Dual-arm robot dynamic calibration device and calibration method based on preset trajectory

Abstract

The application discloses a preset trajectory-based dual-arm manipulator dynamic calibration device and method, relates to the wafer conveying field, and comprises: a guide moving piece for providing and restricting a preset linear motion trajectory; a supporting piece connected with the guide moving piece and capable of being controlled to move along the linear motion trajectory; two symmetrically arranged floating connecting pieces installed on the supporting piece, the floating connecting pieces being located on two sides of the linear motion trajectory and being detachably rigidly connected with the end joints of two arms respectively; wherein each floating connecting piece is capable of rotating around an axis perpendicular to the linear motion trajectory and adaptively floating in the direction of the axis; when the supporting piece moves along the linear motion trajectory, the two floating connecting pieces can simultaneously pull the two arms to synchronously stretch or contract along the linear motion trajectory. By adopting the above scheme, the dual arms can be quickly calibrated in a multi-source error superposition environment to realize the stable consistency of the dual-arm motion trajectories.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor wafer transfer equipment, and particularly relates to a preset trajectory-based dual-arm robot dynamic calibration device and method. BACKGROUND

[0002] In the industry trend of intelligent manufacturing and continuous development of high-end equipment, dual-arm robots gradually become the key execution subject of high-beat, high-precision handling and assembly tasks in automatic production lines due to their parallel execution, collaborative motion and spatial coordination capabilities. With the increasing demand for high-precision semiconductor wafer transfer, flexible manufacturing and complex scene collaborative operation, the synchronization, spatial consistency and trajectory collaboration of dual-arm robots are put forward with more stringent technical requirements. The geometric consistency and dynamic motion symmetry between the two arms are directly related to the safety, stability and beat performance of the whole line.

[0003] However, while the structure system of the dual-arm robot is continuously developing in the direction of high degrees of freedom, high load ratio and light weight, the complexity of its mechanical link is significantly improved: the multi-joint series structure causes the error transmission path to be longer, and the structural displacement introduced by flexible components further aggravates the dynamic deviation between the left and right arms. At the same time, factors such as manufacturing and assembly tolerances, thermal drift, and structural stress deformation may cause the motion trajectories of the dual arms to be inconsistent in actual operation. In the absence of an effective symmetry regulation mechanism, even dual-arm robots of the same model and assembly process cannot guarantee stable and consistent collaborative trajectories in long-term operation.

[0004] More prominently, the symmetry control of existing dual-arm robots mostly relies on structural static precision or factory installation consistency to maintain, but in the face of dynamic coupling errors under complex working conditions, nonlinear deviations caused by load changes, and small deviation accumulation in multi-degree-of-freedom coupled motion, traditional solutions relying on inherent structural precision or static alignment are difficult to compensate or close-loop regulate these dynamic errors in real time. Especially in scenes requiring high-speed beat, spatial coordination, or mirror trajectory motion of dual arms, how to achieve stable consistency of dual-arm motion trajectories in a multi-source error superposition environment has become a key problem that has long been unable to effectively break through in existing technology, and is also the core technical bottleneck to be solved by the present application. SUMMARY

[0005] The present application aims to provide a preset trajectory-based dual-arm robot dynamic calibration device and method to solve the problem of how to quickly calibrate dual arms to achieve stable consistency of dual-arm motion trajectories in a multi-source error superposition environment in the prior art.

[0006] To achieve the above-mentioned purpose, the technical solutions of the present application are as follows:

[0007] In a first aspect, a preset trajectory-based dynamic calibration device for a dual-arm robot is provided, which is applied to a robot having two independently extendable or retractable arms, and comprises:

[0008] a guiding moving part for providing and restricting a preset straight-line motion trajectory;

[0009] a supporting part connected with the guiding moving part and capable of being controlled to move along the straight-line motion trajectory;

[0010] two symmetrically arranged floating connecting parts mounted on the supporting part, the floating connecting parts being located on both sides of the straight-line motion trajectory and being detachably rigidly connected with the end joints of the two arms, respectively;

[0011] wherein each of the floating connecting parts is capable of rotating around an axis perpendicular to the straight-line motion trajectory and adaptively floating along the direction of the axis; when the supporting part is controlled to move along the straight-line motion trajectory, the two floating connecting parts can adaptively float and rotate while synchronously driving the two arms to extend or retract along the straight-line motion trajectory.

[0012] Further, the guiding moving part comprises a mounting plate, a guide rail arranged on the mounting plate, and a sliding block in sliding cooperation with the guide rail, the sliding block being fixedly connected with the supporting part, and the guide rail extending horizontally along the straight-line motion trajectory.

[0013] Further, the supporting part comprises a supporting seat and a rotating cooperation part, the supporting seat being provided with a through mounting hole in a vertical direction, and the rotating cooperation part being mounted in the through mounting hole, and part of the floating connecting part being located in the through mounting hole and rotatably connected with the rotating cooperation part.

[0014] Further, the rotating cooperation part is a bearing, the bearing comprising an inner ring and an outer ring arranged coaxially and capable of relative rotation, the outer ring of the bearing being fixedly connected with the supporting part, and the inner ring of the bearing being in clearance fit with the floating connecting part.

[0015] Further, the floating connecting part comprises a rotating shaft and a rotating disc arranged coaxially, the rotating disc having a diameter greater than that of the rotating shaft, the rotating shaft being fixedly connected with the rotating disc, and the rotating shaft penetrating the inner ring of the bearing.

[0016] Further, the rotating shaft comprises a telescopic part and a limiting part arranged coaxially, the telescopic part having a diameter smaller than that of the limiting part, the limiting part being located between the rotating disc and the telescopic part, and the diameter of the vertical projection of the limiting part being greater than the inner diameter of the inner ring.

[0017] Further, the support base comprises a fixed part and first and second supporting parts integrally formed and symmetrically arranged on both sides of the fixed part, the through mounting holes are respectively located on the first and second supporting parts, the first and second supporting parts radially protrude inwardly along the hole inner wall of the through mounting holes to form a ring-shaped stop ring, and the stop ring abuts against one end surface of the outer ring of the bearing.

[0018] Further, a guide groove is formed on the side of the fixed part away from the guide moving part and parallel to the linear motion trajectory, and the sliding block is embedded in the guide groove.

[0019] Further, a position adjusting part is arranged between the supporting part and the guide moving part, and the position adjusting part is used to finely adjust the installation position of the supporting part on the guide moving part.

[0020] Further, a plurality of spaced waist-shaped holes are formed on the supporting part along the vertical direction, the waist-shaped holes extend along the length direction of the supporting part, the position adjusting part comprises a fastening bolt penetrating through the waist-shaped hole and connected with the supporting part and a fastening stud, an adjusting hole is formed on the supporting part and communicates with the guide groove, and the fastening stud is threadedly connected with the adjusting hole.

[0021] Further, the first supporting part is detachably connected with a first compression cover, the second supporting part is detachably connected with a second compression cover, and the first and second compression covers are located between the floating connecting part and the supporting part and are used to fix the outer ring of the bearing.

[0022] In a second aspect, a dynamic calibration method of a dual-arm manipulator is provided, which utilizes the above-mentioned dynamic calibration device of a dual-arm manipulator based on a preset trajectory, and comprises the following steps:

[0023] Loosen the fasteners of the joints of the manipulator arm, so that each joint has a movement allowance within a predetermined angle range;

[0024] Drive the supporting part to move along the linear motion trajectory, synchronously drive the two arms to stretch or contract through the two floating connecting parts, and in this process, each joint is adaptively adjusted based on the rotation and floating of the floating connecting part to release the mechanical clearance and calibrate the motion trajectory;

[0025] Lock the fasteners of each joint to fix the calibrated posture;

[0026] Release the rigid connection between the floating connecting part and the arm.

[0027] The preset track based dual-arm robot dynamic calibration device provided by the application has the beneficial effects that: a stable, determined and high-precision linear motion track is constructed by the guide moving piece, and the support piece moves along the track under control, so that the calibration process is performed on a space-restricted geometric reference. The external reference effectively avoids the track drift and accumulated error caused by the independent movement of the dual arms. The two symmetrical floating connecting pieces have the freedom of rotation around the axis perpendicular to the linear track and floating along the axis direction, can automatically absorb the offset caused by the initial posture difference, structural relaxation, manufacturing and assembly tolerances and the like between the dual arms during the traction movement of the support piece, and realize the direct and synchronous traction of the dual-arm ends through the rigid connection mode, so that the two arms gradually tend to be consistent in the geometric posture under the guidance of the controlled external force. The "self-adaptive rotation + axial floating" connection structure of the technical solution realizes the dynamic passive compensation of the cooperative alignment of the dual arms, and further quickly calibrates the dual arms to realize the stability and consistency of the dual-arm motion track.

[0028] The preset track based dual-arm robot dynamic calibration device provided by the application has the beneficial effects that: a stable, determined and high-precision linear motion track is constructed by the guide moving piece, and the support piece moves along the track under control, so that the calibration process is performed on a space-restricted geometric reference. The external reference effectively avoids the track drift and accumulated error caused by the independent movement of the dual arms. The two symmetrical floating connecting pieces have the freedom of rotation around the axis perpendicular to the linear track and floating along the axis direction, can automatically absorb the offset caused by the initial posture difference, structural relaxation, manufacturing and assembly tolerances and the like between the dual arms during the traction movement of the support piece, and realize the direct and synchronous traction of the dual-arm ends through the rigid connection mode, so that the two arms gradually tend to be consistent in the geometric posture under the guidance of the controlled external force. The "self-adaptive rotation + axial floating" connection structure of the technical solution realizes the dynamic passive compensation of the cooperative alignment of the dual arms, and further quickly calibrates the dual arms to realize the stability and consistency of the dual-arm motion track. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 The preset track based dual-arm robot dynamic calibration device provided by the application has the beneficial effects that: a stable, determined and high-precision linear motion track is constructed by the guide moving piece, and the support piece moves along the track under control, so that the calibration process is performed on a space-restricted geometric reference. The external reference effectively avoids the track drift and accumulated error caused by the independent movement of the dual arms. The two symmetrical floating connecting pieces have the freedom of rotation around the axis perpendicular to the linear track and floating along the axis direction, can automatically absorb the offset caused by the initial posture difference, structural relaxation, manufacturing and assembly tolerances and the like between the dual arms during the traction movement of the support piece, and realize the direct and synchronous traction of the dual-arm ends through the rigid connection mode, so that the two arms gradually tend to be consistent in the geometric posture under the guidance of the controlled external force. The "self-adaptive rotation + axial floating" connection structure of the technical solution realizes the dynamic passive compensation of the cooperative alignment of the dual arms, and further quickly calibrates the dual arms to realize the stability and consistency of the dual-arm motion track.

[0030] Figure 2 The preset track based dual-arm robot dynamic calibration device provided by the application has the beneficial effects that: a stable, determined and high-precision linear motion track is constructed by the guide moving piece, and the support piece moves along the track under control, so that the calibration process is performed on a space-restricted geometric reference. The external reference effectively avoids the track drift and accumulated error caused by the independent movement of the dual arms. The two symmetrical floating connecting pieces have the freedom of rotation around the axis perpendicular to the linear track and floating along the axis direction, can automatically absorb the offset caused by the initial posture difference, structural relaxation, manufacturing and assembly tolerances and the like between the dual arms during the traction movement of the support piece, and realize the direct and synchronous traction of the dual-arm ends through the rigid connection mode, so that the two arms gradually tend to be consistent in the geometric posture under the guidance of the controlled external force. The "self-adaptive rotation + axial floating" connection structure of the technical solution realizes the dynamic passive compensation of the cooperative alignment of the dual arms, and further quickly calibrates the dual arms to realize the stability and consistency of the dual-arm motion track.

[0031] Figure 3 The preset track based dual-arm robot dynamic calibration device provided by the application has the beneficial effects that: a stable, determined and high-precision linear motion track is constructed by the guide moving piece, and the support piece moves along the track under control, so that the calibration process is performed on a space-restricted geometric reference. The external reference effectively avoids the track drift and accumulated error caused by the independent movement of the dual arms. The two symmetrical floating connecting pieces have the freedom of rotation around the axis perpendicular to the linear track and floating along the axis direction, can automatically absorb the offset caused by the initial posture difference, structural relaxation, manufacturing and assembly tolerances and the like between the dual arms during the traction movement of the support piece, and realize the direct and synchronous traction of the dual-arm ends through the rigid connection mode, so that the two arms gradually tend to be consistent in the geometric posture under the guidance of the controlled external force. The "self-adaptive rotation + axial floating" connection structure of the technical solution realizes the dynamic passive compensation of the cooperative alignment of the dual arms, and further quickly calibrates the dual arms to realize the stability and consistency of the dual-arm motion track.

[0032] Figure 4 The overall structure schematic diagram of the dynamic calibration device of the embodiment of the present application;

[0033] Figure 5 The top view of the dynamic calibration device of the embodiment of the present application;

[0034] Figure 6 The structure schematic diagram of the support of the embodiment of the present application;

[0035] Figure 7 The explosion view of the support and the floating connecting piece of the embodiment of the present application;

[0036] Figure 8 The sectional view of the support and the floating connecting piece of the embodiment of the present application;

[0037] Figure 9 The explosion view of the slider and the support of the embodiment of the present application;

[0038] Figure 10 The structure schematic diagram of the guiding moving piece of the embodiment of the present application;

[0039] Figure 11 The side view of the dual-arm manipulator of the embodiment of the present application.

[0040] The figure mark: 1, guiding moving piece; 11, straight line motion trajectory; 12, mounting plate; 121, fixed hole; 13, guide rail; 131, eccentric positioning pin; 14, slider; 2, support; 21, support seat; 211, fixed part; 2111, guiding groove; 2112, waist type hole; 2113, adjusting hole; 212, first supporting part; 2121, first gland; 213, second supporting part; 2122, second gland; 214, blocking ring; 215, through mounting hole; 22, rotation matching part; 221, outer ring; 222, inner ring; 3, floating connecting piece; 31, rotating shaft; 311, telescopic part; 312, limiting part; 32, rotating disc; 321, positioning hole; 322, positioning pin; 323, screw; 4, end joint; 5, position adjusting piece; 51, fastening bolt; 52, fastening jackscrew; 6, body; 7, first arm; 71, first upper arm; 72, first forearm; 73, first end effector; 8, second arm; 81, second upper arm; 82, second forearm; 83, second end effector. DETAILED DESCRIPTION

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but does not exclude other elements or objects.

[0042] The following is in conjunction with the appendix Figure 1 - Appendix Figure 11 The specific embodiments of the present invention will be further described in detail below.

[0043] Reference Figures 1-3 A dynamic calibration device for a dual-arm robotic hand based on a preset trajectory is applied to a dual-arm robotic hand with two arms that can extend or retract independently. The dual-arm robotic hand includes a body 6 and a first arm 7 and a second arm 8 pivotally connected to the body 6. The body 6 has a rotation axis X, from which a preset direction is extended to form the reference trajectory direction when the robotic arms extend or retract. The first arm 7 includes a first upper arm 71, a first forearm 72, and a first end effector 73, and sequentially has a first shoulder axis SX1, a first elbow axis EX1, and a first wrist joint axis WX1. The second arm 8, a mirror image of the first arm 7, includes a second upper arm 81, a second forearm 82, and a second end effector 83, and has a second shoulder axis SX2, a second elbow axis EX2, and a second wrist joint axis WX2.

[0044] In some specific embodiments of the present invention, the dynamic calibration device is such as Figure 1 As shown, the robot includes a guide moving part 1, a support part 2 connected to the guide moving part 1 and controllably movable along a preset linear motion trajectory 11, and two symmetrically arranged floating connecting parts 3 mounted on the support part 2. The first arm 7 and the second arm 8 can both extend or retract independently along the preset direction D1, their movement paths being parallel to the preset linear motion trajectory 11 described later. It is necessary to ensure that the wrist joint axes of both arms have an equal distance from the center line of the slider 14 in the initial state. Both arms can extend or retract along the preset direction D1 respectively, and their overall movement paths are parallel to the preset trajectory. To achieve consistency in the trajectories of the two arms, it is necessary to ensure that the distances from the axes of the two wrist joints to the preset trajectory are strictly equal, thereby maintaining the left-right symmetrical kinematic characteristics of the robot during its extension and retraction movements.

[0045] Reference Figures 4-6In some embodiments of the present application, the guiding moving part 1 comprises a mounting plate 12, a guide rail 13 arranged on the mounting plate 12, and a sliding block 14 in sliding cooperation with the guide rail 13. The guide rail 13 extends horizontally along the preset straight motion track 11, and the sliding block 14 realizes high-precision linear reciprocating motion along the guide rail 13. Since the center line of the guide rail 13 is preferably coincident with or parallel to the rotation axis X of the manipulator body 6, the straight motion track 11 can serve as a symmetrical reference for the two arms during calibration. The sliding block 14 can realize high-precision linear reciprocating motion on the guide rail 13, and the support 2 is rigidly fixed to the sliding block 14. The two manipulator arms are synchronously extended and retracted by the linear reference provided by the guide rail 13-sliding block 14 assembly.

[0046] In some other embodiments of the present application, the guiding moving part 1 can be a linear guide mechanism driven by a hydraulic cylinder. The hydraulic cylinder comprises a rigid piston rod fixedly connected with the sliding block 14. The rigid piston rod is precisely assembled in a closed hydraulic cylinder barrel. The inflow and outflow of hydraulic oil are controlled by a servo valve to drive the piston rod to realize smooth reciprocating motion with high thrust along the preset straight motion track 11. The surface of the piston rod is hardened and ground, and tightly cooperates with the wear-resistant sealing ring in the cylinder barrel to ensure that it can still maintain extremely high straightness and sealing performance without crawling phenomenon even under long-term high-frequency operation, and is particularly suitable for scenes with extremely high requirements for motion stability in wafer handling process. The entire hydraulic drive unit has compact structure and can be directly rigidly connected with the manipulator body or the support frame through the flange mounting surface on the cylinder barrel without additional mounting plate structure. The actual position of the piston rod is fed back by a high-resolution grating ruler, and the system can realize closed-loop control to ensure the synchronization and trajectory consistency of the dual-arm manipulator during extension and retraction motion.

[0047] Referring to Figure 7 and Figure 8 In some embodiments, the support 2 comprises a support seat 21 and a rotation cooperation part 22 arranged on the support seat 21. The support seat 21 is provided with a through mounting hole 215 in the vertical direction, and the rotation cooperation part 22 is mounted in the through mounting hole 215. Part of the floating connecting part 3 is located in the through mounting hole 215 and is rotatably connected with the rotation cooperation part 22. The support seat 21 comprises a fixed part 211, and a first supporting part 212 and a second supporting part 213 integrally formed and symmetrically arranged on both sides of the fixed part 211. Each supporting part is a cylindrical cavity structure and corresponds to the through mounting hole 215. The first supporting part 212 and the second supporting part 213 protrude radially inward along the inner wall to form a ring of retaining rings 214 as the lower end face limiting structure of the bearing outer ring 221 mounted therein, for providing reliable axial positioning to prevent the rotation cooperation part 22 from falling downward under the action of gravity.

[0048] In some embodiments of the present application, the rotating fitting part 22 is a bearing, which comprises an inner ring 222 and an outer ring 221 coaxially arranged and capable of relative rotation. The outer ring 221 of the bearing is mounted in the above-mentioned through mounting hole 215 and fixedly connected with the support 2, and the inner ring 222 of the bearing is in clearance fit with part of the floating connecting piece 3, so that the floating connecting piece 3 can freely rotate around the axis perpendicular to the linear motion track 11 and the axis floats, thereby adapting to the angle deviation and height deviation generated by the two arms when the posture changes during the calibration process. The first support part 212 and the second support part 213 are respectively detachably connected with a first gland 2121 and a second gland 2122, and the two glands are respectively located between the floating connecting piece 3 and the support 2, capable of pressing the upper end face of the outer ring 221 of the bearing, thereby completing the limiting of the upper and lower end faces of the outer ring 221 of the bearing. The first gland 2121 and the second gland 2122 are respectively matched with the upper end face of the cylindrical cavity structure, for pressing and fixing the upper end face of the outer ring 221 of the bearing, so that the outer ring 221 of the bearing forms reliable axial clamping in the cavity and maintains the rotation accuracy.

[0049] With reference to Figure 8 In some embodiments, each floating connecting piece 3 comprises a rotating shaft 31 and a rotating disc 32 coaxially arranged, the rotating disc 32 has a larger diameter than the rotating shaft 31, the rotating shaft 31 is fixedly connected with the rotating disc 32, and the rotating shaft 31 passes through the inner ring 222 of the bearing and realizes controllable floating through the limiting structure. The rotating shaft 31 comprises a telescopic part 311 and a limiting part 312 coaxially arranged, the diameter of the telescopic part 311 is smaller than that of the limiting part 312, the limiting part 312 is located between the rotating disc 32 and the telescopic part 311, the projection diameter of the limiting part 312 along the vertical direction is greater than the inner diameter of the inner ring 222 of the bearing, and through the cooperation of the limiting part 312 and the inner ring 222 of the bearing, the rotating disc 32 can realize axial adaptive floating during device operation, so that the two floating connecting pieces 3 can automatically compensate for the differences in height, thickness or combined installation errors of the two arm end joint 4 structures, thereby improving the compatibility of the device with different robot structures. In addition, since the rotating disc 32 is used for detachable rigid connection with the end joint 4 of the two arms of the robot, a plurality of positioning holes 321 and positioning pins 322 matched with the positioning holes 321 are arranged on the rotating disc 32 to realize the preliminary positioning of the rotating disc 32 and the end joint 4 of the robot arm, and finally a screw 323 is used to fix the rotating disc 32 on the arm, so that the first arm 7 and the second arm 8 are rigidly connected to the floating connecting piece 3 during the calibration process.

[0050] With reference to Figure 6 and Figure 9In some embodiments of the present application, the fixing portion 211 of the support 2 is used to connect with the sliding block 14, and a plurality of spaced waist-shaped holes 2112 are arranged on the upper surface of the fixing portion 211 along the length direction. The position adjusting member 5 is connected with the support 2 through the waist-shaped holes 2112, and includes a fastening bolt 51 and a fastening stud 52. The fastening stud 52 is installed in an adjusting hole 2113 on the support 2, and the adjusting hole 2113 is in communication with a guide groove 2111. By adjusting the fastening stud 52, the installation position of the support 2 on the guide moving member 1 can be finely adjusted. The fixing portion 211 is provided with the guide groove 2111 on the side away from the guide moving member 1 along the direction parallel to the preset straight line motion track 11, and a corresponding convex portion of the sliding block 14 is embedded in the guide groove 2111, so as to prevent the support 2 from being laterally deviated during the straight line movement, and ensure that the support 2 always moves along the track consistent with the guide rail 13 during the whole calibration movement.

[0051] Specifically, the fixing portion 211 is detachably installed on the upper surface of the sliding block 14 through the fastening bolt 51. The fastening bolt 51 passes through the waist-shaped holes 2112 in sequence and is threadedly connected with the screw holes previously provided on the upper surface of the sliding block 14. Since the waist-shaped holes 2112 have a movable allowance within a limited range along the length direction, the fixing portion 211 can be finely adjusted in position relative to the sliding block 14 within the length range of the waist-shaped holes 2112 in the state that the fastening bolt 51 is not completely locked, so as to realize the fine adjustment of the lateral position of the fixing portion 211, and gradually approach the design reference value of the distance between the two turntables 32 provided on the fixing portion 211 relative to the center line of the guide rail 13.

[0052] After the positioning of the fastening bolt 51 is completed, the fastening stud 52 is further provided to cooperate with the adjusting hole 2113, and the adjusting hole 2113 is perpendicular to the screw hole. By driving the fastening stud 52 to rotate and press against the fastening bolt 51, the connection between the fixing portion 211 and the sliding block 14 is further reinforced. By using the coarse adjustment of the fastening bolt 51 and the fine adjustment of the fastening stud 52 in cooperation, the centers of the two turntables 32 can be kept equidistant from the center line of the guide rail 13, so as to ensure the symmetry of the double-arm connecting points and the geometric consistency of the subsequent calibration movement.

[0053] Referring to Figure 10 and Figure 11In order to further ensure the direction accuracy of the guide rail 13 body 6 after assembly, the embodiment is also provided with a guide rail 13 positioning eccentric pin. The eccentric pin is installed on the base or the side wall of the guide rail 13, and the protruding part of the eccentric pin is extruded or gap compensated with the side surface of the guide rail 13 in different amplitudes by rotating the eccentric pin, so as to correct the possible slight deflection of the guide rail 13 relative to the reference mounting surface. The eccentric amount of the eccentric pin can be continuously adjusted in a very small range, so that the center line of the guide rail 13 is accurately aligned with the working reference surface of the slider 14 and the fixed part 211 after adjustment. Through the comprehensive adjustment of the above-mentioned fastening bolts 51, the top wire and the eccentric pin, the relative position relationship of the fixed part 211, the guide rail 13 and the related moving parts can finally meet the requirements of the double-arm symmetry and the movement alignment required by the dynamic calibration without additional complex equipment.

[0054] Working principle: in some other embodiments of the present application, when the dynamic calibration device is used with the manipulator, first, the joint angle positioning screws 323 of the first arm 7 and the second arm 8 are loosened, only the pre-tightening force is retained, and the first shoulder, the first elbow, the first wrist and the second shoulder, the second elbow and the second wrist are allowed to rotate steplessly within a range of ±5° under the condition of maintaining the pre-tightening force. Then the turntable 32 of the first floating connecting piece 3 is detachably rigidly connected with the wrist joint of the first arm 7 through the positioning pin 322 and the bolt; similarly, the turntable 32 of the second floating connecting piece 3 is connected with the wrist joint of the second arm 8. At the same time, the distance between the two wrist joint axes relative to the center line of the slider 14 is ensured to be equal, so that the two arms obtain symmetrical initial conditions under the linear traction in the calibration process.

[0055] When the slider 14 moves along the preset linear motion track 11 under the drive of the guide rail 13, the support 2 carries the two floating connecting pieces 3 to move synchronously along the linear track. Since each floating connecting piece 3 can freely rotate around the axis perpendicular to the linear track and can produce adaptive floating in the direction of the axis, the two arms will automatically compensate for their postures in the process of being pulled out or retracted, so that the large arm, the forearm and the end effector produce the actual required angular fine adjustment around the shoulder, elbow and wrist axes. This passive traction mode based on the linear track can release the accumulated gap at the joint of the arm during multiple reciprocating traction, so that the two arms form consistent motion tracks during the “extension” and “retraction” processes and make the tracks keep mirror symmetry about the center line of the guide rail 13. After multiple reciprocating traction, when the two arms reach track consistency at different positions, that is, the extension and retraction paths coincide, the operator relocks the positioning screws 323 of the joints, and the above-mentioned stepless adjusted postures can be rigidly fixed. Then the connection between the turntable 32 and the arm is released and the whole dynamic calibration device is removed, and the manipulator thus completes the dynamic calibration of the double-arm track.

[0056] In a second aspect, a dynamic calibration method for a dual-arm robot is provided, which utilizes the above-mentioned dual-arm robot dynamic calibration device based on a preset trajectory, and comprises the following steps:

[0057] Loosen the fasteners of each joint of the robot arm, so that each joint has a movement allowance within a predetermined angle range;

[0058] Drive the support 2 to move along the straight movement trajectory 11, and synchronously stretch or contract the two arms through the two floating connectors 3, in the process, each joint is adaptively adjusted based on the rotation and floating of the floating connector 3 to release the mechanical clearance and calibrate the movement trajectory;

[0059] Lock the fasteners of each joint to fix the calibrated posture;

[0060] Release the rigid connection between the floating connector 3 and the arm.

[0061] By the above method steps, the dual arms can respond to the posture adjustment requirement of the floating connector 3 in the movement process by giving each joint a movement allowance before calibration, thereby providing a degree of freedom basis for subsequent error release and structure reconstruction. Subsequently, by driving the support 2 to move along the preset straight trajectory, the dual arms are forced to stretch or contract along a completely consistent geometric trajectory under the synchronous rigid traction of the two floating connectors 3, so that the joints are automatically adjusted to the most stable and geometrically symmetrical position according to the actual stress and posture deviation in the dynamic process. In the whole traction process, each joint completes the continuous release and automatic compensation of manufacturing errors, assembly errors, structural stress and fitting clearance by means of the rotation and floating degrees of freedom of the floating connector 3, thereby realizing the "dynamic self-alignment" process. Unlike the traditional passive consistency control which relies on inherent structural accuracy, the present method adopts a dynamic calibration mode combining external reference driving and internal joint adaptive adjustment, so that the dual arms can complete error dissipation and trajectory reconstruction in the movement. Finally, after the calibrated posture is locked, the dual arms obtain a new posture strictly consistent with the preset trajectory, and the movement consistency can be maintained for a long time in the subsequent operation.

[0062] Although the embodiments of the present application have been described in detail above, it is obvious to those skilled in the art that various modifications and changes can be made to the embodiments. However, it should be understood that such modifications and changes all fall within the scope and spirit of the present application. Moreover, the present application described herein can have other embodiments, and can be implemented or realized in various ways.

Claims

1. A preset trajectory-based dual-arm robot dynamic calibration device, applied to a robot, the robot comprising a body (6) and a first arm (7) and a second arm (8) which are mirror images of each other and can be independently extended or retracted, the first arm (7) comprising a first upper arm (71), a first forearm (72) and a first end effector (73), and sequentially having a first shoulder axis SX1, a first elbow axis EX1 and a first wrist joint axis WX1, characterized in that, The application relates to a robot arm, which comprises the following components: a guiding moving part (1) for providing and restricting a preset straight motion track (11); a supporting part (2) connected with the guiding moving part (1) and capable of moving along the straight motion track (11) under control; two symmetrically arranged floating connecting parts (3) installed on the supporting part (2), the floating connecting parts (3) being located on both sides of the straight motion track (11) and being detachably rigidly connected with the end joints (4) of first arms (7) and second arms (8) respectively; wherein each of the floating connecting parts (3) is capable of rotating around an axis perpendicular to the straight motion track (11) and is capable of adaptive floating along the direction of the axis; when the supporting part (2) moves along the straight motion track (11) under control, the two floating connecting parts (3) can synchronously stretch or contract the first arms (7) and the second arms (8) along the straight motion track (11) through adaptive floating and adaptive rotation; before calibration, the fasteners of the joints of the robot arm are loosened so that the joints have a movement allowance in a preset angle range; the supporting part (2) is driven to move along the straight motion track (11), and the first arms (7) and the second arms (8) are synchronously stretched or contracted through the two floating connecting parts (3); in this process, the joints are adaptively adjusted based on the rotation and floating of the floating connecting parts (3) to release mechanical clearance and calibrate the motion track; after calibration, the fasteners of the joints are locked to fix the calibrated posture; the rigid connection between the floating connecting parts (3) and the first arms (7) and the second arms (8) is released. 2.The preset trajectory based dual-arm robot dynamic calibration device according to claim 1, wherein, The guiding moving part (1) comprises a mounting plate (12), a guide rail (13) arranged on the mounting plate (12) and a sliding block (14) in sliding fit with the guide rail (13), the sliding block (14) is fixedly connected with the supporting part (2), and the guide rail (13) extends horizontally along the straight motion track (11). 3.The preset trajectory based dual-arm robot dynamic calibration device according to claim 2, wherein, The supporting part (2) comprises a supporting seat (21) and a rotating fit part (22), the supporting seat (21) is provided with a through mounting hole (215) in the vertical direction, the rotating fit part (22) is installed in the through mounting hole (215), and part of the floating connecting part (3) is located in the through mounting hole (215) and rotatably connected with the rotating fit part (22). 4.The preset trajectory based dual-arm robot dynamic calibration device according to claim 3, wherein, The rotating fit part (22) is a bearing, the bearing comprises an inner ring (222) and an outer ring (221) which are coaxially arranged and can rotate relative to each other, the outer ring (221) of the bearing is fixedly connected with the supporting part (2), and the inner ring (222) of the bearing is in clearance fit with the floating connecting part (3). 5.The preset trajectory based dual-arm robot dynamic calibration device according to claim 4, wherein, The floating connecting part (3) comprises a rotating shaft (31) and a rotating disc (32) which are coaxially arranged, the rotating disc (32) is larger in diameter than the rotating shaft (31), the rotating shaft (31) is fixedly connected with the rotating disc (32), and the rotating shaft (31) penetrates through the inner ring (222) of the bearing. 6.The preset trajectory based dual-arm robot dynamic calibration device according to claim 5, wherein, The rotating shaft (31) comprises a telescopic part (311) and a limiting part (312) arranged coaxially, the diameter of the telescopic part (311) is smaller than that of the limiting part (312), the limiting part (312) is located between the rotating disc (32) and the telescopic part (311), and the diameter of the projection of the limiting part (312) along the vertical direction is greater than the inner diameter of the inner ring (222). 7.The preset trajectory based dual-arm robot dynamic calibration device according to claim 4, wherein, The support base (21) comprises a fixed part (211), and a first supporting part (212) and a second supporting part (213) integrally formed and symmetrically arranged on both sides of the fixed part (211), the through mounting holes (215) are located on the first supporting part (212) and the second supporting part (213) respectively, the first supporting part (212) and the second supporting part (213) radially protrude inward along the hole inner wall of the through mounting hole (215) to form a ring-shaped stop ring (214), and the stop ring (214) abuts against one end face of the outer ring (221) of the bearing. 8.The preset trajectory based dual-arm robot dynamic calibration device according to claim 7, wherein, The fixed part (211) is provided with a guide groove (2111) on the side away from the guide moving part (1) and parallel to the linear motion track (11), and the sliding block (14) is embedded in the guide groove (2111). 9.The preset trajectory based dual-arm robot dynamic calibration device of claim 8, wherein, The position adjusting part (5) is arranged between the supporting part (2) and the guide moving part (1), and is used for fine adjustment of the installation position of the supporting part (2) on the guide moving part (1). 10.The preset trajectory based dual-arm robot dynamic calibration device according to claim 9, wherein, A plurality of spaced waist-shaped holes (2112) are arranged vertically on the supporting part (2) and extend along the length direction of the supporting part (2), the position adjusting part (5) comprises a fastening bolt (51) and a fastening top wire (52), the fastening bolt (51) is connected with the supporting part (2) through the waist-shaped hole (2112), and the supporting part (2) is provided with an adjusting hole (2113) which is in communication with the guide groove (2111), and the fastening top wire (52) is in threaded connection with the adjusting hole (2113). 11.The preset trajectory based dual-arm robot dynamic calibration device of claim 7, wherein, The first supporting part (212) is detachably connected with a first gland (2121), the second supporting part (213) is detachably connected with a second gland (2122), and the first gland (2121) and the second gland (2122) are located between the floating connecting part (3) and the supporting part (2) and are used for fixing the outer ring (221) of the bearing.

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