A wrist joint offset type robot zero calibration device and method

Abstract

The present invention belongs to the field of robots, and specifically, is a wrist joint offset type robot zero calibration device and method, wherein the zero calibration device of the present invention includes a base plate, a zero calibration shaft and a rotating plate, the zero calibration shaft is plugged into a reference hole correspondingly opened on the robot forearm of the robot to be tested, the base plate is connected to the robot wrist of the robot to be tested, and the rotating plate is installed on the robot end effector connection flange of the robot to be tested. The matching arrangement between the base plate, the zero calibration shaft and the rotating plate, the robot forearm, the robot wrist and the robot end effector connection flange of the robot to be tested, which are precisely machined, is not affected by the excessive size of the wrist joint offset, and can obtain a higher calibration accuracy compared to the existing robot universal latch structure zero calibration method, and the calibration accuracy is related to the machining accuracy of the zero calibration device, and has little to do with the operator's operating experience, is convenient for ergonomic operation, is simple to use, and is easy to manufacture and maintain.

Description

Technical Field

[0001] The invention belongs to the field of robots, in particular to a zero calibration device and method for a wrist joint offset type robot. Background Art

[0002] In the past two decades, robot technology has developed very rapidly, and robots of various purposes have been widely used in various fields. In particular, six-axis industrial robots are widely used in the automotive industry, plastics industry, pharmaceutical industry, and food industry to complete operations such as grinding, handling, spraying, and welding to replace manual operations, liberate productivity, and improve production efficiency. The general application method of six-axis industrial robots is to add operating tools to the end of the wrist and realize flexible automation in the production process by controlling the robot.

[0003] The wrist joint is a robot component that connects the arm and the end effector. It is located at the end of the robot. Its function is to realize the three coordinate positions of the end effector in the working space by the wrist on the basis of the three coordinate positions of the end effector in the working space realized by the arm and waist. The wrist joint of the current industrial robot is limited by the mechanical structure and can only swing within the range of -125 degrees and +125 degrees, which is greatly limited. This will have a certain impact on the motion trajectory and continuity during the operation, and then affect the motion posture of the entire robotic arm. Therefore, the wrist joint offset robot realizes infinite rotation of four, five and six axes at the end of the robot. Improve the scope of application, such as grinding, spraying and other working conditions.

[0004] However, due to the wrist offset of the robot, the existing wrist zero calibration method of inserting a zero calibration pin will result in low accuracy due to the large wrist offset size. Therefore, a new wrist offset type robot zero calibration device and method is needed. Summary of the invention

[0005] In view of the above problems, an object of the present invention is to provide a zero calibration device and method for a wrist offset robot.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A wrist joint offset type robot zero calibration device, comprising a base plate, a zero calibration shaft and a rotating plate, wherein the zero calibration shaft is divided into a plug-in column part and a reference block part connected together, wherein the plug-in column part is plugged into a reference hole correspondingly opened on a robot forearm of a robot to be tested, wherein the base plate is divided into a reference test part A and a reference test part B connected together, wherein the reference test part A is embedded in a base plate mounting groove correspondingly opened on a robot wrist of the robot to be tested and fixed, wherein the rotating plate is divided into a rotating plate main body part and an extended test end part connected together, wherein the rotating plate main body part is mounted on a robot end effector connection flange of the robot to be tested;

[0008] A positioning side A is provided on the periphery of the reference stop block portion, a positioning side B is provided on the reference test B portion for being fitted with the positioning side A for zero calibration, a positioning side C is provided on the periphery of the extended test end portion, a plurality of positioning side D are provided on the reference test A portion, one of the positioning side D is fitted with the positioning side C for zero calibration, and the plane where the positioning side D is located is parallel to the plane where the positioning side B is located.

[0009] The axis centerline of the reference hole is parallel to the axis of the fifth axis of the robot to be tested and is orthogonal to the axis of the sixth axis of the robot to be tested. A reference plane A is provided on the robot arm at the periphery of the reference hole, and the plane where the reference plane A is located is orthogonal to the axis of the fifth axis of the robot to be tested;

[0010] The outer peripheral surface of the plug-in column portion of the zeroing shaft is a plug-in cylindrical surface, the plug-in cylindrical surface is gap-matched with the reference hole, the plug-in column portion is connected to the bottom surface of the reference block portion, and the bottom surface of the reference block portion outside the plug-in column portion forms a reference bottom surface A; after the plug-in cylindrical surface is plugged into the reference hole, the reference bottom surface A is in contact with the reference plane A.

[0011] The opening edge of the reference hole is provided with a chamfer A; the outer peripheral edge of the bottom end of the plug-in column is provided with a chamfer B.

[0012] The top surface of the reference stop block portion of the zeroing stop shaft serves as a screw connection surface, and a threaded hole A is provided on the screw connection surface, and a disassembly screw is threadedly connected to the threaded hole A.

[0013] The outer peripheral side surface of the reference stop block portion of the zeroing shaft is divided into two relatively arranged positioning side surfaces A and two relatively arranged large convex arc surfaces, and each of the large convex arc surfaces is connected to the adjacent positioning side surfaces A through a guide fillet A.

[0014] The bottom surface of the substrate installation groove is a reference bottom surface B, the plane where the reference bottom surface B is located is orthogonal to the axis of the fifth axis of the robot to be tested, a plurality of threaded holes B are provided on the reference bottom surface B, and the substrate installation groove has two opposite side surfaces as reference side surfaces A, and both of the two reference side surfaces A are parallel to the axis of the fifth axis of the robot to be tested;

[0015] A reference plane B and two positioning side surfaces D are respectively provided on the reference test part A of the substrate. A plurality of connecting screws A respectively connected to the threaded holes B are also passed through the reference test part A of the substrate. The reference plane B is in contact with the reference bottom surface B, and each positioning side surface D is respectively in contact with a corresponding reference side surface A.

[0016] The reference side surface A at the opening of the substrate installation groove is provided with a chamfer C, and the reference plane B is connected to the adjacent positioning side surfaces D through guide fillets B respectively.

[0017] The end surface of the connecting flange of the robot end effector is used as a reference plane C, the plane where the reference plane C is located is orthogonal to the axis of the sixth axis of the robot to be tested, and a plurality of threaded holes C are opened on the reference plane C;

[0018] One end surface of the rotating plate main body of the rotating plate serves as a reference bottom surface C, and the reference bottom surface C is in contact with the reference plane C. A plurality of connecting screws B respectively connected to the threaded holes C are also provided on the rotating plate main body of the rotating plate.

[0019] A plurality of pin holes are formed on the reference plane C, and a plurality of positioning pins respectively connected with the pin holes are also formed on the main body of the rotating plate.

[0020] A wrist joint offset type robot zero calibration method is implemented using the aforementioned wrist joint offset type robot zero calibration device, and the zero calibration method comprises the following steps:

[0021] Step 1. Connect the robot to be tested to the robot teaching pendant, rotate the fifth axis between the robot forearm and the robot wrist, move the robot wrist away from the robot forearm, and leave operating space for the base plate to be installed on the robot wrist;

[0022] Step 2. Install the base plate on the robot wrist, guide it through the guide fillet B and chamfer C, fit the reference plane B to the reference bottom surface B, fit the positioning side D to the reference side A, and make the connecting screw A enter the threaded hole B. Both the positioning side D and the positioning side B represent the spatial position and posture of the robot wrist;

[0023] Step 3. Install the zero-calibration shaft on the robot arm, guide it through chamfers B and A, insert the plug-in cylinder into the reference hole, and fit the reference bottom surface A and the reference plane A;

[0024] Step 4. Zero the robot arm and robot wrist, rotate the fifth axis between the robot arm and the robot wrist, let the positioning side B of the substrate collide with the guide fillet A, and rotate the zeroing shaft;

[0025] Step 5. Continuously measure the gap between positioning side B and positioning side A with a feeler gauge, and give the rotation input value of the fifth axis between the rotating robot arm and the robot wrist through the robot teaching pendant, and adjust from high speed, medium speed, low speed and micro speed in sequence to make the rotating robot arm and the robot wrist rotate relative to each other until positioning side B is completely fitted with positioning side A;

[0026] Step 6. Perform an optical re-inspection with a light transmittance meter, so that the light of the light transmittance meter is shone from one side of the gap between the positioning side B and the positioning side A, and re-inspect the light transmittance on the other side of the gap; if it is not transparent, it is qualified and proceed to the next step; if it is unqualified, return to step 2 and re-operate and adjust until it is qualified, and then proceed to the next step;

[0027] Step 7. Operate the robot teaching pendant to record the zero position of the fifth axis of the robot forearm and robot wrist;

[0028] Step 8. Adjust the axis of rotation of the robot wrist and the robot end effector connection flange, that is, the phase of the sixth axis of the robot to be tested, so that the rotating plate and the base plate do not interfere with each other after installation;

[0029] Step 9. Install the rotating plate on the connecting flange of the robot end effector, make the reference bottom surface C fit with the reference plane C, insert the positioning pin into the pin hole to lock the position and posture, and connect the connecting screw B with the threaded hole C;

[0030] Step 10. Zero the connection flanges of the robot wrist and the robot end effector, rotate the sixth axis of the robot to be tested, and make the positioning side C of the rotating plate collide with the positioning side D of the base plate;

[0031] Step 11. Continuously measure the gap between the positioning side C and the positioning side D with a feeler gauge, and give the sixth axis rotation input value of the robot wrist and the robot end effector connection flange through the robot teaching pendant, and adjust them in sequence from high speed, medium speed, low speed and micro motion to make the robot wrist and the robot end effector connection flange rotate relative to each other until the positioning side C and the positioning side D are completely fitted together;

[0032] Step 12. Perform an optical re-inspection with a light transmittance meter, so that the light of the light transmittance meter is shone from one side of the gap between the positioning side surface C and the positioning side surface D, and re-inspect the light transmittance on the other side of the gap; if it is not transparent, it is qualified and proceed to the next step; if it is unqualified, return to step 9 and re-operate and adjust until it is qualified, and then proceed to the next step;

[0033] Step 13. Operate the robot teaching pendant, robot wrist and robot end effector connection flange to zero position of the sixth axis;

[0034] Step 14. After zero calibration is completed, remove the base plate, zero calibration shaft and rotating plate.

[0035] The advantages and positive effects of the present invention are:

[0036] The present invention is not affected by excessive wrist joint offset size through the matching arrangement of the precisely machined base plate, zeroing shaft and rotating plate with the robot forearm, robot wrist and robot end effector connecting flange of the robot to be tested. Compared with the existing robot universal latch structure zeroing method, higher calibration accuracy can be obtained, and the calibration accuracy is related to the machining accuracy of the zeroing device and has little relationship with the operator's operating experience. It is convenient for ergonomic operation, simple to use, and easy to manufacture and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the overall configuration structure of the present invention;

[0038] Figure 2 for Figure 1 A magnified image of point A;

[0039] Figure 3 It is a schematic diagram of the structure of the rotating plate and the base plate of the present invention;

[0040] Figure 4 A schematic diagram of a partial three-dimensional structure of a wrist joint offset type robot to which the present invention is applicable;

[0041] Figure 5 A partial front view structural schematic diagram of a wrist offset robot to which the present invention is applicable;

[0042] Figure 6 It is a schematic diagram of the structure of part of the mechanical connection interface of the wrist offset type robot to which the present invention is applicable;

[0043] Figure 7 It is a schematic diagram of the three-dimensional structure of the present invention when in use.

[0044] In the figure: 1 is a base plate, 101 is a reference plane B, 102 is a positioning side surface D, 103 is a guide fillet B, 104 is a connecting screw A, and 105 is a positioning side surface B;

[0045] 2 is the zeroing shaft, 201 is the chamfer B, 202 is the plug-in cylindrical surface, 203 is the reference bottom surface A, 204 is the large convex arc surface, 205 is the guide fillet A, 206 is the positioning side surface A, 207 is the screw connection surface, and 208 is the disassembly screw;

[0046] 3 is a rotating plate, 301 is a reference bottom surface C, 302 is a positioning pin, 303 is a connecting screw B, and 304 is a positioning side surface C;

[0047] 4 is the robot arm, 401 is the reference hole, 402 is the reference plane A, and 403 is the chamfer A;

[0048] 5 is the robot wrist, 501 is the reference bottom surface B, 502 is the reference side surface A, 503 is the chamfer C, and 504 is the threaded hole B;

[0049] 6 is the robot end effector connection flange, 601 is the reference plane C, 602 is the pin hole, and 603 is the threaded hole C;

[0050] 7 is the fifth axis, and 8 is the sixth axis. DETAILED DESCRIPTION

[0051] The following is combined with Figure 1-7 The present invention is further described in detail.

[0052] A wrist joint offset type robot zero calibration device, such as Figure 1-7 As shown, the present embodiment includes a base plate 1, a zeroing shaft 2 and a rotating plate 3 which are formed by precision machining. The zeroing shaft 2 is divided into a plug-in column portion and a reference block portion which are connected together. The plug-in column portion is plugged into a reference hole 401 correspondingly opened on the robot arm 4 of the robot to be tested. The base plate 1 is in the shape of a long strip and is divided into a reference test portion A and a reference test portion B which are connected together. The reference test portion A is embedded in a base plate mounting groove correspondingly opened on the robot wrist 5 of the robot to be tested and fixed. The rotating plate 3 is divided into a rotating plate main body portion and an extended test end portion which are connected together. The rotating plate main body portion is in the shape of a circular plate, and the extended test end portion is a portion protruding from the circular plate-shaped rotating plate main body portion. The rotating plate main body portion is installed on the robot end effector connecting flange 6 of the robot to be tested.

[0053] The outer periphery of the reference stopper portion is provided with a positioning side surface A 206, the reference test portion B is provided with a positioning side surface B 105 for fitting with the positioning side surface A 206 for zero calibration, the outer periphery of the extended test end is provided with a positioning side surface C 304, and the reference test portion A has two positioning side surfaces D 102, one of which fits with the positioning side surface C 304 for zero calibration, and the planes where the positioning side surfaces D 102 are located are parallel to the plane where the positioning side surface B 105 is located. The positioning side surface A 206, the positioning side surface B 105, the positioning side surface C 304 and the positioning side surface D 102 are all precision-machined matching planes.

[0054] Specifically, in this embodiment, the axis centerline of the reference hole 401 is parallel to the fifth axis axis 7 of the robot to be tested and is orthogonal to the sixth axis axis 8 of the robot to be tested. A reference plane A402 is provided on the robot arm 4 at the periphery of the reference hole 401. The plane where the reference plane A402 is located is orthogonal to the fifth axis axis 7 of the robot to be tested. The reference plane A402 is a precision-machined matching plane.

[0055] The outer peripheral surface of the plug-in column of the zeroing shaft 2 is a plug-in cylindrical surface 202, which is clearance-matched with the reference hole 401, and the plug-in column is connected to the bottom surface of the reference block portion, and the bottom surface of the reference block portion outside the plug-in column forms a reference bottom surface A203; after the plug-in cylindrical surface 202 is plugged into the reference hole 401, the reference bottom surface A203 is in contact with the reference plane A402. The opening edge of the reference hole 401 is provided with a chamfer A403; the outer peripheral edge of the bottom end of the plug-in column is provided with a chamfer B201.

[0056] The outer peripheral side surface of the reference stop block portion of the zero calibration shaft 2 is divided into two oppositely arranged positioning side surfaces A 206 and two oppositely arranged large convex arc surfaces 204, and each large convex arc surface 604 is connected to the adjacent positioning side surface A 206 through a guide fillet A 205. During zero calibration, one of the positioning side surfaces A 206 is in contact with the positioning side surface B 105.

[0057] The top surface of the reference stopper of the zeroing gear shaft 2 is used as a screw connection surface 207, and a threaded hole A is provided on the screw connection surface 207, and a disassembly screw 208 is threadedly connected to the threaded hole A. The disassembly screw 208 is provided to facilitate the disassembly screw 208 to be clamped by pliers and the zeroing gear shaft 2 to be removed, so as to prevent damage to the positioning side surface A 206 of the zeroing gear shaft 2.

[0058] Specifically, in this embodiment, the bottom surface of the substrate installation groove is a reference bottom surface B501, the plane where the reference bottom surface B501 is located is orthogonal to the fifth axis axis 7 of the robot to be tested, a plurality of threaded holes B504 are provided on the reference bottom surface B501, and the substrate installation groove has two opposite side surfaces as reference side surfaces A502, and both reference side surfaces A502 are parallel to the fifth axis axis 7 of the robot to be tested. The reference bottom surface B501 is a matching plane formed by precision machining.

[0059] The reference test part A of the substrate 1 is provided with a reference plane B 101 and two positioning side surfaces D 102. The reference test part A of the substrate 1 is also provided with a plurality of connecting screws A 104 respectively connected to the threaded holes B 504. The reference plane B 101 is fitted with the reference bottom surface B 501, and each positioning side surface D 102 is fitted with a corresponding reference side surface A 502. The reference side surface A 502 at the opening of the substrate mounting groove is provided with a chamfer C 503, and the reference plane B 101 is respectively connected with the adjacent positioning side surfaces D 102 through the guide fillet B 103.

[0060] Specifically, in this embodiment, the end surface of the robot end effector connection flange 6 is used as the reference plane C 601, the plane where the reference plane C 601 is located is orthogonal to the sixth axis 8 of the robot to be tested, and a plurality of threaded holes C 603 are provided on the reference plane C 601. The reference plane C 601 is a precision-machined matching plane.

[0061] One end surface of the rotating plate body of the rotating plate 3 is used as the reference bottom surface C 301, and the reference bottom surface C 301 is in contact with the reference plane C601. The rotating plate body of the rotating plate 3 is also provided with a plurality of connecting screws B303 respectively connected with the threaded holes C 603. The reference plane C 601 is provided with a plurality of pin holes 602, and the rotating plate body of the rotating plate 3 is also provided with a plurality of positioning pins 302 respectively connected with the pin holes 602.

[0062] A wrist joint offset type robot zero calibration method is implemented using the wrist joint offset type robot zero calibration device described above, and the zero calibration method comprises the following steps:

[0063] Step 1. Connect the robot to be tested to the robot teaching pendant, rotate the fifth axis between the robot arm 4 and the robot wrist 5, move the robot wrist 5 away from the robot arm 4, and leave operating space for the substrate 1 to be installed on the robot wrist 5;

[0064] Step 2. Install the substrate 1 on the robot wrist 5, guide it through the guide fillet B 103 and the chamfer C 503, fit the reference plane B 101 to the reference bottom surface B 501, fit the positioning side D 102 to the reference side A 502, and make the connecting screw A 104 enter the threaded hole B 504. The positioning side D 102 and the positioning side B 105 both represent the spatial position and posture of the robot wrist 5;

[0065] Step 3. Install the zero-calibration shaft 2 on the robot arm 4, guide it through the chamfer B 201 and the chamfer A 403, insert the plug-in cylindrical surface 202 into the reference hole 401, and fit the reference bottom surface A 203 and the reference plane A 402;

[0066] Step 4. The robot arm 4 and the robot wrist 5 are zeroed, and the fifth axis between the robot arm 4 and the robot wrist 5 is rotated so that the positioning side B 105 of the substrate 1 conflicts with the guide fillet A 205, and the zeroing shaft 2 is rotated;

[0067] Step 5. Continuously measure the gap between the positioning side B 105 and the positioning side A 206 with a feeler gauge, and give the rotation input value of the fifth axis between the rotating robot arm 4 and the robot wrist 5 through the robot teaching pendant, and adjust in sequence from high speed, medium speed, low speed and micro motion to make the rotating robot arm 4 and the robot wrist 5 rotate relative to each other until the positioning side B 105 and the positioning side A 206 are completely fitted together;

[0068] Step 6. Perform an optical re-inspection using a transmittance meter, so that the light of the transmittance meter is shone from one side of the gap between the positioning side surface B 105 and the positioning side surface A 206, and re-inspect the transmittance of the other side of the gap; if it is not transparent, it is qualified and proceed to the next step; if it is unqualified, return to step 2 and re-operate and adjust until it is qualified, and then proceed to the next step;

[0069] Step 7. Operate the robot teaching pendant to record the zero position of the fifth axis of the robot arm 4 and the robot wrist 5;

[0070] Step 8. Adjust the axis of rotation of the robot wrist 5 and the robot end effector connection flange 6, that is, the phase of the sixth axis of the robot to be tested, so that the rotating plate 3 and the base plate 1 do not interfere with each other after installation;

[0071] Step 9. Install the rotating plate 3 on the connecting flange 6 of the robot end effector, so that the reference bottom surface C 301 is aligned with the reference plane C 601, the positioning pin 302 is inserted into the pin hole 602 to lock the position and posture, and the connecting screw B 303 is connected to the threaded hole C603;

[0072] Step 10. The robot wrist 5 and the robot end effector connection flange 6 are zeroed, and the sixth axis of the robot to be tested is rotated so that the positioning side surface C 304 of the rotating plate 3 conflicts with the positioning side surface D 102 of the base plate 1;

[0073] Step 11. Continuously measure the gap between the positioning side surface C 304 and the positioning side surface D 102 with a feeler gauge, and give the sixth axis rotation input value of the robot wrist 5 and the robot end effector connection flange 6 through the robot teaching pendant, and adjust them in sequence from high speed, medium speed, low speed and micro motion to make the robot wrist 5 and the robot end effector connection flange 6 rotate relative to each other until the positioning side surface C 304 is completely fitted with the positioning side surface D 102;

[0074] Step 12. Perform an optical re-inspection using a light transmittance meter, so that the light of the light transmittance meter is shone from one side of the gap between the positioning side surface C 304 and the positioning side surface D 102, and re-inspect the light transmittance on the other side of the gap; if it is not transparent, it is qualified and proceed to the next step; if it is not qualified, return to step 9 and re-operate and adjust until it is qualified, and then proceed to the next step;

[0075] Step 13. Operate the robot teaching pendant, the robot wrist 5 and the robot end effector connecting flange 6 to the zero position of the sixth axis;

[0076] Step 14. After the zero calibration is completed, remove the base plate 1, the zero calibration shaft 2 and the rotating plate 3.

[0077] Working principle:

[0078] The matching arrangement between the precisely machined base plate 1, the zeroing shaft 2 and the rotating plate 3 and the robot forearm 4, the robot wrist 5 and the robot end effector connecting flange 6 of the robot to be tested is not affected by the excessive offset size of the wrist joint. Compared with the existing robot universal latch structure zeroing method, a higher calibration accuracy can be obtained, and the calibration accuracy is related to the machining accuracy of the zeroing device and has little relationship with the operator's operating experience. It is convenient for ergonomic operation, simple to use, and easy to manufacture and maintain.

Claims

1. A wrist joint offset robot zero calibration device, Features: The invention comprises a base plate (1), a zeroing gear shaft (2) and a rotating plate (3), wherein the zeroing gear shaft (2) is divided into a plug-in column portion and a reference block portion connected together, the plug-in column portion is plugged into a reference hole (401) correspondingly provided on a robot forearm (4) of a robot to be tested, the base plate (1) is divided into a reference test portion A and a reference test portion B connected together, the reference test portion A is embedded in a base plate mounting groove correspondingly provided on a robot wrist (5) of the robot to be tested and fixed, and the rotating plate (3) is divided into a rotating plate main body portion and an extended test end portion connected together, and the rotating plate main body portion is mounted on a robot end effector connection flange (6) of the robot to be tested; The outer periphery of the reference stop block portion is provided with a positioning side surface A (206), the reference test B portion is provided with a positioning side surface B (105) for being fitted with the positioning side surface A (206) for zero calibration, the outer periphery of the extended test end portion is provided with a positioning side surface C (304), the reference test A portion is provided with a plurality of positioning side surfaces D (102), one of the positioning side surfaces D (102) is fitted with the positioning side surface C (304) for zero calibration, and the plane where the positioning side surface D (102) is located is parallel to the plane where the positioning side surface B (105) is located; The axis centerline of the reference hole (401) is parallel to the axis line (7) of the fifth axis of the robot to be tested and is orthogonal to the axis line (8) of the sixth axis of the robot to be tested; a reference plane A (402) is provided on the robot arm (4) at the periphery of the reference hole (401); the plane where the reference plane A (402) is located is orthogonal to the axis line (7) of the fifth axis of the robot to be tested; The outer peripheral surface of the plug-in column portion of the zeroing shaft (2) is a plug-in cylindrical surface (202), the plug-in cylindrical surface (202) is clearance-matched with the reference hole (401), the plug-in column portion is connected to the bottom surface of the reference block portion, and the bottom surface of the reference block portion outside the plug-in column portion forms a reference bottom surface A (203); after the plug-in cylindrical surface (202) is plugged into the reference hole (401), the reference bottom surface A (203) and the reference plane A (402) are in contact.

2. The wrist joint offset type robot zero calibration device according to claim 1, Features: The opening edge of the reference hole (401) is provided with a chamfer A (403); the outer peripheral edge of the bottom end of the plug-in column portion is provided with a chamfer B (201).

3. The wrist joint offset type robot zero calibration device according to claim 1, Features: The top surface of the reference stop block portion of the zero-calibration stop shaft (2) serves as a screw connection surface (207), a threaded hole A is provided on the screw connection surface (207), and a disassembly screw (208) is threadedly connected to the threaded hole A.

4. The wrist joint offset type robot zero calibration device according to claim 1, Features: The outer peripheral side surface of the reference stop block portion of the zero-calibration stop shaft (2) is divided into two relatively arranged positioning side surfaces A (206) and two relatively arranged large convex arc surfaces (204), and each of the large convex arc surfaces (204) is connected to an adjacent positioning side surface A (206) via a guide fillet A (205).

5. The wrist joint offset type robot zero calibration device according to claim 1, Features: The bottom surface of the substrate installation groove is a reference bottom surface B (501), the plane where the reference bottom surface B (501) is located is orthogonal to the fifth axis axis (7) of the robot to be tested, a plurality of threaded holes B (504) are provided on the reference bottom surface B (501), and the substrate installation groove has two opposite side surfaces as reference side surfaces A (502), and both of the two reference side surfaces A (502) are parallel to the fifth axis axis (7) of the robot to be tested; A reference plane B (101) and two positioning side surfaces D (102) are respectively provided on the reference test portion A of the substrate (1). A plurality of connecting screws A (104) respectively connected to the threaded holes B (504) are also penetrated on the reference test portion A of the substrate (1). The reference plane B (101) is in contact with the reference bottom surface B (501), and each positioning side surface D (102) is respectively in contact with a corresponding reference side surface A (502).

6. The wrist joint offset type robot zero calibration device according to claim 5, Features: The reference side surface A (502) at the opening of the substrate mounting groove is provided with a chamfer C (503), and the reference plane B (101) is respectively connected to the adjacent positioning side surfaces D (102) via guide fillets B (103).

7. The wrist joint offset type robot zero calibration device according to claim 1, Features: The end surface of the connecting flange (6) of the robot end effector is used as a reference plane C (601), the plane where the reference plane C (601) is located is orthogonal to the sixth axis (8) of the robot to be tested, and a plurality of threaded holes C (603) are formed on the reference plane C (601); One end surface of the rotating plate main body of the rotating plate (3) serves as a reference bottom surface C (301), and the reference bottom surface C (301) is in contact with the reference plane C (601). The rotating plate main body of the rotating plate (3) is also provided with a plurality of connecting screws B (303) respectively connected to the threaded holes C (603).

8. The wrist joint offset type robot zero calibration device according to claim 7, Features: A plurality of pin holes (602) are provided on the reference plane C (601), and a plurality of positioning pins (302) respectively connected to the pin holes (602) are also provided on the rotating plate main body of the rotating plate (3).

9. A zero calibration method for a wrist offset robot. It is characterized in that The zero calibration method is implemented by using the wrist offset robot zero calibration device according to any one of claims 1 to 8, and the zero calibration method comprises the following steps: Step 1. Connect the robot to be tested to the robot teaching pendant, rotate the fifth axis between the robot arm (4) and the robot wrist (5), move the robot wrist (5) away from the robot arm (4), and leave operating space for the base plate (1) to be installed on the robot wrist (5); Step 2. Install the base plate (1) on the robot wrist (5), guide it through the guide fillet B (103) and the chamfer C (503), fit the reference plane B (101) to the reference bottom surface B (501), fit the positioning side surface D (102) to the reference side surface A (502), and make the connecting screw A (104) enter the threaded hole B (504). The positioning side surface D (102) and the positioning side surface B (105) both represent the spatial position and posture of the robot wrist (5); Step 3. Install the zero-calibration shaft (2) on the robot arm (4), guide it through the chamfer B (201) and the chamfer A (403), insert the plug-in cylindrical surface (202) into the reference hole (401), and fit the reference bottom surface A (203) and the reference plane A (402); Step 4. The robot arm (4) and the robot wrist (5) are zeroed, and the fifth axis between the robot arm (4) and the robot wrist (5) is rotated so that the positioning side surface B (105) of the base plate (1) contacts the guide fillet A (205), and the zeroing shaft (2) is rotated; Step 5. Continuously measure the gap between the positioning side surface B (105) and the positioning side surface A (206) with a feeler gauge, and provide the rotation input value of the fifth axis between the rotating robot arm (4) and the robot wrist (5) through the robot teaching device, and adjust in sequence from high speed, medium speed, low speed and micro motion to make the rotating robot arm (4) and the robot wrist (5) rotate relative to each other until the positioning side surface B (105) and the positioning side surface A (206) are completely fitted together; Step 6. Perform an optical re-inspection using a light transmittance meter, so that the light of the light transmittance meter is shone from one side of the gap between the positioning side surface B (105) and the positioning side surface A (206), and re-inspect the light transmittance on the other side of the gap; if it is not transparent, it is qualified and proceed to the next step; if it is not qualified, return to step 2 and re-operate and adjust until it is qualified, and then proceed to the next step; Step 7. Operate the robot teaching pendant to record the zero position of the fifth axis of the robot arm (4) and the robot wrist (5); Step 8. Adjust the axis of rotation of the robot wrist (5) and the robot end effector connection flange (6), that is, the phase of the sixth axis of the robot to be tested, so that the rotating plate (3) and the base plate (1) do not interfere with each other after installation; Step 9. Install the rotating plate (3) on the connecting flange (6) of the robot end effector, so that the reference bottom surface C (301) and the reference plane C (601) are aligned, the positioning pin (302) is inserted into the pin hole (602) to lock the position and posture, and the connecting screw B (303) is connected to the threaded hole C (603); Step 10. The robot wrist (5) and the robot end effector connection flange (6) are zeroed, and the sixth axis of the robot to be tested is rotated so that the positioning side surface C (304) of the rotating plate (3) is in contact with the positioning side surface D (102) of the base plate (1); Step 11. Continuously measure the gap between the positioning side surface C (304) and the positioning side surface D (102) with a feeler gauge, and provide the sixth axis rotation input value of the robot wrist (5) and the robot end effector connection flange (6) through the robot teaching device, and adjust in sequence from high speed, medium speed, low speed and micro-motion to make the robot wrist (5) and the robot end effector connection flange (6) rotate relative to each other until the positioning side surface C (304) and the positioning side surface D (102) are completely fitted together; Step 12. Perform an optical re-inspection using a light transmittance meter, so that the light of the light transmittance meter is shone from one side of the gap between the positioning side surface C (304) and the positioning side surface D (102), and re-inspect the light transmittance on the other side of the gap; if it is not transparent, it is qualified and proceed to the next step; if it is not qualified, return to step 9 and re-operate and adjust until it is qualified, and then proceed to the next step; Step 13. Operate the robot teaching pendant, the robot wrist (5) and the robot end effector connecting flange (6) to the zero position of the sixth axis; Step 14. After the zero calibration is completed, remove the base plate (1), the zero calibration shaft (2) and the rotating plate (3).

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