A reversing control method and system with automatic tracking

Abstract

This invention provides an automatic reversing control method and system for controlling a vehicle to reverse after receiving a reversing trajectory command. The reversing control method includes the following steps: acquiring the vehicle's driving trajectory; selecting multiple trajectory points from the driving trajectory and storing the multiple trajectory points; generating reversing path planning data based on the stored multiple trajectory points; and generating reversing control data based on the reversing path trajectory data; and controlling the vehicle to reverse according to the reversing control data. This invention reduces the amount of driving trajectory storage by classifying and filtering cached data. It eliminates the need to store the entire driving trajectory, requiring only partial storage. The historical trajectory of the vehicle is saved in memory with minimal information, and the reversing function can be achieved solely based on GPS information.

Description

Technical Field

[0001] This invention relates to the field of vehicle automatic control, and in particular to a reversing control method and system with automatic tracking. Background Technology

[0002] "Trajectory-following reversing" refers to the reversing function. The reversing assist function in a driver assistance system records the driving route before reversing and can automatically reverse a corresponding distance, without the driver needing to control the steering wheel. It features automatic trajectory-following reversing, especially useful in narrow alleys and other confined spaces, supporting automatic reversing back along the original path without manual operation.

[0003] However, existing reversing control systems require recording the entire driving trajectory and saving GPS (Global Positioning System) data, such as steering wheel angle and throttle opening, which leads to insufficient memory and excessively large cached data; consequently, direct path planning based on the saved trajectory is not possible.

[0004] Furthermore, for route planning at a designated location, vehicles with long distances (greater than 20 meters) as the destination cannot be automatically obtained and need to be specified by the user on the map. At the same time, vehicles that support this function have a higher level of autonomous driving (L3+) and rely on high-precision maps. On the other hand, there are currently few vehicles that rely on radar cameras to activate the automatic cruise and reversing function, and they also have high requirements for the computing power of autonomous driving chips. Summary of the Invention

[0005] One objective of this invention is to provide an automatic reversing control method that reduces the amount of driving trajectory storage required, saves the vehicle's historical trajectory with minimal memory information, and enables the reversing function based solely on GPS information.

[0006] A further objective of this invention is to expand the applicability of automatic tracking, enabling L2+ level vehicles to automatically reverse to a designated destination without the need for high-precision maps, and eliminating the need for L3+ level autonomous driving vehicles.

[0007] Specifically, the present invention provides an automatic reversing control method for controlling a vehicle to reverse after receiving a reversing tracking command. The reversing control method includes the following steps:

[0008] Obtain the vehicle's driving trajectory, filter out multiple trajectory points from the driving trajectory, and store the multiple trajectory points;

[0009] Reversing path planning data is generated based on the stored multiple trajectory points, and reversing control data is generated based on the reversing path trajectory data;

[0010] The vehicle is reversed according to the reversing control data.

[0011] Furthermore, the process of selecting multiple trajectory points from the driving trajectory includes the following steps:

[0012] Obtain the trajectory points to be recorded from the driving trajectory;

[0013] When the trajectory point to be recorded does not belong to the first X trajectory points in the entire driving trajectory points, determine whether to record the trajectory point to be recorded based on the first N trajectory points of the trajectory point to be recorded.

[0014] When determining the trajectory point to be recorded, the trajectory point to be recorded is added to the cached data.

[0015] Furthermore, the process of selecting multiple trajectory points from the driving trajectory includes the following steps:

[0016] If the trajectory point to be recorded belongs to the first X trajectory points in the entire driving trajectory, the first X trajectory points are added to the cached data.

[0017] Furthermore, the step of determining whether to record the trajectory point based on the first N trajectory points of the trajectory point to be recorded includes the following steps:

[0018] Obtain the positions of the trajectory point B to be recorded and the trajectory point A preceding the trajectory point A to be recorded, and calculate the center position O of the circle where the trajectory point B to be recorded and the trajectory point A preceding the trajectory point A is located, and the straight-line distance d between the trajectory point B to be recorded and the trajectory point A preceding the trajectory point A to be recorded.

[0019] The radius r is calculated based on the straight-line distance d and the angle between the trajectory point B to be recorded and the trajectory point A preceding the trajectory point to be recorded.

[0020] The error of the actual path between the previous trajectory point A and the trajectory point B to be recorded is calculated based on the radius r and the straight-line distance d.

[0021] Furthermore, in the step of calculating the radius r based on the straight-line distance d and the angle between the trajectory point B to be recorded and the trajectory point A preceding the trajectory point to be recorded, the radius r is calculated according to the following formula:

[0022] r = d / (2*sin(∠AOB / 2))

[0023] Furthermore, in the step of calculating the error of the actual path between the previous trajectory point A and the trajectory point B to be recorded based on the radius r and the straight-line distance d, the error is calculated using the following formula:

[0024]

[0025] Furthermore, the error is the maximum value of the distance d perpendicular to the straight line.

[0026] Furthermore, after calculating the error of the actual path between the previous trajectory point A and the trajectory point B to be recorded based on the radius r and the straight-line distance d, the method further includes the following steps:

[0027] If the error is greater than the preset error value, then the trajectory point to be recorded is retained;

[0028] If the error is less than or equal to the preset error value, the trajectory point to be recorded will not be retained.

[0029] Furthermore, when the number of the retained trajectory points to be recorded exceeds the preset capacity, the first retained trajectory point to be recorded will be updated by the next adjacent trajectory point to be recorded.

[0030] The present invention also discloses an automatic tracking reversing control system, including a control device, the control device including a memory and a processor, the memory storing a control program, the control program being executed by the processor to implement the automatic tracking reversing control method as described above.

[0031] This invention acquires the vehicle's driving trajectory, filters trajectory points within that trajectory, selectively selects and stores these points, generates reversing path planning data based on the stored trajectory points, generates reversing control data based on the reversing path data, and finally controls the vehicle to reverse according to the reversing control data. This reduces the amount of driving trajectory storage required, saving the vehicle's historical trajectory in minimal memory, and enabling line-following reversing functionality solely based on GPS information.

[0032] Furthermore, the present invention determines whether to record the trajectory point to be recorded based on the first N trajectory points of the target trajectory point, thereby further filtering and retaining the recorded data, reducing the storage amount of driving trajectory, saving the vehicle's historical trajectory with minimal memory information, and realizing the function of reversing by relying solely on GPS information.

[0033] The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0034] The following sections will describe some specific embodiments of the invention in detail by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0035] Figure 1 This is a first control flowchart according to an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of a trajectory filtering method according to an embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram of error calculation according to an embodiment of the present invention;

[0038] Figure 4 This is a schematic diagram of the historical trajectory of an actual road curve according to an embodiment of the present invention;

[0039] Figure 5 This is a schematic diagram of the historical trajectory of a straight section of a road according to an embodiment of the present invention;

[0040] Figure 6 This is a system flowchart according to an embodiment of the present invention;

[0041] Figure 7 This is a schematic diagram of an electronic architecture according to an embodiment of the present invention. Detailed Implementation

[0042] Figure 1 This is a flowchart of a reversing control system with automatic tracking according to an embodiment of the present invention. Figure 2 This is a schematic diagram of a trajectory filtering method according to an embodiment of the present invention. In one embodiment, such as... Figure 1 and Figure 2 As shown, this reversing control method for automatic vehicle tracking performs reversing control on the vehicle after receiving an automatic reversing command. The reversing control method mainly includes the following steps:

[0043] S1. Obtain the vehicle's driving trajectory, filter out multiple trajectory points from the driving trajectory, and store multiple trajectory points;

[0044] S2. Generate reversing path planning data based on multiple stored trajectory points, and generate reversing control data based on the reversing path trajectory data;

[0045] S3. Control the vehicle to reverse according to the reversing control data.

[0046] In this embodiment, the vehicle's driving trajectory is acquired, and trajectory points within the trajectory are selectively filtered and stored. Reversing path planning data is generated based on the stored trajectory points, and reversing control data is generated based on the reversing path data. Finally, the vehicle is controlled to reverse according to the reversing control data. This reduces the amount of driving trajectory storage, saving the vehicle's historical trajectory in memory with minimal information, and enabling the reversing function based solely on GPS information.

[0047] In a further embodiment, such as Figure 2 As shown, when filtering trajectory points from the driving trajectory, the process first obtains the trajectory points to be recorded from the driving trajectory points and determines whether the trajectory point to be recorded belongs to the first X trajectory points in the entire driving trajectory. If the trajectory point to be recorded belongs to the first X trajectory points in the entire driving trajectory, it is directly retained and added to the cache data. If the trajectory point to be recorded does not belong to the first X trajectory points in the entire driving trajectory, it is necessary to determine whether the trajectory point to be recorded needs to be recorded based on the first N trajectory points of the trajectory point to be recorded.

[0048] In this context, X can be any non-zero natural number among the first X trajectory points. Similarly, the N of the first N trajectory points of the trajectory point to be recorded is used to determine whether the trajectory point to be recorded needs to be recorded. N is also any non-zero natural number. In this embodiment, X is preferably 3 and N is preferably 1. Specifically, it is first necessary to determine whether the trajectory point to be recorded is among the first 3 trajectory points of the entire driving trajectory. If it is among the first 3 trajectory points, it is directly retained. If it is not among the first 3 trajectory points, the previous point of the trajectory point and the trajectory point are used to jointly determine whether the trajectory point meets the condition for being retained. If it meets the condition, the trajectory point to be recorded is retained. If it does not meet the condition, the trajectory point is not recorded.

[0049] In this embodiment, the system determines whether to record the trajectory point based on the first N trajectory points of the target trajectory point, thereby further filtering and retaining the recorded data, reducing the storage amount of driving trajectory, saving the vehicle's historical trajectory with minimal memory information, and enabling the function of reversing by relying solely on GPS information.

[0050] Furthermore, by filtering the data on the driving trajectory, there is no need to record information such as steering wheel angle and throttle opening in real time, thus reducing the reliance on autonomous driving.

[0051] Figure 3 This is a schematic diagram of error calculation according to an embodiment of the present invention. Figure 2 and Figure 3As shown, in a specific embodiment, after determining that the trajectory point to be recorded does not belong to the first 3 trajectory points, it is necessary to determine whether to retain the trajectory point to be recorded based on the trajectory point and the trajectory point preceding it. First, the positions of the trajectory point to be recorded B and the trajectory point preceding it A are obtained, thereby calculating the center position O of the trajectory point to be recorded B and the straight-line distance d between the trajectory point to be recorded B and the trajectory point preceding it A, and thus calculating the radius r. After calculating the radius r, the error between the trajectory point to be recorded B and the trajectory point preceding it A is calculated according to the formula, and the error value is used to determine whether to retain the trajectory point to be recorded.

[0052] Specifically, the position information of the trajectory point B to be recorded and the trajectory point A before the trajectory point to be recorded must first be obtained. The straight-line distance d and the center position O of the circle are calculated, and then ∠AOB is obtained. If ∠AOB > 180°, then ∠AOB = 360° - ∠AOB; if ∠AOB < 180°, then the value of ∠AOB remains unchanged, where ∠AOB must be taken as the absolute value.

[0053] Then, the radius r is calculated using the following formula:

[0054] r = d / (2*sin(∠AOB / 2))

[0055] After calculating the radius r, the error value is calculated based on the radius r and the straight-line distance d. The error is the maximum value of the perpendicular straight-line distance d, and the formula for calculating the error is as follows.

[0056]

[0057] Finally, after calculating and obtaining the error, the error value is judged. If the error is greater than the preset error value, the trajectory point to be recorded is retained; if the error is less than or equal to the preset error value, the trajectory point to be recorded is not retained.

[0058] like Figure 4 and Figure 5 As shown, Figure 4 and Figure 5The circles in the diagram represent the track points to be retained. The density of these track points varies depending on the vehicle's trajectory. When the vehicle is on a straight section, the error value will consistently be less than the preset result. In this case, the distance between the current track point and the previous track point is used to determine whether the current track point should be retained. If the distance exceeds the preset distance, the track point is retained; otherwise, it is not. When the vehicle is on a curve, the error value can vary. If the error value of the track point is greater than the preset error, the track point should be retained. Similarly, if the error of the track point is less than the preset error, but the distance between it and the previous retained track point is greater than the preset distance, the track point should also be retained to ensure greater continuity among the retained track points.

[0059] Specifically, firstly, the error value of the trajectory point to be recorded is calculated by comparing it with the previous trajectory point. If the error value is greater than a preset error, the trajectory point to be recorded is retained. If the error value is less than the preset error, it is further determined whether the distance between the trajectory point to be recorded and the previously retained trajectory point is greater than a preset distance. If it is greater, the trajectory point to be recorded is retained; if it is less, the trajectory point to be recorded is not retained.

[0060] In this embodiment, by judging the error of the driving trajectory, it is determined whether the trajectory point to be recorded needs to be determined, making the data filtering more targeted and thus making the retained data more accurate.

[0061] Furthermore, by filtering the data on the driving trajectory, there is no need to record information such as steering wheel angle and throttle opening in real time, thus reducing the reliance on autonomous driving.

[0062] In one embodiment, such as Figure 2 As shown, when the number of track points to be recorded stored in the memory exceeds the preset data storage capacity, the first track point to be recorded will be updated by the next adjacent track point to be recorded, thereby achieving data replacement and ensuring that the latest track point data is always retained within the preset data capacity, so that the user can perform the automatic reversing function at any time.

[0063] In this embodiment, by updating the data, the latest trajectory points are always retained in the memory, thereby ensuring that the latest trajectory point data is always retained within the preset data capacity, so that the user can perform the automatic reversing function at any time.

[0064] This invention also discloses an automatic tracking reversing control system, such as... Figure 6 and Figure 7As shown, the control system includes a control device, which includes a memory and a processor. The memory stores a control program, which, when executed by the processor, is used to implement the automatic tracking reversing control method described above.

[0065] In one specific embodiment, such as Figure 6 and Figure 7 As shown, the electronic architecture of this automatic reversing system mainly includes a central control screen, a vehicle gateway, a GPS module, and an ADCU (Autonomous Driving Control Unit). Specifically, after the vehicle starts moving, the ADCU begins recording the filtered trajectory points according to the aforementioned trajectory point filtering method and writes them to the storage area. It continuously saves data points within 100 meters of the vehicle, using a cyclical storage method. Users can activate or deactivate the automatic reversing function via the central control screen. When the user activates the function on the central control screen, the function command is sent to the ADCU through the vehicle gateway. The ADCU then reads all data from the buffer, parses the data, and progressively converts it from the current point and the last point in the data into a path planning data format (as shown in the historical trajectory point filtering method diagram, from point 4 to point 3, point 3 to point 2, point 2 to point 1, thus segmenting and calculating vehicle control information). No further path planning is required. Then, a vehicle control command is generated and sent to the vehicle control module, which then controls the vehicle's movement. Meanwhile, each time a vehicle control command is issued, the ADCU will report the current progress to the central screen and display it to the user in real time; when the user clicks the pause or stop function button on the central screen, the central screen sends the corresponding command to the ADCU, and the ADCU then determines whether to disengage or pause the vehicle.

[0066] In this embodiment, the user can control the reversing tracking function in real time through the central control screen, and monitor the reversing process in real time through the central control screen, thereby ensuring control of the vehicle's automatic reversing.

[0067] Therefore, those skilled in the art should recognize that although numerous exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Thus, the scope of the present invention should be understood and construed as covering all such other variations or modifications.

Claims

1. A reversing control method with automatic tracking, characterized in that, The method is used to control the vehicle in reverse after receiving a reversing tracking command. The reversing control method includes the following steps: Obtain the vehicle's driving trajectory, filter out multiple trajectory points from the driving trajectory, and store the multiple trajectory points; Reversing path planning data is generated based on the stored multiple trajectory points, and reversing control data is generated based on the reversing path planning data; Control the vehicle to reverse according to the reversing control data; The process of selecting multiple trajectory points from the driving trajectory includes the following steps: Obtain the trajectory points to be recorded from the driving trajectory; When the trajectory point to be recorded does not belong to the first X trajectory points in the entire driving trajectory points, determine whether to record the trajectory point to be recorded based on the first N trajectory points of the trajectory point to be recorded. When determining the trajectory point to be recorded, the trajectory point to be recorded is added to the cache data; The step of determining whether to record the trajectory point based on the first N trajectory points of the trajectory point to be recorded includes the following steps: Obtain the positions of the trajectory point B to be recorded and the trajectory point A preceding the trajectory point A to be recorded, and calculate the center position O of the circle where the trajectory point B to be recorded and the trajectory point A preceding the trajectory point A is located, and the straight-line distance d between the trajectory point B to be recorded and the trajectory point A preceding the trajectory point A to be recorded. The radius r is calculated based on the straight-line distance d and the angle between the trajectory point B to be recorded and the trajectory point A preceding the trajectory point to be recorded. The error of the actual path between the previous trajectory point A and the trajectory point B to be recorded is calculated based on the radius r and the straight-line distance d.

2. The reversing control method according to claim 1, characterized in that, The process of selecting multiple trajectory points from the driving trajectory includes the following steps: If the trajectory point to be recorded belongs to the first X trajectory points in the entire driving trajectory, the first X trajectory points are added to the cached data.

3. The reversing control method according to claim 1, characterized in that, In the step of calculating the radius r based on the straight-line distance d and the angle between the trajectory point B to be recorded and the trajectory point A preceding the trajectory point to be recorded, the radius r is calculated according to the following formula: r = d / (2*sin(∠AOB / 2)).

4. The reversing control method according to claim 3, characterized in that, The step of calculating the error of the actual path between the previous trajectory point A and the trajectory point B to be recorded based on the radius r and the straight-line distance d is obtained by the following formula:

5. The reversing control method according to claim 4, characterized in that, The error is the maximum value of the perpendicular distance d of the line.

6. The reversing control method according to claim 5, characterized in that, After calculating the error of the actual path between the previous trajectory point A and the trajectory point B to be recorded based on the radius r and the straight-line distance d, the method further includes the following steps: If the error is greater than the preset error value, then the trajectory point to be recorded is retained; If the error is less than or equal to the preset error value, the trajectory point to be recorded will not be retained.

7. The reversing control method according to claim 6, characterized in that, When the number of the reserved trajectory points to be recorded exceeds the preset capacity, the first reserved trajectory point to be recorded will be updated by the next adjacent trajectory point to be recorded.

8. A reversing control system with automatic tracking, characterized in that, The system includes a control device, which comprises a memory and a processor. The memory stores a control program, which, when executed by the processor, is used to implement the automatic tracking reversing control method according to any one of claims 1-7.

Images