A distributed control system supporting shoulder-wrist interchangeable movable robotic arm

Abstract

A distributed control system supporting a movable manipulator with interchangeable shoulders and wrists, comprising: a manipulator operating console, a whole arm controller, a joint controller, an end controller and an Ethernet switch; the manipulator operating console converts human operations into manipulator arm motion control commands, and sends them to the whole arm controller; the whole arm controller receives the operation commands generated by the operating console, generates motion control instructions, and sends them to the joint controller or the end controller; the joint controller receives the operation commands given by the whole arm controller, and controls the corresponding joint motors to operate to a desired angle through a servo control strategy; the end controller controls the end effectors on both sides of the manipulator respectively, receives the motion control commands of the whole arm controller, and controls the motors to complete the end-related motion control; each end effector is installed with a camera and a force sensor; the Ethernet switch collects the video images collected by the camera, and carries out multi-channel image information fusion and processing, and transmits them to the cabin for monitoring.

Description

Technical Field

[0001] The present invention belongs to the field of robot technology, and relates to a distributed control system of a crawling mobile mechanical arm with interchangeable shoulders and wrists, which is used for a symmetrically structured mechanical arm that can complete multi-degree-of-freedom control and communication of the entire arm when the shoulders and wrists are interchangeable. Background Art

[0002] Generally speaking, for a serial robot arm, one end is usually fixed with a base and the other end is equipped with an end effector. The fixed end is used to connect to the external power supply and communication, and the free end is used for motion operation.

[0003] In the prior art, the above-mentioned serial manipulators all place the manipulator controller at the fixed end, and the arm body is an actuator including joints and end effectors. However, for manipulators applied on the surface of spacecraft, it is necessary to cover the entire spacecraft surface by "crawling" the manipulator head and tail to cover the operating space. Therefore, an adaptive control system that adapts to the application characteristics and scenarios is needed, which is crucial for the expanded application of space manipulators. Summary of the invention

[0004] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art and provide a distributed control system for a crawling mobile robotic arm with interchangeable shoulders and wrists, which solves the problems of symmetrical distributed control of the robotic arm and power supply and communication with interchangeable head and tail, and is of great significance for effectively expanding the working space of the robotic arm under the condition of limited robotic arm length.

[0005] The technical solution of the present invention is: a distributed control system supporting a movable mechanical arm with shoulder-wrist interchangeability, comprising: a mechanical arm operating table, a whole arm controller, a joint controller, an end controller and an Ethernet switch;

[0006] The robot arm operation console provides a human-machine interface for robot arm operation, converts human operations into robot arm motion control commands, and sends them to the whole arm controller;

[0007] The whole arm controller receives the operation command generated by the operation console, calls the path planning algorithm, generates motion control instructions, and sends them to the joint controller or the end controller;

[0008] The joint controller receives the operation command given by the whole arm controller, controls the corresponding joint motor to run to the desired angle through the servo control strategy, and ensures the joint movement accuracy;

[0009] The end controllers are distributed at both ends of the robotic arm, controlling the end effectors on both sides of the robotic arm respectively, receiving motion control commands from the whole arm controller, and controlling the motors to complete end-related motion control; each end effector is equipped with a camera and a force sensor;

[0010] The Ethernet switch collects the video images collected by the camera, fuses and processes the multi-channel image information, and transmits it to the cabin for monitoring.

[0011] The joint controllers include a shoulder swivel joint controller, a shoulder yaw joint controller, a shoulder pitch joint controller, an elbow pitch joint controller, a wrist pitch joint controller, a wrist yaw joint controller, and a wrist swivel joint controller.

[0012] When the whole arm control uses a camera, the whole arm controller receives the posture measurement data of the hand-eye camera, generates whole arm motion control instructions through the visual closed-loop autonomous control algorithm, and controls the joint motors through the joint controller to complete related actions; when the whole arm control uses a force sensor, the whole arm controller receives the force sensing measurement data generated by the end controller, generates whole arm force-position mixed motion control instructions through the force control algorithm, and controls the joint motors through the joint controller to complete related actions.

[0013] The camera receives control commands forwarded by the whole arm controller, including video acquisition and posture solution parameter setting commands, and obtains motion monitoring images; calculates target posture data and transmits it back to the whole arm controller; the camera includes a hand-eye camera and an elbow camera.

[0014] The installation position of the robot arm serves as a working platform, providing mechanical, power distribution and information interfaces for the robot arm; the first-level control of the robot arm's power distribution is designed at the working area of ​​the robot arm's operating table; the power distribution unit on the working platform provides the robot arm with two power supply bus bars and one command bus bar, and each bus bar is independently controlled in the power distribution unit to realize the first-level control of power distribution; the robot arm operating table is independently controlled by the power distribution unit.

[0015] The second-level control of the robot arm power distribution is designed at the end effector. The power supply and command bus output by the work platform distribution unit are input to the end power supply module inside the end effector, and the end power supply module distributes power to one of the power supply buses. Control relays are designed for the positive lines of the two power supply buses and one command bus in the end power supply module, and the on and off are controlled by the end controller.

[0016] The third-level control of the robot arm power distribution is designed in each joint controller, end effector, Ethernet switch, hand-eye camera, elbow camera and whole-arm controller of the robot arm; the end power supply module provides a power supply path for the end controller and hand-eye camera; a termination module is installed in the joint to split the power of one power bus and send it to the motor power module in the joint, and then transmit it to the next joint; the joint controller controls the power on and off of the power module by controlling the enable end of the motor power module; a termination module is installed in the whole-arm controller to split the power of another power bus and send it to the electronic components inside the whole-arm controller, the Ethernet switch and elbow camera installed on the external shell of the whole-arm controller, and then transmit it to the next joint.

[0017] On-off control switches are designed inside the joint controller, camera, and Ethernet switch. The work platform power distribution unit directly controls the power on and off of the end controller and the whole arm controller. The whole arm controller controls the power on and off of each joint controller, Ethernet switch, and elbow camera. The end effector controls the power on and off of the hand-eye camera.

[0018] The two power supply buses are input through the floating electrical connector on the end effector assembly, and the two power supply paths are isolated from each other to meet the isolation impedance requirements; one power supply bus supplies power to all controllers and cameras; and the other power supply bus supplies power to all joint motors.

[0019] Each power supply bus adopts multi-point and multi-line transmission, the positive and negative contacts are isolated by area, the minimum positive and negative safety distances are maintained to meet the use requirements, and the insulation and withstand voltage of the power transmission electrical connector meet the use requirements.

[0020] The advantages of the present invention compared with the prior art are:

[0021] Through the design of symmetrical distributed control systems, it is possible to expand the application scenarios of the robotic arm on the basis of the symmetrical structure of the mechanical body and improve the efficiency of the robotic arm without having to arrange the control system separately according to the head-to-tail interchangeability characteristics. The end controller and the whole arm controller serve as the control center connected to the outside world. Through a set of power supply and bus systems, the electrical interface connection relationship is switched on different connection bases, so that the robotic arm has the ability to move and crawl, improve the working space and reliability of the robotic arm, and reduce the redundancy of the robotic arm design. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the robotic arm control system architecture;

[0023] Figure 2 Schematic diagram of the information flow of the robotic arm control system. DETAILED DESCRIPTION

[0024] System architecture:

[0025] The physical system of the robotic arm includes an operating console outside the arm body, a whole arm controller inside the arm body, seven joints, two end effectors, an Ethernet switch installed outside the whole arm controller, an elbow camera, and a hand-eye camera installed outside the end effector. Among them, the joints and end effectors are mechatronic products. The joints contain motors, reducers, brakes, motor power modules, terminal modules and housings. The end effectors contain motors, actuators, end supply modules, capture mechanisms, and electrical connectors.

[0026] The robotic arm control system adopts a three-level distributed control architecture consisting of a command and scheduling layer, an entire arm motion planning layer, and a component execution control layer.

[0027] First layer: command and scheduling

[0028] Specific execution equipment: Robotic arm operating table

[0029] The basic function is to provide a human-machine interface for robot arm operation, convert human operations into robot arm motion control commands, and send them to the entire arm controller.

[0030] Second layer: whole arm motion planning

[0031] Specific execution equipment: whole arm controller

[0032] Basic functions:

[0033] (1) Receive the operation command generated by the console, call the corresponding path planning algorithm, generate motion control instructions, and send them to the joint controller or end controller;

[0034] (2) When a hand-eye camera is installed on the end effector, it receives the posture measurement data of the hand-eye camera, calls the visual closed-loop autonomous control algorithm, and generates motion control instructions;

[0035] (3) When a force sensor is installed on the end effector, it receives the force sensing measurement data generated by the end controller, calls relevant algorithms such as force control, and generates motion control instructions.

[0036] Layer 3: Component Execution Control

[0037] Specific execution equipment: joint controller, end controller, hand-eye camera controller, elbow camera controller, Ethernet switch.

[0038] Basic control functions:

[0039] (1) Joint controller: receives the operation command from the whole arm controller and ensures the joint motion accuracy through servo control strategy;

[0040] (2) End controller: receives motion control commands from the whole arm controller and controls the motor to complete end-related motion control;

[0041] (3) Hand-eye camera and elbow camera: receive the video acquisition and posture calculation parameter setting commands forwarded by the whole arm controller to obtain motion monitoring images; calculate the target posture data and transmit it to the whole arm controller for visual autonomous control;

[0042] (4) Ethernet switch: collects video images from wrist cameras and elbow cameras and transmits them to the cabin for monitoring.

[0043] Information system:

[0044] The robot arm is installed at the working position, and the robot arm operating table is installed next to the working position. The information interaction transmission mode of the distributed control system is as follows:

[0045] (1) The video information of the robot arm camera is transmitted via Ethernet. The Ethernet cable is connected to the switch, and the main and backup videos are synthesized and transmitted to the operation console for processing and display through the base connectors connected to each of them;

[0046] (2) The robot arm uses a dedicated bus such as 1553B and CAN. The robot arm console acts as a BC to exchange data with the robot arm end effector controller connected to the base connector on this bus;

[0047] (3) In the robot arm bus, the whole arm controller acts as the BC to carry out internal data transmission with the joint controller, end effector controller, Ethernet switch and camera.

[0048] The motion commands of the robotic arm are generated by the robotic arm operating console, forwarded to the whole arm controller through the data bus, and then sent by the whole arm controller to terminal devices such as joint controllers and end controllers for execution.

[0049] During the operation, the whole arm controller is responsible for collecting the measurement information and status data of each part of the robot body, and then forwarding it to the robot operation console, which then sends it to the instrument display system for display. Video images assist operators in operating the robot arm.

[0050] Power distribution design:

[0051] In terms of power supply and distribution architecture, the distributed control system adopts a split power supply system to provide two power supply buses for the robotic arm. The power distribution is divided as follows:

[0052] a. The first bus provides power for all controllers and cameras;

[0053] b. The second bus provides power to all joint motors.

[0054] Both of the above power supply paths adopt an isolation design. The two busbars are input through the floating electrical connector on the end effector assembly, and the two power supply paths are isolated from each other to meet the isolation impedance requirements. According to the actual application power requirements, each busbar can adopt multi-point multi-line transmission, and the positive and negative contacts are isolated by area. The minimum positive and negative safety distance is maintained to meet the use requirements, and the insulation withstand voltage of the power transmission electrical connector meets the use requirements.

[0055] The robot body adopts a distributed power distribution design in series and a three-level power distribution control system. For details, see Figure 2 :

[0056] Level 1: Design the first-level control of the robot arm power distribution on the robot arm operating platform (at the work area). The work platform power distribution unit provides two power supply buses and one command bus for the robot arm. Each bus is on and off controlled in the power distribution unit to achieve the first-level control of power distribution. The robot arm operating table is controlled separately by the power distribution unit.

[0057] Level 2: Design the second-level control of the robot arm power distribution at the end effector of the robot arm. The power supply and command bus output by the work platform power distribution unit are input to the terminal power supply module, and the terminal power supply module distributes the first 100V bus; control relays are designed in the terminal power supply module for the positive line of the 2-way bus and the command bus, and the terminal controller controls the on and off.

[0058] Level 3: The third level control of the robot arm power distribution is designed in each joint controller, end effector, Ethernet switch, hand-eye camera and whole arm controller of the robot arm. The end power supply module provides a power supply path for the end controller and the hand-eye camera; the terminal module is installed in the joint, and the power supply bus is divided and sent to the motor power module in the joint, and then transmitted to the next joint; the joint controller controls the power on and off of the power module by controlling the enable end of the motor power module; the terminal module is installed in the whole arm controller, and the bus is divided and sent to the whole arm controller electronic components, elbow switch, and transmitted to the next joint, etc. The on-off control switch is designed inside each product. The work platform power distribution unit directly controls the power on and off of the end controller and the whole arm controller. The whole arm controller controls the power on and off of the 7 joint controllers and the Ethernet switch, and the end effector controls the power on and off of the hand-eye camera.

[0059] Parts of the present invention that are not described in detail belong to common knowledge among those skilled in the art.

Claims

1. A distributed control system supporting a movable robotic arm with shoulder-wrist interchangeability, characterized in that include: Robotic arm operating table, whole arm controller, joint controller, end controller and Ethernet switch; The robot arm operation console provides a human-machine interface for robot arm operation, converts human operations into robot arm motion control commands, and sends them to the whole arm controller; The whole arm controller receives the operation command generated by the operation console, calls the path planning algorithm, generates motion control instructions, and sends them to the joint controller or the end controller; The joint controller receives the operation command given by the whole arm controller, controls the corresponding joint motor to run to the desired angle through the servo control strategy, and ensures the joint movement accuracy; The end controllers are distributed at both ends of the robotic arm, controlling the end effectors on both sides of the robotic arm respectively, receiving motion control commands from the whole arm controller, and controlling the motors to complete end-related motion control; each end effector is equipped with a camera and a force sensor; The Ethernet switch collects the video images collected by the camera, carries out multi-channel image information fusion and processing, and transmits them to the cabin for monitoring; The installation position of the manipulator serves as a working platform, providing mechanical, power distribution, and information interfaces for the manipulator; the first-level control of the manipulator's power distribution is designed at the working area of ​​the manipulator's operating table; the power distribution unit on the working platform provides the manipulator with two power supply buses and one command bus, and each bus is individually controlled in the power distribution unit to achieve the first-level control of power distribution; the manipulator's operating table is individually controlled by the power distribution unit; The second-level control of the power distribution of the manipulator is designed at the end effector. The power supply and command bus output by the power distribution unit of the working platform are input to the end power supply module inside the end effector, and the end power supply module distributes power to one of the power supply buses; the positive lines of the two power supply buses and one command bus are designed with control relays in the end power supply module, and the end controller controls the on-off; The third-level control of the robot arm power distribution is designed in each joint controller, end effector, Ethernet switch, hand-eye camera, elbow camera and whole-arm controller of the robot arm; the end power supply module provides a power supply path for the end controller and hand-eye camera; a termination module is installed in the joint to split the power of one power bus and send it to the motor power module in the joint, and then transmit it to the next joint; the joint controller controls the power on and off of the power module by controlling the enable end of the motor power module; a termination module is installed in the whole-arm controller to split the power of another power bus and send it to the electronic components inside the whole-arm controller, the Ethernet switch and elbow camera installed on the external shell of the whole-arm controller, and then transmit it to the next joint.

2. A distributed control system for a movable manipulator supporting shoulder-wrist interchangeability according to claim 1, characterized in that: The joint controllers include a shoulder swivel joint controller, a shoulder yaw joint controller, a shoulder pitch joint controller, an elbow pitch joint controller, a wrist pitch joint controller, a wrist yaw joint controller, and a wrist swivel joint controller.

3. A distributed control system for a movable manipulator supporting shoulder-wrist interchangeability according to claim 1, characterized in that: When the whole arm control uses a camera, the whole arm controller receives the posture measurement data of the hand-eye camera, generates whole arm motion control instructions through the visual closed-loop autonomous control algorithm, and controls the joint motors through the joint controller to complete related actions; when the whole arm control uses a force sensor, the whole arm controller receives the force sensing measurement data generated by the end controller, generates whole arm force-position mixed motion control instructions through the force control algorithm, and controls the joint motors through the joint controller to complete related actions.

4. A distributed control system for a movable manipulator supporting shoulder-wrist interchangeability according to claim 1, characterized in that: The camera receives control commands forwarded by the whole arm controller, including video acquisition and posture solution parameter setting commands, and obtains motion monitoring images; calculates target posture data and transmits it back to the whole arm controller; the camera includes a hand-eye camera and an elbow camera.

5. The distributed control system for supporting shoulder-wrist interchangeable movable robotic arms according to claim 1, characterized in that: On-off control switches are designed inside the joint controller, camera, and Ethernet switch. The work platform power distribution unit directly controls the power on and off of the end controller and the whole arm controller. The whole arm controller controls the power on and off of each joint controller, Ethernet switch, and elbow camera. The end effector controls the power on and off of the hand-eye camera.

6. A distributed control system for a movable manipulator supporting shoulder-wrist interchangeability according to claim 1, characterized in that: The two power supply buses are input through the floating electrical connector on the end effector assembly, and the two power supply paths are isolated from each other to meet the isolation impedance requirements; one power supply bus supplies power to all controllers and cameras; and the other power supply bus supplies power to all joint motors.

7. A distributed control system for a movable manipulator supporting shoulder-wrist interchangeability according to claim 1, characterized in that: Each power supply bus adopts multi-point and multi-line transmission, the positive and negative contacts are isolated by area, the minimum positive and negative safety distances are maintained to meet the use requirements, and the insulation and withstand voltage of the power transmission electrical connector meet the use requirements.

Images