A robot DH parameter and zero point offset calibration method, device and storage medium

Abstract

The application discloses a robot DH parameter and zero point offset calibration method and device and a storage medium. The technical scheme adopts a 3D camera to acquire a calibration board image, calculates position coordinate data points on the calibration board through internal and external parameters of the camera, solves a circle center point by using fitting of nine data points, fits 54 circle center points into joint axes, improves the coincidence degree of a rotary axis and an actual rotary axis by fitting of data points, improves calibration precision, and solves joint robot DH parameters by using geometric relations of space straight lines, which is higher in calibration precision than other methods. The initial angle and zero point offset calibration of the joint are solved by using a common perpendicular line, so that the zero point position is more accurate and precise, and the robot end positioning precision is improved.

Description

Technical Field

[0001] This invention relates to the field of medical devices, specifically to a method, device, and storage medium for calibrating robot DH parameters and zero-point offset. Background Technology

[0002] In the field of robotics, especially medical robotics control, it is particularly important to calibrate the parameters of multi-joint robots and correct zero-point offsets. In the calibration and correction process, the kinematic model parameters of the robot are first established, and the Denavit-Hartenberg (DH) parameter error matrix is ​​solved. Then, with the help of expensive laser tracking instruments, at least 50 data points of the robot are obtained, and the DH parameters of each joint axis are obtained by least squares method. The amount of calculation in this process is huge, the calculation error is large, the cost is high, and the calibration process is extremely complicated.

[0003] Chinese Patent No. 201811597859X discloses a camera vision-based method and device for calibrating the High-Density (DH) parameters of an industrial robot. The robot collects the positions of multiple laser points and their corresponding joint angles at different positions and postures. A computing unit translates the collected points so that the corresponding laser beams intersect at a single point. Using this as a constraint, a nonlinear optimization method is employed to solve for the robot's DH parameter errors, thereby obtaining the DH parameter model. This patent utilizes a camera to acquire the projection point position of the laser beam emitted from the robot's end flange on a plane and combines this with the corresponding robot joint data to complete the DH parameter calibration process.

[0004] Chinese Patent No. 2016106694744 provides a method for calibrating DH parameters and zero-point calibration of an industrial robot based on a laser tracker, including a robot, a robot controller, a computer, and a laser tracker; the computer is electrically connected to the robot controller and the laser tracker respectively; the method includes the following steps: the robot runs to 50 position points; the computer reads the joint angles, and the laser tracker measures the position of the target ball; the computer calculates the corrected DH parameters; a new zero point is set for the robot; and the corrected DH parameters are written to the robot controller. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention proposes a method, device, and storage medium for calibrating robot DH parameters and zero-point offset.

[0006] In a first aspect, the present invention provides a method for calibrating robot DH parameters and zero-point offset, including a 3D camera and a calibration board, comprising the following steps:

[0007] Step 101: Fix the 3D camera;

[0008] Step 102: Attach the calibration board to the end effector of the robot, ensuring that all mark points on the calibration board are within the shooting range of the 3D camera;

[0009] Step 103: Calibrate the internal and external parameters of the 3D camera;

[0010] Step 104: Move each joint of the robot to the modeling origin;

[0011] Step 105: Keep the other joint axes of the robot stationary, move the running axis to -60 degrees, take a picture and save the image;

[0012] Step 106: The single axis moves from the current position every 15 degrees, and the camera takes a picture and saves the image;

[0013] Step 107: Once the position of the running axis reaches 60 degrees, take a picture and save the image to complete the image data acquisition of the running axis;

[0014] Step 108: Determine whether all axis data has been acquired. If not, return to step 104 to continue acquiring images of other joint axes; if yes, proceed to step 109.

[0015] Step 109: Using image data and the intrinsic and extrinsic parameters of the 3D camera, calculate the position data of 54 designated mark points in the camera coordinate system for each image.

[0016] Step 110: Find the spatial straight line of a certain joint axis. Specifically, perform circle fitting on 9 data points of the same mark point collected for the joint axis to obtain the rotation center of the joint axis, which is the center of the circle.

[0017] Step 111: Sequentially obtain the center of the circle for the 9 data points of the other mark points, thus obtaining the remaining 53 center points;

[0018] Step 112: Perform linear fitting on the 54 center points obtained in Steps 110 and 111 to obtain the spatial straight line of the joint axis;

[0019] Step 113: Determine whether the process is complete and all joint axes have been obtained; if not, return to step 110 to continue execution; if yes, execute steps 114 and 115 respectively.

[0020] Step 114: Using spatial geometric relationships, find the angle between two adjacent spatial lines. and the distance of the perpendicular Distance between two points on the common perpendicular of the same straight line and the included angle included angle That is, the link torsion in the DH parameters Distance between the common perpendicular That is, the link length in the DH parameters The distance between the points of two common perpendiculars on a straight line Linkage parameters The angle between two common perpendiculars on a straight line That is, the initial angle of the joint. ;

[0021] Step 115: Calibrate the zero point position of a certain joint axis. Take the position data points A, B and C of the axis at the same mark at -60 degrees, 0 degrees and 60 degrees, and form three straight lines OA, OB and OC with all the center points O respectively. Find the midpoint D of the straight line AC, and then find the angle between the straight line OD and OC, which is the zero point offset angle.

[0022] Step 116: DH parameter calibration completed;

[0023] Step 117: Obtain the remaining joint axis zero-point offset angle to complete the zero-point offset calibration;

[0024] Step 118: Complete the DH parameter and zero offset calibration.

[0025] Furthermore, step 109 further includes: firstly, using OpenCV to solve the transformation matrix from calibration board to camera coordinates. The calibration board has 54 feature points. The following formula 1 is used to solve for the data of the mark points on the calibration board in camera coordinates. Data converted to camera coordinates : , Formula 1.

[0026] Furthermore, step 110 specifically includes the following steps:

[0027] Step 1101: Substitute the 9 data points into the matrix , Find the normal vector A of the plane. The result can be obtained from formula (2). (2);

[0028] Step 1102: Substitute the data of n=9 points into formulas (3), (4), (5), (6), (7), and (8) to obtain the matrix respectively. , :

[0029] (3);

[0030] (4);

[0031] (5);

[0032] (6);

[0033] (7);

[0034] (8);

[0035] Step 1103: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require the full context.] Substitute into formula (9) to obtain the matrix. Formula (10) yields the matrix. ;

[0036] (9);

[0037] (10);

[0038] Step 1104: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require the full context.] , Substitute into formula (11) to find the coordinates of the center of the circle. , , (11).

[0039] Furthermore, step 112 specifically includes the following steps:

[0040] Step 1121: Coordinate the centers of n=54 circles Substitute into formula (12) to find :

[0041] (12);

[0042] Step 1122: Coordinate the centers of n=54 circles Substitute into formula (13) to find :

[0043] (13);

[0044] Step 1123: Coordinate the centers of n=54 circles Substitute into formula (14) to find :

[0045] (14);

[0046] Step 1124: Coordinate the centers of n=54 circles Substitute into formula (15) to find :

[0047] (15);

[0048] Step 1125: Set Z0 as a known constant, and then... , Substitute into formula (16) to find X0:

[0049] ,(16)

[0050] Step 1126: Set Z0 as a known constant, and... , Substituting into formula (17), we can find Y0:

[0051] (17);

[0052] Step 1127: Set P as a known constant, and... Substitute into formula (18) to find :

[0053] (18);

[0054] Step 1128: Set P as a known constant, and... Substitute into formula (19) to find :

[0055] ,(19)

[0056] Step 1129: Further obtain the standard equation formula for a straight line in space (20):

[0057] , (20).

[0058] Furthermore, step 114 further includes the following steps:

[0059] Step 1141: Obtain the link torsion angle Two straight-line direction vectors in three-dimensional space If V2 = {a2, b2, c2}, then the angle between the two straight lines is the torsional angle of the connecting rod. :

[0060] ,(twenty one);

[0061] Step 1142: Obtain the link length:

[0062] Passing point Direction vector of a line The equation of the straight line: ,(twenty two);

[0063] Passing point Direction vector of a line The equation of the straight line: ,(twenty three);

[0064] Obtaining intermediate variables: :

[0065] ;

[0066] ;

[0067] ;

[0068] ;

[0069] ;

[0070] When the angle between two straight lines is 90 degrees, obtain :

[0071] ; ;

[0072] Solving the problem when the included angle between two lines is not 90 degrees. :

[0073] ;

[0074] ;

[0075] The two endpoints of the common perpendicular coordinate: ; ;

[0076] The distance between the common perpendiculars is The distance between the two points is the length of the link. :

[0077] ;

[0078] Step 1143: Obtain link offset:

[0079] Using the method for finding the length of a connecting rod, find two points on the other common perpendicular of the adjacent straight lines. Two points on the same joint axis line The distance is the link offset. : ;

[0080] Step 1144: Obtain the initial angle of the joint. :

[0081] Using the method for finding the length of a connecting rod, find two points on each of the two common perpendiculars of the adjacent straight lines. The coordinates, the angle between the two straight lines P3P4 and P5P6, is the initial angle of the joint angle. :

[0082] Find the direction vector of line P3P4. ;

[0083] ;

[0084] Find the direction vector of line P5P6 ; ;

[0085] Initial angle of joint for .

[0086] Furthermore, step 115 specifically includes the following steps: from the 60-degree joint angle position point -60 degree position point ; Coordinates of the joint's rotation center Point and modeling origin location Find the coordinates of the midpoint D of line segment AB:

[0087] ;

[0088] Obtain the direction vector of line OC :

[0089] ;

[0090] Obtain the direction vector of the line OD :

[0091] ;

[0092] Further obtain the zero-point offset angle : .

[0093] In a second aspect, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the robot DH parameter and zero-point offset calibration method as described in any of the first aspects.

[0094] Thirdly, the present invention provides a robot DH parameter and zero-point offset calibration device, comprising:

[0095] One or more processors;

[0096] Memory; and

[0097] One or more computer programs, wherein the one or more computer programs are stored in the memory and configured to be executed by the one or more processors, wherein the processors, when executing the computer programs, implement the steps of the robot DH parameter and zero-point offset calibration method as described in any of the first aspects.

[0098] This technical solution uses a 3D camera to acquire images of the calibration board. Position coordinate data points on the calibration board are calculated using the camera's intrinsic and extrinsic parameters. The center point is determined by fitting 9 data points, and the joint axis is formed by fitting 54 center points. This data point fitting improves the fit between the rotation axis and the actual rotation axis, thus enhancing calibration accuracy. The link torsion is obtained by calculating the angle between two spatial lines, and the link length is calculated by the distance between the common perpendiculars of these lines. The link offset is calculated by the distance between adjacent common perpendiculars, and the initial joint angle can be determined by the angle between two adjacent common perpendiculars. The zero-point offset angle is calculated by finding the midpoint of a line connecting two points equal to the zero point. Using the geometric relationship of spatial lines to solve for the DH parameters of the joint robot provides higher calibration accuracy than other methods. Solving for the initial joint angle and zero-point offset using common perpendiculars results in a more accurate and precise zero-point position. This approach is cost-effective, simple to calibrate, and computationally efficient, contributing to improved robot end-effector positioning accuracy. Attached Figure Description

[0099] Figure 1 Schematic diagram of the experimental setup for calibrating robot DH parameters and zero-point offset.

[0100] Figure 2 : Schematic diagram of DH parameters for articulated robot.

[0101] Figure 3 Flowchart of robot DH parameters and zero-point offset calibration method.

[0102] Figure 4 : Calibration template diagram.

[0103] Figure 5 Schematic diagram of solving the DH parameters of the robot.

[0104] Figure 6 Robot zero-point offset calibration diagram.

[0105] Figure 7 Schematic diagram of robot DH parameters and zero-point offset calibration equipment. Detailed Implementation

[0106] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0107] refer to Figure 1 Schematic diagram of the experimental setup for robot DH parameters and zero-point offset calibration method. Figure 2 The schematic diagram of the DH parameters of the articulated robot shows that the DH parameter modeling of the articulated robot of this invention has four parameters, namely link length, link torsion, link offset and joint angle.

[0108] refer to Figure 3 The flowchart of the robot DH parameter and zero-point offset calibration method of the present invention includes the following steps:

[0109] Step 101: Fix the 3D camera;

[0110] Step 102: Attach the calibration board to the end effector of the robot, ensuring that all mark points on the calibration board are within the shooting range of the 3D camera;

[0111] Step 103: Calibrate the internal and external parameters of the 3D camera;

[0112] Step 104: Move each joint of the robot to the modeling origin;

[0113] Step 105: Keep the other joint axes of the robot stationary, move the running axis to -60 degrees, take a picture and save the image;

[0114] Step 106: The single axis moves from the current position every 15 degrees, and the camera takes a picture and saves the image;

[0115] Step 107: Once the position of the running axis reaches 60 degrees, take a picture and save the image to complete the image data acquisition of the running axis;

[0116] Step 108: Determine whether all axis data has been acquired. If not, return to step 104 to continue acquiring images of other joint axes; if yes, proceed to step 109.

[0117] Step 109: Using image data and the intrinsic and extrinsic parameters of the 3D camera, calculate the position data of 54 designated mark points in the camera coordinate system for each image.

[0118] Step 110: Find the spatial straight line of a certain joint axis. Specifically, perform circle fitting on 9 data points of the same mark point collected for the joint axis to obtain the rotation center of the joint axis, which is the center of the circle.

[0119] Step 111: Sequentially obtain the center of the circle for the 9 data points of the other mark points, thus obtaining the remaining 53 center points;

[0120] Step 112: Perform linear fitting on the 54 center points obtained in Steps 110 and 111 to obtain the spatial straight line of the joint axis;

[0121] Step 113: Determine whether the process is complete and all joint axes have been obtained; if not, return to step 110 to continue execution; if yes, execute steps 114 and 115 respectively.

[0122] Step 114: Using spatial geometric relationships, find the angle between two adjacent spatial lines. and the distance of the perpendicular Distance between two points on the common perpendicular of the same straight line and the included angle included angle That is, the link torsion in the DH parameters Distance between the common perpendicular That is, the link length in the DH parameters The distance between the points of two common perpendiculars on a straight line Linkage parameters The angle between two common perpendiculars on a straight line That is, the initial angle of the joint. ;

[0123] Step 115: Calibrate the zero point position of a certain joint axis. Take the position data points A, B and C of the axis at the same mark at -60 degrees, 0 degrees and 60 degrees, and form three straight lines OA, OB and OC with all the center points O respectively. Find the midpoint D of the straight line AC, and then find the angle between the straight line OD and OC, which is the zero point offset angle.

[0124] Step 116: DH parameter calibration completed;

[0125] Step 117: Obtain the remaining joint axis zero-point offset angle to complete the zero-point offset calibration;

[0126] Step 118: Complete the DH parameter and zero offset calibration.

[0127] refer to Figure 4 The calibration template diagram, step 109 specifically includes the following steps: solving for the coordinate data of the mark points on the calibration board in the camera coordinate system, firstly solving for the transformation matrix from the calibration board to the camera coordinate system. The calibration board has 54 feature points. This scheme uses the method provided in OpenCV to solve the transformation matrix. The intrinsic and extrinsic parameters of the 3D camera are set by the camera. The transformation matrix Rt is solved using the following formula: Formula 1 is used to calculate the data of the mark points on the calibration plate in camera coordinates. The coordinate data on the calibration plate... Data converted to camera coordinates :

[0128] , Formula 1;

[0129] Furthermore, step 110 specifically includes the following steps:

[0130] Step 1101: Substitute the 9 data points into the matrix , Find the normal vector A of the plane. It can be obtained from formula (2);

[0131] ;

[0132] Step 1102: Substitute the data of n=9 points into formulas (3), (4), (5), (6), (7), and (8) to obtain the matrix respectively. , :

[0133] ;

[0134] ;

[0135] ;

[0136] ;

[0137] ;

[0138] ;

[0139] Step 1103: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require the full context.] Substitute into formula (9) to obtain the matrix. Formula (10) yields the matrix. :

[0140] ; ;

[0141] Step 1104: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require the full context.] , Substitute into formula (11) to find the coordinates of the center of the circle. :

[0142] ,(11)

[0143] Furthermore, step 112 specifically includes the following steps:

[0144] Step 1121: Assign coordinates to the centers of n=54 circles { } Substitute into formula (12) to find

[0145] ;

[0146] Step 1122: Coordinate the centers of n=54 circles { } Substitute into formula (13) to find :

[0147] ;

[0148] Step 1123: Coordinate the centers of n=54 circles { } Substitute into formula (14) to find :

[0149] ;

[0150] Step 1124: Coordinate the centers of n=54 circles { } Substitute into formula (15) to find :

[0151] ;

[0152] Step 1125: Set Z0 as a known constant, and then... , Substitute into formula (16) to find X0:

[0153] ;

[0154] Step 1126: Set Z0 as a known constant, and... , Substitute into formula (17) to find Y0

[0155] ;

[0156] Step 1127: Set P as a known constant, and... Substitute into formula (18) to find

[0157] ;

[0158] Step 1128: Set P as a known constant, and... Substitute into formula (19) to find

[0159] ;

[0160] Step 1129: Further obtain the standard equation formula for a straight line in space (20):

[0161] ;

[0162] Further reference Figure 5 A schematic diagram of solving the robot DH parameters, wherein step 114 further includes the following steps:

[0163] Step 1141: Obtain the link torsion angle :

[0164] Direction vectors of two straight lines in three-dimensional space V2 = {a2, b2, c2};

[0165] The angle between the two straight lines is the torsional angle of the connecting rod. : ,(twenty one);

[0166] Step 1142: Obtain the link length:

[0167] Passing point Direction vector of a line The equation of the straight line:

[0168] ;

[0169] Passing point Direction vector of a line The equation of the straight line:

[0170] ;

[0171] Get intermediate variables :

[0172] ;

[0173] ;

[0174] ;

[0175] ;

[0176] ;

[0177] When the angle between two straight lines is 90 degrees, obtain :

[0178] ;

[0179] ;

[0180] Solving the problem when the included angle between two lines is not 90 degrees. :

[0181] ;

[0182] ;

[0183] The two endpoints of the common perpendicular coordinate:

[0184] ;

[0185] ;

[0186] The distance between the common perpendiculars is The distance between the two points is the length of the link. :

[0187] ;

[0188] Step 1143: Obtain link offset:

[0189] Using the method for finding the length of a connecting rod, find two points on the other common perpendicular of the adjacent straight lines. Two points on the same joint axis line The distance is the link offset. :

[0190] ;

[0191] Step 1144: Obtain the initial angle of the joint. :

[0192] Using the method for finding the length of a connecting rod, find two points on each of the two common perpendiculars of the adjacent straight lines. The coordinates, the angle between the two straight lines P3P4 and P5P6, is the initial angle of the joint angle. :

[0193] Find the direction vector of line P3P4.

[0194] ;

[0195] Find the direction vector of line P5P6

[0196] ;

[0197] Initial angle of joint for ;

[0198] Further reference Figure 6 Robot zero-point offset calibration diagram, step 115 specifically includes the following steps:

[0199] From the 60-degree joint angle point -60 degree position point Coordinates of the rotation center of the joint Point and modeling origin location Find the coordinates of the midpoint D of line segment AB:

[0200] ;

[0201] Find the direction vector of line OC. :

[0202] ;

[0203] Find the direction vector of line OD. :

[0204] ;

[0205] Further obtain the zero-point offset angle : .

[0206] For the foregoing method embodiments, in order to simplify the description, they are all described as a series of actions. However, those skilled in the art should know that this application is not limited to the described order of actions, because according to this application, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0207] The steps in the method of this application embodiment can be adjusted, merged, or deleted in order according to actual needs, and the technical features described in the embodiment can be replaced or combined with equivalents.

[0208] It should be noted that, for the device-type embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and relevant parts can be referred to in the description of the method embodiments.

[0209] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, which may include: read-only memory (ROM), random access memory (RAM), disk or optical disk, etc.

[0210] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for calibrating robot DH parameters and zero-point offset, comprising a 3D camera and a calibration board, characterized in that, Includes the following steps: Step 101: Fix the 3D camera; Step 102: Attach the calibration board to the end effector of the robot, ensuring that all mark points on the calibration board are within the shooting range of the 3D camera; Step 103: Calibrate the internal and external parameters of the 3D camera; Step 104: Move each joint of the robot to the modeling origin; Step 105: Keep the other joint axes of the robot stationary, move the running axis to -60 degrees, take a picture and save the image; Step 106: The single axis moves from the current position every 15 degrees, and the camera takes a picture and saves the image; Step 107: Once the position of the running axis reaches 60 degrees, take a picture and save the image to complete the image data acquisition of the running axis; Step 108: Determine whether all axis data has been acquired. If not, return to step 104 to continue acquiring images of other joint axes; if yes, proceed to step 109. Step 109: Using image data and the intrinsic and extrinsic parameters of the 3D camera, calculate the position data of 54 designated mark points in the camera coordinate system for each image. Step 110: Find the spatial straight line of a certain joint axis. Specifically, perform circle fitting on 9 data points of the same mark point collected for the joint axis to obtain the rotation center of the joint axis, which is the center of the circle. Step 111: Sequentially obtain the center of the circle for the 9 data points of the other mark points, thus obtaining the remaining 53 center points; Step 112: Perform linear fitting on the 54 center points obtained in Steps 110 and 111 to obtain the spatial straight line of the joint axis; Step 113: Determine whether the process is complete and all joint axes have been obtained; if not, return to step 110 to continue execution; if yes, execute steps 114 and 115 respectively. Step 114: Using spatial geometric relationships, find the angle between two adjacent spatial lines. and the distance of the perpendicular Distance between two points on the common perpendicular of the same straight line and the included angle included angle That is, the link torsion in the DH parameters Distance between the common perpendicular That is, the link length in the DH parameters The distance between the points of two common perpendiculars on a straight line Linkage parameters The angle between two common perpendiculars on a straight line That is, the initial angle of the joint. ; Step 115: Calibrate the zero point position of a certain joint axis. Take the position data points A, B and C of the axis at the same mark at -60 degrees, 0 degrees and 60 degrees, and form three straight lines OA, OB and OC with all the center points O respectively. Find the midpoint D of the straight line AC, and then find the angle between the straight line OD and OC, which is the zero point offset angle. Step 116: DH parameter calibration completed; Step 117: Obtain the remaining joint axis zero-point offset angle to complete the zero-point offset calibration; Step 118: Complete the DH parameter and zero offset calibration.

2. The robot DH parameter and zero-point offset calibration method as described in claim 1, characterized in that, Step 109 further includes: firstly, using OpenCV to solve the transformation matrix from calibration board to camera coordinates. The calibration board has 54 feature points. The following formula 1 is used to solve for the data of the mark points on the calibration board in camera coordinates. Data converted to camera coordinates : , Formula 1.

3. The robot DH parameter and zero-point offset calibration method as described in claim 1, characterized in that, Step 110 specifically includes the following steps: Step 1101: Substitute the 9 data points into the matrix , Find the normal vector A of the plane. The result can be obtained from formula (2). (2); Step 1102: Substitute the data of n=9 points into formulas (3), (4), (5), (6), (7), and (8) to obtain the matrix respectively. , : ，（3）； ，（4）； （5）； ，（6）； ，（7）； ，（8）； Step 1103: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would Substitute into formula (9) to obtain the matrix. Formula (10) yields the matrix. ; ，（9）； ，（10）； Step 1104: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require the full context.] , Substitute into formula (11) to find the coordinates of the center of the circle. , , (11).

4. The robot DH parameter and zero-point offset calibration method as described in claim 1, characterized in that, Step 112 specifically includes the following steps: Step 1121: Coordinate the centers of n=54 circles Substitute into formula (12) to find : ，（12）； Step 1122: Coordinate the centers of n=54 circles Substitute into formula (13) to find : ，（13）； Step 1123: Coordinate the centers of n=54 circles Substitute into formula (14) to find : ，（14）； Step 1124: Coordinate the centers of n=54 circles Substitute into formula (15) to find : ，（15）； Step 1125: Set Z0 as a known constant, and then... , Substitute into formula (16) to find X0: ，（16）； Step 1126: Set Z0 as a known constant, and... , Substituting into formula (17), we can find Y0: ，（17）； Step 1127: Set P to a known constant, and... Substitute into formula (18) to find : ，（18）； Step 1128: Set P as a known constant, and... Substitute into formula (19) to find : ，（19）； Step 1129: Further obtain the standard equation formula for a straight line in space (20): ，（20）。 5. The robot DH parameter and zero-point offset calibration method as described in claim 1, characterized in that, Step 114 further includes the following steps: Step 1141: Obtain the link torsion angle Two straight-line direction vectors in three-dimensional space If V2 = {a2, b2, c2}, then the angle between the two straight lines is the torsional angle of the connecting rod. : ，（21）； Step 1142: Obtain the link length: Passing point Direction vector of a line The equation of the straight line: ,(twenty two); Passing point Direction vector of a line The equation of the straight line: ,(twenty three); Obtaining intermediate variables: : ； ； ； ； ； When the angle between two straight lines is 90 degrees, obtain : ； ； Solving the problem when the included angle between two lines is not 90 degrees. : ； ； The two endpoints of the common perpendicular coordinate: ; ; The distance between the common perpendiculars is The distance between the two points is the length of the link. : ； Step 1143: Obtain link offset: Using the method for finding the length of a connecting rod, find two points on the other common perpendicular of the adjacent straight lines. Two points on the same joint axis line The distance is the link offset. : ; Step 1144: Obtain the initial angle of the joint. : Using the method for finding the length of a connecting rod, find two points on each of the two common perpendiculars of the adjacent straight lines. The coordinates, the angle between the two straight lines P3P4 and P5P6, is the initial angle of the joint angle. : Find the direction vector of line P3P4. ; ； Find the direction vector of line P5P6 ; ; Initial angle of joint for .

6. The robot DH parameter and zero-point offset calibration method as described in claim 1, characterized in that, Step 115 specifically includes the following steps: from the 60-degree joint angle point... -60 degree position point ; Coordinates of the joint's rotation center Point and modeling origin location Find the coordinates of the midpoint D of line segment AB: ； Obtain the direction vector of line OC : ； Obtain the direction vector of the line OD : ； Further obtain the zero-point offset angle : .

7. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the robot DH parameter and zero-point offset calibration method as described in any one of claims 1 to 6.

8. A device for calibrating robot DH parameters and zero-point offset, comprising: One or more processors; Memory; as well as One or more computer programs, wherein the one or more computer programs are stored in the memory and configured to be executed by the one or more processors, characterized in that, when the processor executes the computer program, it implements the steps of the robot DH parameter and zero-point offset calibration method as described in any one of claims 1 to 6.

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