Vehicle control method, medium and vehicle

Abstract

The invention relates to a vehicle control method, a medium and a vehicle, and belongs to the technical field of vehicle control, and the method comprises the steps: determining the tracking deviation between the position of the vehicle and the planned path of the vehicle, and controlling the output torque of four-wheel independent motors of the vehicle according to the tracking deviation, so that the vehicle returns to the planned path. Therefore, when the vehicle tracks the tracking deviation generated when the vehicle runs in the planned path, the vehicle can return to the planned path by controlling the output torque of the four-wheel independent motor, so that a new path does not need to be planned again, and the experience of a driver is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of vehicle control technology, and in particular, to a vehicle control method, a medium and a vehicle. Background Art

[0002] The power steering system (EPS) of traditional vehicles is based on the Ackerman steering model. When the steering wheel angle is fixed, the vehicle's driving trajectory is approximately circular, and the driving trajectory can be changed by adjusting the steering wheel angle. In the autonomous driving scenario, the vehicle follows a pre-planned path. When the vehicle has a tracking deviation, it needs to control the vehicle to return to the path, but the power steering system sometimes cannot control the vehicle to return to the path, resulting in the need to re-plan a new path. Summary of the invention

[0003] The purpose of the present disclosure is to provide a vehicle control method, a medium and a vehicle, so as to control the vehicle to return to the planned path when a tracking deviation occurs in the vehicle tracking planned path.

[0004] A first aspect of an embodiment of the present disclosure provides a vehicle control method, including:

[0005] Determining a tracking deviation between the position of the vehicle and a planned path of the vehicle;

[0006] According to the tracking deviation, the four-wheel independent motors of the vehicle are controlled to output torque so as to return the vehicle to the planned path.

[0007] Optionally, according to the tracking deviation, controlling the output torque of the four-wheel independent motors of the vehicle to return the vehicle to the planned path includes:

[0008] Determine a first path point of the preview position of the vehicle on the planned path;

[0009] According to the first path point and the tracking deviation, the four-wheel independent motors of the vehicle are controlled to output torque so that the vehicle returns to the planned path.

[0010] Optionally, the method further comprises:

[0011] Obtaining speed information of the vehicle;

[0012] Determining a first path point of the preview position of the vehicle on the planned path includes:

[0013] Determining a second path point corresponding to the position of the vehicle on the planned path;

[0014] The first path point is determined according to the second path point and the vehicle speed information.

[0015] Optionally, determining the first path point according to the second path point and the vehicle speed information includes:

[0016] Determining a preview distance according to the vehicle speed information;

[0017] Determine the first path point according to the second path point and the preview distance.

[0018] Optionally, determining the first path point according to the second path point and the preview distance includes:

[0019] Determining the preview position on the planned path according to the second path point and the preview distance;

[0020] Determining a first trajectory point adjacent to the preview position on the planned path;

[0021] interpolating between the first trajectory points to obtain a plurality of first data points;

[0022] The first path point is determined based on a first data point adjacent to the preview position.

[0023] Optionally, determining a tracking deviation between the position of the vehicle and a planned path of the vehicle includes:

[0024] Determining a reference data point adjacent to the position of the vehicle on the planned path;

[0025] The tracking deviation is determined according to the posture information corresponding to the position of the vehicle and the reference data point.

[0026] Optionally, determining a reference data point adjacent to the position of the vehicle on the planned path includes:

[0027] Determining a second trajectory point adjacent to the position of the vehicle on the planned path;

[0028] interpolating between the second trajectory points to obtain a plurality of second data points;

[0029] A data point whose distance from the position of the vehicle is less than or equal to a distance threshold is determined among the plurality of second data points as the reference data point.

[0030] Optionally, according to the tracking deviation, controlling the output torque of the four-wheel independent motors of the vehicle to return the vehicle to the planned path includes:

[0031] Determining a required steering wheel angle required for the vehicle to return to the planned path according to the tracking deviation;

[0032] According to the required steering wheel angle, the steering wheel angle is controlled, and the output torque of the four-wheel independent motor is controlled so that the sum of the steering wheel angle and the compensation angle corresponding to the output torque of the four-wheel independent motor meets the required steering wheel angle.

[0033] Optionally, according to the required steering wheel angle, controlling the steering wheel angle and controlling the output torque of the four-wheel independent motors include:

[0034] According to the required steering wheel angle, controlling the steering wheel angle to remain unchanged, and determining the difference between the steering wheel angle and the required steering wheel angle as the angle to be compensated;

[0035] The four-wheel independent motors are controlled to output torque to compensate for the turning angle to be compensated.

[0036] Optionally, according to the required steering wheel angle, controlling the steering wheel angle and controlling the output torque of the four-wheel independent motors include:

[0037] When the required steering wheel angle is less than or equal to the maximum steering wheel angle, the steering wheel angle is controlled to be gradually increased according to the required steering wheel angle, and the four-wheel independent motors are controlled to output torque to compensate for the difference between the increased steering wheel angle and the required steering wheel angle;

[0038] When the required steering wheel angle is greater than the maximum steering wheel angle, the steering wheel angle is controlled to increase to the maximum steering wheel angle, and the four-wheel independent motors are controlled to output torque to compensate for the difference between the maximum steering wheel angle and the required steering wheel angle.

[0039] Optionally, the method further comprises:

[0040] Acquire the position information of the vehicle, the parking space information and the obstacle information around the vehicle;

[0041] Trajectory planning is performed according to the posture information, the parking space information, the obstacle information, and a target turning radius when the vehicle is driven by four-wheel independent motors to obtain the planned path, wherein the target turning radius is smaller than a turning radius when the vehicle turns at a maximum steering wheel angle.

[0042] Optionally, determining a second path point corresponding to the position of the vehicle on the planned path includes:

[0043] Obtaining the position information and planned path of the vehicle;

[0044] According to the position information, a second path point corresponding to the position of the vehicle is determined on the planned path.

[0045] A second aspect of an embodiment of the present disclosure provides a computer-readable storage medium having computer program instructions stored thereon. When the program instructions are executed by a processor, the vehicle control method provided by the first aspect of the embodiment of the present disclosure is implemented.

[0046] A third aspect of the embodiments of the present disclosure provides a vehicle, comprising:

[0047] A storage device for storing a computer program;

[0048] A processing device is used to execute the computer program to implement the vehicle control method provided in the first aspect of the embodiment of the present disclosure.

[0049] Optionally, the vehicle includes four motors, each of which drives a corresponding wheel.

[0050] In the disclosed embodiment, the tracking deviation between the vehicle's position and the vehicle's planned path is determined, and based on the tracking deviation, the output torque of the vehicle's four-wheel independent motors is controlled to make the vehicle return to the planned path. In this way, when the vehicle generates a tracking deviation while following the planned path, the output torque of the four-wheel independent motors can be controlled to make the vehicle return to the planned path, thereby eliminating the need to re-plan a new path and improving the driver's experience.

[0051] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0053] Figure 1 The present invention is a flow chart of a vehicle control method according to an exemplary embodiment.

[0054] Figure 2 The present invention is a flowchart of a method for determining a first path point in a vehicle control method according to an exemplary embodiment.

[0055] Figure 3 The present invention is a flowchart of a method for determining reference data points in a vehicle control method according to an exemplary embodiment.

[0056] Figure 4 The present invention is a flowchart of a method for determining a target turning radius in a vehicle control method according to an exemplary embodiment.

[0057] Figure 5 is a block diagram of a vehicle control device according to an exemplary embodiment.

[0058] Figure 6is a block diagram of a vehicle control system according to an exemplary embodiment.

[0059] Figure 7 is a block diagram of a vehicle according to an exemplary embodiment. DETAILED DESCRIPTION

[0060] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0061] The power steering system (EPS) of traditional vehicles is based on the Ackerman steering model. The larger the steering wheel angle, the smaller the corresponding turning radius; the smaller the steering wheel angle, the larger the corresponding turning radius. The driving trajectory is changed by adjusting the steering wheel angle. When the steering wheel angle reaches the maximum, the turning radius cannot be reduced any more. In the case of a vehicle with four independent motors, the driving trajectory of the vehicle can be changed through the power steering system, or the driving trajectory of the vehicle can be changed by combining the power steering system to control the steering wheel angle and adjust the torque size and direction of the four independent motors.

[0062] In the related art, the turning radius when the vehicle is turned by controlling the steering through the power steering system combined with the output torque of the four-wheel independent motors can be smaller than the turning radius when the steering wheel is turned at the maximum angle only by the power steering system. If the steering wheel angle is controlled only by the power steering system and the planned path is tracked, when the turning radius corresponding to the curvature in the planned path is smaller than the turning radius when the steering wheel is turned at the maximum angle, a large tracking deviation will occur. When there is a tracking deviation during the vehicle tracking the planned path, the steering wheel angle can be quickly adjusted through the power steering system to control the vehicle to return to the tracking planned path, but too drastic changes in the steering wheel angle will increase the shaking of the vehicle body and affect the driver's driving experience. If the steering wheel angle has reached the maximum value, the power steering system can no longer compensate for the tracking deviation by increasing the steering wheel angle.

[0063] Based on the problems existing in the related art, the present disclosure provides a vehicle control method, a medium and a vehicle.

[0064] See also Figure 1 , Figure 1 is a flow chart of a vehicle control method according to an exemplary embodiment. Figure 1 As shown, the following steps are included.

[0065] S101. Determine a tracking deviation between a position of a vehicle and a planned path of the vehicle.

[0066] For example, during the driving process, the vehicle can plan a safe and collision-free planned path through the information required for planning the driving path and the algorithm for planning the driving path. The planned path includes multiple trajectory points, each of which includes information such as curvature information, turning radius, vehicle heading angle, driving speed and driving distance. The tracking deviation when the vehicle follows the planned path can be determined based on the path points on the planned path and the trajectory points on the planned path where the vehicle is located.

[0067] S102: Control the output torque of the four-wheel independent motors of the vehicle according to the tracking deviation to make the vehicle return to the planned path.

[0068] For example, when a tracking deviation occurs or is likely to occur during vehicle driving, the vehicle's four-wheel independent motor output torque can be controlled, such as controlling the driving direction, forward or backward, speed, acceleration or deceleration, etc. of the four wheels, to change the vehicle's turning radius, so that the vehicle can be controlled to return to the planned path and continue to track the planned path for driving without replanning a new path. Here, the turning radius when the four-wheel independent motor output torque is combined with the power steering system to control the vehicle's steering is smaller than the turning radius when the vehicle is turned only by the power steering system with the maximum steering wheel angle.

[0069] For example, when compensating for tracking deviation, the remaining required torque for compensating for tracking deviation can be obtained by the torque size corresponding to the maximum steering wheel angle of the vehicle or the torque size corresponding to the current steering wheel angle, and the required torque size of the whole vehicle when the vehicle returns to the planned path; the remaining compensation angle for compensating for tracking deviation can also be obtained according to the maximum steering wheel angle, the current steering wheel angle, and the steering wheel required angle when the vehicle returns to the planned path. When the planned path tracking is achieved only by controlling the steering wheel angle, the remaining required torque or the remaining compensation angle can be 0, and the vehicle steering is controlled only by the power steering system. In order to avoid the body shaking caused by the steering wheel swinging back and forth, the steering wheel angle can be controlled unchanged, and the steering wheel angle can be compensated by the output torque of the four-wheel independent motor. At this time, the steering of the vehicle is controlled by the power steering system combined with the output torque of the four-wheel independent motor. After compensating for the tracking deviation, the vehicle can return to the planned path and continue to drive, so that the vehicle can better track the planned path during driving.

[0070] In the disclosed embodiment, the tracking deviation between the vehicle's position and the vehicle's planned path is determined, and based on the tracking deviation, the output torque of the vehicle's four-wheel independent motors is controlled to make the vehicle return to the planned path. In this way, when the vehicle generates a tracking deviation while following the planned path, the output torque of the four-wheel independent motors can be controlled to make the vehicle return to the planned path, thereby eliminating the need to re-plan a new path and improving the driver's experience.

[0071] As an optional embodiment, according to the tracking deviation, controlling the output torque of the four-wheel independent motors of the vehicle to make the vehicle return to the planned path includes:

[0072] Determine the preview position of the vehicle at a first path point on the planned path;

[0073] According to the first path point and the tracking deviation, the four-wheel independent motors of the vehicle are controlled to output torque so that the vehicle returns to the planned path.

[0074] For example, the preview position of the vehicle can be determined at the first path point on the planned path by previewing, and the required steering wheel angle or the required torque of the whole vehicle required for the vehicle to return to the planned path can be determined based on the first path point and the tracking deviation. The output torque of the four-wheel independent motors is used to compensate for the steering wheel angle or the remaining required torque corresponding to the tracking deviation, so as to compensate for the tracking deviation when the vehicle tracks the planned path.

[0075] As an optional embodiment, the method further includes:

[0076] Get the vehicle speed information;

[0077] Determining a preview position of the vehicle at a first path point on the planned path includes:

[0078] Determining a second path point corresponding to the position of the vehicle on the planned path;

[0079] The first path point is determined according to the second path point and the vehicle speed information.

[0080] For example, the planned path includes a plurality of discrete trajectory points, each of which includes coordinate information, curvature information, vehicle heading angle, speed, distance, etc. The vehicle can determine the second path point corresponding to the position of the vehicle on the planned path according to the posture information, and in a preview manner, according to the preview distance corresponding to the second path point of the vehicle's position on the planned path and the vehicle speed information, can determine the first path point corresponding to the preview position of the vehicle on the planned path, and can control the output torque of the four-wheel independent motor of the vehicle according to the second path point and the steering wheel angle to compensate for the tracking deviation when the vehicle tracks the planned path.

[0081] As an optional embodiment, determining the first path point according to the second path point and the vehicle speed information includes:

[0082] Determine the preview distance based on vehicle speed information;

[0083] The first path point is determined according to the second path point and the preview distance.

[0084] For example, the vehicle speed has a greater impact on the preview distance, wherein the faster the vehicle speed corresponding to the vehicle speed information is, the greater the preview distance is to ensure the safety and stability of the vehicle. In this case, it can be considered that the preview distance is proportional to the vehicle speed information. Specifically, the preview distance can be calculated by the following formula:

[0085] S=v×Δt+d0

[0086] Among them, S is the preview distance, v is the vehicle speed information, Δt is the time factor, and d0 is the minimum preview distance. The specific value of the minimum preview distance can be obtained through calibration or set according to actual conditions, and there is no restriction here.

[0087] As an optional embodiment, Figure 2 As shown, determining the first path point according to the second path point and the preview distance includes:

[0088] S201, determining a preview position on the planned path according to the second path point and the preview distance;

[0089] S202, determining a first trajectory point adjacent to the preview position on the planned path;

[0090] S203, interpolating between the first trajectory points to obtain a plurality of first data points;

[0091] S204: Determine a first path point according to a first data point adjacent to the preview position.

[0092] For example, the preview position of the vehicle can be determined on the planned path through the second path point and the preview distance. The data of the trajectory point on the planned path is known, but the data at the preview position of the vehicle is unknown. If the data of the first trajectory point is directly used to determine the data of the preview position of the vehicle, the error may be large. Therefore, interpolation can be performed between the first trajectory points, and the data corresponding to the interpolated first data point can be calculated based on the data of the first trajectory point. The distance between the interpolated first data point and the preview position of the vehicle is smaller than the distance between the first trajectory point and the preview position of the vehicle. The first data point is used to calculate the data corresponding to the second path point of the preview position of the vehicle on the planned path, and the data of the first path point obtained is more accurate.

[0093] For example, the planned path of the vehicle sometimes has a large curvature change value, such as 0 degrees to 90 degrees. At this time, although the steering wheel angle can meet the demand, the planned path is tracked by quickly adjusting the steering wheel angle, which may cause the steering wheel to swing back and forth. At this time, the vehicle may experience a large shake, affecting the driving experience of the driver and passengers, and tracking deviations may also occur near the curvature mutation point. Therefore, when the curvature information of the planned path represents that the curvature change value of the planned path is greater than or equal to the preset curvature change threshold, the steering wheel angle is controlled to remain unchanged, and the output torque of the four-wheel independent motor of the vehicle is controlled to control the vehicle to follow the planned path. The preset curvature change threshold can be set according to actual conditions and is not limited here. The curvature change value can be determined based on the difference between the curvatures at two adjacent moments. When the curvature change value of the planned path represented by the curvature information is greater than or equal to the preset curvature change threshold, it can be determined that the curvature of the planned path at the vehicle preview position has a sudden change.

[0094] For example, if the curvature on the planned path of the vehicle corresponds to a small turning radius, the requirements may not be met when the vehicle steering is controlled only by the power steering system, resulting in a tracking deviation. Therefore, when the curvature information of the planned path represents that the curvature change value of the planned path is greater than or equal to the preset curvature change threshold, or the turning radius corresponding to the curvature information is less than the turning radius when the vehicle turns at the maximum steering wheel angle, the steering wheel angle can be controlled to be the maximum steering wheel angle, and the output torque of the vehicle's four-wheel independent motors can be controlled to control the vehicle to follow the planned path. When a large tracking deviation occurs, the planned path can be tracked by controlling the vehicle steering by the power steering system combined with the output torque of the four-wheel independent motors.

[0095] In addition, when the vehicle is steered only by the power steering system, the turning radius when the steering wheel is turned at the maximum angle can be called the minimum turning radius. When the turning radius corresponding to the curvature information of the planned path is greater than or equal to the minimum turning radius, the vehicle can be controlled to track the planned path only by the power steering system, or the power steering system can be combined with the four-wheel independent motor output torque to control the vehicle steering to track the planned path; when the turning radius corresponding to the curvature information of the planned path is less than the minimum turning radius, the vehicle can be controlled to travel along the planned path by combining the power steering system with the four-wheel independent motor output torque to control the vehicle steering.

[0096] As an optional embodiment, determining a tracking deviation between a position of the vehicle and a planned path of the vehicle includes:

[0097] Determine reference data points adjacent to the vehicle's position on the planned path;

[0098] The tracking deviation is determined based on the posture information corresponding to the vehicle's position and the reference data points.

[0099] For example, when a vehicle follows a planned path, the path points of the vehicle may deviate from the planned path, resulting in tracking deviation. The vehicle's position is projected onto the planned path. The vehicle's position may not be on the driving trajectory corresponding to the planned path, but on the outside of the driving trajectory, and the reference point is located on the driving trajectory corresponding to the planned path. Therefore, after determining the reference data points adjacent to the vehicle's position, the tracking deviation of the vehicle's position when the vehicle tracks the planned path can be determined based on the reference data points and the vehicle's posture information, thereby controlling the output torque of the vehicle's four-wheel independent motors to compensate for the tracking deviation when the vehicle tracks the planned path, so that the vehicle returns to the planned path.

[0100] As an optional embodiment, Figure 3 As shown, the reference data points adjacent to the vehicle's position are determined on the planned path, including:

[0101] S301, determining a second trajectory point adjacent to the position of the vehicle on the planned path;

[0102] S302, interpolating between the second trajectory points to obtain a plurality of second data points;

[0103] S303: Determine, from among the plurality of second data points, a data point whose distance from the position of the vehicle is less than or equal to a distance threshold as a reference data point.

[0104] For example, the planned path includes multiple discrete trajectory points, each of which contains coordinate information, curvature information, vehicle heading angle, speed, distance and other information. According to the posture information corresponding to the position of the vehicle, the second trajectory point adjacent to the position of the vehicle on the planned path can be determined. The data of the second trajectory point on the planned path is known, but the data of the position of the vehicle is unknown. If the data of the second trajectory point is directly used as the reference data point, the error of the calculated tracking deviation may be large. Therefore, interpolation can be performed between the second trajectory points, and the data corresponding to the interpolated second data point can be calculated based on the data of the second trajectory point. A linear interpolation method can be used. Determine the data point whose distance from the first path point is less than or equal to the distance threshold among the multiple second data points as the reference data point, and the data point closest to the first path point among the multiple second data points can also be used as the reference data point, or the data average of multiple data points whose distance from the first path point is less than or equal to the distance threshold can be determined as the data of the reference data point.

[0105] After step S303, the method may further include:

[0106] S304: Determine the tracking deviation according to the vehicle posture information and the information of the reference data point.

[0107] For example, the tracking deviation may include a lateral error and a heading error. The lateral error and the heading error may be determined based on the first coordinate of the vehicle posture information on the planned path and the second coordinate of the reference data point on the planned path. After obtaining the heading error and the lateral error, the turning angle to be compensated corresponding to the vehicle tracking deviation may be determined. Specifically, if the first coordinate is expressed as (x v ,y v ,θ v ), the second coordinate is expressed as (x r ,y r ,θ r ), the lateral error and heading error can be calculated by the following formula:

[0108]

[0109] Among them, Δθ is the heading error, Δσ is the lateral error, and θ v is the vehicle heading angle, θ r is the curvature of the reference data point, x v is the X-axis coordinate data of the first path point on the planned path, y v is the Y-axis coordinate data of the first path point on the planned path, x r is the X-axis coordinate data of the reference data point on the planned path, y r It is the Y-axis coordinate data of the reference data point on the planned path.

[0110] As an optional embodiment, according to the tracking deviation, controlling the output torque of the four-wheel independent motors of the vehicle to make the vehicle return to the planned path includes:

[0111] Determine the required steering wheel angle required for the vehicle to return to the planned path based on the tracking deviation;

[0112] According to the required steering wheel angle, the steering wheel angle is controlled, and the output torque of the four-wheel independent motor is controlled so that the sum of the steering wheel angle and the compensation angle corresponding to the output torque of the four-wheel independent motor meets the required steering wheel angle.

[0113] For example, the steering wheel angle is the steering wheel angular displacement measured based on the position of the steering wheel when the vehicle is moving straight, wherein, for a vehicle that controls steering only through a power steering system, the steering wheel is the front wheel, and the average steering angle of the left and right steering wheels is zero when the vehicle is moving straight. The maximum angle of the steering wheel turning from the reference position to one side is generally 540-630 degrees, corresponding to a maximum steering angle of the wheel of about 40-42 degrees. The steering wheel angle can be obtained by a steering wheel angle sensor, which is installed in the steering column below the steering wheel and can be divided into an analog steering wheel angle sensor and a digital steering wheel angle sensor. The required steering wheel angle is obtained based on the steering wheel angle when the vehicle is driving and the angle to be compensated corresponding to the tracking deviation, so as to obtain the required steering wheel angle required for the vehicle to return to the planned path. The output torque of the four-wheel independent motor is controlled, and the compensation angle corresponding to the magnitude of the output torque can be used to compensate for the angle to be compensated.

[0114] As an optional embodiment, according to the required steering wheel angle, the steering wheel angle is controlled, and the output torque of the four-wheel independent motors is controlled, including:

[0115] According to the required steering wheel angle, the steering wheel angle is controlled to remain unchanged, and the difference between the steering wheel angle and the required steering wheel angle is determined as the angle to be compensated;

[0116] The four-wheel independent motors are controlled to output torque to compensate the steering angle to be compensated.

[0117] For example, by adjusting the steering wheel angle to track the planned path, this may cause the steering wheel to swing back and forth, resulting in greater vehicle shaking, affecting the driving experience of the driver and passengers. Therefore, when controlling the output torque of the four-wheel independent motor, the steering wheel angle can be controlled to remain unchanged, and the output torque of the vehicle's four-wheel independent motor can be controlled to compensate for the angle to be compensated, so that the vehicle can be controlled to return to the planned path and continue driving.

[0118] The present disclosure does not change the steering wheel angle, but compensates the angle to be compensated corresponding to the tracking deviation by using the torque output of the four-wheel independent motors. The angle to be compensated can be the difference between the steering wheel angle and the required steering wheel angle. In this way, after compensating the tracking deviation, the vehicle can return to the planned path and continue driving, so that the vehicle can more accurately track the planned path for driving, reduce the swing of the steering wheel due to external disturbances, and improve the driver's driving experience.

[0119] As an optional embodiment, according to the required steering wheel angle, the steering wheel angle is controlled, and the output torque of the four-wheel independent motors is controlled, including:

[0120] When the required steering wheel angle is less than or equal to the maximum steering wheel angle, the steering wheel angle is controlled to be gradually increased according to the required steering wheel angle, and the output torque of the four-wheel independent motor is controlled to compensate for the difference between the increased steering wheel angle and the required steering wheel angle;

[0121] When the required steering wheel angle is greater than the maximum steering wheel angle, the steering wheel angle is controlled to increase to the maximum steering wheel angle, and the four-wheel independent motor output torque is controlled to compensate for the difference between the maximum steering wheel angle and the required steering wheel angle.

[0122] For example, when the required steering wheel angle is less than or equal to the maximum steering wheel angle, the steering of the vehicle can be controlled by the power steering system combined with the output torque of the four-wheel independent motor to control the steering of the vehicle, so as to control the steering wheel angle to change smoothly, and the steering wheel angle can be compensated by controlling the output torque of the four-wheel independent motor to meet the required steering wheel angle of the vehicle. In this process, if the required steering wheel angle is less than or equal to the maximum steering wheel angle, the torque output by the four-wheel independent motor first increases and then gradually decreases. When the steering wheel angle reaches the target angle, the torque output by the four-wheel independent motor decreases to 0; if the required steering wheel angle is greater than the maximum steering wheel angle, the torque output by the four-wheel independent motor first increases and then gradually decreases to the first target value; if the required steering wheel angle is greater than the maximum steering wheel angle and the current steering wheel angle is equal to the maximum steering wheel angle, the torque output by the four-wheel independent motor gradually increases to the second target value.

[0123] For example, when the required steering wheel angle is greater than the maximum steering wheel angle, the steering wheel angle is controlled to increase to the maximum steering wheel angle, and the four-wheel independent motor output torque is controlled to compensate for the difference between the maximum steering wheel angle and the required steering wheel angle. The steering wheel angle can also be controlled to remain unchanged, and the steering wheel angle can be compensated by controlling the output torque of the four-wheel independent motor to meet the required steering wheel angle. When the steering wheel angle is controlled to increase to the maximum steering wheel angle, the steering wheel angle can be directly controlled to be the maximum steering wheel angle, or the steering wheel angle can be controlled to gradually increase to the maximum steering wheel angle, and the four-wheel independent motor output torque can be controlled.

[0124] As an optional embodiment, the method further includes:

[0125] Obtain the vehicle's position information, parking space information around the vehicle, and obstacle information;

[0126] Trajectory planning is performed based on the posture information, parking space information, obstacle information, and the target turning radius when the vehicle is driven by four-wheel independent motors to obtain a planned path, wherein the target turning radius is smaller than the turning radius when the vehicle turns at the maximum steering wheel angle.

[0127] For example, the vehicle's position information can be obtained in real time through the RTK (Real-time kinematic, real-time differential positioning) high-precision positioning device on the vehicle. When the vehicle plans a driving route, the planning method of the planned driving route is determined based on the parking space information, obstacle information and the current vehicle position. Specifically, a geometric planning algorithm can be used. The vehicle includes four-wheel independent motors. When planning the route, the target turning radius of the vehicle when driven by the four-wheel independent motor can be considered for planning. The trajectory radius cannot be lower than the target turning radius. The target turning radius is determined by the power steering system combined with the output torque of the four-wheel independent motor to control the vehicle steering, wherein the target turning radius is smaller than the turning radius when the vehicle is controlled by the power steering system to turn at the maximum steering wheel angle.

[0128] For example, Figure 4 As shown, the method for determining the target turning radius includes:

[0129] S401. Test the minimum turning radius of the vehicle controlled by the power steering system.

[0130] For example, in an open and flat area, the power steering system can be used to control the vehicle to idle for one circle with the steering wheel at the maximum angle, and the vehicle position information on the high-precision positioning device RTK can be read.

[0131] S402. Test the turning radius when the power steering system is used to control the steering wheel to the maximum turning angle and the four-wheel independent motors output the maximum torque to control the vehicle steering.

[0132] For example, in an open and flat area, the four-wheel independent motors can be controlled to apply maximum torque, and the vehicle can be controlled to idle for one circle with the maximum steering wheel angle, and the vehicle position information on the high-precision positioning device RTK can be read.

[0133] S403, after executing step S401 and step S402 multiple times, multiple vehicle position information is obtained, and a target turning radius of the planned path is calculated according to the vehicle position information using a least squares algorithm.

[0134] As an optional embodiment, determining a second path point corresponding to the position of the vehicle on the planned path includes:

[0135] Obtain vehicle position information and plan path;

[0136] According to the position information, a second path point corresponding to the position of the vehicle is determined on the planned path.

[0137] For example, based on the vehicle's posture information and planned path, a second path point on the planned path corresponding to the vehicle's position can be determined, so that the vehicle's four-wheel independent motor output torque can be controlled according to the second path point and the steering wheel angle to compensate for the tracking deviation when the vehicle follows the planned path, so that the vehicle returns to the planned path and continues to drive.

[0138] See also Figure 5 , Figure 5 is a block diagram of a vehicle control device according to an exemplary embodiment. Figure 5 As shown, the vehicle control device 500 includes a determination module 501 and a control module 502 .

[0139] A determination module 502 is configured to determine a tracking deviation between a position of the vehicle and a planned path of the vehicle;

[0140] The control module 502 is configured to control the output torque of the four-wheel independent motors of the vehicle according to the tracking deviation, so as to make the vehicle return to the planned path.

[0141] As an optional embodiment, the control module 502 includes:

[0142] A first determination submodule is configured to determine a first path point of a preview position of the vehicle on a planned path;

[0143] The control submodule is configured to control the output torque of the four-wheel independent motors of the vehicle according to the first path point and the tracking deviation so as to make the vehicle return to the planned path.

[0144] As an optional embodiment, the vehicle control device 500 further includes:

[0145] An acquisition module is configured to acquire vehicle speed information of the vehicle;

[0146] The first determination submodule includes:

[0147] A second determination submodule is configured to determine a second path point corresponding to the position of the vehicle on the planned path;

[0148] The third determination submodule is configured to determine the first path point according to the second path point and the vehicle speed information.

[0149] As an optional embodiment, the third determining submodule includes:

[0150] The fourth determination submodule is configured to determine the preview distance according to the vehicle speed information;

[0151] The fifth determination submodule is configured to determine the first path point according to the second path point and the preview distance.

[0152] As an optional embodiment, the fifth determining submodule is configured as follows:

[0153] Determine the preview position on the planned path according to the second path point and the preview distance;

[0154] Determining a first trajectory point adjacent to the preview position on the planned path;

[0155] interpolating between the first trajectory points to obtain a plurality of first data points;

[0156] A first path point is determined based on a first data point adjacent to the preview position.

[0157] As an optional embodiment, the determining module 501 includes:

[0158] a sixth determination submodule, configured to determine a reference data point adjacent to the position of the vehicle on the planned path;

[0159] The seventh determination submodule is configured to determine the tracking deviation according to the posture information corresponding to the position of the vehicle and the reference data points.

[0160] As an optional embodiment, the sixth determining submodule is specifically configured as follows:

[0161] Determining a second trajectory point adjacent to the position of the vehicle on the planned path;

[0162] interpolating between the second trajectory points to obtain a plurality of second data points;

[0163] A data point whose distance from the position of the vehicle is less than or equal to a distance threshold is determined from the plurality of second data points as a reference data point.

[0164] As an optional embodiment, the control module 502 includes:

[0165] A demand determination module is configured to determine a required steering wheel angle required for the vehicle to return to the planned path based on the tracking deviation;

[0166] The demand compensation module is configured to control the steering wheel angle according to the required steering wheel angle, and control the output torque of the four-wheel independent motor so that the sum of the steering wheel angle and the compensation angle corresponding to the output torque of the four-wheel independent motor meets the required steering wheel angle.

[0167] As an optional embodiment, the demand compensation module is specifically configured as follows:

[0168] According to the required steering wheel angle, the steering wheel angle is controlled to remain unchanged, and the difference between the steering wheel angle and the required steering wheel angle is determined as the angle to be compensated;

[0169] The four-wheel independent motors are controlled to output torque to compensate the steering angle to be compensated.

[0170] As an optional embodiment, the demand compensation module is specifically configured as follows:

[0171] When the required steering wheel angle is less than or equal to the maximum steering wheel angle, the steering wheel angle is controlled to be gradually increased according to the required steering wheel angle, and the output torque of the four-wheel independent motor is controlled to compensate for the difference between the increased steering wheel angle and the required steering wheel angle;

[0172] When the required steering wheel angle is greater than the maximum steering wheel angle, the steering wheel angle is controlled to increase to the maximum steering wheel angle, and the four-wheel independent motor output torque is controlled to compensate for the difference between the maximum steering wheel angle and the required steering wheel angle.

[0173] As an optional embodiment, the vehicle control device 500 includes:

[0174] An information acquisition module is configured to acquire the position information of the vehicle, the parking space information around the vehicle, and the obstacle information;

[0175] The planning module is configured to perform trajectory planning based on the posture information, parking space information, obstacle information, and a target turning radius when the vehicle is driven by four-wheel independent motors to obtain a planned path, wherein the target turning radius is smaller than a turning radius when the vehicle turns at a maximum steering wheel angle.

[0176] As an optional embodiment, the second determining submodule is specifically configured as follows:

[0177] Obtain vehicle position information and plan path;

[0178] According to the position information, a second path point corresponding to the position of the vehicle is determined on the planned path.

[0179] Regarding the vehicle control device 500 in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the vehicle control method, and will not be elaborated here.

[0180] See also Figure 6 , Figure 6 is a block diagram of a vehicle control system according to an exemplary embodiment. Figure 6 As shown, the vehicle control system 600 includes a vehicle control device 500 , a parking space sensing module 610 , an obstacle sensing module 620 , a positioning module 630 , a planning module 640 and a steering wheel angle detection module 650 .

[0181] The parking space sensing module 610 is used to detect parking space information around the vehicle;

[0182] The obstacle sensing module 620 is used to detect obstacle information around the vehicle;

[0183] The positioning module 630 is used to detect the position information of the vehicle;

[0184] The planning module 640 is connected to the parking space sensing module 610, the obstacle sensing module 620 and the positioning module 630, and is used to perform trajectory planning according to the parking space information, obstacle information and posture information to obtain a planned path;

[0185] The steering wheel angle detection module 650 is used to detect the steering wheel angle;

[0186] The vehicle control device 500 is connected to the planning module 640, the positioning module 630 and the steering wheel angle detection module 650, and is used to determine the tracking deviation between the vehicle's position and the vehicle's planned path, and control the output torque of the vehicle's four-wheel independent motors based on the tracking deviation to make the vehicle return to the planned path.

[0187] Among them, the control module 502 of the vehicle control device 500 is connected to the four-wheel independent motor control module 5021 and the power steering control module 5022. The four-wheel independent motor control module 5021 is used to control the output torque of the four-wheel independent motor based on the motor control instruction of the control module 502. The power steering control module 5022 is used to control the size of the steering wheel angle based on the steering wheel angle control instruction of the control module 502. Through the four-wheel independent motor control module 5021 and the power steering control module 5022, the output torque of the four-wheel independent motor of the vehicle can be controlled according to the tracking deviation so that the vehicle can return to the planned path.

[0188] The present disclosure also provides a computer-readable storage medium having computer program instructions stored thereon, and the vehicle control method of the present disclosure is implemented when the program instructions are executed by a processor.

[0189] The present disclosure also provides a vehicle, the vehicle comprising:

[0190] a storage device, wherein the storage device stores a computer program;

[0191] A control device is used to execute a computer program to implement the vehicle control method disclosed herein.

[0192] As an optional embodiment, the vehicle includes four motors, each motor driving a corresponding wheel.

[0193] Figure 7is a block diagram of a vehicle 700 according to an exemplary embodiment. For example, the vehicle 700 may be a hybrid vehicle, a non-hybrid vehicle, an electric vehicle, a fuel cell vehicle, or other types of vehicles. The vehicle 700 may be an autonomous vehicle, or a semi-autonomous vehicle.

[0194] Reference Figure 7 , the vehicle 700 may include various subsystems, for example, an infotainment system 710, a perception system 720, a decision control system 730, a drive system 740, and a computing platform 750. The vehicle 700 may also include more or fewer subsystems, and each subsystem may include multiple components. In addition, each subsystem and each component of the vehicle 700 may be interconnected by wire or wireless means.

[0195] In some embodiments, the infotainment system 710 may include a communication system, an entertainment system, and a navigation system, etc.

[0196] The perception system 720 may include several sensors for sensing information about the environment around the vehicle 700. For example, the perception system 720 may include a global positioning system (the global positioning system may be a GPS system, or a Beidou system or other positioning systems), an inertial measurement unit (IMU), a laser radar, a millimeter wave radar, an ultrasonic radar, and a camera.

[0197] The decision control system 730 may include a computing system, a vehicle controller, a steering system, a throttle, and a braking system.

[0198] The drive system 740 may include components that provide powered motion for the vehicle 700. In one embodiment, the drive system 740 may include an engine, an energy source, a vehicle control system 600, and wheels. The engine may be a combination of one or more of an internal combustion engine, an electric motor, and an air compression engine. The engine is capable of converting energy provided by the energy source into mechanical energy.

[0199] Some or all functions of the vehicle 700 are controlled by a computing platform 750. The computing platform 750 may include at least one processor 751 and a memory 752, and the processor 751 may execute instructions 753 stored in the memory 752.

[0200] The processor 751 may be any conventional processor, such as a commercially available CPU. The processor may also include a graphics processor (Graphic Process Unit, GPU), a field programmable gate array (Field Programmable Gate Array, FPGA), a system on chip (System on Chip, SOC), an application specific integrated circuit (Application Specific Integrated Circuit, ASIC) or a combination thereof.

[0201] Memory 752 can be implemented by any type of volatile or nonvolatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0202] In addition to instructions 753 , memory 752 may also store data, such as road maps, route information, vehicle location, direction, speed, etc. The data stored in memory 752 may be used by computing platform 750 .

[0203] In the embodiment of the present disclosure, the processor 751 can execute instruction 753 to complete all or part of the steps of the above-mentioned vehicle control method.

[0204] In another exemplary embodiment, a computer program product is also provided. The computer program product includes a computer program executable by a programmable device. The computer program has a code portion for executing the above-mentioned vehicle control method when executed by the programmable device.

[0205] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the present disclosure. This application is intended to cover any variations, uses or adaptations of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary technical means in the art that are not disclosed in the present disclosure. The specification and examples are to be considered as exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims.

[0206] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A vehicle control method, characterized in that: include: Determining a tracking deviation between the position of the vehicle and a planned path of the vehicle; According to the tracking deviation, the four-wheel independent motors of the vehicle are controlled to output torque so as to return the vehicle to the planned path.

2. The method according to claim 1, characterized in that: According to the tracking deviation, controlling the output torque of the four-wheel independent motors of the vehicle to return the vehicle to the planned path includes: Determine a first path point of the preview position of the vehicle on the planned path; According to the first path point and the tracking deviation, the four-wheel independent motors of the vehicle are controlled to output torque so that the vehicle returns to the planned path.

3. The method according to claim 2, characterized in that The method further comprises: Obtaining speed information of the vehicle; Determining a first path point of the preview position of the vehicle on the planned path includes: Determining a second path point corresponding to the position of the vehicle on the planned path; The first path point is determined according to the second path point and the vehicle speed information.

4. The method according to claim 3, characterized in that Determining the first path point according to the second path point and the vehicle speed information includes: Determining a preview distance according to the vehicle speed information; Determine the first path point according to the second path point and the preview distance.

5. The method according to claim 4, characterized in that Determining the first path point according to the second path point and the preview distance includes: Determining the preview position on the planned path according to the second path point and the preview distance; Determining a first trajectory point adjacent to the preview position on the planned path; interpolating between the first trajectory points to obtain a plurality of first data points; The first path point is determined based on a first data point adjacent to the preview position.

6. The method according to claim 1, characterized in that Determining a tracking deviation between the position of the vehicle and a planned path of the vehicle includes: Determining a reference data point adjacent to the position of the vehicle on the planned path; The tracking deviation is determined according to the posture information corresponding to the position of the vehicle and the reference data point.

7. The method according to claim 6, characterized in that Determining a reference data point adjacent to the position of the vehicle on the planned path includes: Determining a second trajectory point adjacent to the position of the vehicle on the planned path; interpolating between the second trajectory points to obtain a plurality of second data points; A data point whose distance from the position of the vehicle is less than or equal to a distance threshold is determined among the plurality of second data points as the reference data point.

8. The method according to any one of claims 1 to 7, characterized in that: According to the tracking deviation, controlling the output torque of the four-wheel independent motors of the vehicle to return the vehicle to the planned path includes: Determining a required steering wheel angle required for the vehicle to return to the planned path according to the tracking deviation; According to the required steering wheel angle, the steering wheel angle is controlled, and the output torque of the four-wheel independent motor is controlled so that the sum of the steering wheel angle and the compensation angle corresponding to the output torque of the four-wheel independent motor meets the required steering wheel angle.

9. The method according to claim 8, characterized in that According to the required steering wheel angle, the steering wheel angle is controlled, and the output torque of the four-wheel independent motors is controlled, including: According to the required steering wheel angle, controlling the steering wheel angle to remain unchanged, and determining the difference between the steering wheel angle and the required steering wheel angle as the angle to be compensated; The four-wheel independent motors are controlled to output torque to compensate for the turning angle to be compensated.

10. The method according to claim 8, characterized in that According to the required steering wheel angle, the steering wheel angle is controlled, and the output torque of the four-wheel independent motors is controlled, including: When the required steering wheel angle is less than or equal to the maximum steering wheel angle, the steering wheel angle is controlled to be gradually increased according to the required steering wheel angle, and the four-wheel independent motors are controlled to output torque to compensate for the difference between the increased steering wheel angle and the required steering wheel angle; When the required steering wheel angle is greater than the maximum steering wheel angle, the steering wheel angle is controlled to increase to the maximum steering wheel angle, and the four-wheel independent motors are controlled to output torque to compensate for the difference between the maximum steering wheel angle and the required steering wheel angle.

11. The method according to any one of claims 1 to 7, characterized in that: The method further comprises: Acquire the position information of the vehicle, the parking space information and the obstacle information around the vehicle; Trajectory planning is performed according to the posture information, the parking space information, the obstacle information, and a target turning radius when the vehicle is driven by four-wheel independent motors to obtain the planned path, wherein the target turning radius is smaller than a turning radius when the vehicle turns at a maximum steering wheel angle.

12. The method according to any one of claims 3 to 5, characterized in that: Determining a second path point corresponding to the position of the vehicle on the planned path includes: Obtaining the position information and planned path of the vehicle; According to the position information, a second path point corresponding to the position of the vehicle is determined on the planned path.

13. A computer-readable storage medium having computer program instructions stored thereon, characterized in that: When the program instructions are executed by a processor, the vehicle control method described in any one of claims 1-12 is implemented.

14. A vehicle, characterized in that: include: A storage device for storing a computer program; A processing device, used to execute the computer program to implement the vehicle control method described in any one of claims 1-12.

15. The vehicle according to claim 14, characterized in that The vehicle includes four motors, each of which drives a corresponding wheel.

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