A method for robot end tool coordinate system calibration

Abstract

The application is a kind of method for robot end tool coordinate system calibration, characterized in that, step one, installation of calibration device: industrial robot, calibration plate based on laser transmission sensor, calibration tool and host computer control system are composed; industrial robot is connected with host computer control system and calibration plate based on laser transmission sensor respectively; calibration plate based on laser transmission sensor is connected; calibration tool is installed at the end of industrial robot flange; the calibration plate composed of laser transmission sensor is used as the transfer station reference, manual participation is extremely low, the running of calibration action and the fitting of tool coordinate system key size are completely completed by host computer automatically, the whole process is fast and convenient.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for robot end tool coordinate system calibration, in particular to a robot machining system using offline programming for machining trajectory planning. BACKGROUND

[0002] The end tool of the cutting robot is mainly a cylindrical tool such as a milling cutter, a drill bit, and a tap. When the machining program is designed through offline programming, the pose conversion matrix of the tool tip point relative to the center of the robot flange is needed. The traditional tool coordinate system calibration needs to use a laser tracker, a tool setting instrument, and a specially customized calibration rod, which is expensive. Moreover, it needs specially trained operators and complete permission space point fitting algorithm software (such as Spatial Analyzer) to realize calibration, which is time-consuming and laborious. For the robot machining system that needs to frequently disassemble the actuator and the tool, the cost of time required for calibration will be further increased. Therefore, a calibration device with faster calibration speed and higher pertinence for robot cutting machining systems is developed to reduce the time required for calibration. The integrated calibration device is designed based on a laser transmission sensor, and the calibration tip point installed on the robot communicates with the upper computer system. Through the instructions planned in advance, the calibration action and the pose capture are realized, and the tool coordinate system is quickly fitted and calculated. After integration with the offline programming system, the process file required for machining can be quickly generated. The calibration steps of the tool coordinate system and the planning steps of the offline programming are integrated, and through the intelligent and man-machine interface friendly process management system, the running state of the robot machining system that needs to frequently replace the actuator and the tool can be controlled in real time. SUMMARY

[0003] The purpose of the present application is to provide a robot end tool coordinate system calibration system to solve the problem of tool tip pose calibration when a cutting machining robot runs in an offline programming mode.

[0004] A method for robot end tool coordinate system calibration, characterized in that,

[0005] Step one, install the calibration device: an industrial robot, a calibration plate based on a laser transmission sensor, a calibration tool, and an upper computer control system are composed; the industrial robot is connected with the upper computer control system and the calibration plate based on the laser transmission sensor, and the calibration plate based on the laser transmission sensor is connected; the calibration tool is installed at the end of the industrial robot flange;

[0006] Step two, complete the entire calibration process through the upper computer program controlled by the Qt interface development;

[0007] Step three, manual teaching: align the calibration tool tip mounted on the end flange of the industrial robot with the intersection of the two laser beams emitted by the laser beam-based calibration board, so that the calibration tool tip can simultaneously block the two laser beams, and record the pose of the robot flange in the base coordinate system;

[0008] Step four, calibration of the laser beam coordinate system: send motion instructions to the robot through the upper computer control software to perform a predetermined calibration action, and the calibration tool tip on the end flange of the robot, according to the preset motion program of the upper computer, obtains the corresponding flange pose of the robot in the base coordinate system when the tip blocks or connects the light beam during the execution of the calibration action, and the relative pose of the laser beam coordinate system in the robot base coordinate system is obtained through algorithm fitting, so as to convert the working space to the laser beam coordinate system;

[0009] Step five, calibration of the tool coordinate system: replace the calibration tool on the end flange of the robot with the actual tool, align the tip of the tool with the intersection of the laser beams, and execute the preset action of the upper computer to obtain the corresponding pose data of the actual tool when connecting or disconnecting the light beam in the beam coordinate system. Through fitting, the tool coordinate system of the actual tool is obtained; the calibration is completed.

[0010] The step three manual teaching is specifically: through the manual quick teaching function of the robot, adjust the mode to "flange surface parallel to the ground", so that the tip is quickly adjusted to a vertically downward state; through the teach pendant, adjust the position of the flange in the robot base coordinate system mode, so that the tip can simultaneously block the laser beams emitted by the two sensors; record the coordinates of the center of the robot flange as [x0 y0 z0] at this time through the upper computer operation software; since the quick adjustment mode is used to make the flange surface parallel to the ground, the attitude is [180° 0° 180°].

[0011] The step four of calibrating the laser beam coordinate system has the following specific process: based on the high repeat positioning accuracy of the robot, the laser beam coordinate system is constructed based on the laser beams of the calibration board. The operator sends a robot motion instruction through the upper computer software, and the robot carrying the high-precision tip moves according to the following trajectory:

[0012] (a) the robot is lifted to 50mm above the beam plane;

[0013] (b) through the upper computer, the robot pose real-time recording function is turned on, and at the same time, the tip is translated by a proper distance R in a plane parallel to the XY plane of the base coordinate system, to ensure that the tip will not cause the sensor to connect or disconnect the light when it is lowered, and the tip is lowered by 100mm along the Z axis of the robot base coordinate system, so that the connection between the cylindrical surface and the conical surface of the tip is located 50mm below the laser beam plane;

[0014] (c) through the host computer control start calibration motion program: robot flange to maintain the pose [180 ° 0 ° 180 °], with [x0 y0 z0-50] as the center, the distance R as the radius according to the whole circle track movement, in which the x, y two groups of laser sensor occurs four times, four times, through the host computer software and robot control system, calibration plate sensor interaction, record the four times of light break robot flange position Dx1, Dy1, Dx2, Dy2, four times of light connection robot flange position recorded as Jx1, Jy1, Jx2, Jy2; the record obtained 8 position for connecting four groups of line segment: Dx1-Dx2, Jx1-Jx2, Dy1-Dy2, Jy1-Jy2, wherein Dx1-Dx2, Jx1-Jx2 intersection point recorded as X1, Dy1-Dy2, Jy1-Jy2 intersection point recorded as Y1;

[0015] (d) respectively with [x0 y0 z0-60], [x0 y0 z0-70], [x0 y0 z0-80], [x0 y0 z0-90] as the center, the distance R as the radius according to the whole circle track movement, repeat the light break and robot pose recording step in the third step, get the following robot base coordinate system in space point position: X2, Y2, X3, Y3, X4, Y4, X5, Y5;

[0016] (e) fitting, X1, X2, X3, X4, X5 fitting to get straight line vector Y1, Y2, Y3, Y4, Y5 fitting to get straight line vector And the following processing: to the vector And Equal proportion transformation, so that the third element becomes 1, that is, the transformation is:

[0017]

[0018] (f) calculate the following vector:

[0019]

[0020] To Unitization processing:

[0021]

[0022] That is the calibration rod axis (flange coordinate system Z axis) in the beam coordinate system of the vector;

[0023] (j) solve And the angle between the two vectors [0 0 1] alpha,

[0024]

[0025] The cross product of [0 0 1] and two vectors is:

[0026]

[0027] The pose transformation matrix between the beam coordinate system and the robot tip coordinate system is:

[0028]

[0029] In the flange coordinate system of the robot, the tip is at a position 150mm along the Z-axis of the flange coordinate system:

[0030] P = [0 150]

[0031] The pose matrix of the flange center point in the beam coordinate system is:

[0032]

[0033] The pose matrix of the flange center point in the robot base coordinate system is:

[0034]

[0035] The transformation relationship between the beam coordinate system and the flange coordinate system is:

[0036]

[0037] At this point, the beam coordinate system calibration is complete.

[0038] The specific content of step five is:

[0039] (a) Disassemble the calibration tip fixed to the flange, replace it with the actual actuator and the actual tool, manually align the tool tip and the intersection of the two laser beams, and make the axis direction of the tip roughly perpendicular to the laser beam plane, record the robot flange center coordinates flangepoint2 = [x2 y2 z2] and Euler angles [A2 B2 C2] at this time;

[0040] (b) Convert the Euler angles [A2 B2 C2] to the corresponding pose matrix R according to the order recognized by the robot control system, and form the following pose matrix:

[0041]

[0042] (c) Calculate the following matrix:

[0043]

[0044] Where matrix T1 represents the orientation of the flange coordinate system in the beam coordinate system, and the first three numbers in the fourth column form the coordinates of the point resultpoint;

[0045] (d) Keeping the robot flange attitude unchanged, the robot carrying the actuator and equivalent cusp descends another 5 steps. The fitted vector is obtained by using the obtained point cloud data and the similarity method of the calibrated beam coordinate system.

[0046] (e) In the beam coordinate system, the point coordinate resultpoint is the flange center coordinate, and the origin [0 0 0] is the tool point coordinate. The relative position of the two is the position of the tool coordinate system origin relative to the flange center. The tool coordinate system origin information calibration is completed.

[0047] (f) Find The angle between [0 0 1] is used to obtain the attitude transformation matrix T2 between the beam coordinate system and the robot cusp coordinate system using the Rodrigues transformation (the process is similar to the calculation of T and will not be repeated). This gives the pose matrix of the cusp coordinate system in the beam coordinate system at this point:

[0048]

[0049] The vector formed by the third column of T2 is the direction of the tool axis in the beam coordinate system;

[0050] (j) The attitude transformation matrix between the tool coordinate system and the flange coordinate system is:

[0051]

[0052] The pose transformation matrix is:

[0053]

[0054] The tool coordinate system calibration is now complete.

[0055] The calibration tool consists of a flange adapter and calibration tips, and is made of 45 steel. The size and distribution of the mounting holes on the flange adapter are determined according to the relevant dimensions of the robot flange to be calibrated.

[0056] Step one described above can be applied to most industrial robots, collaborative robots, and robotic arms that have high-speed I / O ports and can realize signal transmission and communication functions.

[0057] The laser transmission sensor on the calibration board and the high-speed IO port of the robot carry out signal real-time interaction, so that the communication between the robot and the sensor signal is realized, and the linkage between the robot pose and the light shielding point position is realized; the laser beam diameter of the laser transmission sensor is 0.5mm, the installation position accuracy is guaranteed by machining, the response time of the robot IO port is 4ms, and through experiment verification, when the programmed speed of the robot is not more than 20% of the maximum running speed, the light shielding and light receiving signals at each point can be accurately and timely received and analyzed, and the accurate matching between the robot pose and the signal is ensured.

[0058] The present application has the following advantages:

[0059] The present application communicates with the robot through the host computer and sends a motion instruction, controls the calibration sharp point carried by the robot flange to move according to the predetermined trajectory and shield the laser transmission sensor signal, automatically records the robot pose when the light is shielded, and then analyzes the relationship between the calibration board and the robot base coordinate system; after the robot replaces the actual actuator, the host computer sends a motion instruction to shield the laser signal and records the corresponding pose of the robot, and after analysis and calculation, the pose of the actuator tool sharp point relative to the flange can be determined, so that the accurate size of the tool coordinate system is calibrated, and the host computer software is integrated into the offline programming software, which can quickly assist in processing trajectory posture planning, has strong practicability and good popularization.

[0060] The present application uses the calibration board composed of the laser transmission sensor as the stationing reference, the manual participation is extremely low, the running of the calibration action and the fitting of the key size of the tool coordinate system are completely relied on the host computer to complete automatically, the whole process is fast and convenient, and the key size from the robot flange end to the tool sharp point can be identified without high-precision calibration equipment such as tool setting instrument and laser tracker; the tool coordinate system size calibration result is output in the form of a process file, and through opening a port in the offline programming software of the robot machining system, the process file required for robot machining operation can be directly generated according to the machining points of the product tooling, which is convenient and fast. BRIEF DESCRIPTION OF DRAWINGS

[0061] Figure 1 It is the hardware structure diagram corresponding to the robot end tool coordinate system calibration method of the present application.

[0062] The figure is marked as: 1-industrial robot, 2-calibration tip, 3-calibration board, 4-host computer system. Among them, the host computer system and the robot are connected through the network cable, and the data and instructions are transmitted through the TCP / IP protocol. The host computer software is developed based on the SDK development package of the robot itself. It can send motion instructions to the robot. The robot carries the tip between the laser beams emitted by the sensor of the calibration board. The sensor signal line is connected to the IO port of the robot. The pose of the robot is recorded at the moment when the sensor is disconnected. Through socket, it is transmitted back to the host computer and fitted to calculate the tool coordinate system information installed on the flange end.

[0063] Figure 2 The tip structure diagram for calibrating the light beam coordinate system.

[0064] (a) Calibration tip perspective view;

[0065] (b) Calibration tip structure front view;

[0066] (c) is the right view of (b);

[0067] When calibrating the tip, the coaxial accuracy of the tip and the flange axis of the robot and the distance accuracy from the flange mounting surface to the tip are ensured by machining. The hole distribution size of the tip mounting surface is designed based on the threaded mounting hole of the robot flange.

[0068] Figure 3 The calibration board structure diagram based on two groups of laser shooting type sensors.

[0069] (a) Calibration board perspective view;

[0070] (b) Calibration board structure diagram;

[0071] (c) is the top view of the calibration board; This integrated calibration board with two groups of sensors is produced by CAPTRON company. The laser emitting end, receiving end and signal line are all filled in the slot in the board. The structure is simple. The laser beam spot diameter is 0.5mm, and the laser beam is 650nm red. The two laser beams on the calibration board are marked as x, y.

[0072] The calibration board does not deliberately make the two beams absolutely perpendicular to each other in structure, and the two beams do not deliberately intersect at a point in space. Because the intersection of the beams will cause mutual interference of the signals of the two pairs of sensors (similar phenomenon will occur when multiple groups of laser ranging sensors intersect), but the direction of the beam itself is not used as the coordinate axis during calibration. The key point is the vector obtained by the cross product of the directions of the two laser beams. The following operation steps can know that the structure does not affect the calibration result.

[0073] Figure 4The robot tool coordinate system calibration system is mainly composed of an industrial robot, a calibration board, an upper computer control system and a calibration sharp point.

[0074] Figure 5 The calibration sharp point is lifted to 50mm above the light beam plane.

[0075] Figure 6 The calibration sharp point is lifted to 50mm below the light beam plane.

[0076] Figure 7 The calibration sharp point is lifted to 50mm below the light beam plane.

[0077] Figure 8 The calibration sharp point is lifted to 50mm below the light beam plane. Specific embodiments:

[0078] The robot tool coordinate system calibration system of the present application mainly comprises an industrial robot, a calibration board, an upper computer control system and a calibration sharp point.

[0079] As shown in the accompanying drawings, the robot tool coordinate system calibration system of the present application mainly comprises an industrial robot, a calibration board, an upper computer control system and a calibration sharp point. Figure 1 The calibration sharp point is lifted to 50mm above the light beam plane.

[0080] The calibration sharp point is lifted to 50mm below the light beam plane.

[0081] The calibration board 2 is fixed in the workspace of the industrial robot by a bolted plate, and the power lines of the two groups of laser transmission sensors on the calibration board are connected to a 24V DC power supply, and the signal lines are connected to the high-speed IO port of the robot 1. The robot 1 is connected to the host computer 4 through a network cable. The fixed-size calibration sharp point is fixed on the flange end of the robot 1 by a screw connection, and the sharp point is located 150 mm away from the flange end surface on the 6th axis of the robot. The connection between the sharp point and the flange has a pin hole for positioning, which ensures the assembly size accuracy of the sharp point.

[0082] The calibration process is divided into the following three parts:

[0083] (1) Manual quick teaching:

[0084] The calibration sharp point is fixed on the flange end of the robot by a bolt, and the quick teaching function of the robot is adjusted to "flange surface parallel to the ground", so that the sharp point is quickly adjusted to a vertical downward state. Through the teach pendant, the position of the flange is adjusted in the robot base coordinate system mode, so that the sharp point can block the laser beams emitted by the two sensors at the same time, as shown in Figure 5 , the coordinates of the center of the robot flange at this time are recorded by the host computer operation software as [x0 y0 z0]. Since the quick adjustment mode is set to "flange surface parallel to the ground", the attitude at this time is [180° 0° 180°].

[0085] (2) Calibration beam coordinate system

[0086] Based on the high repeatability of the robot, a beam coordinate system is constructed for the laser beam of the calibration board. The operator sends a robot motion command through the host computer software, and the robot carrying the high-precision sharp point moves along the following trajectory:

[0087] 1. The robot is lifted to 50 mm above the beam plane, as shown in Figure 6 ;

[0088] 2. The host computer is used to start the real-time recording function of the robot pose, and at the same time, the sharp point is translated by a proper distance R in a plane parallel to the XY plane of the base coordinate system, to ensure that the sharp point will not cause the sensor to disconnect when it is lowered. Along the Z axis of the robot base coordinate system, it is lowered by 100 mm, so that the connection between the cylindrical surface and the conical surface of the sharp point is located 50 mm below the laser beam plane, as shown in Figure 7 ;

[0089] 3. Start the motion program of calibration by the host computer: the robot flange keeps the posture of [180° 0° 180°], and moves along the whole circle trajectory with [x0 y0 z0-50] as the center and R as the radius, in which the x and y groups of the pair of laser sensors occur four times of light break and four times of light connection, through the interaction of the host computer software, the robot control system and the calibration plate sensors, the robot flange positions of the four times of light break Dx1, Dy1, Dx2, Dy2 and the four times of light connection Jx1, Jy1, Jx2, Jy2 are recorded; the eight positions obtained by recording are connected to obtain four groups of line segments: Dx1-Dx2, Jx1-Jx2, Dy1-Dy2, Jy1-Jy2, wherein the intersection of Dx1-Dx2 and Jx1-Jx2 is recorded as X1, and the intersection of Dy1-Dy2 and Jy1-Jy2 is recorded as Y1, as shown in Figure 8

[0090] 4. Take [x0 y0 z0-60], [x0 y0 z0-70], [x0 y0 z0-80] and [x0 y0 z0-90] as the center respectively, and move along the whole circle trajectory with R as the radius, repeat the light break and light connection and the robot posture recording steps in the step 3, to obtain the following space points in the robot base coordinate system: X2, Y2, X3, Y3, X4, Y4 and X5, Y5.

[0091] 5. Perform fitting, and the straight line vector is obtained by fitting X1, X2, X3, X4 and X5, and the straight line vector is obtained by fitting Y1, Y2, Y3, Y4 and Y5. Perform equal proportion transformation on the vectors and

[0092] , so that the third element becomes 1, that is, the transformation is as follows:

[0093] 6. Calculate the following vectors:

[0094]

[0095] Perform unitization processing on :

[0096]

[0097] That is, the vector of the calibration rod axis (flange coordinate system Z axis) in the light beam coordinate system.

[0098] 7. Solve the angle α between the vectors and [0 0 1].

[0099]

[0100] The cross product of [0 0 1] and two vectors is:

[0101]

[0102] The pose transformation matrix between the beam coordinate system and the robot tip coordinate system is:

[0103]

[0104] In the flange coordinate system of the robot, the tip is at a position 150 mm along the Z-axis of the flange coordinate system:

[0105] P =

[00150]

[0106] The pose matrix of the flange center point in the beam coordinate system is:

[0107]

[0108] The pose matrix of the flange center point in the robot base coordinate system is:

[0109]

[0110] The transformation relationship between the beam coordinate system and the flange coordinate system is:

[0111]

[0112] At this point, the beam coordinate system calibration is complete.

[0113] (2) Calibrate the actual tool coordinate system

[0114] 1. Disassemble the calibration tip fixed to the flange, replace it with the actual actuator and the actual tool, manually align the tool tip and the intersection of the two laser beams, and make the axis direction of the tip roughly perpendicular to the laser beam plane. Record the robot flange center coordinates flangepoint2 = [x2 y2 z2] and Euler angles [A2 B2 C2] at this time;

[0115] 2. Convert the Euler angles [A2 B2 C2] to the corresponding pose matrix R according to the order recognized by the robot control system, and form the following pose matrix:

[0116]

[0117] 3. Calculate the following matrix:

[0118]

[0119] Where matrix T1 represents the orientation of the flange coordinate system in the beam coordinate system, and the first three numbers in the fourth column form the coordinates of the point resultpoint;

[0120] 4. Keeping the robot flange attitude unchanged, the robot, carrying the actuator and equivalent cusp, descends again in five steps. The fitted vector is obtained using the point cloud data and the similarity method of the calibrated beam coordinate system.

[0121] 5. In the beam coordinate system, the point coordinate resultpoint is the flange center coordinate, and the origin [0 0 0] is the tool point coordinate. The relative position of the two is the position of the tool coordinate system origin relative to the flange center. The origin information of the tool coordinate system is calibrated.

[0122] 6. Seek The angle between [0 0 1] is used to obtain the attitude transformation matrix T2 between the beam coordinate system and the robot cusp coordinate system using the Rodrigues transformation (the process is similar to the calculation of T and will not be repeated). This gives the pose matrix of the cusp coordinate system in the beam coordinate system at this point:

[0123]

[0124] The vector formed by the third column of T2 is the direction of the tool axis in the beam coordinate system;

[0125] 7. The attitude transformation matrix between the tool coordinate system and the flange coordinate system is:

[0126]

[0127] The pose transformation matrix is:

[0128]

[0129] The tool coordinate system calibration is now complete.

[0130] Qt is a cross-platform C++ graphical user interface application framework. It provides application developers with all the features they need to create state-of-the-art graphical interfaces.

Claims

1. A method for robot end tool coordinate system calibration, characterized in that, Step one, install the calibration device: composed of an industrial robot, a calibration plate based on a laser emitting sensor, a calibration tool and an upper computer control system; the industrial robot is connected with the upper computer control system and the calibration plate based on the laser emitting sensor; the calibration tool is installed at the end of the flange of the industrial robot; Step two, complete the calibration process through the upper computer program controlled by the Qt interface development; Step three, manual teaching: align the calibration tool tip point installed at the end of the industrial robot flange with the intersection of the two laser beams emitted by the calibration plate based on the laser emitting sensor, so that the calibration tool tip point can block the two laser beams at the same time, and record the pose of the robot flange in the base coordinate system; Step four, calibration of the laser beam coordinate system: send motion instructions to the robot through the upper computer control software to execute the predetermined calibration action, the calibration tool tip point on the end flange of the robot, according to the preset motion program of the upper computer, gets the corresponding flange pose of the robot in the base coordinate system when the tip point blocks or connects the laser beam during the execution of the calibration action, and the relative pose of the laser beam coordinate system in the robot base coordinate system is fitted by algorithm, so as to convert the working space to the laser beam coordinate system; Step five, calibration of the tool coordinate system: replace the calibration tool on the end flange of the robot with the actual tool, align the tip point of the tool with the intersection of its laser beams, execute the preset action of the upper computer, get the corresponding pose data of the actual tool when connecting or breaking the light in the laser beam coordinate system, and the tool coordinate system of the actual tool can be obtained by fitting; the calibration is completed.

2. The method for robot end-effector coordinate system calibration according to claim 1, wherein, The manual teaching of step three is specifically: through the manual quick teaching function of the robot, adjust the mode to "flange surface parallel to the ground", and quickly adjust the tip point to the vertical downward state; adjust the position of the flange in the robot base coordinate system mode through the teach pendant, so that the tip point can block the laser emitted by the two sensors at the same time; record the coordinates of the center of the robot flange as [x0 y0 z0] at this time through the upper computer operation software; since the quick adjustment mode is used to make the flange surface parallel to the ground, the attitude is [180° 0° 180°].

3. The method for robot end-effector coordinate system calibration according to claim 1, wherein, The specific process of step four, calibration of the laser beam coordinate system, is that the operator sends the robot motion instructions through the upper computer software, and the robot carrying the high-precision tip point moves along the following trajectory: (a) the robot is lifted to 50mm above the laser beam plane; (b) through the upper computer, the real-time recording function of the robot pose is turned on, and at the same time, the tip point is translated by a proper distance R in the plane parallel to the XY plane of the base coordinate system, to ensure that the tip point will not cause the sensor to connect or break the light when it is lowered, and the tip point is lowered by 100mm along the Z axis of the robot base coordinate system, so that the connection between the cylindrical surface and the conical surface of the tip point is located 50mm below the laser beam plane; (c) The motion program for starting the calibration is controlled by the host computer: the robot flange keeps the posture of [180° 0° 180°], and moves along the whole circle trajectory with the center of [x0 y0 z0-50] and the radius of R. In the whole circle trajectory, the x and y groups of the pair of laser sensors occur four times of light interruption and four times of light connection. Through the interaction of the host computer software, the robot control system and the calibration plate sensor, the robot flange positions of the four times of light interruption are recorded as Dx1, Dy1, Dx2, Dy2, and the robot flange positions of the four times of light connection are recorded as Jx1, Jy1, Jx2, Jy2. Four groups of line segments are obtained by connecting the recorded eight positions: Dx1-Dx2, Jx1-Jx2, Dy1-Dy2, Jy1-Jy2, wherein the intersection of Dx1-Dx2 and Jx1-Jx2 is recorded as X1, and the intersection of Dy1-Dy2 and Jy1-Jy2 is recorded as Y1; (d) The center of [x0 y0 z0-60], [x0 y0 z0-70], [x0 y0 z0-80], [x0 y0 z0-90] is taken as the center, and the radius of R is taken as the radius to move along the whole circle trajectory. The light interruption and robot position recording steps in the third step are repeated to obtain the following space points in the robot base coordinate system: X2, Y2, X3, Y3, X4, Y4, X5, Y5; (e) Perform fitting, X1,X2,X3,X4,X5 to get straight line vector Y1,Y2,Y3,Y4,Y5 to get straight line vector And do the following processing: to the vector and Perform an isometric transformation to make the third element become 1, that is, transform to: (f) The following vectors are calculated: To unitize the processing: To calibrate the rod axis, i.e. the vector of the flange coordinate system Z axis in the beam coordinate system; (j) solving the angle a between the two vectors [0 0 1] The cross product of [001] and two vectors is: The posture conversion matrix between the light beam coordinate system and the robot tip point coordinate system is: In the flange coordinate system of the robot, the tip point is at a position of 150 mm along the Z axis of the flange coordinate system: P＝[0 0 150] The posture matrix of the flange center point in the light beam coordinate system is: The posture matrix of the flange center point in the robot base coordinate system is: The conversion relationship between the light beam coordinate system and the flange coordinate system is: By this time, the light beam coordinate system calibration is completed.

4. The method for robot end-effector coordinate system calibration of claim 1, wherein, The specific content of step five is: (a) Disassemble the calibration tip point fixed to the flange, replace it with a tool, manually align the intersection of the tool tip point and the two laser beams, and make the axis direction of the tip point approximately perpendicular to the laser beam plane. Record the robot flange center coordinates flangepoint2 = [x2 y2 z2] and Euler angles [A2 B2 C2] at this time; (b) Convert the Euler angles [A2 B2 C2] to the corresponding posture matrix R according to the order recognized by the robot control system, and form the following posture matrix: (c) The following matrix is calculated: Wherein the matrix T1 is the posture of the flange coordinate system in the light beam coordinate system, and the fourth column of the first three arrays forms a point coordinate resultpoint; (d) keeping the robot flange pose unchanged, the robot carrying the tool tip is rotated 5 times again, and the fitting vector is obtained by using the similar method of the obtained point cloud data and the calibration beam coordinate system (e) In the light beam coordinate system, the point coordinate resultpoint is the flange center coordinate, and the origin [0 00] is the tool point coordinate. The relative position of the two is the position of the origin of the tool coordinate system relative to the flange center. The origin information of the tool coordinate system is calibrated; (f) finding The angle between [0 0 1] and the normal vector of the plane is calculated, and the pose transformation matrix T2 between the beam coordinate system and the robot tip coordinate system is obtained by using the Rodrigues transformation. The pose matrix of the tip coordinate system in the beam coordinate system at this time is obtained. The vector composed of the third column of T2 is the direction of the tool axis in the light beam coordinate system; (j) The posture conversion matrix of the tool coordinate system and the flange coordinate system is: The posture conversion matrix is: By this time, the tool coordinate system calibration is completed.

5. The method for robot end-effector coordinate system calibration of claim 1, wherein, The calibration tool is composed of a flange adapter and a calibration sharp point, and the material is 45 steel; the size and distribution of the mounting hole of the flange adapter are determined according to the relevant size of the flange of the robot to be calibrated.

6. The method for robot end-effector coordinate system calibration of claim 1, wherein, The step one can be applied to industrial robots, collaborative robots and mechanical arms with high-speed IO ports and signal transmission communication functions.

7. The method for robot end-effector coordinate system calibration of claim 1, wherein, The laser transmission sensor on the calibration board interacts with the high-speed IO port of the robot in real time, so that the robot can communicate with the sensor signal, and the linkage between the robot pose and the light shielding point position is realized; the laser beam diameter of the laser transmission sensor is 0.5mm, the installation position accuracy is guaranteed by machining, the response time of the robot IO port is 4ms, and through experimental verification, when the programmed speed of the robot is not more than 20% of the maximum running speed, the light shielding and light receiving signals at each point can be accurately and timely received and analyzed, and the accurate matching between the robot pose and the signal is ensured.

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