A rigid-flexible dual-arm collaborative robot

Abstract

The present invention discloses a rigid-flexible dual-arm collaborative robot, comprising a robot controller and a visual measurement device, a rigid serial multi-degree-of-freedom robotic arm, and a flexible serial-parallel multi-degree-of-freedom robotic arm, all connected in sequence. The rigid serial multi-degree-of-freedom robotic arm is equipped with an end-of-arm fixture capable of gripping a target object within the rigid serial multi-degree-of-freedom robotic arm's workspace. After grasping the target object, the robotic arm performs a secondary collaborative operation on or near the target object, expanding the capabilities of conventional multi-degree-of-freedom robotic arms and enabling flexible collaborative operations with large payloads and a wide range of capabilities, as well as in small spaces.

Description

Technical Field

[0001] The present invention relates to the field of robots, and in particular to a rigid-flexible dual-arm collaborative robot. Background Art

[0002] Entering the 21st century, industrial robots have become a significant industry. Currently, industrial robotic arms are mostly used in fixed environments, with fewer applications targeting moving objects. This limits their application scenarios and functionality.

[0003] In the existing technology, such as patent CN201610065290.7, there is an industrial robot arm, which includes a rotating base, an upper arm, a lower arm and a wrist. Using this robot arm to perform secondary operations on the target object requires the coordination of both arms, which limits its scope of use and needs to be improved and enhanced. Summary of the Invention

[0004] Purpose of the invention: In view of the shortcomings and defects of the existing technology, the present invention provides a rigid-flexible dual-arm collaborative robot, which enables the robot arm to perform secondary collaborative operations on or near the surface of the target object after grasping the target object. It can expand the functions of general multi-freedom robot arms and realize large-load, large-range working and flexible collaborative operations of the collaborative robot arm in a small space.

[0005] Technical Solution: The present invention provides a rigid-flexible dual-arm collaborative robot, characterized by comprising a robot controller and a visual measurement device, a rigid serial multi-degree-of-freedom robotic arm, and a flexible serial-parallel multi-degree-of-freedom robotic arm connected in sequence, wherein the rigid serial multi-degree-of-freedom robotic arm is provided with an end fixture of the robotic arm at the end thereof, capable of gripping a target object within the workspace of the rigid serial multi-degree-of-freedom robotic arm;

[0006] The rigid serial multi-degree-of-freedom robotic arm includes a slewing base, an upper arm, a lower arm, and a wrist connected in sequence. The slewing base is connected to a robot controller and a visual measurement device, and the wrist is connected to a fixture at the end of the robotic arm. The rigid serial multi-degree-of-freedom robotic arm can reach any point position within its workspace and can achieve large loads and a wide range of motion.

[0007] The flexible serial-parallel multi-degree-of-freedom manipulator is located on the sixth axis of the wrist, and its base coordinates are fixed coordinate transformations relative to the tool coordinates of the multi-degree-of-freedom manipulator. It is composed of several multi-degree-of-freedom parallel mechanisms connected in series and driven by a driving device at its bottom, and a mechanical gripper is provided at its end; the flexible serial-parallel multi-degree-of-freedom manipulator is used to adjust the telescopic combination rods of the flexible serial-parallel multi-freedom radical manipulator after the rigid serial multi-freedom manipulator steps to grasp the target object, and the mechanical gripper is fixed at the end of the flexible serial-parallel multi-degree-of-freedom manipulator, and can perform fine operations on the surface of the target object. The mechanical gripper is used for the flexible serial-parallel multi-degree-of-freedom manipulator to perform fine operations of clamping and rotating on its surface after the flexible serial-parallel multi-degree-of-freedom manipulator captures the target object;

[0008] The robot controller and the visual measurement device control the rigid serial multi-degree-of-freedom robotic arm, the flexible serial-parallel multi-degree-of-freedom robotic arm, and the tooling fixture at the end of the robotic arm.

[0009] Among them, the rigid serial multi-degree-of-freedom robotic arm is a four-six degree-of-freedom serial mechanism, and the four-six degree-of-freedom serial mechanism includes four-six branches and four-six drive motors, and each branch is connected by a rotating pair.

[0010] The end fixture of the manipulator arm has two degrees of freedom, and its grasping or adsorption torque is controlled by controlling the magnitude of its current, so as to capture the target object.

[0011] The flexible serial-parallel multi-DOF robotic arm is a serial-parallel mechanical structure, comprising telescopic assembly rods, a ball joint, a mounting chassis, a drive device, and a mechanical gripper. The drive device controls the extension and retraction of each joint in the multi-DOF parallel mechanism, achieving arm extension and gripper position, thus enabling the serial-parallel mechanical structure to have a richer workspace.

[0012] Among them, the three multi-degree-of-freedom parallel mechanisms are connected in series to form a three-degree-of-freedom parallel robot series mechanism.

[0013] Among them, the robot controller and visual measurement device are control systems based on a PLC controller, which internally contains a robot motion controller; the control system includes a 4G / 5G module and a video monitoring module, and remote video monitoring, operation and data transmission of the equipment are realized through the PLC controller, 4G / 5G module and video monitoring module.

[0014] The rigid-flexible dual-arm collaborative robot is characterized by the following working process:

[0015] 1) After receiving the work instruction, the visual measurement system determines the target pose;

[0016] 2) The motion control system calculates the path and moves the end fixture of the robotic arm to the target object;

[0017] 3) The fixture at the end of the robotic arm captures the moving target and provides feedback;

[0018] 4) After the control system receives the signal, the vision and laser systems determine the position of the target object;

[0019] 5) The control system drives the flexible serial-parallel multi-degree-of-freedom robotic arm to move to the target object for collaborative operation;

[0020] 6) After the operation is completed, the rigid and flexible arms help the robot return to its initial position.

[0021] The rigid-flexible dual-arm collaborative robot is characterized by the following working process:

[0022] 1) The rigid-flexible dual-arm collaborative robot receives a working signal, and an external input device transmits the coordinates of the target object relative to the external input device to the rigid serial multi-degree-of-freedom robotic arm. The external input device is a visual measurement device, and the motion controller in the control box uses coordinate transformation to resolve the relative coordinates to obtain the workpiece coordinates of the target object.

[0023] 2) The motion controller determines through analysis that its coordinates meet the workspace requirements of the rigid serial multi-DOF manipulator. The rigid serial multi-DOF manipulator uses the target object as the target point. The PLC control unit sends drive signals to the motors of each joint of the four- to six-DOF manipulator based on the position of the target point relative to the coordinates of the manipulator base, so that the rigid serial multi-DOF manipulator moves within its workspace and moves the tooling fixture at the end of the manipulator to the gripping position.

[0024] 3) After the end fixture of the manipulator reaches the gripping position, the PLC controls the end fixture of the manipulator to grip the target object, so that the relative coordinates between the target object and the tool coordinates of the rigid serial multi-degree-of-freedom manipulator remain unchanged;

[0025] 4) The external input device transmits the relative coordinates between the desired working position on the target object and the tool coordinates of the rigid serial multi-DOF manipulator to the motion controller. The motion controller uses coordinate transformation to resolve the received relative coordinates to obtain the workpiece coordinates of the target object relative to the flexible serial-parallel multi-DOF manipulator.

[0026] 5) The motion controller uses kinematic analysis to take the position of the target object as the target posture. The motion control unit sends drive signals to the joints of each parallel mechanism of the flexible serial-parallel multi-degree-of-freedom robotic arm according to the target posture, so that the flexible serial-parallel multi-degree-of-freedom robotic arm can move and move the end mechanical gripper to the target posture and perform collaborative operations such as tightening, grinding and assembly.

[0027] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: The rigid-flexible collaborative robot of the present invention can expand the functions of general industrial robotic arms. Compared with the operation of a single-arm robotic arm, the present invention can remotely control the flexible mechanical device at the end of the robot after completing the single-arm operation content, thereby being able to perform secondary collaborative operations such as tightening, grinding and assembly on the surface and periphery of the target object, thereby realizing the function of dual-arm collaboration.

[0028] The rigid-flexible collaborative robot of the present invention can be applied to a target object in an irregular motion state, and the object can be captured and its irregular motion can be restricted by a rigid serial multi-degree-of-freedom robotic arm. At this time, the flexible serial-parallel multi-degree-of-freedom robotic arm and the moving object are in a relatively static state, and the target posture of the flexible serial-parallel multi-degree-of-freedom robotic arm is fixed. At this time, the working environment of the flexible serial-parallel multi-degree-of-freedom robotic arm is more stable than the dual-arm collaborative working environment, and is more economical than the dual-arm system. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of the present invention;

[0030] Figure 2 It is a structural block diagram of the present invention;

[0031] Figure 3 Schematic diagram of the structure of the rigid serial multi-degree-of-freedom robotic arm of the present invention;

[0032] Figure 4 Schematic diagram of the structure of the flexible serial-parallel multi-degree-of-freedom robotic arm of the present invention;

[0033] Figure 5 It is a workflow diagram of the present invention;

[0034] Figure 6 Schematic diagram of coordinate transformation relationship of the flexible serial-parallel multi-degree-of-freedom manipulator of the present invention;

[0035] In the figure, 1 is a rigid serial multi-degree-of-freedom robot arm; 2 is a fixture at the end of the robot arm; 3 is a flexible serial-parallel multi-degree-of-freedom robot arm; 4 is a robot controller and a visual measurement device; 11 is a rotary base; 12 is an upper arm; 13 is a lower arm; 14 is a wrist; 31 is a mounting chassis; 32 is a multi-degree-of-freedom parallel mechanism; 33 is a driving device; and 34 is a mechanical gripper. DETAILED DESCRIPTION

[0036] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0037] like Figure 1 、 Figure 3 and Figure 4The present invention provides a rigid-flexible dual-arm collaborative robot, comprising a robot controller and a visual measurement device 4, a rigid serial multi-DOF manipulator 1, and a flexible serial-parallel multi-DOF manipulator 3, connected in sequence. The rigid serial multi-DOF manipulator 1 is provided with a manipulator end fixture 2 at its end. The rigid serial multi-DOF manipulator 1 comprises a slewing base 11, an upper arm 12, a lower arm 13, and a wrist 14, connected in sequence. The slewing base 11 is connected to the robot controller and the visual measurement device 4, and the wrist 14 is connected to the manipulator end fixture 2. The robot controller and the visual measurement device 4 are placed at the bottom of the rigid serial multi-DOF manipulator 1, and the manipulator end fixture 2 is mounted at the end of the sixth axis of the rigid serial multi-DOF manipulator 1. The flexible serial-parallel multi-DOF manipulator 3 is located on the sixth axis of the wrist 14. Its base coordinates are a fixed coordinate transformation relative to the multi-DOF manipulator tool coordinates. It is composed of a plurality of multi-DOF parallel mechanisms 32 connected in series and driven by a drive device 33 at its bottom. A mechanical gripper 34 is provided at its end. The flexible serial-parallel multi-degree-of-freedom robotic arm 3 is installed on the seventh rod of the robotic arm wrist 14, and is perpendicular to the installation plane of the robotic arm end fixture 2. The flexible serial-parallel multi-degree-of-freedom robotic arm 3 includes a mounting chassis 31, multiple three-degree-of-freedom parallel robot serial mechanisms and a driving device 33.

[0038] The robot controller and visual measurement device 4 control the rigid serial multi-DOF manipulator 1, the flexible serial-parallel multi-DOF manipulator 3, and the manipulator end fixture 2. The rigid serial multi-DOF manipulator 1 is a four-to-six DOF serial mechanism, consisting of four to six branches and four to six drive motors, each linked by a revolute pair. The manipulator end fixture 2 has two degrees of freedom, and its gripping or holding torque is controlled by controlling the current flowing through it. The flexible serial-parallel multi-DOF manipulator 3 is a serial-parallel mechanical structure, comprising telescopic assembly rods, a ball joint, a mounting chassis 31, a drive device 33, and a mechanical gripper 34. The drive device 33 controls the extension and retraction of each joint in the multi-DOF parallel mechanism 32, achieving arm extension and the position of the mechanical gripper 34. The three multi-DOF parallel mechanisms 32 connected in series form a three-DOF parallel robot serial mechanism. The robot controller and visual measurement device 4 is a control system based on a PLC controller, which contains a robot motion controller. The control system includes a 4G / 5G module and a video monitoring module, which realize remote video monitoring, operation and data transmission of the equipment through the PLC controller, 4G / 5G module and video monitoring module.

[0039] When the equipment starts working, the position and posture of the target object are determined by the visual measurement device. The robot controller controls the rigid multi-degree-of-freedom industrial robot arm 1 to move to the working position. The tooling fixture 2 at the end of the robot arm clamps the target object and can move to the installation position within a large stroke range. The flexible device performs trajectory planning based on visual positioning measurement, and flexibly completes collaborative operations such as tightening, grinding and assembly in a limited space within a small stroke range on the target object.

[0040] When the rigid-flexible dual-arm collaborative robot of the present invention is working, it includes the following steps:

[0041] 1) The rigid-flexible dual-arm collaborative robotic arm system receives a working signal to recover a floating object on the water. At this time, the visual system, i.e., the laser ranging device, maps the position of the floating target object as a set of coordinate vector matrices Cn. The motion controller determines a target object coordinate C through a control algorithm. This coordinate C is determined based on the coordinate Q of the visual system. The target object coordinate C is converted into coordinate B through coordinate transformation. At this time, coordinate B is determined based on the coordinate A of the rigid serial multi-degree-of-freedom robotic arm 1.

[0042] 2) After the coordinates of the floating target object are determined, the motion controller performs inverse kinematics calculations and trajectory planning. The PLC sends drive signals to the joints of the four- to six-degree-of-freedom robotic arm, causing the rigid serial multi-degree-of-freedom robotic arm 1 to move within its workspace and move the end fixture 2 to the gripping position.

[0043] 3) After the end fixture 2 of the manipulator reaches the gripping position, the PLC control unit controls the end fixture 2 of the manipulator to grip the target object, so that the relative coordinates between the target object and the tool coordinates of the rigid serial multi-degree-of-freedom manipulator 1 remain unchanged, and feeds back the signal to the robot controller.

[0044] 4) After the robot controller receives the signal that the clamping is completed, the vision system determines the coordinates of the hook position, and the motion controller calculates the coordinates of the hook relative to the flexible serial-parallel multi-degree-of-freedom manipulator 3. The PLC gives the control unit a drive signal to the joints of each parallel mechanism of the flexible serial-parallel multi-degree-of-freedom manipulator 3 according to the target posture, so that the flexible serial-parallel multi-degree-of-freedom manipulator 3 can move and move the end mechanical clamp to the hook posture, and drive the end clamp to clamp the hook. After the clamping is completed, the feedback signal is sent to the robot controller.

[0045] 5) After the robot controller receives the signal that the gripping is completed, the vision system determines the position of the target object's lifting ring, and the motion controller calculates the coordinates of the lifting ring relative to the end hook of the flexible serial-parallel multi-degree-of-freedom manipulator 3. The PLC gives the control unit a driving signal to the joints of each parallel mechanism of the flexible serial-parallel multi-degree-of-freedom manipulator 3 according to the target posture, so that the flexible serial-parallel multi-degree-of-freedom manipulator 3 can move and move the end hook to the lifting ring posture, and drive the flexible serial-parallel multi-degree-of-freedom manipulator 3 to make the hook hook the lifting ring. After completion, the signal is fed back to the robot controller.

[0046] 6) After the control box receives the hook completion signal, the flexible serial-parallel multi-degree-of-freedom robotic arm 3 and the end fixture 2 of the robotic arm are released, and the rigid-flexible dual-arm collaborative robot returns to its initial position and waits for operation instructions.

[0047] At present, the application scenarios of industrial robotic arms at home and abroad are mostly fixed scene environments, and there are few scenarios with moving objects as the operation targets, and their application scenarios and functions are limited.

[0048] In response to this, the present invention develops a serial robotic arm device suitable for working in unstable environments and capable of performing secondary operations on target objects based on actual needs, thereby expanding the functions of general robotic arms.

[0049] In the existing technology, such as patent CN201610065290.7, there is an industrial robot arm, which includes a rotating base, an upper arm, a lower arm and a wrist. Using this robot arm to perform secondary operations on the target object requires the coordination of both arms, which limits its scope of use and needs to be improved and enhanced.

[0050] To address this, the robot controller in this design controls the rigid multi-DOF manipulator (1) to move over a wide range and grasp the target. The flexible serial-parallel multi-DOF manipulator (3) uses visual positioning measurements to perform trajectory planning, flexibly completing collaborative operations such as tightening, grinding, and assembly within a limited range on the target object. This enables the collaborative manipulator to operate with large payloads, over a wide range, and in a flexible and collaborative manner within a small space.

Claims

1. A rigid-flexible dual-arm collaborative robot, characterized by: It comprises a robot controller and a visual measurement device (4), a rigid serial multi-degree-of-freedom robot arm (1) and a flexible serial-parallel multi-degree-of-freedom robot arm (3) connected in sequence, wherein the end of the rigid serial multi-degree-of-freedom robot arm (1) is provided with a robot arm end fixture (2); The rigid serial multi-degree-of-freedom robotic arm (1) comprises a rotary base (11), a large arm (12), a small arm (13) and a wrist (14) connected in sequence, the rotary base (11) being connected to a robot controller and a visual measurement device (4), and the wrist (14) being connected to a tooling fixture (2) at the end of the robotic arm; The flexible serial-parallel multi-degree-of-freedom manipulator (3) is located on the sixth axis of the wrist (14), and its base coordinates are fixed coordinate transformations relative to the tool coordinates of the multi-degree-of-freedom manipulator. It is composed of a plurality of multi-degree-of-freedom parallel mechanisms (32) connected in series and driven by a driving device (33) at its bottom, and a mechanical gripper (34) is provided at its end. The robot controller and the visual measurement device (4) control the rigid serial multi-degree-of-freedom robotic arm (1), the flexible serial-parallel multi-degree-of-freedom robotic arm (3), and the robotic arm end fixture (2); The workflow of the rigid-flexible dual-arm collaborative robot is as follows: 1) The rigid-flexible dual-arm collaborative robot receives a working signal, and an external input device transmits the coordinates of the target object relative to the external input device to the rigid serial multi-degree-of-freedom robot arm (1). The external input device is a visual measurement device, and the motion controller in the control box resolves the relative coordinates to obtain the workpiece coordinates of the target object through coordinate transformation; 2) The motion controller determines through analysis that its coordinates meet the workspace requirements of the rigid serial multi-degree-of-freedom manipulator (1). The rigid serial multi-degree-of-freedom manipulator (1) takes the target object as the target point. The PLC control unit sends a drive signal to the motors of each joint of the four-six-degree-of-freedom manipulator according to the position of the target point relative to the coordinates of the manipulator base, so that the rigid serial multi-degree-of-freedom manipulator (1) moves within its workspace and moves the tooling fixture (2) at the end of the manipulator to a gripping position. 3) After the end fixture (2) of the manipulator reaches the gripping position, the PLC controls the end fixture (2) of the manipulator to grip the target object, so that the relative coordinates between the target object and the tool coordinates of the rigid serial multi-degree-of-freedom manipulator (1) remain unchanged; 4) The external input device transmits the relative coordinates between the desired working position on the target object and the tool coordinates of the rigid serial multi-degree-of-freedom manipulator (1) to the motion controller, and the motion controller resolves the received relative coordinates through coordinate transformation to obtain the workpiece coordinates of the target object relative to the flexible serial-parallel multi-degree-of-freedom manipulator (3); 5) The motion controller uses the position and posture of the target object as the target posture through kinematic analysis. The motion control unit gives driving signals to the joints of the parallel mechanisms of the flexible serial-parallel multi-degree-of-freedom manipulator (3) according to the target posture, so that the flexible serial-parallel multi-degree-of-freedom manipulator (3) can move and move the end mechanical gripper to the target posture and perform collaborative operations such as tightening, grinding and assembly.

2. The rigid-flexible dual-arm collaborative robot according to claim 1, characterized in that: The rigid serial multi-degree-of-freedom manipulator (1) is a four-six degree-of-freedom serial mechanism, which includes four-six branches and four-six drive motors, and each branch is connected by a rotating pair.

3. The rigid-flexible dual-arm collaborative robot according to claim 1, characterized in that: The manipulator end fixture (2) has two degrees of freedom, and its grasping or adsorption torque is controlled by controlling the magnitude of its current.

4. The rigid-flexible dual-arm collaborative robot according to claim 1, characterized in that: The flexible serial-parallel multi-degree-of-freedom robotic arm (3) is a serial-parallel mechanical structure, comprising a telescopic assembly rod, a ball joint, a mounting chassis (31), a driving device (33) and a mechanical gripper (34); the driving device (33) controls the extension and contraction of each joint of the multi-degree-of-freedom parallel mechanism (32) to achieve the extension of the arm span and the state of the mechanical gripper (34).

5. The rigid-flexible dual-arm collaborative robot according to claim 4, characterized in that: The three multi-degree-of-freedom parallel mechanisms (32) are connected in series to form a three-degree-of-freedom parallel robot series mechanism.

6. The rigid-flexible dual-arm collaborative robot according to claim 1, characterized in that: The robot controller and visual measurement device (4) is a control system based on a PLC controller, which internally includes a robot motion controller; the control system includes a 4G / 5G module and a video monitoring module, and remote video monitoring, operation and data transmission of the equipment are realized through the PLC controller, 4G / 5G module and video monitoring module.

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