Parking space angular point correction method based on ultrasonic sensor

Abstract

The invention discloses a parking space angular point correction method based on an ultrasonic sensor, and the method comprises the steps: obtaining the horizontal sections and angular points of left and right obstacles of a space parking space according to the jump state of ultrasonic radar detection data; obstacle coordinates are calculated according to data of two ultrasonic radars on the sides of the vehicle; kalman filtering is carried out on the ultrasonic obstacle coordinate data, and noise points in a horizontal section of an obstacle are removed; the nearest point ID of the horizontal section of the obstacle near the corrected angular point to the vehicle and corresponding ultrasonic data are searched; according to coordinates of a nearest point in a certain range near an angular point and ultrasonic data, the influence of a beam angle on the ultrasonic data is corrected, and x and y coordinates corresponding to the angular point are predicted; the invention aims to provide a parking space angular point correction scheme based on an ultrasonic sensor, and aims to realize high-precision detection and correction of parking space angular points through algorithm optimization, so that the accuracy and reliability of automatic parking are improved.

Description

Technical Field

[0001] The invention relates to the technical field of parking space corner point correction, and in particular to a parking space corner point correction method based on an ultrasonic sensor. Background Art

[0002] With the continuous development of intelligent transportation systems, automated parking technology has received more and more attention. In the process of assisted parking, accurate detection of parking corners is crucial for the correct parking of the vehicle. Traditional ultrasonic sensors may lead to inaccurate positioning of parking corners due to the limitation of beam angle in parking detection, affecting parking efficiency and safety. Therefore, it is particularly important to develop a solution that can accurately identify and correct parking corners. Summary of the invention

[0003] In view of the above existing problems, the present invention is proposed.

[0004] Therefore, the present invention provides a parking space corner point correction method based on ultrasonic sensors, aiming to achieve high-precision detection and correction of parking space corner points through algorithm optimization, thereby improving the accuracy and reliability of automated parking.

[0005] In order to solve the above technical problems, the present invention provides the following technical solution, a parking space corner correction method based on ultrasonic sensor, comprising:

[0006] According to the jump state of ultrasonic radar detection data, the horizontal segments and corner points of the obstacles on the left and right sides of the parking space are obtained;

[0007] Calculate the coordinates of the obstacle based on the data from the two ultrasonic radars on the side of the vehicle;

[0008] Perform Kalman filtering on the ultrasonic obstacle coordinate data to remove noise points in the horizontal section of the obstacle;

[0009] Find the ID of the closest point of the horizontal section of the obstacle near the corrected corner point to the vehicle, and the corresponding ultrasonic data;

[0010] According to the coordinates of the nearest point within a certain range near the corner point and the ultrasonic data, the influence of the beam angle on the ultrasonic data is corrected, and the x, y coordinates corresponding to the corner point are predicted.

[0011] As a preferred solution of the parking space corner point correction method based on ultrasonic sensor described in the present invention, wherein: the calculation of obstacle coordinates includes using the parking space corner point coordinates of the previous frame calculated and corrected by the calculation method of this process as the obstacle coordinates of this frame.

[0012] As a preferred solution of the parking space corner correction method based on ultrasonic sensor of the present invention, wherein: the Kalman filtering of ultrasonic obstacle coordinate data includes, according to the vehicle running state, including speed, acceleration, heading angle, according to the probabilistic robot kinematic model, deriving the vehicle position at the next moment, that is, the state equation:

[0013]

[0014] Add noise as Gaussian white noise back:

[0015]

[0016] Perform coordinate conversion based on the obstacle position in the previous frame and the predicted vehicle position in this frame:

[0017]

[0018] Among them, X', Y', θ' predict the vehicle position and azimuth of the next frame, x, y, θ are the current vehicle position and azimuth, v is the current translation speed, ω is the current rotation speed, and Δt is the time interval;

[0019] After calculating the predicted obstacle position, the difference between the predicted value and the measured value is calculated, and points exceeding 30 cm are filtered out.

[0020] As a preferred solution of the parking space corner point correction method based on ultrasonic sensor described in the present invention, wherein: the certain range near the corner point includes the range of 10 points after the nearest point ID.

[0021] As a preferred solution of the parking space corner correction method based on ultrasonic sensor described in the present invention, the influence of the correction beam angle on the ultrasonic data includes performing least square fitting on the horizontal segment coordinates of the first and second obstacles after filtering, and calculating the spatial parking space corner coordinates (x1, y1), (x2, y2) formed by the combination of the closest point obstacle 1 and obstacle 2 according to the fitting straight lines k and b;

[0022] For the (x, y) coordinates of the 40 points after the nearest point (a, b), calculate the x jump situation of each point before and after, remove the points with a jump of more than 10 cm, and then calculate the xy jump situation every 8 points. If it exceeds 30 cm, update the nearest point to the previous non-jump point before the jump interval, and perform the least squares fitting from the nearest point to the remaining points:

[0023]

[0024] By calculating the coordinates of the nearest point b corresponding to a as the least squares fitting corner coordinates, and calculating the distance from the remaining points to the fitting straight line, according to the distance Filter out points exceeding 30cm;

[0025] Among them, x i ,y i The coordinates of all points from the nearest point to the remaining points, N represents the number of points, X represents the average value, k represents the slope of the fitting parking space line, and b represents the intercept of the fitting parking space line.

[0026] As a preferred solution of the parking space corner point correction method based on ultrasonic sensor described in the present invention, wherein: the range of the 10 points after the nearest point ID includes finding the nearest point and the 10 points after that, filtering out abnormal points, and according to least squares fitting, if it is the first section of the obstacle, the parking space lines k and b are calculated to determine the left and right positions of the parking space in the vehicle; if it is on the upper right side, x is the largest and y is the smallest, which is the nearest point; if it is on the upper left side, x is the smallest and y is the smallest, which is the parking space corner point; if it is the second section of the obstacle, the x value is opposite to that of the first section; if it is on the upper right side, x takes the opposite rule and y remains unchanged; if it is on the upper left side, x remains unchanged and y takes the opposite rule; if it is on the lower left side, both x and y take the opposite rule.

[0027] As a preferred solution of the parking space corner correction method based on ultrasonic sensor described in the present invention, the range of the 10 points after the nearest point ID includes the beam angle correction calculation based on the coordinates of the nearest point after fitting and filtering and the last 10 points, and the correction formula is:

[0028]

[0029] Among them, x1 represents the coordinates of the corrected corner point, x represents the coordinates of the current obstacle, U represents the ultrasonic detection value of the current obstacle, Umin represents the ultrasonic detection value of the nearest point, and c1, c2, and c3 are calibration values;

[0030]

[0031] Among them, the obstacle is located at x>0, x1 is the calculation formula of the first obstacle coordinates, x2 is the calculation formula of the second obstacle coordinates, and the opposite is true for x<0.

[0032] As a preferred solution of the parking space corner correction method based on ultrasonic sensor described in the present invention, wherein: the influence of the correction beam angle on the ultrasonic data includes, according to the beam angle correction formula, correcting and calculating the coordinate arrays sum1 and sum2 within a certain range near the nearest point, traversing the maximum value of the first obstacle x3 in sum1 and the minimum value of the second obstacle x4 in sum2, and at the same time, comparing the maximum values ​​of x1 and x3, and the minimum values ​​of x2 and x4 as the corner point coordinates output, according to the output x coordinate, taking out the corresponding y coordinate, and outputting the final corner point (x, y)(x', y');

[0033] The final corner point is the corner point with the best parking space among the selected beam angle prediction corner points and the least squares fitting corner points, wherein the first corner point is the maximum value of the first horizontal segment x, and the second corner point is the minimum value rule of the second horizontal segment.

[0034] A computer device includes a memory and a processor, wherein the memory stores a computer program, and is characterized in that when the processor executes the computer program, the steps of a parking space corner correction method based on an ultrasonic sensor are implemented.

[0035] A computer-readable storage medium stores a computer program, wherein the computer program, when executed by a processor, implements the steps of a parking space corner correction method based on an ultrasonic sensor.

[0036] Beneficial effects of the present invention: Based on the beam angle correction formula and filtering algorithm, the present invention obtains an ultrasonic parking space corner correction scheme, which shows that the parking space corner can be predicted by using the beam angle correction formula after filtering the parking space corner ultrasonic data through the probabilistic robot model and Kalman filter. The method assumes that when the parking space ultrasonic data is near the parking space corner, there is a certain relationship between the nearest point and the real corner. By using the beam angle correction formula, the parking space corner can be predicted by the nearest point, thereby correcting the parking space corner position selected only based on the jump, improving the accuracy of parking space corner detection, and avoiding the problem of spatial parking space corner prediction accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0038] Figure 1 A schematic diagram of an algorithm flow of an ultrasonic sensor identifying spatial parking space corner points in a parking space corner point correction method based on an ultrasonic sensor provided in one embodiment of the present invention.

[0039] Figure 2 A specific logic diagram of a parking space corner point correction based on a beam angle of a parking space corner point correction method based on an ultrasonic sensor provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0041] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0042] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0043] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0044] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0045] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] Example 1, reference Figure 1-Figure 2 , which is the first embodiment of the present invention, provides a parking space corner correction method based on an ultrasonic sensor, comprising:

[0047] S1: According to the jump state of ultrasonic radar detection data, the horizontal segments and corner points of the obstacles on the left and right sides of the parking space are obtained.

[0048] S2: Calculate the coordinates of the obstacle based on the data from the two ultrasonic radars on the side of the vehicle.

[0049] S3: Perform Kalman filtering on the ultrasonic obstacle coordinate data to remove noise points in the horizontal section of the obstacle.

[0050] S4: Find the ID of the closest point of the horizontal section of the obstacle near the corrected corner point to the vehicle, and the corresponding ultrasonic data.

[0051] S5: According to the coordinates of the nearest point within a certain range near the corner point and the ultrasonic data, the influence of the beam angle on the ultrasonic data is corrected, and the x, y coordinates corresponding to the corner point are predicted.

[0052] The obstacle coordinate calculation includes using the parking space corner coordinates of the previous frame calculated and corrected using the calculation method of the present process as the obstacle coordinates of the present frame.

[0053] The Kalman filtering of the ultrasonic obstacle coordinate data includes, according to the vehicle running state, including speed, acceleration, heading angle, and the probabilistic robot kinematics model, deriving the vehicle position at the next moment, that is, the state equation:

[0054]

[0055] Add noise as Gaussian white noise back:

[0056]

[0057] Perform coordinate conversion based on the obstacle position in the previous frame and the predicted vehicle position in this frame:

[0058]

[0059] Among them, x', Y', θ' predict the vehicle position and azimuth of the next frame, x, y, θ are the current vehicle position and azimuth, v is the current translation speed, ω is the current rotation speed, and Δt is the time interval;

[0060] After calculating the predicted obstacle position, the difference between the predicted value and the measured value is calculated, and points exceeding 30 cm are filtered out.

[0061] The certain range near the corner point includes the range of 10 points after the nearest point ID.

[0062] The influence of the modified beam angle on the ultrasonic data includes performing least square fitting on the horizontal segment coordinates of the first and second obstacles after filtering, and calculating the spatial parking space corner coordinates (x1, y1), (x2, y2) formed by the combination of the closest point obstacle 1 and obstacle 2 according to the fitting straight lines k and b;

[0063] For the (x, y) coordinates of the 40 points after the nearest point (a, b), calculate the x jump situation of each point before and after, remove the points with a jump of more than 10 cm, and then calculate the xy jump situation every 8 points. If it exceeds 30 cm, update the nearest point to the previous non-jump point before the jump interval, and perform the least squares fitting from the nearest point to the remaining points:

[0064]

[0065] By calculating the coordinates of the nearest point b corresponding to a as the least squares fitting corner coordinates, and calculating the distance from the remaining points to the fitting straight line, according to the distance Filter out points exceeding 30cm;

[0066] Among them, x i ,y i The coordinates of all points from the nearest point to the remaining points, N represents the number of points, X represents the average value, k represents the slope of the fitting parking space line, and b represents the intercept of the fitting parking space line.

[0067] The range of the 10 points after the nearest point ID includes finding the nearest point and the 10 points after that, filtering out abnormal points, and according to the least squares fitting, if it is the first section of the obstacle, the parking space line k, b is calculated to determine the left and right positions of the parking space; if it is on the upper right side, x is the largest and y is the smallest, which is the nearest point; if it is on the upper left side, x is the smallest and y is the smallest, which is the corner point of the parking space; if it is the second section of the obstacle, the x value is opposite to that of the first section, if it is on the upper right side, x takes the opposite rule and y remains unchanged; if it is on the upper left side, x remains unchanged and y takes the opposite rule; if it is on the lower left side, x and y both take the opposite rule.

[0068] The range of the 10 points after the nearest point ID includes the beam angle correction calculation based on the coordinates of the nearest point after fitting and filtering and the last 10 points. The correction formula is:

[0069]

[0070] Among them, x1 represents the coordinates of the corrected corner point, x represents the coordinates of the current obstacle, U represents the ultrasonic detection value of the current obstacle, Umin represents the ultrasonic detection value of the nearest point, and c1, c2, and c3 are calibration values;

[0071]

[0072] Among them, the obstacle is located at x>0, x1 is the calculation formula of the first obstacle coordinates, x2 is the calculation formula of the second obstacle coordinates, and the opposite is true for x<0.

[0073] The influence of the corrected beam angle on the ultrasonic data includes, according to the beam angle correction formula, correcting and calculating the coordinate arrays sum1 and sum2 within a certain range near the nearest point, traversing the maximum value of the first obstacle x3 in sum1 and the minimum value of the second obstacle x4 in sum2, and at the same time, comparing the maximum values ​​of x1 and x3, and the minimum values ​​of x2 and x4 as the corner point coordinates output, and according to the output x coordinate, taking out the corresponding y coordinate, and outputting the final corner point (x, y)(x', y');

[0074] The final corner point is the corner point with the best parking space among the selected beam angle prediction corner points and the least squares fitting corner points, wherein the first corner point is the maximum value of the first horizontal segment x, and the second corner point is the minimum value rule of the second horizontal segment.

[0075] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0076] Example 2

[0077] The second embodiment of the present invention is different from the previous embodiment in that:

[0078] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0079] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0080] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0081] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0082] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0083] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A parking space corner correction method based on ultrasonic sensor, characterized in that: include, According to the jump state of ultrasonic radar detection data, the horizontal segments and corner points of the obstacles on the left and right sides of the parking space are obtained; Calculate the coordinates of the obstacle based on the data from the two ultrasonic radars on the side of the vehicle; Perform Kalman filtering on the ultrasonic obstacle coordinate data to remove noise points in the horizontal section of the obstacle; Find the ID of the closest point of the horizontal section of the obstacle near the corrected corner point to the vehicle, and the corresponding ultrasonic data; According to the coordinates of the nearest point within a certain range near the corner point and the ultrasonic data, the influence of the beam angle on the ultrasonic data is corrected, and the x, y coordinates corresponding to the corner point are predicted.

2. The method for correcting parking space corner points based on ultrasonic sensors according to claim 1, characterized in that: The obstacle coordinate calculation includes using the parking space corner coordinates of the previous frame calculated and corrected using the calculation method of the present process as the obstacle coordinates of the present frame.

3. A parking space corner correction method based on ultrasonic sensor as claimed in claim 2, characterized in that: The Kalman filtering of the ultrasonic obstacle coordinate data includes, according to the vehicle running state, including speed, acceleration, heading angle, and the probabilistic robot kinematics model, deriving the vehicle position at the next moment, that is, the state equation: Add noise as Gaussian white noise back: Perform coordinate conversion based on the obstacle position in the previous frame and the predicted vehicle position in this frame: Among them, x', Y', θ' predict the vehicle position and azimuth of the next frame, x, y, θ are the current vehicle position and azimuth, v is the current translation speed, ω is the current rotation speed, and Δt is the time interval; After calculating the predicted obstacle position, the difference between the predicted value and the measured value is calculated, and points exceeding 30 cm are filtered out.

4. A parking space corner correction method based on ultrasonic sensor as claimed in claim 3, characterized in that: The range near the corner point includes: The range of 10 points after the nearest point ID.

5. A parking space corner correction method based on ultrasonic sensor as claimed in claim 4, characterized in that: The influence of the modified beam angle on the ultrasonic data includes performing least square fitting on the horizontal segment coordinates of the first and second obstacles after filtering, and calculating the spatial parking space corner coordinates (x1, y1), (x2, y2) formed by the combination of the closest point obstacle 1 and obstacle 2 according to the fitting straight lines k and b; For the (x, y) coordinates of the 40 points after the nearest point (a, b), calculate the x jump situation of each point before and after, remove the points with a jump of more than 10 cm, and then calculate the xy jump situation every 8 points. If it exceeds 30 cm, update the nearest point to the previous non-jump point before the jump interval, and perform the least squares fitting from the nearest point to the remaining points: By calculating the coordinates of the nearest point b corresponding to a as the least squares fitting corner coordinates, and calculating the distance from the remaining points to the fitting straight line, according to the distance Filter out points exceeding 30cm; Among them, x i ,y i The coordinates of all points from the nearest point to the remaining points, N represents the number of points, X represents the average value, k represents the slope of the fitting parking space line, and b represents the intercept of the fitting parking space line.

6. A parking space corner correction method based on ultrasonic sensor as claimed in claim 5, characterized in that: The range of the 10 points after the nearest point ID includes finding the nearest point and the 10 points after that, filtering out abnormal points, and according to the least squares fitting, if it is the first section of the obstacle, the parking space line k, b is calculated to determine the left and right positions of the parking space; if it is on the upper right side, x is the largest and y is the smallest, which is the nearest point; if it is on the upper left side, x is the smallest and y is the smallest, which is the corner point of the parking space; if it is the second section of the obstacle, the x value is opposite to that of the first section, if it is on the upper right side, x takes the opposite rule and y remains unchanged; if it is on the upper left side, x remains unchanged and y takes the opposite rule; if it is on the lower left side, x and y both take the opposite rule.

7. A parking space corner correction method based on ultrasonic sensor as claimed in claim 6, characterized in that: The range of the 10 points after the nearest point ID includes the beam angle correction calculation based on the coordinates of the nearest point after fitting and filtering and the last 10 points. The correction formula is: Among them, x1 represents the coordinates of the corrected corner point, x represents the coordinates of the current obstacle, U represents the ultrasonic detection value of the current obstacle, Umin represents the ultrasonic detection value of the nearest point, and c1, c2, and c3 are calibration values; Among them, the obstacle is located at x>0, x1 is the calculation formula of the first obstacle coordinates, x2 is the calculation formula of the second obstacle coordinates, and the opposite is true for x<0.

8. The method for correcting parking space corner points based on ultrasonic sensors according to claim 7, characterized in that: The influence of the corrected beam angle on the ultrasonic data includes, according to the beam angle correction formula, correcting and calculating the coordinate arrays sum1 and sum2 within a certain range near the nearest point, traversing the maximum value of the first obstacle x3 in sum1 and the minimum value of the second obstacle x4 in sum2, and at the same time, comparing the maximum values ​​of x1 and x3, and the minimum values ​​of x2 and x4 as the corner point coordinates output, and according to the output x coordinate, taking out the corresponding y coordinate, and outputting the final corner point (x, y)(x', y'); The final corner point is the corner point with the best parking space among the selected beam angle prediction corner points and the least squares fitting corner points, where the first corner point is the maximum value of the first horizontal segment x, and the second corner point is the minimum value rule of the second horizontal segment.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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