving state, the automatic driving system can set the value of the second weight to be larger and the value of the first weight to be smaller, so as to improve the accuracy of determining the steering wheel zero deflection angle.

[0126] The step S105 “determining a target steering wheel zero deviation angle of the vehicle based on the third steering wheel zero deviation angle” will be described in detail below in conjunction with the embodiments.

[0127] In a possible implementation, in order to simplify the calculation process and reduce the time for determining the target steering wheel zero deflection angle, after the third steering wheel zero deflection angle is calculated, the third steering wheel zero deflection angle may be determined as the target steering wheel zero deflection angle.

[0128] During vehicle driving, the vehicle's driving conditions may change, and the first steering wheel zero offset angle determined based on the vehicle kinematic model or the second steering wheel zero offset angle determined based on the vehicle dynamics model may be erroneous, resulting in a large difference in the third steering wheel zero offset angle obtained between two adjacent acquisition times (separated by a preset time period). In this case, there is an obvious jump in the steering control of the vehicle's steering wheel based on the third steering wheel zero offset angle, which affects the safety and stability of the vehicle's driving, and the control of the vehicle's steering wheel is also inaccurate.

[0129] Therefore, in order to more accurately determine the steering wheel zero deflection angle and achieve precise control of the vehicle, the autonomous driving system can continuously obtain the vehicle's operating status information during driving, and determine the first steering wheel zero deflection angle and the second steering wheel zero deflection angle based on the newly acquired operating status information each time, so that multiple third steering wheel zero deflection angles can be determined based on multiple first steering wheel zero deflection angles and multiple second steering wheel zero deflection angles.

[0130] For example, the automatic driving system can pre-set a preset time period for the vehicle collection interval, that is, obtain the vehicle's current operating status information once every preset time period, and then input the current operating status information into the vehicle kinematic model to determine the vehicle's first steering wheel zero bias angle, and input the current operating status information into the vehicle dynamics model to determine the vehicle's second steering wheel zero bias angle. Then, based on the first steering wheel zero bias angle and the second steering wheel zero bias angle, the third steering wheel zero bias angle is determined. Among them, the embodiment of the present application does not limit the preset time period for interval collection, and can be set in combination with the actual application scenario, and the preset time period can also be adjusted in combination with the vehicle's driving conditions. For example, it can be set to obtain the vehicle's current operating status information once every 2 seconds, or it can also be set to obtain the vehicle's current operating status information once every 10 seconds.

[0131] Based on this, the embodiment of the present application may consider the third steering wheel zero deviation angle determined by multiple preset time periods at intervals to determine the target steering wheel zero deviation angle for controlling the steering wheel.

[0132] In a possible implementation, the third steering wheel zero deflection angle determined each time can be stored in a zero deflection angle array, wherein the zero deflection angle array can be pre-set for the automatic driving system and is used to store the determined third steering wheel zero deflection angle. That is, after collecting the running status information of the vehicle once every preset time period, the determined third steering wheel zero deflection angle can be stored in the zero deflection angle array. Then, based on the multiple third steering wheel zero deflection angles in the zero deflection angle array, the target steering wheel zero deflection angle is determined.

[0133] In actual application scenarios, since the steering wheel zero deflection angle of the vehicle will not be too large, when the calculated third steering wheel zero deflection angle is large, there may be a large error, then the third steering wheel zero deflection angle can be deleted, and the third steering wheel zero deflection angle is not stored in the zero deflection angle array. In specific implementation, the steering wheel zero deflection angle threshold can be pre-set, and after determining the third steering wheel zero deflection angle, the third steering wheel zero deflection angle and the steering wheel zero deflection angle threshold are compared. When the third steering wheel zero deflection angle is less than or equal to the steering wheel zero deflection angle threshold, the third steering wheel zero deflection angle is stored in the zero deflection angle array. When the third steering wheel zero deflection angle is greater than the steering wheel zero deflection angle threshold, the third steering wheel zero deflection angle is discarded, that is, the third steering wheel zero deflection angle is not stored in the zero deflection angle array.

[0134] Since the automatic driving system can continuously obtain the running state information of the vehicle, in order to achieve higher calculation efficiency and accuracy, the preset value of the upper limit of the number of third steering wheel zero deflection angles stored in the zero deflection angle array can be pre-set. In the initial stage, when the number of third steering wheel zero deflection angles stored in the zero deflection angle array is less than the preset value, the target steering wheel zero deflection angle can be not calculated, that is, the zero deflection correction of the vehicle's steering wheel is not performed. In the process of continuously obtaining new running state information of the vehicle, the newly determined third steering wheel zero deflection angle is also continuously stored in the zero deflection angle array. When the number of multiple third steering wheel zero deflection angles stored in the zero deflection angle array reaches the preset value, the target steering wheel zero deflection angle can be determined based on the median of multiple third steering wheel zero deflection angles or the average of multiple third steering wheel zero deflection angles. That is, the median of multiple third steering wheel zero deflection angles can be determined as the target steering wheel zero deflection angle, or the average of multiple third steering wheel zero deflection angles can also be calculated as the target steering wheel zero deflection angle.

[0135] Optionally, before calculating the target steering wheel zero deflection angle, in order to further reduce the error and improve the accuracy and stability of the vehicle steering wheel control, the largest third steering wheel zero deflection angle and the smallest third steering wheel zero deflection angle in the zero deflection angle array may be removed, and the target steering wheel zero deflection angle may be determined based on the remaining multiple third steering wheel zero deflection angles in the zero deflection angle array. For example, the target steering wheel zero deflection angle may be determined based on the median or average of the remaining multiple third steering wheel zero deflection angles in the zero deflection angle array.

[0136] When the number of the third steering wheel zero deflection angles stored in the zero deflection angle array reaches the preset value, the automatic driving system still obtains the running state information of the vehicle, that is, it will also determine a new third steering wheel zero deflection angle and store it in the zero deflection angle array, so that the number of the third steering wheel zero deflection angles in the zero deflection angle array is greater than the preset value. In a possible implementation, when the number of the third steering wheel zero deflection angles in the zero deflection angle array is greater than the preset value, part of the original third steering wheel zero deflection angles in the zero deflection angle array can be deleted, so that the number of the remaining third steering wheel zero deflection angles in the zero deflection angle array is the preset value. Among them, the original third steering wheel zero deflection angle represents a plurality of third steering wheel zero deflection angles other than the latest stored third steering wheel zero deflection angle. Deleting part of the original third steering wheel zero deflection angle can be deleting any one of the original plurality of third steering wheel zero deflection angles, or can be deleting the earliest stored third steering wheel zero deflection angle among the original plurality of third steering wheel zero deflection angles.

[0137] After deleting part of the original third steering wheel zero deflection angles, the target steering wheel zero deflection angle may be determined based on the median or average of the remaining plurality of third steering wheel zero deflection angles in the zero deflection angle array.

[0138] Through the method provided by the embodiment of the present application, the vehicle's operating status information and the vehicle's model can be used to automatically determine the vehicle's steering wheel zero deviation angle, without the need for manual calibration, which can improve the accuracy of determining the steering wheel zero deviation angle and reduce the time for determining the steering wheel zero deviation angle. In addition, the vehicle operating status information used is data that the automatic driving system can obtain through the existing sensors on the vehicle. There is no need to add additional sensors for measurement in order to determine the steering wheel zero deviation angle, which can reduce hardware costs. The vehicle kinematic model and the vehicle dynamics model are combined to determine the steering wheel zero deviation angle, so that the automatic driving system can adapt to a variety of driving environments, ensure that the automatic driving system has accurate calculation performance at different vehicle speeds, and improve the accuracy of determining the steering wheel zero deviation angle and the adaptability to a variety of driving environments. By combining the calculation results of the two models, the robustness and reliability of the automatic driving system can be improved, making the subsequent automatic driving system's steering control of the vehicle steering wheel smoother and more accurate.

[0139] Based on the above method embodiment, the present application embodiment also provides a method for determining the zero deflection angle of the steering wheel. Figure 2 , Figure 2 A flowchart of another method for determining a zero steering wheel angle provided in an embodiment of the present application.

[0140] The method may include the following steps:

[0141] S201: Acquire the running status information of the vehicle at every preset time period.

[0142] S202: Based on the running status information, determine whether the vehicle is in a straight-line driving state; if so, execute step S203; otherwise, jump to execute step S201.

[0143] S203: Inputting the operating state information into the vehicle kinematics model to determine the first steering wheel zero offset angle of the vehicle.

[0144] S204: Inputting the operating state information into the vehicle dynamics model to determine a second steering wheel zero offset angle of the vehicle.

[0145] S205: Taking a weighted average of the first steering wheel zero deflection angle and the second steering wheel zero deflection angle to determine a third steering wheel zero deflection angle.

[0146] S206: Storing the third steering wheel zero deflection angle in a zero deflection angle array, and determining a target steering wheel zero deflection angle based on a plurality of third steering wheel zero deflection angles in the zero deflection angle array.

[0147] The specific implementation process of each step can be found in the above method embodiment, which will not be elaborated here.

[0148] Based on the above method embodiment, the present application embodiment also provides a vehicle control method. Figure 3 , Figure 3 A flow chart of a vehicle control method provided in an embodiment of the present application.

[0149] The method can be executed by an autonomous driving system, which has the function of controlling the steering wheel of the vehicle to turn.

[0150] The method may include the following steps:

[0151] S301: Obtain a target steering wheel zero deflection angle of the vehicle.

[0152] The target steering wheel zero deflection angle is obtained based on the method for determining the steering wheel zero deflection angle provided in the above method embodiment.

[0153] S302: Superimpose the target steering wheel zero angle with the preset target steering wheel angle of the vehicle to determine the actual steering wheel angle.

[0154] The preset target steering wheel angle can be expressed as the angle at which the steering wheel is controlled to rotate under the ideal condition that the vehicle does not have a zero steering wheel angle. Since the angle that needs to be applied to the steering wheel when controlling the vehicle to drive in a straight line is the target zero steering wheel angle, when controlling the vehicle to drive according to the preset target steering wheel angle, the target zero steering wheel angle needs to be superimposed on the preset target steering wheel angle to obtain the actual steering wheel angle.

[0155] In a possible application scenario, when the target steering wheel zero deflection angle is 2 degrees to the left, if the vehicle needs to be controlled to drive at a 10-degree left deflection, the actual steering wheel angle input to the steering wheel is 10+2=12 degrees.

[0156] S303: Controlling the steering wheel rotation of the vehicle based on the actual steering wheel angle.

[0157] After obtaining the actual steering wheel angle, the autonomous driving system controls the steering wheel rotation of the vehicle according to the actual steering wheel angle. For example, the autonomous driving system may send the actual steering wheel angle to a steering wheel control mechanism, and the steering wheel control mechanism controls the steering wheel rotation based on the actual steering wheel angle.

[0158] After obtaining the target steering wheel zero angle through the method for determining the steering wheel zero angle provided in the embodiment of the present application, the automatic driving system can control the steering wheel rotation of the vehicle based on the target steering wheel zero angle, thereby improving the accuracy of steering wheel control.

[0159] Based on the above method embodiment, the present application embodiment also provides an automatic driving system. Figure 4 As shown, Figure 4 A schematic diagram of an autonomous driving system provided in an embodiment of the present application.

[0160] Among them, the automatic driving system can obtain the vehicle's operating status information and realize control of the vehicle.

[0161] The autonomous driving system 400 may include: a data acquisition module 401 and a processing module 402;

[0162] The data acquisition module 401 is used to acquire the running status information of the vehicle;

[0163] Optionally, the data acquisition module may receive data collected by the sensor and convert the collected data into digital signals so as to be sent to the processing module 402 for data processing.

[0164] Processing module 402 is used to input the operating status information into the vehicle kinematic model to determine the first steering wheel zero offset angle of the vehicle; input the operating status information into the vehicle dynamics model to determine the second steering wheel zero offset angle of the vehicle; determine the third steering wheel zero offset angle of the vehicle based on the first steering wheel zero offset angle and the second steering wheel zero offset angle; and determine the target steering wheel zero offset angle of the vehicle based on the third steering wheel zero offset angle.

[0165] Optionally, the processing module 402 may include a zero bias calculation module and a zero bias output module; wherein the zero bias calculation module is used to input the operating state information into the vehicle kinematic model to determine the first steering wheel zero bias angle of the vehicle; and input the operating state information into the vehicle dynamics model to determine the second steering wheel zero bias angle of the vehicle; and based on the first steering wheel zero bias angle and the second steering wheel zero bias angle, determine the third steering wheel zero bias angle of the vehicle. The zero bias output module is used to determine the target steering wheel zero bias angle of the vehicle based on the third steering wheel zero bias angle.

[0166] Optionally, the processing module 402 may be a central processing unit (CPU), which may obtain the vehicle's operating state information from the data acquisition module, and then determine the vehicle's target steering wheel zero deflection angle using the operating state information and the vehicle kinematics model and the vehicle dynamics model. The vehicle kinematics model and the vehicle dynamics model may be pre-stored in the central processing unit so that the central processing unit can call them at any time.

[0167] In a possible implementation, the automatic driving system may further include a communication interface module for exchanging data with a vehicle-mounted controller area network (CAN) network or other devices. For example, the communication interface module may obtain the target steering wheel zero deviation angle of the vehicle from the central processing unit, and then send the target steering wheel zero deviation angle to the steering wheel control mechanism, which controls the steering wheel rotation based on the target steering wheel zero deviation angle. Optionally, the communication interface module may also receive the vehicle's operating status information obtained by the data acquisition module, and then send the operating status information to the vehicle's fault diagnosis module to diagnose the vehicle's operating status.

[0168] In a possible implementation, the autonomous driving system may further include a storage module for storing vehicle-related data. For example, the storage module may obtain and store the vehicle's operating status information from the data acquisition module, and may also obtain and store the target steering wheel zero deflection angle calculated by the central processing unit.

[0169] In addition, the present application also provides a device for determining the zero deflection angle of a steering wheel. Figure 5 As shown, Figure 5 A schematic diagram of a device for determining a zero steering wheel angle provided in an embodiment of the present application.

[0170] The device 500 comprises:

[0171] A first acquisition unit 501 is used to acquire the running status information of the vehicle;

[0172] A first determining unit 502 is used to input the running state information into a vehicle kinematics model to determine a first steering wheel zero deviation angle of the vehicle;

[0173] A second determining unit 503 is used to input the operating state information into a vehicle dynamics model to determine a second steering wheel zero deviation angle of the vehicle;

[0174] A third determining unit 504 is configured to determine a third steering wheel zero angle of the vehicle based on the first steering wheel zero angle and the second steering wheel zero angle;

[0175] The fourth determining unit 505 is configured to determine a target steering wheel zero angle of the vehicle based on the third steering wheel zero angle.

[0176] In a possible implementation, the fourth determination unit 505 is specifically used to store the third steering wheel zero deflection angle in a zero deflection angle array, and the zero deflection angle array is used to store the third steering wheel zero deflection angle determined at each preset time period; based on the multiple third steering wheel zero deflection angles in the zero deflection angle array, the target steering wheel zero deflection angle is determined.

[0177] In a possible implementation, the fourth determination unit 505 is specifically used to determine the target steering wheel zero deflection angle based on the median or average of the plurality of third steering wheel zero deflection angles when the number of the plurality of third steering wheel zero deflection angles in the zero deflection angle array is equal to a preset value; when the number of the plurality of third steering wheel zero deflection angles in the zero deflection angle array is greater than the preset value, delete part of the original third steering wheel zero deflection angles in the zero deflection angle array so that the number of the plurality of third steering wheel zero deflection angles remaining in the zero deflection angle array is the preset value; and determine the target steering wheel zero deflection angle based on the median or average of the plurality of third steering wheel zero deflection angles remaining in the zero deflection angle array.

[0178] In a possible implementation, the operating state information includes at least one of vehicle speed, yaw rate, steering wheel angle, wheelbase, and steering gear ratio;

[0179] The first determination unit 502 is specifically used to input the wheelbase, the yaw angular velocity and the vehicle speed into the vehicle kinematic model to determine the wheel angle of the vehicle; and determine the first steering wheel zero bias angle based on the wheel angle, the steering gear ratio and the steering wheel angle.

[0180] In a possible implementation, the first determining unit 502 is specifically configured to calculate a ratio of the yaw rate to the vehicle speed;

[0181] An inverse tangent function of the product of the wheelbase and the ratio is calculated to determine the wheel angle.

[0182] In a possible implementation, the first determination unit 502 is specifically configured to calculate the product of the wheel angle and the steering gear ratio; calculate the difference between the steering wheel angle and the product, and determine the first steering wheel zero offset angle.

[0183] In a possible implementation, the running state information includes at least one of vehicle speed, yaw rate, steering wheel angle, wheelbase, steering ratio, vehicle body mass, cornering stiffness of front wheel tires, cornering stiffness of rear wheel tires, and lateral acceleration;

[0184] The second determination unit 503 is specifically used to input the vehicle speed, the yaw angular velocity, the wheelbase, the vehicle body mass, the cornering stiffness of the front wheel tire, the cornering stiffness of the rear wheel tire and the lateral acceleration into the vehicle dynamics model to determine the wheel angle of the vehicle; and determine the second steering wheel zero bias angle based on the wheel angle, the steering gear ratio and the steering wheel angle.

[0185] In a possible implementation, the second determining unit 503 is specifically configured to calculate a first ratio of the yaw angular velocity to the vehicle speed;

[0186] calculating a first product of the wheelbase and the first ratio;

[0187] calculating a second product of the vehicle body mass and the lateral acceleration;

[0188] calculating a second ratio of the second product to the cornering stiffness of the front tire;

[0189] calculating a third ratio of the cornering stiffness of the rear tire to the cornering stiffness of the front tire;

[0190] The wheel angle is determined based on the sum of the first product, the second ratio, and the third ratio.

[0191] In a possible implementation, the device further includes a sixth determination unit; before inputting the operating state information into the vehicle kinematic model, the sixth determination unit is used to determine whether the vehicle is in a straight-line driving state based on the operating state information.

[0192] In addition, the present application also provides a vehicle control device. Figure 6 As shown, Figure 6 A schematic diagram of a vehicle control device provided in an embodiment of the present application.

[0193] The device 600 comprises:

[0194] A second acquisition unit 601 is used to acquire a target steering wheel zero deflection angle of the vehicle, where the target steering wheel zero deflection angle is determined based on the method for determining the steering wheel zero deflection angle described in the above method embodiment;

[0195] A fifth determining unit 602 is configured to superimpose the target steering wheel zero deviation angle with a preset target steering wheel angle of the vehicle to determine an actual steering wheel angle;

[0196] The control unit 603 is used to control the steering wheel rotation of the vehicle based on the actual steering wheel angle.

[0197] Based on the above method embodiment and device embodiment, the present application embodiment further provides an electronic device, which will be described below in conjunction with the accompanying drawings.

[0198] See also Figure 7 , Figure 7 A schematic diagram of an electronic device provided in an embodiment of the present application.

[0199] The device 700 includes: a memory 701 and a processor 702;

[0200] The memory 701 is used to store relevant program codes;

[0201] The processor 702 is used to call the program code to execute the method for determining the zero deviation angle of the steering wheel or the vehicle control method described in the above method embodiment.

[0202] In addition, an embodiment of the present application also provides a computer-readable storage medium, which is used to store a computer program, and the computer program is used to execute the method for determining the zero deviation angle of the steering wheel or the vehicle control method described in the above method embodiment.

[0203] An embodiment of the present application also provides a computer program product, which includes a computer program / instruction. When the computer program / instruction is executed by a processor, the method for determining the zero deviation angle of the steering wheel or the vehicle control method described in the above method embodiment is implemented.

[0204] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can refer to each other. In particular, for the system or device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The device embodiment described above is only exemplary, in which the units or modules described as separate components may or may not be physically separated, and the components displayed as units or modules may or may not be physical modules, that is, they may be located in one place, or they may be distributed on multiple network units, and some or all of the units or modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative work.

[0205] The flowchart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the method, device and equipment etc. of various embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or the flowchart, and the combination of the boxes in the block diagram and / or the flowchart can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0206] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "At least one of the following (items)" or similar expressions refers to any combination of these items, including any combination of single items (items) or plural items (items). For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0207] It should also be noted that, in this application, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0208] The steps of the method or algorithm described in conjunction with the embodiments disclosed in this application can be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module can be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0209] The above description of the disclosed embodiments enables professionals and technicians in the field to implement or use the present application. Various modifications to these embodiments will be apparent to professionals and technicians in the field, and the general principles defined in this application can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown in the present application, but will conform to the widest range consistent with the principles and novel features disclosed in the present application.

Claims

1. A method for determining a zero deflection angle of a steering wheel, characterized in that: The method comprises: Obtain vehicle operating status information; Inputting the running state information into a vehicle kinematics model to determine a first steering wheel zero deflection angle of the vehicle; Inputting the operating state information into a vehicle dynamics model to determine a second steering wheel zero deflection angle of the vehicle; Determining a third steering wheel zero offset angle of the vehicle based on the first steering wheel zero offset angle and the second steering wheel zero offset angle; Based on the third steering wheel zero deflection angle, a target steering wheel zero deflection angle of the vehicle is determined.

2. The method according to claim 1, characterized in that: The step of determining a target steering wheel zero deflection angle of the vehicle based on the third steering wheel zero deflection angle comprises: Storing the third steering wheel zero deflection angle in a zero deflection angle array, wherein the zero deflection angle array is used to store the third steering wheel zero deflection angle determined at each preset time interval; The target steering wheel zero deflection angle is determined based on the plurality of third steering wheel zero deflection angles in the zero deflection angle array.

3. The method according to claim 2, characterized in that The step of determining the target steering wheel zero deflection angle based on the plurality of third steering wheel zero deflection angles in the zero deflection angle array comprises: When the number of the plurality of third steering wheel zero deflection angles in the zero deflection angle array is equal to a preset value, determining the target steering wheel zero deflection angle based on the median or average of the plurality of third steering wheel zero deflection angles; When the number of the third steering wheel zero deflection angles in the zero deflection angle array is greater than a preset value, delete the original part of the third steering wheel zero deflection angles in the zero deflection angle array so that the number of the remaining third steering wheel zero deflection angles in the zero deflection angle array is the preset value; determine the target steering wheel zero deflection angle based on the median or average of the remaining third steering wheel zero deflection angles in the zero deflection angle array.

4. The method according to claim 1, characterized in that The operating state information includes at least one of vehicle speed, yaw rate, steering wheel angle, wheelbase and steering gear ratio; The step of inputting the operating state information into a vehicle kinematics model to determine a first steering wheel zero offset angle of the vehicle comprises: Inputting the wheelbase, the yaw rate and the vehicle speed into the vehicle kinematics model to determine the wheel angle of the vehicle; The first steering wheel zero offset angle is determined based on the wheel angle, the steering gear ratio and the steering wheel angle.

5. The method according to claim 4, characterized in that The step of inputting the wheelbase, the yaw rate, and the vehicle speed into the vehicle kinematics model to determine the wheel angle of the vehicle includes: calculating a ratio of the yaw rate to the vehicle speed; An inverse tangent function of the product of the wheelbase and the ratio is calculated to determine the wheel angle.

6. The method according to claim 1, characterized in that The running state information includes at least one of vehicle speed, yaw rate, steering wheel angle, wheelbase, steering ratio, vehicle body mass, cornering stiffness of front wheel tires, cornering stiffness of rear wheel tires, and lateral acceleration; The step of inputting the operating state information into a vehicle dynamics model to determine a second steering wheel zero bias angle of the vehicle comprises: Inputting the vehicle speed, the yaw rate, the wheelbase, the vehicle body mass, the cornering stiffness of the front tire, the cornering stiffness of the rear tire, and the lateral acceleration into the vehicle dynamics model to determine the wheel turning angle of the vehicle; The second steering wheel zero offset angle is determined based on the wheel angle, the steering gear ratio and the steering wheel angle.

7. The method according to claim 6, characterized in that The step of inputting the vehicle speed, the yaw rate, the wheelbase, the vehicle body mass, the cornering stiffness of the front tire, the cornering stiffness of the rear tire, and the lateral acceleration into the vehicle dynamics model to determine the wheel turning angle of the vehicle comprises: calculating a first ratio of the yaw rate to the vehicle speed; calculating a first product of the wheelbase and the first ratio; calculating a second product of the vehicle body mass and the lateral acceleration; calculating a second ratio of the second product to the cornering stiffness of the front tire; calculating a third ratio of the cornering stiffness of the rear tire to the cornering stiffness of the front tire; The wheel angle is determined based on the sum of the first product, the second ratio, and the third ratio.

8. The method according to claim 1, characterized in that Before inputting the operating state information into the vehicle kinematics model, the method further includes: Based on the running state information, it is determined that the vehicle is in a straight-line driving state.

9. A vehicle control method, characterized in that: The method comprises: Obtaining a target steering wheel zero deflection angle of the vehicle, wherein the target steering wheel zero deflection angle is determined based on the method according to any one of claims 1 to 8; Superimposing the target steering wheel zero deflection angle with a preset target steering wheel angle of the vehicle to determine an actual steering wheel angle; A steering wheel rotation of the vehicle is controlled based on the actual steering wheel angle.

10. A device for determining a zero deflection angle of a steering wheel, characterized in that: The device comprises: A first acquisition unit, used to acquire the running status information of the vehicle; A first determining unit, configured to input the operating state information into a vehicle kinematics model to determine a first steering wheel zero deflection angle of the vehicle; A second determination unit, configured to input the operating state information into a vehicle dynamics model to determine a second steering wheel zero deviation angle of the vehicle; a third determining unit, configured to determine a third steering wheel zero offset angle of the vehicle based on the first steering wheel zero offset angle and the second steering wheel zero offset angle; The fourth determining unit is configured to determine a target steering wheel zero deflection angle of the vehicle based on the third steering wheel zero deflection angle.

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