Repeated positioning accuracy test device and test method for a mining robot

Abstract

The present invention relates to a repeated positioning accuracy testing device and testing method for an excavation robot, including an excavation robot, which includes a turntable, a boom, an arm, and a bucket. The turntable, boom, arm, and bucket are connected in series in sequence. The device further includes a target, a scale, a host computer, and a camera component. The target is detachably fixed on the bucket. The scale is vertically fixed on the horizontal ground and is located in front of the bucket. The imaging plane of the camera component is parallel to the plane where the target is located, and the camera component is connected to the host computer. The host computer controls the excavation robot to repeatedly perform the same motion trajectory multiple times, and a combined calibration is carried out using the scale and the camera component to achieve non-contact measurement of the repeated positioning accuracy in the operation plane direction. Compared with the prior art, the present invention has the advantages of convenient operation, low cost, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of precision measurement, and particularly to a device and method for testing the repeat positioning accuracy of an excavation robot. Background Art

[0002] An excavation robot is a construction machinery that can achieve automatic control and intelligent perception after robotizing a traditional excavator. Due to its ability to adapt to extremely harsh environments, it has broad application prospects in multiple fields such as construction, disaster relief, agricultural production, and resource extraction.

[0003] Repeat positioning accuracy is an important performance index for measuring the ability of a robot to repeatedly reach the same position in space. In order to achieve high-precision control of the robot, the measurement of repeat positioning accuracy is an essential step.

[0004] Chinese Patent CN106546270A discloses a robot positioning accuracy tester and a contact measurement method. The tester includes a test body, a support frame, and a standard test ball. The test body includes five contact sensors for measurement, and the axes of the five contact sensors intersect at a point; the support frame is connected to the bottom of the test body for supporting and fixing the test body.

[0005] For large and medium-sized excavation robots, due to their large spatial volume, the repeat positioning accuracy cannot be directly measured manually. At the same time, although the commonly used repeat positioning accuracy measurement equipment has high accuracy, its structural complexity is high, the price is high, and the operation difficulty for personnel is large. Summary of the Invention

[0006] The purpose of the present invention is to overcome the defects of the existing technology that although the repeat positioning accuracy measurement equipment has high accuracy, its structural complexity is high, the price is high, and the operation difficulty for personnel is large, and to provide a device and method for testing the repeat positioning accuracy of an excavation robot.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] A device for testing the repeat positioning accuracy of an excavation robot includes an excavation robot, the excavation robot includes a turntable, a boom, an arm, and a bucket, the turntable, the boom, the arm, and the bucket are connected in series in sequence, the device further includes a target, a scale, a host computer, and a camera component; the target is detachably fixed on the bucket, the scale is vertically fixed on the horizontal ground, the scale is located in front of the bucket, the camera plane of the camera component is parallel to the plane where the target is located, and the camera component is connected to the host computer.

[0009] Further, the host computer includes a control module and an image processing module; the control module is used to receive the sensor information of the excavation robot and output a control signal to the excavation robot to control the working device of the excavation robot to move along a predetermined trajectory; the image processing module receives the position information of the target captured by the camera component and extracts the center coordinates of the target to display the movement trajectory of the bucket in real time.

[0010] Further, the material of the target is acrylic board, and the surface of the target is sprayed with red paint.

[0011] Further, a metal rivet is provided at the center position of the target, the metal rivet penetrates the target, and the metal rivet is adsorbed on the bucket by a strong magnet.

[0012] Further, a white square paper is provided between the target and the bucket, and the area of the white square paper is larger than the area of the target.

[0013] This solution also provides a test method for the repeated positioning accuracy of an excavation robot. The test method includes the following steps:

[0014] S1: Calibrate the internal parameters, external parameters and distortion coefficients of the camera component; plan the trajectory during the positioning process of the excavation robot to determine the reference trajectory;

[0015] S2: The host computer controls the excavation robot to move along the reference trajectory and records the control sequence of the reference trajectory;

[0016] S3: The camera component captures the real-time movement process of the bucket and transmits the captured result to the image processing module to obtain the physical coordinates of the center of the target;

[0017] S4: Record the center coordinates of the target and the position reading of the scale when the excavation robot moves to the positioning point, and record this set of data as the reference group;

[0018] S5: After completing the recording of the reference group data, the excavation robot repeats the movement along the reference trajectory of the reference group multiple times, and records the center coordinates of the target and the position reading of the scale when the excavation robot moves to the positioning point. The data after the reference group is recorded as the measurement group;

[0019] S6: Calculate the repeated positioning accuracy of the excavation robot in the working plane according to the data of the reference group and the measurement group.

[0020] Further, in step S1, the internal parameters, external parameters and distortion parameters of the camera component are calibrated by the Zhang calibration method to determine the position mapping relationship between the image pixel coordinate system and the world coordinate system of the bucket plane of the excavation robot. The specific calibration process of the camera component parameters is as follows:

[0021] Fix a calibration board of known size in the plane of the bucket. The host computer controls the bucket of the excavation robot to move to different positions, and the fixed camera component takes 20 sets of checkerboard images at different angles.

[0022] Detect the feature points of the checkerboard images, determine the pixel coordinate values of the feature points, and calculate the physical coordinate values of the feature points in the world coordinate system according to the known size of the checkerboard calibration board.

[0023] Solve the internal and external parameters and distortion coefficients of the camera component according to the above measurement data and calibration calculation model: establish the position mapping relationship between the pixel coordinate system and the physical coordinate system by solving the homography matrix H, and then the internal and external parameters and distortion coefficients of the camera can be solved, and the L-M algorithm is used to optimize the camera calibration parameters.

[0024] The spatial mapping relationship between the world coordinate system and the pixel coordinate system of the checkerboard is described as:

[0025]

[0026] where u and v represent the coordinates in the pixel coordinate system, and x w , y w represent the coordinates in the world coordinate system.

[0027] The homography matrix is described as:

[0028]

[0029] where s represents the scale factor, f x , f y , γ, u0, v0 represent the 5 internal parameters of the camera, and r1, r2, t represent the external parameters of the camera.

[0030] Further, the trajectory shape in step S1 is a parabola, and a fifth-degree polynomial is used for trajectory planning to ensure the smoothness of the reference trajectory. The speed and acceleration of the reference trajectory at the starting point and the positioning point are both set to zero, and the trajectory formula is specifically described as:

[0031]

[0032] where the pose of the excavation robot at the starting point is the pose of the excavation robot at the positioning point is Point P is the vertex of the parabola, and the coordinates are (h, k).

[0033] Further, the specific process of step S3 is:

[0034] The camera component captures the motion process of the working device of the excavation robot in real time. The image processing module of the upper computer extracts the contour of the target image, uses the Hough transform to determine the center position of the target, and displays the center trajectory in real time. The bucket trajectory is determined through the center trajectory; through the homography matrix, the pixel coordinates of the target center are converted into physical coordinates in the world coordinate system.

[0035] Further, the specific process of step S6 is as follows:

[0036] By calculating the extreme value of the relative position error of the scale data between the measurement group and the reference group, the repeat positioning accuracy of the scale measurement is determined; by calculating the extreme value of the relative position error of the target center between the measurement group and the reference group, the repeat positioning accuracy of the camera component measurement is determined;

[0037] The relative position error E of the target center i can be described as:

[0038]

[0039] where the physical coordinates of the target center of the reference group are (x w0 , y w0 , 0), and the physical coordinates of the target center of the i-th measurement group are (x wi , y wi , 0).

[0040] Compared with the prior art, the present invention has the following advantages:

[0041] (1) In this solution, a target is set on the bucket of the excavation robot, and the movement trajectory of the bucket, that is, the movement trajectory of the target, is captured by the camera component, and the captured image is uploaded to the image processing module in the upper computer to obtain the physical coordinates corresponding to the image coordinates at the target center, that is, the bucket. Combining the acquisition of scale data, the measurement of the repeat positioning accuracy of the excavation robot is realized. The structure of the measuring device is simple, the measuring device is easy to install, the measuring cost is low and the practicability is strong; at the same time, the non-contact measuring method composed of the image and the scale can more conveniently realize the measurement of the repeat positioning accuracy of the larger excavation robot, and the applicable range is wider.

[0042] (2) In this solution, red paint is sprayed on the surface of the target to distinguish the color of the target from the colors of other parts of the excavation robot, making it easier for the camera component to identify the target. At the same time, a square paper with a larger area is set below the target, which further facilitates the identification of the target by the camera component and the extraction of relevant data.

[0043] (3) In this solution, when collecting data of the measurement group, multiple groups of measurement group data are collected, and then compared and calculated with the reference group, which improves the accuracy of the repeated positioning accuracy measurement of the excavation robot. Moreover, the process of this measurement method is simple and the test efficiency is high. Description of the Drawings

[0044] Figure 1 It is a schematic structural diagram of the test device provided by the present invention;

[0045] Figure 2 It is a reference trajectory diagram of the positioning process of the excavation robot provided by the present invention;

[0046] Figure 3 It is a flow chart for extracting the physical coordinates of the target center provided by the present invention;

[0047] Figure 4 It is a simplified diagram of the DH coordinate system of the excavation robot provided by the present invention;

[0048] In the figure: 1, turntable; 2, boom; 3, arm; 4, bucket; 5, white square paper; 6, target; 7, scale; 8, upper computer; 9, camera component. Detailed Embodiments

[0049] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0050] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the present invention claimed, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0051] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0052] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invention product is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation on the present invention.

[0053] It should be noted that the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0054] In addition, terms such as "horizontal" and "vertical" do not mean that the components are required to be absolutely horizontal or hanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0055] Embodiment 1

[0056] This embodiment provides a device for testing the repeat positioning accuracy of an excavation robot, as Figure 1 shown, which includes an excavation robot. The excavation robot includes a turntable 1, a boom 2, an arm 3, and a bucket 4. The turntable 1, the boom 2, the arm 3, and the bucket 4 are connected in series in sequence. The device further includes a target 6, a scale 7, a host computer 8, and a camera component 9. The target 6 is detachably fixed on the bucket 4. The scale 7 is vertically fixed on the horizontal ground. The scale 7 is located in front of the bucket 4. The imaging plane of the camera component 9 is parallel to the plane where the target 6 is located. The camera component 9 is connected to the host computer 8.

[0057] In this embodiment, the traditional excavator is robotized. The traditional hydraulic system is replaced with an electro-hydraulic servo system. A displacement sensor is added to detect the displacement of the oil cylinder, and a motion controller is added as the core processor of the control system. The transformed excavation robot can achieve automatic control and can be remotely wirelessly controlled through the host computer 8.

[0058] The host computer 8 includes a control module and an image processing module. The control module is used to receive the sensor information of the excavation robot and output a control signal to the excavation robot to control the working device of the excavation robot to move along a predetermined trajectory. The image processing module receives the position information of the target 6 captured by the camera component 9 and extracts the center coordinates of the target 6 to display the motion trajectory of the bucket 4 in real time.

[0059] The material of the target 6 is acrylic board, and the surface of the target 6 is sprayed with red paint. A metal rivet is provided at the center position of the target 6, the metal rivet penetrates the target 6, and the metal rivet is adsorbed on the bucket 4 by a strong magnet. A white square paper 5 is provided between the target 6 and the bucket 4, and the area of the white square paper 5 is larger than the area of the target 6.

[0060] In this solution, by spraying red paint on the surface of the target 6, the color of the target 6 is distinguished from the colors of other parts of the excavation robot, making it easier for the imaging component 9 to identify the target 6. At the same time, a square paper with a larger area is set below the target 6, further facilitating the imaging component 9 to identify the target and extract relevant data.

[0061] This embodiment also provides a test method for the repeated positioning accuracy of an excavation robot. The test method includes the following steps:

[0062] S1: Calibrate the internal parameters, external parameters, and distortion coefficients of the imaging component 9; plan the trajectory during the positioning process of the excavation robot to determine the reference trajectory;

[0063] S2: The host computer controls the excavation robot to move along the reference trajectory and records the control sequence of the reference trajectory;

[0064] S3: The imaging component 9 captures the real-time movement process of the bucket 4 and transmits the captured result to the image processing module to obtain the physical coordinates of the center of the target;

[0065] S4: Record the center coordinates of the target 6 and the position reading of the scale 7 when the excavation robot moves to the positioning point, and record this set of data as the reference group;

[0066] S5: After completing the recording of the reference group data, the excavation robot repeats the movement along the reference trajectory of the reference group multiple times, and records the center coordinates of the target 6 and the position reading of the scale 7 when the excavation robot moves to the positioning point. The data after the reference group is recorded as the measurement group;

[0067] S6: Calculate the repeated positioning accuracy of the excavation robot in the working plane according to the data of the reference group and the measurement group.

[0068] In step S1, the internal parameters, external parameters, and distortion parameters of the imaging component 9 are calibrated by the Zhang calibration method to determine the position mapping relationship between the image pixel coordinate system and the world coordinate system of the plane of the bucket 4 of the excavation robot.

[0069] The specific calibration process of the imaging component 9 is as follows:

[0070] Fix a calibration board with a known size within the plane of the bucket 4. The upper computer 8 controls the bucket 4 of the excavation robot to move to different positions, and the fixed camera component 9 captures 20 sets of checkerboard images at different angles.

[0071] Detect the feature points of the checkerboard images, determine the pixel coordinate values of the feature points, and calculate the physical coordinate values of the feature points in the world coordinate system according to the known size of the checkerboard calibration board.

[0072] Solve the internal and external parameters and distortion coefficients of the camera component 9 based on the above measurement data and calibration calculation model: establish the position mapping relationship between the pixel coordinate system and the physical coordinate system by solving the homography matrix H, and then the internal and external parameters and distortion coefficients of the camera can be solved. Use the L-M (Levenberg-Marquardt) algorithm to optimize the camera calibration parameters.

[0073] The spatial mapping relationship between the world coordinate system and the pixel coordinate system of the checkerboard can be described as:

[0074]

[0075] where u and v represent the coordinates in the pixel coordinate system, and x w , y w represent the coordinates in the world coordinate system.

[0076] The homography matrix can be described as:

[0077]

[0078] where s represents the scale factor, f x , f y , γ, u0, v0 represent the 5 internal parameters of the camera, and r1, r2, t represent the external parameters of the camera.

[0079] During the actual operation process, the turntable 1 of the excavation robot does not move, so the rotational motion is not considered. The working device of the excavation robot is always in the same plane, so the plane where the bucket 4 is located is selected as the plane where the physical coordinate system Z W = 0. In this embodiment, the calibration board uses a checkerboard calibration board with the model GP400 12*9.

[0080] In step S1, the trajectory shape is a parabola, and a fifth-degree polynomial is used for trajectory planning to ensure the smoothness of the reference trajectory. The speed and acceleration of the reference trajectory at the starting point and the positioning point are both set to zero. The trajectory formula can be specifically described as:

[0081]

[0082] where the pose of the excavation robot at the starting point is The pose of the excavation robot at the positioning point is Point P is the vertex of the parabola, and its coordinates are (h, k).

[0083] In this embodiment, flat ground and trench-digging operations are selected as references, and the movement process of the excavation robot returning from the operation end point to the operation start point is used as the reference trajectory. The trajectory shape of the reference trajectory in the Cartesian space is designed as a parabola. As Figure 2 The figure shows the reference trajectory diagram of the excavation robot positioning process, where point A is the start point of the positioning process and point B is the positioning point.

[0084] In step S2 of this embodiment, the control module in the upper computer 8 programs and controls the end of the bucket 4 of the excavation robot to move from the initial point to the positioning point according to the reference trajectory. The upper computer 8 records the control quantity sent to the controller at each sampling moment in real time, and saves the control sequence after the recording is completed.

[0085] The specific process of step S3 of this embodiment is as follows: The imaging component 9 captures the movement process of the working device of the excavation robot in real time. The image processing module of the upper computer 8 extracts the contour of the target 6 image, uses the Hough transform to determine the center position of the target 6, and displays the center trajectory in real time, and determines the bucket 4 trajectory through the center trajectory; through the homography matrix, the pixel coordinates of the center of the target 6 are converted into physical coordinates in the world coordinate system. Specifically, in this implementation, the center coordinates of the target 6 and the position reading of the scale 7 are both reserved to one decimal place. As Figure 3 The figure shows the extraction flow chart of the physical coordinates of the center of the target 6.

[0086] The specific process of the measurement group data is as follows: First, move the end of the bucket 4 of the excavation robot to the initial point of the first group of trajectories, and at the same time ensure that the initial displacements of the three oil cylinders of the boom 2, the arm 3 and the bucket 4 are the same as those of the reference group. Then, the control quantity sequence recorded in the reference group is sent to the controller of the excavation robot in turn. The excavation robot moves according to the first group of reference trajectories. Repeat the experiment multiple times and record the center coordinates of the target 6 and the position reading of the scale 7 every time the excavation robot moves to the positioning point. In this embodiment, the controller of the excavation robot uses CAN communication for data transmission, and the control quantity sequence is sent to the controller by the upper computer 8 at a transmission frequency of 10 ms. The main work done by the upper computer 8 in this process is to simulate the data of the excavator handle and transmit data to the controller through CAN communication to realize the reproduction of the actions of the excavation robot.

[0087] The specific process of step S6 is as follows: Determine the repeat positioning accuracy measured by the scale 7 by calculating the extreme value of the relative position error between the measurement group and the reference group of scale data; determine the repeat positioning accuracy measured by the imaging component 9 by calculating the extreme value of the relative position error between the measurement group and the reference group of the center of the target 6;

[0088] Relative position error E of the center of target 6 i can be described as:

[0089]

[0090] Among them, the physical coordinates of the center of target 6 in the reference group are (x w0 , y w0 , 0), and the physical coordinates of the center of target 6 in the i-th measurement group are (x wi , y wi , 0).

[0091] In this embodiment, the movement of the working device of the excavation robot is a planar movement in the X and Z directions. Among the repeated positioning data obtained by the two measurement methods, the result measured by the scale 7 can characterize the repeated positioning accuracy of the excavation robot in the Z direction, and the result measured by the imaging component 9 can characterize the repeated positioning accuracy of the excavation robot in the XZ plane. Among them, as Figure 4 shown is a simplified diagram of the DH coordinate system of the excavation robot.

[0092] The above has described in detail the preferred specific embodiments of the present invention. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative work. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field of the present invention through logical analysis, reasoning, or limited experiments based on the concept of the present invention on the basis of the prior art shall fall within the protection scope determined by the claims.

Claims

1. A testing method for the repetitive positioning accuracy testing device of an excavation robot, the testing device comprising an excavation robot, the excavation robot including a turntable (1), an arm (2), a stick (3) and a bucket (4), the turntable (1), the arm (2), the stick (3) and the bucket (4) being connected in series in sequence, characterized in that, The device further includes a target (6), a scale (7), a host computer (8), and a camera component (9); the target (6) is detachably fixed on the bucket (4), the scale (7) is vertically fixed on the horizontal ground, the scale (7) is located in front of the bucket (4), the camera plane of the camera component (9) is parallel to the plane where the target (6) is located, and the camera component (9) is connected to the host computer (8); The test method includes the following steps: S1: Calibrate the parameters of the camera component (9); plan the trajectory during the positioning process of the excavation robot to determine the reference trajectory; S2: The host computer (8) controls the excavation robot to move along the reference trajectory and records the control sequence of the reference trajectory; S3: The camera component (9) shoots the real-time movement process of the bucket (4) and transmits the shooting result to the image processing module to obtain the physical coordinates of the center of the target; S4: Record the center coordinates of the target (6) and the position reading of the scale (7) when the excavation robot moves to the positioning point, and record this set of data as the reference group; S5: After completing the recording of the reference group data, the excavation robot repeats the movement along the reference trajectory of the reference group multiple times, and records the center coordinates of the target (6) and the position reading of the scale (7) when the excavation robot moves to the positioning point. The data after the reference group is recorded as the measurement group; S6: Calculate the repeat positioning accuracy of the excavation robot in the working plane according to the data of the reference group and the measurement group.

2. The testing method of a testing device for the repeated positioning accuracy of an excavation robot according to claim 1, characterized in that, The host computer (8) includes a control module and an image processing module; the control module is used to receive the sensor information of the excavation robot and output a control signal to the excavation robot to control the working device of the excavation robot to move along a predetermined trajectory; the image processing module receives the position information of the target (6) photographed by the camera component (9) and extracts the center coordinates of the target (6) to display the movement trajectory of the bucket (4) in real time.

3. The repeated positioning accuracy testing device for an excavation robot according to claim 1, characterized in that, The material of the target (6) is acrylic board, and the surface of the target (6) is sprayed with red paint.

4. The test method of a test device for the repeated positioning accuracy of an excavation robot according to claim 3, characterized in that A metal rivet is provided at the center position of the target (6), the metal rivet penetrates the target (6), and the metal rivet is adsorbed on the bucket (4) by a strong magnet.

5. The test method of a test device for the repeated positioning accuracy of an excavation robot according to claim 3, characterized in that, A white square paper (5) is provided between the target (6) and the bucket (4), and the area of the white square paper (5) is larger than the area of the target (6).

6. The test method of a test device for the repeated positioning accuracy of an excavation robot according to claim 1, characterized in that, In step S1, the internal parameters, external parameters, and distortion parameters of the camera component (9) are calibrated by the Zhang's calibration method to determine the position mapping relationship between the image pixel coordinate system and the world coordinate system of the plane of the bucket (4) of the excavation robot; The specific calibration process of the parameters of the camera component (9) is as follows: Fix a calibration board with a known size on the plane of the bucket (4), and the host computer (8) controls the bucket (4) of the excavation robot to move to different positions. The camera component (9) with a fixed position shoots 20 groups of checkerboard images at different angles; Detect the feature points of the checkerboard images, determine the pixel coordinate values of the feature points, and calculate the physical coordinate values of the feature points in the world coordinate system according to the known size of the checkerboard calibration board; Solve for the internal parameters, external parameters, and distortion coefficients of the imaging component (9) based on the above measurement data and calibration calculation model: establish the position mapping relationship between the pixel coordinate system and the physical coordinate system by solving the homography matrix H, and then solve for the internal and external parameters and distortion coefficients of the camera. Use the L-M algorithm to optimize the camera calibration parameters; The spatial mapping relationship between the world coordinate system and the pixel coordinate system of the checkerboard is described as: Among them, u and v represent coordinates in the pixel coordinate system, and x w , y w represent coordinates in the world coordinate system; The homography matrix is described as: where s represents the scale factor, f x , f y , γ, u0, v0 represent five internal parameters of the camera, and r1, r2, t represent external parameters of the camera.

7. The testing method of a testing device for the repeated positioning accuracy of an excavation robot according to claim 1, characterized in that In step S1, the trajectory shape is a parabola, and a fifth-degree polynomial is used for trajectory planning to ensure the smoothness of the reference trajectory. The speeds and accelerations of the reference trajectory at the starting point and the positioning point are both set to zero. The trajectory formula is specifically described as: Among them, the pose of the excavation robot at the starting point is The pose of the excavation robot at the positioning point is Point P is the vertex of the parabola, and its coordinates are (h, k).

8. The testing method of a testing device for the repeated positioning accuracy of an excavation robot according to claim 1, characterized in that, The specific process of step S3 is: The imaging component (9) captures the motion process of the working device of the excavation robot in real time. The image processing module of the upper computer (8) extracts the contour of the target (6) image, uses the Hough transform to determine the center position of the target (6), and displays the center trajectory in real time. Determine the bucket (4) trajectory through the center trajectory; convert the pixel coordinates of the center of the target (6) to the physical coordinates in the world coordinate system through the homography matrix.

9. The test method of a test device for the repeated positioning accuracy of an excavation robot according to claim 1, characterized in that, The specific process of step S6 is: Determine the repeat positioning accuracy of the scale (7) measurement by calculating the extreme value of the relative position error between the measurement group and the reference group's scale measurement data; determine the repeat positioning accuracy of the imaging component (9) measurement by calculating the extreme value of the relative position error between the measurement group and the reference group's target (6) center; Relative position error E of the center of the target (6) i Described as: Among them, the physical coordinates of the center of the reference group target (6) are (x w0 , y w0 , 0), and the physical coordinates of the center of the target (6) of the i-th measurement group are (x wi , y wi , 0).

Images