An Automatic Parking Trajectory Tracking Method, System, and Computer Readable Storage Medium

Abstract

The present invention discloses an automatic parking trajectory tracking method, system, and computer-readable storage medium, including: obtaining a parking trajectory planning segment; obtaining the current vehicle speed and the current vehicle gear position, and determining a current preview distance according to the current vehicle speed and the current vehicle gear position; obtaining the current vehicle position; determining the current preview tracking point position according to the parking trajectory planning segment, the current preview distance, and the current vehicle position; obtaining the current vehicle heading angle; determining the current front wheel steering angle according to the current vehicle position, the current vehicle heading angle, the current preview distance, and the current preview tracking point position; and determining the current steering wheel steering angle according to the current front wheel steering angle. By means of the present invention, the calculation amount of the tracking control algorithm can be reduced, and the performance requirements of the algorithm for the hardware can be lowered.

Description

Technical Field

[0001] The present invention relates to the technical field of automatic parking, and particularly to an automatic parking trajectory tracking method and system, and a computer-readable storage medium. Background Art

[0002] Automatic parking is an important auxiliary function of advanced driver assistance. During the automatic parking process of a vehicle, automatic parking trajectory tracking is required. Some existing automatic parking trajectory tracking algorithms have a large amount of calculation and high requirements for hardware. For example, the preview distance is determined according to the vehicle speed, the discrete point sequence of the desired path in the earth coordinate system is converted into discrete points in the vehicle coordinate system, then the trajectory tracking points are determined according to the difference between the preview distance and the target distance, and then the front wheel angle of the vehicle is calculated according to the lateral displacement error between the vehicle centroid and the trajectory tracking points. In this method, the calculation of the discrete points of the desired path is already computationally intensive, and the data is large and occupies memory. Coupled with coordinate transformation and then finding the tracking points, the algorithm has a large amount of calculation and high performance requirements for hardware. Summary of the Invention

[0003] The purpose of the present invention is to provide an automatic parking trajectory tracking method and system, and a computer-readable storage medium, so as to reduce the calculation amount of the tracking control algorithm and reduce the performance requirements of the algorithm for hardware.

[0004] To achieve the above purpose, the first aspect of the present invention provides an automatic parking trajectory tracking method, including:

[0005] Obtain the current vehicle speed and the current vehicle gear, and determine the current preview distance according to the current vehicle speed and the current vehicle gear;

[0006] Obtain the parking trajectory planning section and the current vehicle position, and determine the current preview tracking point position according to the parking trajectory planning section, the current preview distance and the current vehicle position;

[0007] Obtain the current vehicle heading angle, and determine the current front wheel angle according to the current vehicle position, the current vehicle heading angle, the current preview distance and the current preview tracking point position;

[0008] Determine the current steering wheel angle according to the current front wheel angle.

[0009] Optionally, the determining the current preview distance according to the current vehicle speed and the current vehicle gear includes:

[0010] If the current vehicle gear is the forward gear, the current preview distance L is:

[0011] L = K×V + L min ;

[0012] If the current vehicle gear is in reverse gear, the current preview distance L is:

[0013] L = -K × V – L min ;

[0014] And, |L| is less than or equal to the preset L max ;

[0015] Where, K is a preset coefficient, V is the current vehicle speed, L min is the preset minimum sight distance, L max is the preset maximum sight distance.

[0016] Optionally, the determining the current preview tracking point position according to the parking trajectory planning segment, the current preview distance, and the current vehicle position includes:

[0017] Determine whether the change in the abscissa between the starting point and the ending point of the parking trajectory planning segment is greater than the change in the ordinate;

[0018] If so, the initial abscissa of the current preview tracking point is equal to the abscissa of the current vehicle position plus the current preview distance, and the abscissa and ordinate of the current preview tracking point position are determined according to the positional relationship between the initial abscissa and the parking trajectory planning segment;

[0019] If not, the initial ordinate of the current preview tracking point is equal to the ordinate of the current vehicle position plus the current preview distance, and the abscissa and ordinate of the current preview tracking point position are determined according to the positional relationship between the initial ordinate and the parking trajectory planning segment.

[0020] Optionally, wherein, the determining the abscissa and ordinate of the current preview tracking point position according to the positional relationship between the initial abscissa and the parking trajectory planning segment specifically includes: if the initial abscissa is greater than the abscissa of the ending point of the parking trajectory planning segment, the abscissa and ordinate of the current preview tracking point position are determined to be the abscissa and ordinate of the ending point of the parking trajectory planning segment; if the initial abscissa is less than the abscissa of the starting point of the parking trajectory planning segment, the abscissa and ordinate of the current preview tracking point position are determined to be the abscissa and ordinate of the starting point of the parking trajectory planning segment;

[0021] Wherein, the determining the abscissa and ordinate of the current preview tracking point position according to the positional relationship between the initial ordinate and the parking trajectory planning segment specifically includes: if the initial ordinate is greater than the ordinate of the ending point of the parking trajectory planning segment, the abscissa and ordinate of the current preview tracking point position are determined to be the abscissa and ordinate of the ending point of the parking trajectory planning segment; if the initial ordinate is less than the ordinate of the starting point of the parking trajectory planning segment, the abscissa and ordinate of the current preview tracking point position are determined to be the abscissa and ordinate of the starting point of the parking trajectory planning segment.

[0022] Optionally, if the parking trajectory planning segment is an arc, the horizontal and vertical coordinates of the current preview tracking point position determined according to the positional relationship between the initial abscissa and the parking trajectory planning segment specifically include: if the initial abscissa is greater than or equal to the abscissa of the arc starting point and less than or equal to the abscissa of the arc ending point, then determine the initial abscissa as the horizontal coordinate of the current preview tracking point position, and determine the vertical coordinate of the current preview tracking point position according to the center coordinates and radius of the arc;

[0023] And, the horizontal and vertical coordinates of the current preview tracking point position determined according to the positional relationship between the initial ordinate and the parking trajectory planning segment specifically include: if the initial ordinate is greater than or equal to the ordinate of the arc starting point and less than or equal to the ordinate of the arc ending point, then determine the initial ordinate as the vertical coordinate of the current preview tracking point position, and determine the horizontal coordinate of the current preview tracking point position according to the center coordinates and radius of the arc.

[0024] Optionally, if the parking trajectory planning segment is a straight line, the horizontal and vertical coordinates of the current preview tracking point position determined according to the positional relationship between the initial abscissa and the parking trajectory planning segment specifically include: if the initial abscissa is greater than or equal to the abscissa of the straight line starting point and less than or equal to the abscissa of the straight line ending point, then determine the initial abscissa as the horizontal coordinate of the current preview tracking point position, and determine the vertical coordinate of the current preview tracking point position according to the straight line equation corresponding to the straight line and the initial abscissa;

[0025] And, the horizontal and vertical coordinates of the current preview tracking point position determined according to the positional relationship between the initial ordinate and the parking trajectory planning segment specifically include: if the initial ordinate is greater than or equal to the ordinate of the straight line starting point and less than or equal to the ordinate of the straight line ending point, then determine the initial ordinate as the vertical coordinate of the current preview tracking point position, and determine the horizontal coordinate of the current preview tracking point position according to the straight line equation corresponding to the straight line and the initial ordinate.

[0026] Optionally, determining the current front wheel steering angle according to the current vehicle position, the current vehicle heading angle, the current preview distance, and the current preview tracking point position includes:

[0027] Specifically, calculate and determine the current front wheel steering angle according to the following formula;

[0028]

[0029]

[0030] Where, δ is the current front wheel steering angle, l is the given wheelbase of the vehicle, L is the current preview distance, Ax is the abscissa of the current vehicle position, Ay is the ordinate of the current vehicle position, Bx is the abscissa of the current preview tracking point position, By is the ordinate of the current preview tracking point position, and yaw is the current vehicle heading angle.

[0031] Optionally, determining the current steering wheel angle according to the current front wheel steering angle includes:

[0032] Specifically, calculate and determine the current steering wheel angle according to the following formula;

[0033] θ = kδ + b

[0034] Where, θ is the current steering wheel angle, k is the preset linear fitting coefficient, δ is the current front wheel steering angle, and b is the preset linear fitting offset constant.

[0035] A second aspect of the present invention proposes an automatic parking trajectory tracking system for implementing the automatic parking trajectory tracking method described in the first aspect. The system includes:

[0036] A preview distance determination unit for obtaining the current vehicle speed and the current vehicle gear, and determining the current preview distance according to the current vehicle speed and the current vehicle gear;

[0037] A preview tracking point determination unit for obtaining the parking trajectory planning section and the current vehicle position, and determining the current preview tracking point position according to the parking trajectory planning section, the current preview distance, and the current vehicle position;

[0038] A front wheel steering angle determination unit for determining the current front wheel steering angle according to the current vehicle position, the current vehicle heading angle, the current preview distance, and the current preview tracking point position; and

[0039] A steering wheel angle determination unit for determining the current steering wheel angle according to the current front wheel steering angle.

[0040] A third aspect of the present invention proposes a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the automatic parking trajectory tracking method described in the first aspect.

[0041] In summary, an embodiment of the present invention provides an automatic parking trajectory tracking method, system, and computer-readable storage medium, including determining a current preview distance according to the current vehicle speed and the current vehicle gear; determining the position of the current preview tracking point according to the parking trajectory planning segment, the current preview distance, and the current vehicle position; determining the current front wheel steering angle according to the current vehicle position, the current vehicle heading angle, the current preview distance, and the position of the current preview tracking point; and finally, determining the current steering wheel steering angle according to the current front wheel steering angle. When performing automatic parking trajectory tracking, the preview tracking point in the embodiment of the present invention is dynamically calculated based on the real-time position of the vehicle, without the need for a preview sequence of points. Instead, the planned path and the real-time position information of the vehicle in the earth coordinate system are directly used. Compared with the traditional method of converting the discrete point sequence of the desired path in the earth coordinate system into the discrete points in the vehicle coordinate system and then determining the trajectory tracking point according to the difference between the preview distance and the target distance, the cumbersome operation of coordinate conversion is eliminated, the preview sequence of points is not required, the computational amount of the tracking control algorithm can be reduced, the CPU memory space can be saved, and the performance requirements of the algorithm for the hardware can be reduced.

[0042] Other features and advantages of the present invention will be described in the following specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0044] Figure 1 It is a flowchart of an automatic parking trajectory tracking method in an embodiment of the present invention.

[0045] Figure 2 It is a schematic structural diagram of an automatic parking trajectory tracking system in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0046] The following will describe various exemplary embodiments, features, and aspects of the present disclosure in detail with reference to the drawings. In addition, in order to better illustrate the present invention, numerous specific details are given in the following detailed embodiments. Those skilled in the art should understand that the present invention can be implemented without some of these specific details. In some instances, well-known means have not been described in detail to highlight the gist of the present invention.

[0047] Refer to Figure 1 , an embodiment of the present invention provides an automatic parking trajectory tracking method, including the following steps S1 to S4:

[0048] Step S1: Obtain the current vehicle speed and the current vehicle gear, and determine the current preview distance according to the current vehicle speed and the current vehicle gear;

[0049] Exemplarily, the determining the current preview distance according to the current vehicle speed and the current vehicle gear includes:

[0050] If the current vehicle gear is the forward gear, the current preview distance L is:

[0051] L = K×V + L min ;

[0052] If the current vehicle gear is the reverse gear, the current preview distance L is:

[0053] L = -K×V – L min ;

[0054] And, |L| is less than or equal to the preset L max ;

[0055] Wherein, K is a preset coefficient, V is the current vehicle speed, and L min is the preset minimum viewing distance, and L max is the preset maximum viewing distance;

[0056] Specifically, the vehicle speed V obtained in this embodiment is a scalar. Therefore, in this embodiment, the vehicle gear is used to determine the direction of the preview distance. In this embodiment, the absolute value of the preview distance L is limited to prevent the preview distance L from exceeding the set range;

[0057] Step S2: Obtain the parking trajectory planning section and the current vehicle position, and determine the current preview tracking point position according to the parking trajectory planning section, the current preview distance, and the current vehicle position;

[0058] Exemplarily, assume that the current vehicle position is point A in the earth coordinate system, the current preview tracking point position is point B in the earth coordinate system, the starting point of the parking trajectory planning section is Q in the earth coordinate system, and the end point is Z in the earth coordinate system;

[0059] Then, the determining the current preview tracking point position according to the parking trajectory planning section, the current preview distance, and the current vehicle position includes:

[0060] Step S21: Determine whether the change in the abscissa between the starting point Q and the end point Z of the parking trajectory planning section is greater than the change in the ordinate;

[0061] Specifically, the change in the abscissa is the absolute value of the difference between the abscissas of the starting point Q and the end point Z, and the change in the ordinate is the absolute value of the difference between the ordinates of the starting point Q and the end point Z;

[0062] Step S22: If the judgment result in the above step S21 is yes, the initial abscissa of the current preview tracking point B is equal to the abscissa Ax of the current vehicle position A plus the current preview distance L, and the horizontal and vertical coordinates (Bx, By) of the position of the current preview tracking point B are determined according to the positional relationship between the initial abscissa and the parking trajectory planning segment;

[0063] Among them, if the initial abscissa is greater than the abscissa of the end point Z of the parking trajectory planning segment, that is, the initial abscissa exceeds the abscissa of the end point Z of the parking trajectory planning segment, the horizontal and vertical coordinates (Bx, By) of the position of the current preview tracking point B are determined as the horizontal and vertical coordinates of the end point Z of the parking trajectory planning segment;

[0064] Among them, if the initial abscissa is less than the abscissa of the starting point Q of the parking trajectory planning segment, that is, the initial abscissa does not reach the abscissa of the starting point Q of the parking trajectory planning segment, the horizontal and vertical coordinates (Bx, By) of the position of the current preview tracking point B are determined as the horizontal and vertical coordinates of the starting point Q of the parking trajectory planning segment;

[0065] Step S23: If the judgment result in the above step S21 is no, the initial ordinate of the current preview tracking point B is equal to the ordinate Ay of the current vehicle position A plus the current preview distance L, and the horizontal and vertical coordinates (Bx, By) of the position of the current preview tracking point B are determined according to the positional relationship between the initial ordinate and the parking trajectory planning segment;

[0066] Among them, if the initial ordinate is greater than the ordinate of the end point Z of the parking trajectory planning segment, that is, the initial ordinate exceeds the ordinate of the end point Z of the parking trajectory planning segment, the horizontal and vertical coordinates (Bx, By) of the position of the current preview tracking point B are determined as the horizontal and vertical coordinates of the end point Z of the parking trajectory planning segment;

[0067] Among them, if the initial ordinate is less than the ordinate of the starting point Q of the parking trajectory planning segment, that is, the initial ordinate does not reach the ordinate of the starting point Q of the parking trajectory planning segment, the horizontal and vertical coordinates (Bx, By) of the position of the current preview tracking point B are determined as the horizontal and vertical coordinates of the starting point Q of the parking trajectory planning segment.

[0068] More specifically, the parking trajectory planning segment is an arc or a straight line;

[0069] Among them, if the parking trajectory planning segment is an arc, then determining the horizontal and vertical coordinates (Bx, By) of the position of the current preview tracking point B according to the positional relationship between the initial abscissa and the parking trajectory planning segment specifically further includes:

[0070] If the initial abscissa is greater than or equal to the abscissa of the starting point Q of the arc and less than or equal to the abscissa of the ending point Z of the arc, then determine the initial abscissa as the abscissa Bx of the position of the current preview tracking point B, and determine the ordinate By of the position of the current preview tracking point B according to the center coordinates and radius of the arc;

[0071] Specifically, the formula equation corresponding to the arc can be determined according to the center coordinates and radius of the arc. Further, substitute the abscissa Bx of the position of the current preview tracking point B obtained into this formula equation, and then the ordinate By of the position of the current preview tracking point B can be calculated and determined;

[0072] Moreover, the determination of the abscissa and ordinate of the position of the current preview tracking point B according to the positional relationship between the initial ordinate and the parking trajectory planning segment specifically further includes:

[0073] If the initial ordinate is greater than or equal to the ordinate of the starting point Q of the arc and less than or equal to the ordinate of the ending point Z of the arc, then determine the initial ordinate as the ordinate By of the position of the current preview tracking point B, and determine the abscissa Bx of the position of the current preview tracking point B according to the center coordinates and radius of the arc;

[0074] Specifically, the formula equation corresponding to the arc can be determined according to the center coordinates and radius of the arc. Further, substitute the ordinate By of the position of the current preview tracking point B obtained into this formula equation, and then the abscissa Bx of the position of the current preview tracking point B can be calculated and determined.

[0075] Among them, if the parking trajectory planning segment is a straight line, then the determination of the abscissa and ordinate (Bx, By) of the position of the current preview tracking point B according to the positional relationship between the initial abscissa and the parking trajectory planning segment specifically further includes:

[0076] If the initial abscissa is greater than or equal to the abscissa of the starting point Q of the straight line and less than or equal to the abscissa of the ending point Z of the straight line, that is, the abscissa Bx is on the arc QZ of the parking trajectory planning segment, then determine the initial abscissa as the abscissa Bx of the position of the current preview tracking point B, and determine the ordinate of the position of the current preview tracking point B according to the straight line equation corresponding to the straight line and the initial abscissa;

[0077] Specifically, substitute the abscissa Bx of the position of the current preview tracking point B into the straight line formula equation corresponding to the straight line, and then the ordinate By of the position of the current preview tracking point B can be calculated;

[0078] Moreover, the determination of the abscissa and ordinate (Bx, By) of the position of the current preview tracking point B according to the positional relationship between the initial ordinate and the parking trajectory planning segment specifically includes:

[0079] If the initial ordinate is greater than or equal to the ordinate of the starting point Q of the straight line and less than or equal to the ordinate of the ending point Z of the straight line, that is, the abscissa Bx is on the straight line QZ of the parking trajectory planning segment, then determine the initial ordinate as the ordinate By of the position of the current preview tracking point B, and determine the abscissa Bx of the position of the current preview tracking point B according to the straight line equation corresponding to the straight line and the initial ordinate;

[0080] Specifically, substituting the abscissa Bx of the position of the current preview tracking point B into the straight line formula equation corresponding to the straight line, the ordinate Bx of the position of the current preview tracking point B can be calculated;

[0081] Step S3, obtain the current vehicle heading angle, and determine the current front wheel steering angle according to the current vehicle position, the current vehicle heading angle, the current preview distance, and the position of the current preview tracking point;

[0082] Exemplarily, the determining the current front wheel steering angle according to the current vehicle position, the current vehicle heading angle, the current preview distance, and the position of the current preview tracking point includes:

[0083] Specifically, calculate and determine the current front wheel steering angle according to the following formula;

[0084]

[0085]

[0086] Wherein, δ is the current front wheel steering angle, l is the given vehicle wheelbase, L is the current preview distance, Ax is the abscissa of the current vehicle position, Ay is the ordinate of the current vehicle position, Bx is the abscissa of the position of the current preview tracking point, By is the ordinate of the position of the current preview tracking point, and yaw is the current vehicle heading angle;

[0087] Step S4, determine the current steering wheel steering angle according to the current front wheel steering angle.

[0088] Exemplarily, the determining the current steering wheel steering angle according to the current front wheel steering angle includes:

[0089] Specifically, calculate and determine the current steering wheel steering angle according to the following formula;

[0090] θ = kδ + b

[0091] Wherein, θ is the current steering wheel steering angle, k is the preset linear fitting coefficient, δ is the current front wheel steering angle, and b is the preset linear fitting offset constant;

[0092] Specifically, the formula θ = kδ + b is a linear fitting of the relationship between the front wheel angle and the steering wheel angle of the vehicle, and quadratic linear or non-linear fitting can also be used; the finally calculated current steering wheel angle θ can be subjected to limit filtering to obtain the final control amount.

[0093] When applying the method of the embodiment of the present invention for automatic parking trajectory tracking, its preview tracking point is dynamically calculated according to the real-time position of the vehicle, and there is no need for a preview sequence of points. Instead, the planned path and the real-time position information of the vehicle in the earth coordinate system are directly used. Compared with the traditional method of converting the discrete point sequence of the desired path in the earth coordinate system into discrete points in the vehicle coordinate system and then determining the trajectory tracking point according to the difference between the preview distance and the target distance, the cumbersome operation of coordinate conversion is cancelled, there is no need for a preview sequence of points, the calculation amount of the tracking control algorithm can be reduced, the CPU memory space can be saved, and the performance requirements of the algorithm for the hardware can be reduced.

[0094] Refer to Figure 2 , another embodiment of the present invention proposes an automatic parking trajectory tracking system for implementing the automatic parking trajectory tracking method described in the above embodiment. The system includes:

[0095] A preview distance determination unit 1, configured to obtain the current vehicle speed and the current vehicle gear, and determine the current preview distance according to the current vehicle speed and the current vehicle gear;

[0096] A preview tracking point determination unit 2, configured to obtain the parking trajectory planning segment and the current vehicle position, and determine the current preview tracking point position according to the parking trajectory planning segment, the current preview distance, and the current vehicle position;

[0097] A front wheel angle determination unit 3, configured to determine the current front wheel angle according to the current vehicle position, the current vehicle heading angle, the current preview distance, and the current preview tracking point position; and

[0098] A steering wheel angle determination unit 4, configured to determine the current steering wheel angle according to the current front wheel angle.

[0099] The system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0100] It should be noted that the system described in the above embodiment corresponds to the method described in the above embodiment. Therefore, the parts not detailed in the system described in the above embodiment can be obtained by referring to the content of the method described in the above embodiment, and will not be elaborated here.

[0101] Moreover, when the automatic parking trajectory tracking system described in the above embodiments is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium.

[0102] Another embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the automatic parking trajectory tracking method described in the above embodiments is implemented.

[0103] Specifically, the computer-readable storage medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal, and software distribution medium, etc.

[0104] The embodiments of the present invention have been described above. The above description is exemplary and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments. The selection of the terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other ordinary skill in the art in the technical field to understand the disclosed embodiments.

Claims

1. An automatic parking trajectory tracking method, characterized in that, Including: Obtain the current vehicle speed and the current vehicle gear position, and determine the current preview distance according to the current vehicle speed and the current vehicle gear position; Obtain the parking trajectory planning section and the current vehicle position, and determine the current preview tracking point position according to the parking trajectory planning section, the current preview distance and the current vehicle position; Obtain the current vehicle heading angle, and determine the current front wheel steering angle according to the current vehicle position, the current vehicle heading angle, the current preview distance and the current preview tracking point position; Determine the current steering wheel steering angle according to the current front wheel steering angle; Wherein, determining the current preview tracking point position according to the parking trajectory planning section, the current preview distance and the current vehicle position includes: Judge whether the change in the abscissa between the starting point and the ending point of the parking trajectory planning section is greater than the change in the ordinate; if so, the initial abscissa of the current preview tracking point is equal to the abscissa of the current vehicle position plus the current preview distance, and determine the horizontal and vertical coordinates of the current preview tracking point position according to the positional relationship between the initial abscissa and the parking trajectory planning section; if not, the initial ordinate of the current preview tracking point is equal to the ordinate of the current vehicle position plus the current preview distance, and determine the horizontal and vertical coordinates of the current preview tracking point position according to the positional relationship between the initial ordinate and the parking trajectory planning section.

2. The automatic parking trajectory tracking method according to claim 1, wherein The determining the current preview distance according to the current vehicle speed and the current vehicle gear position includes: If the current vehicle gear position is the forward gear position, the current preview distance L is: L = K × V + L min ; If the current vehicle gear position is the reverse gear position, the current preview distance L is: L = -K × V – L min ; Moreover, |L| is less than or equal to a preset L max ; Where K is a preset coefficient, V is the current vehicle speed, and L min is the preset minimum sight distance, and L max is the preset maximum sight distance.

3. The automatic parking trajectory tracking method according to claim 1, wherein Wherein, The determining the horizontal and vertical coordinates of the current preview tracking point position according to the positional relationship between the initial abscissa and the parking trajectory planning section specifically includes: if the initial abscissa is greater than the abscissa of the ending point of the parking trajectory planning section, the horizontal and vertical coordinates of the current preview tracking point position are determined as the horizontal and vertical coordinates of the ending point of the parking trajectory planning section; if the initial abscissa is less than the abscissa of the starting point of the parking trajectory planning section, the horizontal and vertical coordinates of the current preview tracking point position are determined as the horizontal and vertical coordinates of the starting point of the parking trajectory planning section. Wherein, the determining the horizontal and vertical coordinates of the current preview tracking point position according to the positional relationship between the initial ordinate and the parking trajectory planning section specifically includes: if the initial ordinate is greater than the ordinate of the ending point of the parking trajectory planning section, the horizontal and vertical coordinates of the current preview tracking point position are determined as the horizontal and vertical coordinates of the ending point of the parking trajectory planning section; if the initial ordinate is less than the ordinate of the starting point of the parking trajectory planning section, the horizontal and vertical coordinates of the current preview tracking point position are determined as the horizontal and vertical coordinates of the starting point of the parking trajectory planning section.

4. The automatic parking trajectory tracking method according to claim 1, wherein, If the parking trajectory planning section is an arc, the determining the horizontal and vertical coordinates of the current preview tracking point position according to the positional relationship between the initial abscissa and the parking trajectory planning section specifically includes: if the initial abscissa is greater than or equal to the abscissa of the starting point of the arc and less than or equal to the abscissa of the ending point of the arc, determine the initial abscissa as the abscissa of the current preview tracking point position, and determine the ordinate of the current preview tracking point position according to the center coordinates and radius of the arc; Moreover, determining the horizontal and vertical coordinates of the current preview tracking point according to the positional relationship between the initial vertical coordinate and the parking trajectory planning segment specifically includes: If the initial vertical coordinate is greater than or equal to the vertical coordinate of the starting point of the arc and less than or equal to the vertical coordinate of the ending point of the arc, then determine the initial vertical coordinate as the vertical coordinate of the current preview tracking point, and determine the horizontal coordinate of the current preview tracking point according to the center coordinates and radius of the arc.

5. The automatic parking trajectory tracking method according to claim 1, wherein If the parking trajectory planning segment is a straight line, then determining the horizontal and vertical coordinates of the current preview tracking point according to the positional relationship between the initial horizontal coordinate and the parking trajectory planning segment specifically includes: If the initial horizontal coordinate is greater than or equal to the horizontal coordinate of the starting point of the straight line and less than or equal to the horizontal coordinate of the ending point of the straight line, then determine the initial horizontal coordinate as the horizontal coordinate of the current preview tracking point, and determine the vertical coordinate of the current preview tracking point according to the straight-line equation corresponding to the straight line and the initial horizontal coordinate; Moreover, determining the horizontal and vertical coordinates of the current preview tracking point according to the positional relationship between the initial vertical coordinate and the parking trajectory planning segment specifically includes: If the initial vertical coordinate is greater than or equal to the vertical coordinate of the starting point of the straight line and less than or equal to the vertical coordinate of the ending point of the straight line, then determine the initial vertical coordinate as the vertical coordinate of the current preview tracking point, and determine the horizontal coordinate of the current preview tracking point according to the straight-line equation corresponding to the straight line and the initial vertical coordinate.

6. The automatic parking trajectory tracking method according to claim 1, characterized in that Determining the current front-wheel steering angle according to the current vehicle position, the current vehicle heading angle, the current preview distance, and the current preview tracking point position includes: Specifically calculating and determining the current front-wheel steering angle according to the following formula; where δ is the current front-wheel steering angle, l is the given wheelbase of the vehicle, L is the current preview distance, Ax is the horizontal coordinate of the current vehicle position, Ay is the vertical coordinate of the current vehicle position, Bx is the horizontal coordinate of the current preview tracking point position, By is the vertical coordinate of the current preview tracking point position, and yaw is the current vehicle heading angle.

7. The automatic parking trajectory tracking method according to any one of claims 1 to 6, characterized in that, Determining the current steering wheel angle according to the current front-wheel steering angle includes: Specifically calculating and determining the current steering wheel angle according to the following formula; θ = kδ + b where θ is the current steering wheel angle, k is the preset linear fitting coefficient, δ is the current front-wheel steering angle, and b is the preset linear fitting offset constant.

8. An automatic parking trajectory tracking system, characterized in that, A system for implementing the automatic parking trajectory tracking method according to any one of claims 1-7, the system includes: A preview distance determination unit, configured to obtain the current vehicle speed and the current vehicle gear, and determine the current preview distance according to the current vehicle speed and the current vehicle gear; A preview tracking point determination unit, configured to obtain the parking trajectory planning segment and the current vehicle position, and determine the current preview tracking point position according to the parking trajectory planning segment, the current preview distance, and the current vehicle position; A front-wheel steering angle determination unit, configured to determine the current front-wheel steering angle according to the current vehicle position, the current vehicle heading angle, the current preview distance, and the current preview tracking point position; and A steering wheel angle determination unit, configured to determine the current steering wheel angle according to the current front-wheel steering angle.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the automatic parking trajectory tracking method described in any one of claims 1-7.

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