A Docking Charging Pile Method and Device for a Robot

Abstract

The present invention discloses a method and device for a robot to dock with a charging pile. The robot is equipped with a single-line lidar, and a reflector is fixedly installed on the charging pile. The method includes: obtaining real-time laser point cloud, analyzing the data of each reflective point in the laser point cloud, determining the equation of the reflective straight line, obtaining the coordinates of the target end point, and giving the position information of the reflector; determining the position information of the charging pile according to the relative position relationship between the charging pile and the reflector and combining the position information of the reflector; based on the position information of the charging pile, giving the docking path for the robot to dock with the charging pile, and completing the docking between the robot and the charging pile. The present invention realizes the acquisition of the laser point cloud based on the reflector set on the charging pile, reduces the influence generated by the environment during the process of the robot docking with the charging pile, analyzes the reflective points on the laser point cloud to obtain the position of the reflector on the charging pile, and then obtains the position of the charging pile to achieve docking, so as to improve the accuracy of the robot docking with the charging pile.

Description

Technical Field

[0001] The present invention belongs to the technical field of image analysis, and particularly relates to a method and device for a robot to dock with a charging pile. Background Art

[0002] With the development of robot technology, robots are increasingly used in people's production and life, providing efficient and convenient services for people's production and life. In order to improve the working efficiency of robots, robots need to dock with charging piles to achieve autonomous charging.

[0003] Currently, during the matching charging process between a robot and a charging pile, the robot controls the docking of the robot with the charging pile according to the current positioning information through a pile-docking control algorithm. However, when the charging pile is moved or there is a certain deviation in the robot's positioning, it is easy to cause pile-docking failure, resulting in the robot being unable to charge autonomously and ultimately shutting down, affecting normal operation.

[0004] To solve the problem of the robot failing to dock with the charging pile, existing technologies mainly rely on GPS positioning technology, visual recognition technology, and infrared monitoring technology. However, the positioning accuracy of these technologies will be affected to a certain extent in an environment with occlusion or low visibility, which will also cause problems during the process of the robot docking with the charging pile.

[0005] Patent CN113378750A discloses a charging pile docking method, device, computer device, and storage medium. The method is executed by a robot and includes: obtaining an environmental map and generating a travel instruction according to the charging pile position information in the environmental map; if it is determined that the robot has traveled to meet the preset distance range condition, obtaining a depth image and a three-channel color image, and calculating the current pose information of the charging pile according to the depth image and the three-channel color image; determining a docking pose according to the current pose information of the charging pile to dock with the charging pile, which can realize the automatic, accurate, and dynamic docking of the robot with the charging pile.

[0006] How to reduce the influence of the environment on the robot docking with the charging pile and improve the accuracy of the robot docking with the charging pile is a problem that needs to be solved currently. Summary of the Invention

[0007] In view of the defects existing in the above-mentioned prior art, the present invention discloses a method and device for a robot to dock with a charging pile. The robot is equipped with a single-line lidar, and a reflector is fixedly installed on the charging pile. The method includes: acquiring real-time laser point cloud, analyzing the data of each reflective point in the laser point cloud, determining the equation of the reflective straight line, obtaining the coordinates of the target end point, and giving the position information of the reflector; determining the position information of the charging pile according to the relative position relationship between the charging pile and the reflector and combining the position information of the reflector; based on the position information of the charging pile, giving the docking path for the robot to dock with the charging pile, and completing the docking between the robot and the charging pile. The present invention realizes the acquisition of the laser point cloud based on the reflector arranged on the charging pile, analyzes the reflective points on the laser point cloud to obtain the position of the reflector on the charging pile, and further obtains the position of the charging pile to achieve docking. By acquiring the laser point cloud, the influence of the environment during the process of the robot docking with the charging pile is reduced, and the accuracy of the robot docking with the charging pile is improved.

[0008] In a first aspect, the present invention provides a method for a robot to dock with a charging pile, specifically including the following steps:

[0009] Acquire real-time laser point cloud, where the laser point cloud contains the data of each reflective point of the reflector;

[0010] Analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective straight line, obtain the coordinates of the target end point, and give the position information of the reflector;

[0011] Determine the position information of the charging pile according to the relative position relationship between the charging pile and the reflector and combine the position information of the reflector;

[0012] Based on the position information of the charging pile, give the docking path for the robot to dock with the charging pile, and complete the docking between the robot and the charging pile.

[0013] Further, analyzing the data of each reflective point in the laser point cloud, determining the equation of the reflective straight line, obtaining the coordinates of the target end point, and giving the position information of the reflector specifically includes:

[0014] Analyze the laser intensity values of each pixel on the laser point cloud, determine multiple reflective points, and obtain the data of each reflective point;

[0015] Analyze and fit the data of each reflective point to obtain the equation of the reflective straight line;

[0016] Based on the equation of the reflective straight line and combining the position relationship of multiple reflective points, determine the coordinates of the target end point and give the position information of the reflector.

[0017] Further, analyzing and fitting the data of each reflective point to obtain the equation of the reflective straight line specifically includes:

[0018] Based on the data of each reflective point, obtain the coordinate information of each reflective point in the robot coordinate system;

[0019] Perform Hough transform on the coordinate information of each reflective point to obtain the straight line data corresponding to the reflective point in the parameter space;

[0020] According to the multiple straight line data corresponding to multiple reflective points in the parameter space, determine the intersection data between each straight line;

[0021] Based on the intersection data between each straight line, give the parameters of the reflective straight line equation and determine the reflective straight line equation;

[0022] The reflective straight line equation is specifically expressed as:

[0023] ;

[0024] where x is the forward direction of the robot, y is the direction perpendicular to x, and y and x follow the right-hand rule, and k and b are the parameters of the reflective straight line equation respectively.

[0025] Furthermore, based on the reflective straight line equation and combined with the positional relationship of multiple reflective points, determine the target endpoint coordinates and give the position information of the reflector, specifically including:

[0026] Perform comparative analysis on the data of multiple reflective points to give the target endpoint coordinates;

[0027] Based on the target endpoint coordinates, give the reflector coordinates;

[0028] Through the reflective straight line equation, determine the orientation of the reflector, determine the normal vector direction of the reflector, and the normal vector direction of the reflector is specifically expressed as:

[0029] ;

[0030] where is the angle between the normal vector direction of the reflector and the x-axis, and k is the parameter of the reflective straight line equation.

[0031] Furthermore, perform comparative analysis on the data of multiple reflective points to give the target endpoint coordinates, specifically including:

[0032] From the data of multiple reflective points, determine the reflective point with the largest abscissa, the reflective point with the smallest abscissa, the reflective point with the largest ordinate, and the reflective point with the smallest ordinate;

[0033] Based on the reflective point with the largest abscissa and the reflective point with the smallest abscissa, give the maximum abscissa distance;

[0034] Based on the reflective point with the largest ordinate and the reflective point with the smallest ordinate, give the maximum ordinate distance;

[0035] When the maximum vertical distance is less than the maximum horizontal distance, the maximum horizontal reflection point and the minimum horizontal reflection point are used as the target endpoints and the target endpoint coordinates are determined.

[0036] When the maximum vertical distance is greater than or equal to the maximum horizontal distance, the maximum vertical reflection point and the minimum vertical reflection point are used as the target endpoints and the target endpoint coordinates are determined.

[0037] Further, the target endpoint coordinates are specifically expressed as;

[0038]

[0039] Among them, and are the coordinates of two target endpoints, is the coordinate of the reflection point corresponding to the minimum x coordinate among multiple reflection points, is the coordinate of the reflection point corresponding to the maximum x coordinate among multiple reflection points, is the coordinate of the reflection point corresponding to the minimum y coordinate among multiple reflection points, is the coordinate of the reflection point corresponding to the maximum y coordinate among multiple reflection points, is and the distance between two points.

[0040] Further, according to the relative position relationship between the charging pile and the reflector, and in combination with the position information of the reflector, the position information of the charging pile is determined, specifically including:

[0041] Obtain real-time environmental data, analyze the moving position of the robot, and determine the transformation matrix between the robot coordinate system and the fixed coordinate system, where the robot coordinate system is a coordinate system with the position of the robot as the origin;

[0042] Based on the target endpoint coordinates, analyze the midpoint coordinates corresponding to the target endpoint coordinates, and give the reflector coordinates;

[0043] Combined with the transformation matrix between the robot coordinate system and the fixed coordinate system, transform the reflector coordinates to determine the initial position of the reflector, where the initial position of the reflector is specifically expressed as:

[0044]

[0045] Among them, is the initial position of the reflector, M is the transformation matrix from the robot coordinate system to the map coordinate system, is the reflector coordinate;

[0046] According to the relative position relationship between the charging pile and the reflector, adjust the initial position of the reflector to determine the position of the charging pile.

[0047] Further, the coordinates of the reflector are specifically expressed as:

[0048]

[0049] where x is the abscissa of the charging pile in the robot coordinate system, and y is the ordinate of the charging pile in the robot coordinate system. are respectively the abscissas of the target endpoint coordinates in the robot coordinate system. are respectively the ordinates of the target endpoint coordinates in the robot coordinate system.

[0050] Further, the transformation matrix between the robot coordinate system and the fixed coordinate system is determined through the following steps:

[0051] Obtain real-time environmental data, and based on the real-time environmental data, determine the position and attitude changes of the robot in the fixed coordinate system.

[0052] Based on the position and attitude changes of the robot in the fixed coordinate system, combined with the position and attitude of the robot in the robot coordinate system, analyze the translation and rotation information between the robot coordinate system and the fixed coordinate system, and give the transformation matrix.

[0053] Further, according to the relative position relationship between the charging pile and the reflector, adjust the initial position of the reflector to determine the position of the charging pile, which specifically includes the following steps:

[0054] Based on the position of the reflector on the charging pile, give the position difference and angle difference between the reflector and the charging pile in each direction.

[0055] Based on the position difference between the reflector and the charging pile in each direction, adjust the coordinates of the corresponding direction of the initial position of the reflector.

[0056] Based on the angle difference between the reflector and the charging pile in each direction, adjust the angle of the corresponding direction of the initial position of the reflector to determine the position of the charging pile.

[0057] Further, based on the position information of the charging pile, give the docking path for the robot to dock with the charging pile to complete the docking between the robot and the charging pile, which specifically includes the following steps:

[0058] Based on the position information of the charging pile, give the docking path for the robot with the charging pile position as the end point.

[0059] Obtain the charging status of the robot during the docking process, and complete the docking of the charging pile based on the charging status.

[0060] In a second aspect, the present invention also provides a docking charging pile device for a robot, which adopts the docking charging pile method for a robot as described in any one of the above, including:

[0061] A data acquisition module, configured to acquire real-time laser point cloud, wherein the laser point cloud contains data of each reflective point of the reflector;

[0062] A position determination module, configured to analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective straight line, obtain the coordinates of the target end point, and give the position information of the reflector;

[0063] A charging pile determination module, configured to determine the position information of the charging pile according to the relative position relationship between the charging pile and the reflector and in combination with the position information of the reflector;

[0064] A charging pile docking module, configured to give the docking path for the robot to dock with the charging pile based on the position information of the charging pile, and complete the docking of the robot with the charging pile.

[0065] A method and device for a robot to dock with a charging pile provided by the present invention at least include the following beneficial effects:

[0066] Based on the reflector arranged on the charging pile, the acquisition of the laser point cloud is realized, the reflective points on the laser point cloud are analyzed to obtain the position of the reflector on the charging pile, and then the position of the charging pile is obtained to realize docking. By acquiring the laser point cloud, the influence of the environment on the robot docking with the charging pile is reduced, and the accuracy of the robot docking with the charging pile is improved. Description of the Drawings

[0067] Figure 1 It is a flowchart of a method for a robot to dock with a charging pile provided by an embodiment of the present invention;

[0068] Figure 2 It is a schematic diagram of the position relationship between a robot and a charging pile provided by an embodiment of the present invention;

[0069] Figure 3 It is a flowchart of determining the coordinates of the target end point provided by an embodiment of the present invention;

[0070] Figure 4 It is a schematic diagram of determining the coordinates of the target end point provided by an embodiment of the present invention;

[0071] Figure 5 It is a flowchart of determining the equation of the reflective straight line provided by an embodiment of the present invention;

[0072] Figure 6 It is a flowchart of determining the position of the charging pile provided by an embodiment of the present invention;

[0073] Figure 7 It is a flowchart of determining the transformation matrix provided by an embodiment of the present invention;

[0074] Figure 8 It is a flowchart of determining the position of the charging pile provided by an embodiment of the present invention;

[0075] Figure 9 The structural diagram of the charging pile docking device for a robot provided by an embodiment of the present invention.

[0076] 1. Charging pile; 11. Reflector; 12. Charging port; 2. Robot; 21. Single-line lidar; 201. Data acquisition module; 202. Position determination module; 203. Charging pile determination module; 204. Charging pile docking module. Specific implementation manners

[0077] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings of the specification and specific implementation manners. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0078] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "the" and "said" used in the embodiments of the present invention and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. "Plural" generally includes at least two.

[0079] It should also be noted that the term "comprising", "including" or any other variation thereof is intended to cover a non-exclusive inclusion, so that a commodity or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such commodity or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of another identical element in the commodity or device including the said element.

[0080] With the wide application of industrial robots in fields such as logistics, warehousing, and security, the demand for robot charging pile docking application technology is increasing day by day. The positioning accuracy of the mobile robot docking with the charging pile directly affects the charging efficiency and safety. Especially in low-light or low-visibility environments, traditional positioning methods have many limitations. Due to the low automation level of the robot, the matching charging is prone to failure. If the robot cannot be charged in time, it will cause its power to run out, affecting the user experience.

[0081] To solve the problem of the robot failing to dock with the charging pile, the existing technologies mainly rely on GPS positioning technology, visual recognition technology, and infrared detection technology. Among them, the GPS positioning technology is used to achieve the docking of the charging pile by locating the position of the charging pile. The GPS positioning technology is applicable to outdoor environments and can provide positioning services globally. However, the GPS positioning technology has poor positioning accuracy in indoor or occluded environments and is difficult to provide reliable positioning information in low-light or low-visibility environments. The visual recognition technology is used to identify the two-dimensional code on the charging pile to achieve the docking of the charging pile. The visual recognition technology can identify the characteristics of the charging pile and is applicable to complex indoor and outdoor environments. However, in an environment with low visibility, the image recognition effect of the visual recognition technology drops significantly, making it difficult to ensure the positioning accuracy. The infrared detection technology is used to detect the infrared signal of the charging pile to achieve the docking of the charging pile. The infrared recognition technology can identify the relative positions of the robot and the charging pile and is applicable to simple indoor environments. However, the infrared detector device is relatively small and is applicable to small sweeping robots docking with the pile.

[0082] In summary, the current positioning technologies have problems of varying degrees of reduction in positioning accuracy in low-visibility environments and poor adaptability to different environments. At the same time, due to inaccurate positioning, the robot is prone to collisions when approaching the charging pile, increasing potential safety hazards.

[0083] To solve the above problems, the present invention provides a method for a robot to dock with a charging pile. By obtaining and analyzing the laser point cloud based on the reflector on the charging pile, the position of the charging pile is determined, and a docking path is given based on the position of the charging pile, enabling the robot to accurately approach the charging pile and complete the docking. Through the analysis of the laser point cloud, the influence of factors such as light and occlusion in the environment on the determination of the position of the charging pile is reduced, so as to improve the docking accuracy between the robot and the charging pile.

[0084] As Figure 1 shown, the embodiment of the present invention provides a method for a robot to dock with a charging pile, and the specific steps are as follows:

[0085] S101: Obtain the laser point cloud.

[0086] Specifically, the laser point cloud contains the data of each reflection point of the reflector 11, and the laser point cloud is obtained based on the reflector 11 provided on the charging pile 1. A single-line lidar 21 is provided on the robot 2. The single-line lidar 21 emits laser light, and the laser light is refracted on different surfaces and fed back to the robot 2 to obtain the laser point cloud. By installing the reflector 11 on the charging pile 1 and using the single-line lidar 21 on the robot 2 for positioning, high-precision positioning of the charging pile 1 can be achieved in low-light or low-visibility environments.

[0087] Refer to Figure 2, a reflector 11 is provided above the charging port 12 of the charging pile 1, and a single-line lidar 21 is provided on the robot 2. The robot 2 walks along the traveling direction of the robot 2, and the laser emitted by the single-line lidar 21 will be reflected on the reflector 11, thereby obtaining a laser point cloud.

[0088] In the example provided by the present invention, the single-line lidar 21 can achieve object positioning by measuring the shape of the object or the specific reflectivity of the object. Since the shape of the charging pile 1 is not unique in the environment, the positioning is achieved by considering designing a specific reflectivity on the surface of the charging pile 1. The design uses a reflective film pasted on the front surface of the charging pile 1 for the two-dimensional lidar detection of the robot 2, and the position of the charging pile 1 is indirectly located by positioning the position of the reflective film.

[0089] S102: Analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective straight line, obtain the coordinates of the target end point, and give the position information of the reflector.

[0090] Refer to Figure 3 , specifically, analyze the laser intensity values of each pixel on the laser point cloud, determine multiple reflective points, and obtain the data of each reflective point; analyze and fit the data of each reflective point to obtain the equation of the reflective straight line; based on the equation of the reflective straight line and combined with the positional relationship of multiple reflective points, determine the coordinates of the target end point and give the position information of the reflector.

[0091] Furthermore, compare and analyze the data of multiple reflective points to give the coordinates of the target end point. Based on the coordinates of the target end point, give the coordinates of the reflector. Through the equation of the reflective straight line, determine the orientation of the reflector, determine the normal vector direction of the reflector. The normal vector direction of the reflector is specifically expressed as:

[0092]

[0093] Among them, is the angle between the normal vector direction of the reflector and the x-axis, and k is the parameter of the equation of the reflective straight line.

[0094] Furthermore, compare and analyze the data of multiple reflective points to give the coordinates of the target end point, specifically including:

[0095] Determine the reflective point with the largest abscissa, the reflective point with the smallest abscissa, the reflective point with the largest ordinate, and the reflective point with the smallest ordinate from the data of multiple reflective points;

[0096] Based on the reflective point with the largest abscissa and the reflective point with the smallest abscissa, give the maximum abscissa distance;

[0097] Based on the reflective point with the largest ordinate and the reflective point with the smallest ordinate, give the maximum ordinate distance;

[0098] When the maximum vertical distance is less than the maximum horizontal distance, the maximum horizontal reflection point and the minimum horizontal reflection point are used as the target endpoints and the target endpoint coordinates are determined;

[0099] When the maximum vertical distance is greater than or equal to the maximum horizontal distance, the maximum vertical reflection point and the minimum vertical reflection point are used as the target endpoints and the target endpoint coordinates are determined.

[0100] It should be noted that the maximum horizontal reflection point refers to the reflection point with the largest abscissa value among all the reflection point data, the minimum horizontal reflection point refers to the reflection point with the smallest abscissa value among all the reflection point data, the maximum vertical reflection point refers to the reflection point with the largest ordinate value among all the reflection point data, and the minimum vertical reflection point refers to the reflection point with the smallest ordinate value among all the reflection point data. It can be understood that when determining the maximum horizontal reflection point and the minimum horizontal reflection point, it has nothing to do with the vertical size of each reflection point data. Similarly, when determining the maximum vertical reflection point and the minimum vertical reflection point, it has nothing to do with the horizontal size of each reflection point data. Then, there may be a situation where two of the four points are the same reflection point. For example, when the abscissa of a certain reflection point is the minimum value of the abscissa among all the reflection point data, and at the same time the ordinate of this reflection point is the minimum value of the ordinate among all the reflection point data, at this time, the minimum horizontal reflection point and the minimum vertical reflection point are the same reflection point.

[0101] The target endpoint coordinates are specifically expressed as:

[0102]

[0103] Among them, and are the coordinates of two target endpoints, is the coordinate of the reflection point corresponding to the minimum x coordinate among multiple reflection points, is the coordinate of the reflection point corresponding to the maximum x coordinate among multiple reflection points, is the coordinate of the reflection point corresponding to the minimum y coordinate among multiple reflection points, is the coordinate of the reflection point corresponding to the maximum y coordinate among multiple reflection points, is and the distance between the two points.

[0104] is the coordinate of the minimum horizontal reflection point, is the coordinate of the maximum horizontal reflection point, is the coordinate of the minimum vertical reflection point, is the coordinate of the maximum vertical reflection point, is the maximum horizontal distance, is the maximum vertical distance.

[0105] In a specific example, referring to Figure 4 , there are five specular point data: A(1, 2), B(3, 5), C(7, 3), D(2, 1), and E(5, 7). According to the judgment of the coordinate values in the five specular point data, it can be obtained that the specular point with the largest abscissa is C(7, 3), the specular point with the smallest abscissa is A(1, 2), the specular point with the largest ordinate is E(5, 7), and the specular point with the smallest ordinate is D(2, 1).

[0106] Subsequently, the maximum distance of the abscissa can be obtained:

[0107]

[0108] The maximum distance of the ordinate:

[0109]

[0110] Since , the target endpoints are the specular point E(5, 7) with the largest ordinate and the specular point D(2, 1) with the smallest ordinate, that is, p1 = D(2, 1) and p2 = E(5, 7).

[0111] By determining the target endpoints through the above method, compared with directly specifying two points as endpoints, the distribution of all specular points can be considered more comprehensively. By comparing the maximum distances of the abscissa and ordinate to determine the target endpoints, the distribution of all points in two directions can be comprehensively considered, ensuring that the selected endpoints can cover all specular points to the greatest extent and making the determined range more in line with the actual data distribution.

[0112] For different specular point distribution situations, there will be different relationships between the maximum distances of the abscissa and ordinate. This judgment method can adaptively select more appropriate endpoints according to the characteristics of the actual data, rather than fixedly specifying certain points, ensuring the generality and flexibility of the target endpoints.

[0113] Determining the endpoints by the maximum distance can make the boundary of the area containing all specular points more conform to the actual data. Compared with specifying endpoints, it can more accurately describe the distribution range of specular points, reduce the problem of the area being too large or too small caused by improper endpoint selection, and provide a more accurate basis for subsequent data analysis, processing, etc.

[0114] It can be understood that when the 2D lidar scans different reflective surfaces, the obtained specular intensities are different. When the 2D lidar scans the reflector on the charging pile, the specular intensity of the reflector is significantly enhanced compared to the non-reflective flat surface.

[0115] In the example provided by the present invention, based on the analysis of the laser intensity of the reflector and the non-reflector, it is obtained that the laser intensity value of the reflector is basically greater than 1000, and the laser intensity value of the non-reflector is basically less than 600. Therefore, the reflection range is set to [1000, +∞]. That is, by traversing the laser intensity values of each pixel in the laser point cloud, when the laser intensity value is within the reflection range, the pixel point is marked as a reflection point, realizing the extraction of the reflection points.

[0116] Near the charging pile, the laser can only detect one reflector. The proposed laser data of the reflector is converted into point cloud data in the robot coordinate system, and then the point cloud data is fitted into a straight line equation through a straight line fitting function to obtain the reflection straight line equation, which is specifically expressed as:

[0117]

[0118] In the example provided by the present invention, the reflection straight line equation is established in the robot coordinate system. In the robot coordinate system, the position of the robot itself is set as the origin of the coordinate system. For example, the geometric center position of the robot's chassis is used as the origin to determine the reference point of the entire coordinate system for measuring the positions of other points. The forward direction of the robot is set as the positive direction of the x-axis. For example, when the robot moves forward along a straight line, the direction it moves is the positive direction of the x-axis. The y-axis direction is perpendicular to the x-axis and follows the right-hand rule. In the robot coordinate system, the coordinates of the points on the reflector detected by the laser sensor can be used to represent the position of the reflector around the robot.

[0119] Refer to Figure 5 , further, based on the data of each reflection point, the coordinate information of each reflection point in the robot coordinate system is obtained. The Hough transform is performed on the coordinate information of each reflection point to obtain the straight line data corresponding to the reflection points in the parameter space. According to the multiple straight line data corresponding to the multiple reflection points in the parameter space, the intersection data between each straight line is determined. Based on the intersection data between each straight line, the parameters of the reflection straight line equation are given to determine the reflection straight line equation.

[0120] The reflection straight line equation is specifically expressed as:

[0121]

[0122] Among them, x is the forward direction of the robot, y is the direction perpendicular to x, and y and x follow the right-hand rule. k and b are the parameters of the reflection straight line equation respectively.

[0123] In the examples provided by the present invention, the reflective points in the robot coordinate system are mapped to the parameter space through the Hough transform, and the parameter space can be the k-b space or the polar coordinate parameter space. In the k-b space, the parameters k and b of the reflective straight line equation are determined by finding the intersection points of the curves. Specifically, for multiple reflective points in the robot coordinate system , in the k-b space, each point corresponds to a straight line . When multiple points are collinear, the corresponding straight lines in the parameter space will intersect at a point, and the coordinates of this intersection point are the slope k and the intercept b of the fitted straight line.

[0124] The coordinate system where the target endpoint coordinates are located is usually the robot coordinate system. The single-line lidar is installed on the robot, and the endpoint coordinates of the reflective plate point cloud obtained by processing the acquired laser point cloud are the coordinate values in the coordinate system established with the robot itself as the reference origin. These coordinate values describe the position of the reflective plate endpoint relative to the robot and will change with the movement and posture of the robot.

[0125] By analyzing and judging the laser intensity of each pixel in the laser point cloud, the reflective points corresponding to the charging pile reflective plate are extracted, the reflective straight line equation is calculated by the straight line fitting method, and the point cloud data of the two endpoints of the reflective plate, that is, the target endpoint coordinates, are calculated through the endpoint logic.

[0126] S103: Determine the position information of the charging pile according to the relative position relationship between the charging pile and the reflective plate and in combination with the position information of the reflective plate.

[0127] Referring to Figure 6 , specifically, obtain the real-time environmental data, analyze the moving position of the robot, and determine the transformation matrix between the robot coordinate system and the fixed coordinate system, where the robot coordinate system is the coordinate system with the position of the robot as the origin. Based on the target endpoint coordinates, analyze the midpoint coordinates corresponding to the target endpoint coordinates, and give the reflective plate coordinates. Combine the transformation matrix between the robot coordinate system and the fixed coordinate system, transform the reflective plate coordinates, and determine the initial position of the reflective plate. Adjust the initial position of the reflective plate according to the relative position relationship between the charging pile and the reflective plate to determine the position of the charging pile.

[0128] Furthermore, the reflective plate coordinates are specifically expressed as:

[0129]

[0130] where x is the abscissa of the charging pile in the robot coordinate system, y is the ordinate of the charging pile in the robot coordinate system, are respectively the abscissas of the target endpoint coordinates in the robot coordinate system, are respectively the ordinates of the target endpoint coordinates in the robot coordinate system.

[0131] In the example provided by the present invention, the correctness of the currently detected reflector is determined by the reflector length threshold. Specifically, according to the actual size of the reflector, the coordinates of the two target endpoints of the reflector are judged. If the distances of the two target endpoints in the x-direction and y-direction are both less than the size of the reflector in the corresponding direction, the detected reflector is considered correct. If it is correct, based on the coordinates of the target endpoints, the coordinates of the reflector in the robot coordinate system are calculated, and then combined with the transformation matrix, the coordinates of the reflector in the robot coordinate system are transformed into the coordinates in the map coordinate system, and the initial position of the reflector is given.

[0132]

[0133] Among them, is the initial position of the reflector, that is, the coordinates of the reflector in the map coordinate system, M is the transformation matrix from the robot coordinate system to the map coordinate system, is the coordinates of the reflector.

[0134] Furthermore, the transformation matrix between the robot coordinate system and the fixed coordinate system is determined through the following steps:

[0135] Refer to Figure 7 , obtain the real-time environment data, and based on the real-time environment data, determine the position and attitude changes of the robot in the fixed coordinate system. Based on the position and attitude changes of the robot in the fixed coordinate system, combined with the position and attitude of the robot in the robot coordinate system, analyze the translation and rotation information between the robot coordinate system and the fixed coordinate system, and give the transformation matrix.

[0136] In the example provided by the present invention, the fixed coordinate system is the map coordinate system. It should be understood that the map coordinate system is a globally fixed coordinate system, which is used to uniformly represent the positions of objects and the poses of robots in the entire working environment, and provides a global reference framework for the robot. The robot coordinate system changes with the movement and rotation of the robot in the environment, and the position and direction relative to the map coordinate system are constantly changing. The robot determines its own position and attitude in the map coordinate system through its own sensors and algorithms, and at the same time transforms the information it perceives (such as the endpoint coordinates of the reflector, that is, the target endpoint coordinates) into the map coordinate system for global positioning.

[0137] In the example provided by the present invention, the conversion matrix is obtained by using simultaneous localization and mapping (SLAM). The specific process is as follows: During the simultaneous localization and mapping (SLAM) process, the robot uses various sensors such as lidar and inertial measurement unit (IMU) to obtain environmental information, namely real-time environmental data. For example, the lidar scans the surrounding environment to obtain point cloud data, and by matching it with the already constructed map, the pose change of the robot relative to the map is calculated. Through continuous perception and calculation, the robot gradually constructs a map and determines its position and orientation in the map coordinate system, thereby obtaining the conversion matrix from the robot coordinate system to the map coordinate system. Among them, the transformation matrix is represented by a 4*4 homogeneous transformation matrix M, which contains translation and rotation information. In the robot operating system (ROS), the transformation library can conveniently manage and obtain the transformation matrix. The transformation library maintains a coordinate system tree to record the relationships between various coordinate systems, and the robot can obtain the transformation matrix from the robot coordinate system to the map coordinate system by querying the coordinate system tree.

[0138] Since the target endpoint coordinates are obtained in the robot coordinate system, it is necessary to use the conversion matrix M from the robot coordinate system to the map coordinate system to convert the target endpoint coordinates to the map coordinate system. Through matrix multiplication for the conversion, where (x, y) are the coordinates of the endpoint in the robot coordinate system, and are the coordinates after conversion to the map coordinate system. The homogeneous coordinate representation is for the convenience of unified calculation of transformations such as translation and rotation.

[0139] Refer to Figure 8 , further, based on the position of the reflector on the charging pile, the position difference and angle difference between the reflector and the charging pile in each direction are given. Based on the position difference between the reflector and the charging pile in each direction, the coordinates in the corresponding direction of the initial position of the reflector are adjusted. Based on the angle difference between the reflector and the charging pile in each direction, the angle in the corresponding direction of the initial position of the reflector is adjusted to determine the position of the charging pile.

[0140] According to the relative position relationship between the charging pile and the reflector, the initial position of the reflector is adjusted to determine the position of the charging pile, which is specifically expressed as:

[0141]

[0142] Among them, is the abscissa of the initial position of the reflector, is the ordinate of the initial position of the reflector, is the angle of the initial position of the reflector, that is, the orientation angle of the reflector in the map coordinate system, is the abscissa of the charging pile position, is the ordinate of the charging pile position, is the orientation angle of the charging pile position, is the abscissa difference between the charging pile and the reflector in the map coordinate system, is the ordinate difference between the charging pile and the reflector in the map coordinate system, is the orientation angle difference between the charging pile and the reflector in the map coordinate system.

[0143] In the specific example provided by the present invention, is measured when installing the reflector on the charging pile. When installing the reflector on the charging pile, measurement tools (such as rulers, angle measuring instruments, etc.) are used to directly measure the position offset and angle offset of the reflector relative to the charging pile on the horizontal plane. For example, a ruler is used to measure the distance difference between the center of the reflector and the center of the charging pile in the x and y directions, and an angle measuring instrument is used to measure the angle difference between the orientation of the reflector and the orientation of the charging pile.

[0144] The above-mentioned is obtained by the reflecting straight line equation to get the normal vector of the charging pile, and then the coordinate transformation of the normal vector of the charging pile is performed based on the transformation matrix. Among them, the normal vector of the charging pile is specifically expressed as: .

[0145] S104: Based on the position information of the charging pile, give the docking path for the robot to dock with the charging pile to complete the docking between the robot and the charging pile.

[0146] Specifically, based on the position information of the charging pile, give the robot docking path with the charging pile position as the end point. Obtain the charging state of the robot during the docking process and complete the charging pile docking based on the charging state.

[0147] In a specific implementation manner, according to the charging pile position and the relative position relationship between the robot and the pile, the robot's navigation position for docking with the pile is obtained, specifically expressed as:

[0148]

[0149] Among them, is the abscissa of the robot's navigation position for docking with the pile, is the ordinate of the robot's navigation position for docking with the pile, is the orientation angle of the robot's navigation position for docking with the pile, is the relative x coordinate offset from the charging pile position to the navigation position for docking with the pile, The relative y - coordinate offset from the charging pile position to the pile - docking navigation position The heading - coordinate offset from the charging pile position to the pile - docking navigation position.

[0150] When the robot starts to dock with the pile, the robot is already directly in front of the charging pile. It is necessary to plan a straight line from the current position of the robot to the docking position of the charging pile, which is the charging - pile navigation path.

[0151] Control the robot's pile - docking movement according to the charging - pile navigation path. When the robot detects the charging state or reaches the charging - pile navigation position or detects a collision, it is determined that the pile - docking action is completed, and the charging - pile docking is completed.

[0152] The method for a robot to dock with a charging pile provided by the embodiment of the present invention obtains a laser point cloud through a radar laser set on the robot, then judges the laser intensity values of each point in the laser point cloud to obtain a plurality of specular - point data, then analyzes the specular - point data in the robot coordinate system to obtain the specular - line equation and obtain the target - endpoint coordinates. Furthermore, calculate the normal vector of the line and the distance from the robot to the line, adjust the initial position of the specular - reflector according to the relative position relationship between the charging pile and the specular - reflector, and determine the charging - pile position. Plan the pile - docking path based on the charging - pile position and control the robot to complete the pile - docking, so that the robot is in the charging - pile state.

[0153] Referring to Figure 9 , the embodiment of the present invention provides a device for a robot to dock with a charging pile, including:

[0154] A data - acquisition module 201, configured to acquire real - time laser point cloud, where the laser point cloud includes specular - point data of each specular - reflector;

[0155] A position - determination module 202, configured to analyze the specular - point data in the laser point cloud, determine the specular - line equation, obtain the target - endpoint coordinates, and give the position information of the specular - reflector;

[0156] A charging - pile determination module 203, configured to determine the position information of the charging pile according to the relative position relationship between the charging pile and the specular - reflector and in combination with the position information of the specular - reflector;

[0157] A charging - pile docking module 204, configured to give the docking path for the robot to dock with the charging pile based on the position information of the charging pile and complete the docking of the robot with the charging pile.

[0158] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the described modules can refer to the corresponding processes in the foregoing method embodiments, and will not be elaborated herein.

[0159] Although the preferred embodiments of the present invention have been described, additional changes and modifications can be made to these embodiments by those skilled in the art once they learn the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art can make various changes and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. A method for a robot to dock with a charging pile, characterized in that, The robot is equipped with a single-line lidar, and a reflector is fixedly installed on the charging pile. The method specifically includes the following steps: Obtain real-time laser point cloud, where the laser point cloud contains the data of each reflective point of the reflector; Analyze the laser intensity values of each pixel on the laser point cloud, determine multiple reflective points, and obtain the data of each reflective point; Analyze and fit the data of each reflective point to obtain the reflective straight-line equation; Based on the reflective straight-line equation and combined with the positional relationship of multiple reflective points, determine the target endpoint coordinates and give the position information of the reflector, specifically including: Conduct comparative analysis on the data of multiple reflective points to give the target endpoint coordinates. Among them, conducting comparative analysis on the data of multiple reflective points to give the target endpoint coordinates specifically includes: Determine the reflective point with the largest abscissa, the reflective point with the smallest abscissa, the reflective point with the largest ordinate, and the reflective point with the smallest ordinate from the data of multiple reflective points; Based on the reflective point with the largest abscissa and the reflective point with the smallest abscissa, give the maximum abscissa distance; Based on the reflective point with the largest ordinate and the reflective point with the smallest ordinate, give the maximum ordinate distance; When the maximum ordinate distance is less than the maximum abscissa distance, use the reflective point with the largest abscissa and the reflective point with the smallest abscissa as the target endpoints and determine the target endpoint coordinates; When the maximum ordinate distance is greater than or equal to the maximum abscissa distance, use the reflective point with the largest ordinate and the reflective point with the smallest ordinate as the target endpoints and determine the target endpoint coordinates; Based on the target endpoint coordinates, give the coordinates of the reflector; Through the reflective straight-line equation, determine the orientation of the reflector and determine the direction of the normal vector of the reflector; According to the relative positional relationship between the charging pile and the reflector and combined with the position information of the reflector, determine the position information of the charging pile; Based on the position information of the charging pile, give the docking path for the robot to dock with the charging pile and complete the docking of the robot with the charging pile.

2. The method for a robot to dock with a charging pile according to claim 1, wherein Analyze and fit the data of each reflective point to obtain the reflective straight-line equation, specifically including: Based on the data of each reflective point, obtain the coordinate information of each reflective point in the robot coordinate system; Conduct Hough transform on the coordinate information of each reflective point to obtain the straight-line data corresponding to the reflective points in the parameter space; According to the multiple straight-line data corresponding to multiple reflective points in the parameter space, determine the intersection data between each straight line; Based on the intersection data between each straight line, give the parameters of the reflective straight-line equation and determine the reflective straight-line equation; The reflective straight-line equation is specifically expressed as: ； where x is the forward direction of the robot, y is the direction perpendicular to x, and y and x follow the right-hand rule, and k and b are the parameters of the reflective straight-line equation respectively.

3. The method for a robot to dock with a charging pile according to claim 1, wherein, The direction of the normal vector of the reflector is specifically expressed as: ； Among them, is the included angle between the normal vector direction of the reflector and the x-axis, and k is the parameter of the reflected light straight line equation.

4. The method for a robot to dock with a charging pile according to claim 1, wherein, According to the relative positional relationship between the charging pile and the reflector and combined with the position information of the reflector, determine the position information of the charging pile, specifically including: Obtain real-time environmental data, analyze the moving position of the robot, and determine the transformation matrix between the robot coordinate system and the fixed coordinate system, where the robot coordinate system is a coordinate system with the position of the robot as the origin; Based on the target endpoint coordinates, analyze the midpoint coordinates corresponding to the target endpoint coordinates and give the coordinates of the reflector; Convert the coordinates of the reflector using the transformation matrix that combines the robot coordinate system and the fixed coordinate system to determine the initial position of the reflector. Specifically, the initial position of the reflector is expressed as: ； Among them, is the initial position of the reflector, and M is the conversion matrix from the robot coordinate system to the map coordinate system. is the coordinate of the reflector. Adjust the initial position of the reflector based on the relative position relationship between the charging pile and the reflector to determine the position of the charging pile.

5. The method for a robot to dock with a charging pile according to claim 4, characterized in that, The coordinates of the reflector are specifically expressed as: ； Among them, x is the abscissa of the charging pile in the robot coordinate system, and y is the ordinate of the charging pile in the robot coordinate system. They are respectively the abscissas of the target endpoint coordinates in the robot coordinate system. They are respectively the ordinates of the target endpoint coordinates in the robot coordinate system.

6. The method for a robot to dock with a charging pile according to claim 4, wherein, The transformation matrix between the robot coordinate system and the fixed coordinate system is determined through the following steps: Obtain real-time environmental data and, based on the real-time environmental data, determine the position and attitude changes of the robot in the fixed coordinate system; Based on the position and attitude changes of the robot in the fixed coordinate system, combined with the position and attitude of the robot in the robot coordinate system, analyze the translation and rotation information of the robot coordinate system and the fixed coordinate system, and give the transformation matrix.

7. The method for a robot to dock with a charging pile according to claim 4, characterized in that, Adjust the initial position of the reflector based on the relative position relationship between the charging pile and the reflector to determine the position of the charging pile, which specifically includes the following steps: Based on the position of the reflector on the charging pile, give the position differences and angle differences between the reflector and the charging pile in each direction; Based on the position differences between the reflector and the charging pile in each direction, adjust the coordinates of the corresponding direction of the initial position of the reflector; Based on the angle differences between the reflector and the charging pile in each direction, adjust the angles of the corresponding direction of the initial position of the reflector to determine the position of the charging pile.

8. The method for a robot to dock with a charging pile according to claim 1, wherein, Based on the position information of the charging pile, give the docking path for the robot to dock with the charging pile to complete the docking between the robot and the charging pile, which specifically includes the following steps: Based on the position information of the charging pile, give the robot docking path with the charging pile position as the end point; Obtain the charging status of the robot during the docking process and complete the charging pile docking based on the charging status.

9. A docking charging pile device for a robot, characterized in that, Adopt the method for a robot to dock with a charging pile as described in any one of claims 1-8, including: A data acquisition module for acquiring real-time laser point cloud, where the laser point cloud contains the data of each reflecting point of the reflector; A position determination module for analyzing the laser intensity values of each pixel on the laser point cloud to determine multiple reflecting points and obtain the data of each reflecting point; Analyze and fit the data of each reflecting point to obtain the reflecting straight line equation; Based on the reflecting straight line equation and combined with the position relationship of multiple reflecting points, determine the target end point coordinates and give the position information of the reflector, which specifically includes: Compare and analyze the data of multiple reflecting points to give the target end point coordinates. Specifically, comparing and analyzing the data of multiple reflecting points to give the target end point coordinates includes: Determine the reflecting point with the largest abscissa, the reflecting point with the smallest abscissa, the reflecting point with the largest ordinate, and the reflecting point with the smallest ordinate from the data of multiple reflecting points; Based on the reflecting point with the largest abscissa and the reflecting point with the smallest abscissa, give the maximum abscissa distance; Based on the reflecting point with the largest ordinate and the reflecting point with the smallest ordinate, give the maximum ordinate distance; When the maximum ordinate distance is less than the maximum abscissa distance, take the reflecting point with the largest abscissa and the reflecting point with the smallest abscissa as the target end points and determine the target end point coordinates; When the maximum ordinate distance is greater than or equal to the maximum abscissa distance, take the reflecting point with the largest ordinate and the reflecting point with the smallest ordinate as the target end points and determine the target end point coordinates; Based on the target end point coordinates, give the coordinates of the reflector; Determine the orientation of the reflector and the direction of the normal vector of the reflector through the equation of the reflection line; A charging pile determination module, configured to determine the position information of the charging pile according to the relative position relationship between the charging pile and the reflector and in combination with the position information of the reflector; A charging pile docking module, configured to give a docking path for the robot to dock with the charging pile based on the position information of the charging pile, and complete the docking of the robot with the charging pile.

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