Design And Research Of Six Degrees Of Freedom Collaborative Robot Control System

With the development of the manufacturing industry toward automation and intelligence,the robot market is getting bigger.Traditional industrial robots belong to heavy equipment,and should be used away from people to avoid robot injury to the operator.Collaborative robots with higher safety can have zero distance contact with people,the man-machine cooperation to complete some complex tasks,so collaborative robots have been gradually more and more widely used.Taking a kind of torque sensor feedback collaborative robot as research object,based on Ether CAT bus technology and Twin CAT3 software platform,and combined with the openness of the coordination control system of the robot and real time demand,the paper put forward a kind of the robot control system with collaboration capabilities that can realize a double feedback between force and position control.The paper mainly contains the following work:(1)The D-H method was used to establish the kinematics model,and the forward and inverse solutions of the kinematics were obtained.A group of optimal solutions were obtained according to the principle of minimum sum of rotation angles of each joint and specific trajectory path requirements.Using the method of differential transformation,the Jacobian matrix relative to the base coordinate system is solved.According to the Lagrange-method,the dynamics model of the 6-DOF cooperative robot was established,and the dynamics parameters were obtained.According to the dynamics model,the second-order differential equation of the cooperative robot was obtained,and the impedance controller of the robot was established.The robot's kinematics,differential motion and dynamics models were verified by using the Robotics Toolbox in Matlab.(2)The cooperative robot control system takes the embedded industrial computer as the control platform,realizes the cooperative control of various joints of the industrial robot through the industrial field bus,and designs the control system based on Ether CAT bus and Twin CAT3 software.The joint module of the robot is used as the slave station of Ether CAT bus,and Twin CAT3 is used as the controller to control the manipulator arm.HMI and Twin CAT Measurement Scope View is used to develop the human-machine interface and realize the field debugging.This paper mainly designs the control system of the cooperative robot from three aspects: low-level communication,program and logic,and HMI human-machine interaction interface.(3)The TA6-R5 cooperative robot was used as the experimental platform,and the joint space and Cartesian space motion experiments,photogrammetric experiment based on drag teaching and polishing experiments of the cooperative robot based on impedance control were carried out.The results show that the cooperative robot can realize motion control,drag teaching and force control based on impedance control,and the cooperative robot control system has high stability and reliability.