Charging pile butt joint method and device for robot

Abstract

The invention discloses a charging pile butt joint method and device for a robot, the robot carries a single-line laser radar, and a reflector is fixedly installed on a charging pile, and the method comprises the steps: obtaining a real-time laser point cloud, analyzing the data of each reflection point in the laser point cloud, determining a reflection linear equation, obtaining the coordinates of a target end point, and carrying out the butt joint of the target end point; the position information of the reflecting plate is given; determining 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; and on the basis of the position information of the charging pile, a docking path for docking the robot with the charging pile is given, and docking of the robot and the charging pile is completed. The laser point cloud is obtained based on the reflector arranged on the charging pile, the influence of the environment in the process that the robot is in butt joint with the charging pile is reduced, 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 achieve butt joint. The effect of improving the accuracy of docking the charging pile by the robot is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of image analysis, and in particular relates to a method and device for docking a charging pile for a robot. 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 be docked with charging piles to realize autonomous charging.

[0003] At present, during the matching charging process between the robot and the charging pile, the robot is controlled to dock with the charging pile according to the current positioning information through the pile control algorithm. However, when the charging pile is moved or the robot positioning has a certain deviation, it is easy to cause the pile to fail, so that the robot cannot charge autonomously and eventually shuts down, affecting normal operation.

[0004] To solve the problem of robot failure in docking with charging piles, 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 environments with obstructions or low visibility, which will also cause problems for the robot in the process of docking with charging piles.

[0005] Patent CN113378750A discloses a charging pile docking method, device, computer equipment and storage medium. The method is executed by a robot, including: obtaining an environmental map, and generating a travel instruction based on the charging pile location information in the environmental map; if it is determined that the travel meets the preset distance range condition, then obtaining a depth image and a three-channel color image, and calculating the current posture information of the charging pile based on the depth image and the three-channel color image; determining the docking posture based on the current posture information of the charging pile to dock with the charging pile, which can realize automatic, accurate and dynamic docking between the robot and the charging pile.

[0006] How to reduce the impact of the environment on the robot docking with the charging pile and improve the accuracy of the robot docking with the charging pile is the current problem that needs to be solved. 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 docking a robot with a charging pile. The robot is equipped with a single-line laser radar, and a reflector is fixedly installed on the charging pile. The method includes: obtaining a real-time laser point cloud, analyzing the data of each reflective point in the laser point cloud, determining the equation of the reflective line, obtaining the coordinates of the target endpoint, 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 of the robot docking with the charging pile, and completing the docking of the robot with the charging pile. The present invention realizes the acquisition of the laser point cloud based on the reflector set on the charging pile, and 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. By obtaining the laser point cloud, the influence of the environment on 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 docking a charging pile for a robot, which specifically comprises the following steps: Obtaining real-time laser point cloud, wherein the laser point cloud includes data of each reflective point of the reflector; Analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective line, obtain the coordinates of the target endpoint, and give the position information of the reflector; 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; Based on the location information of the charging pile, the docking path for the robot to dock with the charging pile is given to complete the docking of the robot and the charging pile.

[0009] Furthermore, the data of each reflective point in the laser point cloud is analyzed to determine the equation of the reflective line, obtain the coordinates of the target endpoint, and give the position information of the reflective plate, including: Analyze the laser intensity value 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, the target endpoint coordinates are determined and the position information of the reflective plate is given.

[0010] Furthermore, the data of each reflective point are analyzed and fitted to obtain the reflective straight line equation, which specifically includes: Based on the data of each reflective point, the coordinate information of each reflective point in the robot coordinate system is obtained; 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; Determine the intersection data between the straight lines according to the plurality of straight line data corresponding to the plurality of reflective points in the parameter space; Based on the intersection data between the straight lines, the parameters of the reflection straight line equation are given to determine the reflection straight line equation; The equation of the reflection line is specifically expressed as: ; Among them, x is the robot's forward direction, 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 reflection line equation respectively.

[0011] Furthermore, based on the reflection line equation and in combination with the positional relationship of multiple reflection points, the target endpoint coordinates are determined to provide the position information of the reflective plate, specifically including: Compare and analyze multiple reflective point data to give the target endpoint coordinates; Based on the target endpoint coordinates, the reflector coordinates are given; The direction of the reflector is determined by the equation of the reflective line, and the direction of the normal vector of the reflector is determined. The normal vector direction of the reflector is specifically expressed as: ; in, is the angle between the normal vector direction of the reflector and the x-axis, and k is the parameter of the reflection line equation.

[0012] Furthermore, the data of multiple reflective points are compared and analyzed to give the target endpoint coordinates, including: Determine the maximum reflective point on the horizontal coordinate, the minimum reflective point on the horizontal coordinate, the maximum reflective point on the vertical coordinate, and the minimum reflective point on the vertical coordinate from the data of the plurality of reflective points; Based on the maximum reflective point on the horizontal axis and the minimum reflective point on the horizontal axis, the maximum distance on the horizontal axis is given; Based on the maximum reflective point of the ordinate and the minimum reflective point of the ordinate, the maximum distance of the ordinate is given; When the maximum distance of the ordinate is less than the maximum distance of the abscissa, the maximum reflective point of the abscissa and the minimum reflective point of the abscissa are taken as target endpoints and the coordinates of the target endpoints are determined; When the maximum distance of the ordinate is greater than or equal to the maximum distance of the abscissa, the maximum reflective point of the ordinate and the minimum reflective point of the ordinate are taken as target endpoints and the coordinates of the target endpoints are determined.

[0013] Furthermore, the target endpoint coordinates are specifically expressed as;

[0014] in, and are the coordinates of the two target endpoints, is the coordinate of the reflective point corresponding to the minimum x-coordinate value among multiple reflective points, is the coordinate of the reflective point corresponding to the maximum x-coordinate among multiple reflective points, is the coordinate of the reflective point corresponding to the minimum y coordinate among multiple reflective points, is the coordinate of the reflective point corresponding to the maximum y coordinate among multiple reflective points, for and The distance between two points.

[0015] 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: Acquire real-time environmental data, analyze the robot's moving position, 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 robot's position as the origin; Based on the target endpoint coordinates, the midpoint coordinates corresponding to the target endpoint coordinates are analyzed to give the reflector coordinates; Combined with the transformation matrix of the robot coordinate system and the fixed coordinate system, the reflector coordinates are transformed to determine the initial position of the reflector, where the initial position of the reflector is specifically expressed as:

[0016] in, 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; 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.

[0017] Furthermore, the coordinates of the reflector are specifically expressed as:

[0018] Among them, x is the horizontal coordinate of the charging pile in the robot coordinate system, and y is the vertical coordinate of the charging pile in the robot coordinate system. are the horizontal coordinates of the target endpoint coordinates in the robot coordinate system, are the ordinates of the target endpoint coordinates in the robot coordinate system.

[0019] Furthermore, the transformation matrix between the robot coordinate system and the fixed coordinate system is determined by the following steps: Acquire real-time environmental data, and determine the position and posture changes of the robot in a fixed coordinate system based on the real-time environmental data; Based on the position and posture changes of the robot in the fixed coordinate system and combined with the position and posture of the robot in the robot coordinate system, the translation and rotation information of the robot coordinate system and the fixed coordinate system are analyzed to give a transformation matrix.

[0020] Further, 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 specifically includes the following steps: 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, adjust the coordinates of the direction corresponding to the initial position of the reflector; Based on the angle difference between the reflector and the charging pile in various directions, the angle of the direction corresponding to the initial position of the reflector is adjusted to determine the position of the charging pile.

[0021] Furthermore, based on the location information of the charging pile, a docking path for the robot to dock with the charging pile is given, and the docking of the robot and the charging pile is completed, which specifically includes the following steps: Based on the location information of the charging pile, a robot docking path with the charging pile as the end point is given; Get the charging status of the robot during the docking process and complete the docking with the charging pile based on the charging status.

[0022] In a second aspect, the present invention further provides a docking charging pile device for a robot, using any of the above docking charging pile methods for a robot, including: A data acquisition module, used to acquire real-time laser point cloud, wherein the laser point cloud includes data of each reflective point of the reflector; The position determination module is used to analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective line, obtain the coordinates of the target endpoint, and give the position information of the reflector; A charging pile determination module, used 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; The charging pile docking module is used to provide a docking path for the robot to dock with the charging pile based on the location information of the charging pile, thereby completing the docking of the robot with the charging pile.

[0023] The present invention provides a method and device for docking a charging pile for a robot, which at least has the following beneficial effects: The laser point cloud is acquired based on the reflective plate set on the charging pile, and the reflective points on the laser point cloud are analyzed to obtain the position of the reflective plate on the charging pile, and then the position of the charging pile is obtained to achieve docking. By acquiring the laser point cloud, the impact 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A flowchart of a method for docking a charging pile for a robot provided in an embodiment of the present invention; Figure 2 A schematic diagram of the positional relationship between the robot and the charging pile provided in an embodiment of the present invention; Figure 3 A flow chart for determining target endpoint coordinates provided by an embodiment of the present invention; Figure 4 A schematic diagram of determining target endpoint coordinates provided by an embodiment of the present invention; Figure 5 A flow chart for determining a reflection straight line equation provided by an embodiment of the present invention; Figure 6 A flowchart for determining the location of a charging pile provided by an embodiment of the present invention; Figure 7 A flow chart for determining a conversion matrix provided by an embodiment of the present invention; Figure 8 A flowchart for determining the location of a charging pile provided by an embodiment of the present invention; Fig. 9 A structural diagram of a docking charging pile device for a robot provided in an embodiment of the present invention.

[0025] 1. Charging pile; 11. Reflector; 12. Charging port; 2. Robot; 21. Single-line laser radar; 201. Data acquisition module; 202. Position determination module; 203. Charging pile determination module; 204. Charging pile docking module. DETAILED DESCRIPTION

[0026] 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 and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0027] 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", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0028] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0029] With the widespread application of industrial robots in logistics, warehousing, security and other fields, the demand for robot charging pile docking application technology is increasing. The positioning accuracy of the docking between the mobile robot and the charging pile directly affects the charging efficiency and safety, especially in low-light or low-visibility environments, where traditional positioning methods have many limitations. Due to the low degree of robot automation, matching charging is prone to failure. If the robot cannot be charged in time, it will run out of power, affecting the user experience.

[0030] To solve the problem of failure of robot docking with charging piles, existing technologies mainly rely on GPS positioning technology, visual recognition technology and infrared detection technology. Among them, GPS positioning technology is used to locate the charging pile position to achieve charging pile docking. GPS positioning technology is suitable for outdoor environments and can provide global positioning services. However, GPS positioning technology has poor positioning accuracy in indoor or blocked environments, and it is difficult to provide reliable positioning information in low light or low visibility environments. Use visual recognition technology to identify the QR code on the charging pile to achieve charging pile docking. Visual recognition technology can identify the characteristics of the charging pile and is suitable for complex indoor and outdoor environments. However, the image recognition effect of visual recognition technology is significantly reduced in low visibility environments, and it is difficult to ensure positioning accuracy. Use infrared detection technology to detect the infrared signal of the charging pile to achieve charging pile docking. Infrared recognition technology can identify the relative position of the robot and the charging pile, which is suitable for simple indoor environments. However, the infrared detector device is relatively small and is suitable for small sweeping robots to dock.

[0031] In summary, the current positioning technology has different degrees of reduced positioning accuracy in low-visibility environments, and has poor adaptability to different environments. At the same time, due to inaccurate positioning, robots are prone to collision when approaching charging piles, increasing safety risks.

[0032] To solve the above problems, the present invention provides a method for docking a robot with a charging pile, which obtains and analyzes a laser point cloud based on a reflector on the charging pile, determines the position of the charging pile, and gives a docking path based on the position of the charging pile, so that the robot can accurately approach the charging pile and complete the docking. By analyzing the laser point cloud, the influence of environmental lighting, occlusion, etc. on the determination of the charging pile position is reduced, thereby improving the docking accuracy of the robot and the charging pile.

[0033] like Figure 1 As shown, an embodiment of the present invention provides a method for docking a charging pile for a robot, and the specific steps are as follows: S101: Obtain laser point cloud.

[0034] Specifically, the laser point cloud contains the data of each reflective point of the reflector 11, and the laser point cloud is obtained based on the reflector 11 set on the charging pile 1. The robot 2 is provided with a single-line laser radar 21, which emits laser light, which is refracted on different surfaces and fed back to the robot 2 to obtain a laser point cloud. By installing the reflector 11 on the charging pile 1 and using the single-line laser radar 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.

[0035] Reference Figure 2 A reflector 11 is arranged above the charging port 12 of the charging pile 1, and a single-line laser radar 21 is arranged on the robot 2. The robot 2 walks along the moving direction of the robot 2, and the laser emitted by the single-line laser radar 21 will be reflected on the reflector 11, and then the laser point cloud is obtained.

[0036] In the example provided by the present invention, the single-line laser radar 21 can locate the object 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, 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 two-dimensional laser radar detection by the robot 2, and indirectly locates the position of the charging pile 1 by locating the position of the reflective film.

[0037] S102: Analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective line, obtain the coordinates of the target endpoint, and provide the position information of the reflective plate.

[0038] Reference Figure 3 Specifically, the laser intensity value of each pixel on the laser point cloud is analyzed, multiple reflective points are determined, and the data of each reflective point is obtained; the data of each reflective point is analyzed and fitted to obtain the reflective straight line equation; based on the reflective straight line equation and combined with the positional relationship of multiple reflective points, the target endpoint coordinates are determined to give the position information of the reflective plate.

[0039] Furthermore, the data of multiple reflective points are compared and analyzed to give the target endpoint coordinates. Based on the target endpoint coordinates, the reflector coordinates are given. The direction of the reflector is determined by the reflective straight line equation, and the normal vector direction of the reflector is determined. The normal vector direction of the reflector is specifically expressed as:

[0040] in, is the angle between the normal vector direction of the reflector and the x-axis, and k is the parameter of the reflection line equation.

[0041] Furthermore, the data of multiple reflective points are compared and analyzed to give the target endpoint coordinates, including: Determine the maximum reflective point on the horizontal axis, the minimum reflective point on the horizontal axis, the maximum reflective point on the vertical axis, and the minimum reflective point on the vertical axis from the data of the plurality of reflective points; Based on the maximum reflective point on the horizontal axis and the minimum reflective point on the horizontal axis, the maximum distance on the horizontal axis is given; Based on the maximum reflective point of the ordinate and the minimum reflective point of the ordinate, the maximum distance of the ordinate is given; When the maximum distance of the ordinate is less than the maximum distance of the abscissa, the maximum reflective point of the abscissa and the minimum reflective point of the abscissa are taken as target endpoints and the coordinates of the target endpoints are determined; When the maximum distance of the ordinate is greater than or equal to the maximum distance of the abscissa, the maximum reflective point of the ordinate and the minimum reflective point of the ordinate are taken as target endpoints and the coordinates of the target endpoints are determined.

[0042] It should be understood that the maximum reflective point on the horizontal axis refers to the reflective point with the largest horizontal coordinate value among all the reflective point data, the minimum reflective point on the horizontal axis refers to the reflective point with the smallest horizontal coordinate value among all the reflective point data, the maximum reflective point on the vertical axis refers to the reflective point with the largest vertical coordinate value among all the reflective point data, and the minimum reflective point on the vertical axis refers to the reflective point with the smallest vertical coordinate value among all the reflective point data. It can be understood that when determining the maximum reflective point on the horizontal axis and the minimum reflective point on the horizontal axis, it is irrelevant to the size of the vertical coordinates of each reflective point data. Similarly, when determining the maximum reflective point on the vertical axis and the minimum reflective point on the vertical axis, it is irrelevant to the size of the horizontal coordinates of each reflective point data. It may happen that two of the four reflective points are the same point. For example, when the horizontal coordinate of a reflective point is the minimum value of the horizontal coordinate among all the reflective point data, and the vertical coordinate of the reflective point is the minimum value of the vertical coordinate among all the reflective point data, at the same time, the reflective point with the minimum horizontal coordinate and the reflective point with the minimum vertical coordinate are the same reflective point.

[0043] The target endpoint coordinates are specifically expressed as:

[0044] in, and are the coordinates of the two target endpoints, is the coordinate of the reflective point corresponding to the minimum x-coordinate value among multiple reflective points, is the coordinate of the reflective point corresponding to the maximum x-coordinate among multiple reflective points, is the coordinate of the reflective point corresponding to the minimum y coordinate among multiple reflective points, is the coordinate of the reflective point corresponding to the maximum y coordinate among multiple reflective points, for and The distance between two points.

[0045] is the coordinate of the minimum reflective point on the horizontal axis, is the coordinate of the maximum reflective point on the horizontal axis, is the coordinate of the minimum reflective point on the ordinate, is the coordinate of the maximum reflective point on the ordinate, is the maximum distance of the horizontal axis, is the maximum distance of the vertical axis.

[0046] In a specific example, referring to Figure 4 , there are five reflective point data A (1, 2), B (3, 5), C (7, 3), D (2, 1), E (5, 7). According to the judgment of the coordinate values ​​in the five reflective point data, it can be obtained that the maximum reflective point of the horizontal coordinate is C (7, 3), the minimum reflective point of the horizontal coordinate is A (1, 2), the maximum reflective point of the vertical coordinate is E (5, 7), and the minimum reflective point of the vertical coordinate is D (2, 1).

[0047] Then we can get the maximum distance of the horizontal axis:

[0048] Maximum distance of vertical coordinate:

[0049] because , so the target endpoints are the maximum reflective point E(5,7) of the ordinate and the minimum reflective point D(2,1) of the ordinate, that is, p1= D(2,1), p2= E(5,7).

[0050] Determining the target endpoint by the above method can more comprehensively consider the distribution of all reflective points compared to directly specifying two points as endpoints. Determining the target endpoint by comparing the maximum distance of the horizontal and vertical coordinates can comprehensively consider the distribution of all points in both directions, ensuring that the selected endpoint can cover all reflective points to the greatest extent, making the determined range more consistent with the actual data distribution.

[0051] Different distribution of reflective points will have different maximum distance relationships between the horizontal and vertical coordinates. This judgment method can adaptively select more appropriate endpoints based on the characteristics of actual data, rather than fixedly specifying certain points, ensuring the universality and flexibility of the target endpoint.

[0052] Determining the endpoints by the maximum distance can make the boundaries of the area containing all reflective points more closely fit the actual data. Compared with specifying endpoints, it can more accurately describe the distribution range of reflective points and reduce the problem of areas being too large or too small due to improper endpoint selection. This can provide a more accurate basis for subsequent data analysis and processing.

[0053] It is understandable that when the two-dimensional laser radar scans different reflective surfaces, the reflection intensity obtained is different. When the two-dimensional laser radar scans the reflective plate on the charging pile, the reflection intensity of the reflective plate is significantly enhanced compared to the plane of the non-reflective plate.

[0054] In the example provided by the present invention, based on the analysis of the laser intensity of the reflector and the laser intensity of the non-reflector, it is concluded that the laser intensity value of the reflector is substantially greater than 1000, and the laser intensity value of the non-reflector is substantially less than 600, so the reflective range is set to [1000, +∞]. That is, the laser intensity value of each pixel in the laser point cloud is traversed, and when the laser intensity value is within the reflective range, the pixel point is marked as a reflective point, thereby realizing the extraction of the reflective point.

[0055] The laser can only detect one reflector near the charging pile. The proposed reflector laser data is converted into point cloud data in the robot coordinate system. Then the point cloud data is fitted into a straight line equation through a straight line fitting function to obtain the reflective straight line equation, which is specifically expressed as:

[0056] In the example provided by the present invention, the equation of the reflective straight line 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, which is used to measure the positions of other points. The forward direction of the robot is set to 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 reflective board detected by the laser sensor can be used to indicate the position of the reflective board around the robot.

[0057] Reference Figure 5 , further, based on the data of each reflective point, the coordinate information of each reflective point in the robot coordinate system is obtained. The coordinate information of each reflective point is subjected to Hough transformation to obtain the line data corresponding to the reflective point in the parameter space. According to the multiple line data corresponding to the multiple reflective points in the parameter space, the intersection data between the lines are determined. Based on the intersection data between the lines, the parameters of the reflective line equation are given to determine the reflective line equation.

[0058] The equation of the reflection line is specifically expressed as:

[0059] Among them, x is the robot's forward direction, 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 reflection line equation respectively.

[0060] In the example provided by the present invention, the reflective points in the robot coordinate system are mapped to the parameter space through Hough transform, and the parameter space can be kb space or polar coordinate parameter space. In kb space, the parameters k and b of the reflective line equation are determined by finding the intersection of the curves. Specifically, for multiple reflective points in the robot coordinate system , in kb space, each point corresponds to a straight line When there are multiple points on a line, the corresponding lines in the parameter space will intersect at one point. The coordinates of this intersection point are It is the slope k and intercept b of the fitted line.

[0061] The coordinate system where the target endpoint coordinates are located is usually the robot coordinate system. The single-line laser radar is installed on the robot, and the reflector point cloud point coordinates obtained by processing the 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 reflector endpoint relative to the robot, and will change with the movement and posture of the robot.

[0062] By analyzing and judging the laser intensity of each pixel in the laser point cloud, the reflective points corresponding to the reflective plate of the charging pile are extracted, the reflective straight line equation is calculated by straight line fitting, and the point cloud data of the two endpoints of the reflective plate, that is, the target endpoint coordinates, are calculated by endpoint logic.

[0063] S103: 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] Reference Figure 6 Specifically, real-time environmental data is acquired, the mobile position of the robot is analyzed, and the transformation matrix between the robot coordinate system and the fixed coordinate system is determined, where the robot coordinate system is a coordinate system with the position of the robot as the origin. Based on the target endpoint coordinates, the midpoint coordinates corresponding to the target endpoint coordinates are analyzed to give the reflector coordinates. Combined with the transformation matrix of the robot coordinate system and the fixed coordinate system, the reflector coordinates are transformed to determine the initial position of the reflector. 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.

[0065] Furthermore, the coordinates of the reflector are specifically expressed as:

[0066] Among them, x is the horizontal coordinate of the charging pile in the robot coordinate system, and y is the vertical coordinate of the charging pile in the robot coordinate system. are the horizontal coordinates of the target endpoint coordinates in the robot coordinate system, are the ordinates of the target endpoint coordinates in the robot coordinate system.

[0067] In the example provided by the present invention, the reflector length threshold is used to determine whether the currently detected reflector is correct. Specifically, the coordinates of the two target endpoints of the reflector are determined according to the actual size of the reflector. If the distances between the two target endpoints in the x direction and the y direction are both smaller than the size of the reflector in the corresponding direction, the detected reflector is considered to be correct. If it is correct, the coordinates of the reflector in the robot coordinate system are calculated based on the coordinates of the target endpoints, and then combined with the conversion matrix, the coordinates of the reflector in the robot coordinate system are converted to the coordinates in the map coordinate system to give the initial position of the reflector.

[0068]

[0069] in, 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 reflector coordinate.

[0070] Furthermore, the transformation matrix between the robot coordinate system and the fixed coordinate system is determined by the following steps: Reference Figure 7 , obtain real-time environmental data, and determine the position and posture changes of the robot in the fixed coordinate system based on the real-time environmental data. Based on the position and posture changes of the robot in the fixed coordinate system, combined with the position and posture 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.

[0071] In the example provided by the present invention, the fixed coordinate system is a 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 position of objects and the position and posture of the robot in the entire working environment, and provides a global reference frame for the robot. As the robot moves and rotates in the environment, the position and direction of the robot coordinate system relative to the map coordinate system are constantly changing. The robot determines its own position and posture in the map coordinate system through its own sensors and algorithms, and also converts the information it perceives (such as the reflector endpoint coordinates, i.e., the target endpoint coordinates) into the map coordinate system for global positioning.

[0072] In the example provided by the present invention, simultaneous localization and mapping (SLAM) is used to obtain the transformation matrix. The specific process is as follows: In the process of simultaneous localization and mapping (SLAM), the robot uses a variety of sensors such as laser radar and inertial measurement unit (IMU) to obtain environmental information, that is, real-time environmental data. For example, the laser radar scans the surrounding environment to obtain point cloud data, and by matching with the constructed map, the robot's posture change relative to the map is calculated. Through continuous perception and calculation, the robot gradually constructs the map and determines its position and posture in the map coordinate system, thereby obtaining the transformation 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 easily manage and obtain the transformation matrix. The transformation library maintains a coordinate system tree to record the relationship between each coordinate system. The robot can obtain the transformation matrix from the robot coordinate system to the map coordinate system by querying the coordinate system tree.

[0073] Since the target endpoint coordinates are obtained in the robot coordinate system, it is necessary to use the transformation matrix M from the robot coordinate system to the map coordinate system to transform the target endpoint coordinates to the map coordinate system. Transformation is performed, where (x, y) is the coordinate of the endpoint in the robot coordinate system, It is the coordinates converted to the map coordinate system. Homogeneous coordinates are used to facilitate the unified calculation of transformations such as translation and rotation.

[0074] Reference 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 of the direction corresponding to 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 of the direction corresponding to the initial position of the reflector is adjusted to determine the position of the charging pile.

[0075] 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:

[0076] in, is the horizontal coordinate 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 horizontal coordinate of the charging pile position, is the ordinate of the charging pile location, is the orientation angle of the charging pile, is the horizontal coordinate difference between the charging pile and the reflector in the map coordinate system, is the difference in ordinate between the charging pile and the reflector in the map coordinate system, is the difference in orientation angles between the charging pile and the reflector in the map coordinate system.

[0077] In the specific example provided by the present invention, It is measured when the reflector is installed on the charging pile. When the reflector is installed on the charging pile, use a measuring tool (such as a ruler, an angle meter, etc.) to directly measure the position offset and angle offset of the reflector relative to the charging pile on the horizontal plane. For example, use a ruler 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 use an angle meter to measure the angle difference between the direction of the reflector and the direction of the charging pile.

[0078] Above The normal vector of the charging pile is obtained by using the equation of the reflected straight line, and then the normal vector of the charging pile is transformed into the coordinate system based on the transformation matrix. The normal vector of the charging pile is specifically expressed as: .

[0079] S104: Based on the location information of the charging pile, a docking path for the robot to dock with the charging pile is given to complete the docking of the robot with the charging pile.

[0080] Specifically, based on the location information of the charging pile, a robot docking path with the charging pile location as the end point is given. The charging state of the robot during the docking process is obtained, and the charging pile docking is completed based on the charging state.

[0081] In a specific implementation, the navigation position of the robot to the charging pile is obtained according to the position of the charging pile and the relative position relationship between the robot and the pile, which is specifically expressed as:

[0082] in, is the horizontal coordinate of the robot’s navigation position on the pile, is the vertical coordinate of the robot’s navigation position to the pile, is the robot's orientation angle to the pile navigation position, is the relative x-coordinate offset from the charging pile position to the navigation position of the charging pile. is the relative y coordinate offset from the charging pile position to the navigation position of the charging pile, It is the heading coordinate offset from the charging pile position to the navigation position of the charging pile.

[0083] When the robot starts to dock with the charging pile, it is already in front of the charging pile. It is necessary to plan a straight line from the robot's current position to the charging pile docking position, which is the charging pile navigation path.

[0084] The robot is controlled to move toward the charging pile according to the navigation path of the charging pile. When the robot detects the charging status or reaches the navigation position of the charging pile or detects a collision, it is judged that the action toward the charging pile is completed and the charging pile docking is completed.

[0085] The method for docking a robot with a charging pile provided in an embodiment of the present invention obtains a laser point cloud through a radar laser set on the robot, and then judges the laser intensity value of each point in the laser point cloud to obtain multiple reflective point data, and then analyzes the reflective point data in the robot coordinate system to obtain the reflective straight line equation and the target endpoint coordinates. Then, the normal vector of the straight line and the distance from the robot to the straight line are calculated, and the initial position of the reflector is adjusted according to the relative position relationship between the charging pile and the reflector to determine the position of the charging pile. The charging pile docking path is planned based on the charging pile position, and the robot is controlled to complete the docking so that the robot is in the charging pile state.

[0086] Reference Fig. 9 , an embodiment of the present invention provides a docking charging pile device for a robot, comprising: The data acquisition module 201 is used to acquire a real-time laser point cloud, wherein the laser point cloud includes data of each reflective point of the reflector; The position determination module 202 is used to analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective line, obtain the coordinates of the target endpoint, and provide the position information of the reflective plate; The charging pile determination module 203 is used 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; The charging pile docking module 204 is used to provide a docking path for the robot to dock with the charging pile based on the location information of the charging pile, so as to complete the docking of the robot with the charging pile.

[0087] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the described module can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0088] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications 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 equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for docking a charging pile for a robot, characterized in that: The robot is equipped with a single-line laser radar, and a reflector is fixed on the charging pile. The method specifically includes the following steps: Obtaining real-time laser point cloud, wherein the laser point cloud includes data of each reflective point of the reflector; Analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective line, obtain the coordinates of the target endpoint, and give the position information of the reflector; 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; Based on the location information of the charging pile, the docking path for the robot to dock with the charging pile is given to complete the docking of the robot and the charging pile.

2. The method for docking a charging pile for a robot according to claim 1, characterized in that: Analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective line, obtain the coordinates of the target endpoint, and give the position information of the reflector, including: Analyze the laser intensity value 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, the target endpoint coordinates are determined and the position information of the reflective plate is given.

3. The method for docking a charging pile for a robot according to claim 2, characterized in that: The data of each reflective point are analyzed and fitted to obtain the reflective straight line equation, which specifically includes: Based on the data of each reflective point, the coordinate information of each reflective point in the robot coordinate system is obtained; 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; Determine the intersection data between the straight lines according to the plurality of straight line data corresponding to the plurality of reflective points in the parameter space; Based on the intersection data between the straight lines, the parameters of the reflection straight line equation are given to determine the reflection straight line equation; The equation of the reflection line is specifically expressed as: ； Among them, x is the robot's forward direction, 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 reflection line equation respectively.

4. The method for docking a charging pile for a robot according to claim 3, characterized in that: Based on the reflective straight line equation and combined with the positional relationship of multiple reflective points, the target endpoint coordinates are determined and the position information of the reflector is given, including: Comparing and analyzing the data of multiple reflective points to provide the target endpoint coordinates, wherein comparing and analyzing the data of multiple reflective points to provide the target endpoint coordinates specifically includes: Determine the maximum reflective point on the horizontal axis, the minimum reflective point on the horizontal axis, the maximum reflective point on the vertical axis, and the minimum reflective point on the vertical axis from the data of the plurality of reflective points; Based on the maximum reflective point on the horizontal axis and the minimum reflective point on the horizontal axis, the maximum distance on the horizontal axis is given; Based on the maximum reflective point of the ordinate and the minimum reflective point of the ordinate, the maximum distance of the ordinate is given; When the maximum distance of the ordinate is less than the maximum distance of the abscissa, the maximum reflective point of the abscissa and the minimum reflective point of the abscissa are taken as target endpoints and the coordinates of the target endpoints are determined; When the maximum distance of the ordinate is greater than or equal to the maximum distance of the abscissa, the maximum reflective point of the ordinate and the minimum reflective point of the ordinate are taken as the target endpoints and the coordinates of the target endpoints are determined; Based on the target endpoint coordinates, the reflector coordinates are given; The direction of the reflector is determined by the reflection line equation, and the direction of the normal vector of the reflector is determined. The normal vector direction of the reflector is specifically expressed as: ； in, is the angle between the normal vector direction of the reflector and the x-axis, and k is the parameter of the reflection line equation.

5. The method for docking a charging pile for a robot according to claim 1, characterized in that: 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: Acquire real-time environmental data, analyze the robot's moving position, 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 robot's position as the origin; Based on the target endpoint coordinates, the midpoint coordinates corresponding to the target endpoint coordinates are analyzed to give the reflector coordinates; Combined with the transformation matrix of the robot coordinate system and the fixed coordinate system, the reflector coordinates are transformed to determine the initial position of the reflector, where the initial position of the reflector is specifically expressed as: ； in, 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; 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.

6. The method for docking a charging pile for a robot according to claim 5, characterized in that: The coordinates of the reflector are specifically expressed as: ； Among them, x is the horizontal coordinate of the charging pile in the robot coordinate system, and y is the vertical coordinate of the charging pile in the robot coordinate system. are the horizontal coordinates of the target endpoint coordinates in the robot coordinate system, are the ordinates of the target endpoint coordinates in the robot coordinate system.

7. The method for docking a charging pile for a robot according to claim 5, characterized in that: The transformation matrix between the robot coordinate system and the fixed coordinate system is determined by the following steps: Acquire real-time environmental data, and determine the position and posture changes of the robot in a fixed coordinate system based on the real-time environmental data; Based on the position and posture changes of the robot in the fixed coordinate system and combined with the position and posture of the robot in the robot coordinate system, the translation and rotation information of the robot coordinate system and the fixed coordinate system are analyzed to give a transformation matrix.

8. The method for docking a charging pile for a robot according to claim 5, characterized in that: 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 specifically includes the following steps: 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, adjust the coordinates of the direction corresponding to the initial position of the reflector; Based on the angle difference between the reflector and the charging pile in various directions, the angle of the direction corresponding to the initial position of the reflector is adjusted to determine the position of the charging pile.

9. The method for docking a charging pile for a robot according to claim 1, characterized in that: Based on the location information of the charging pile, a docking path for the robot to dock with the charging pile is given to complete the docking of the robot and the charging pile, which specifically includes the following steps: Based on the location information of the charging pile, a robot docking path with the charging pile as the end point is given; Get the charging status of the robot during the docking process and complete the docking with the charging pile based on the charging status.

10. A docking charging pile device for a robot, characterized in that: A method for docking a charging pile for a robot as claimed in any one of claims 1 to 9, comprising: A data acquisition module, used to acquire real-time laser point cloud, wherein the laser point cloud includes data of each reflective point of the reflector; The position determination module is used to analyze the data of each reflective point in the laser point cloud, determine the equation of the reflective line, obtain the coordinates of the target endpoint, and give the position information of the reflector; A charging pile determination module, used 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; The charging pile docking module is used to provide a docking path for the robot to dock with the charging pile based on the location information of the charging pile, thereby completing the docking of the robot with the charging pile.

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