Research Of Semi-physical System On 6-DOF Manipulator

Manipulators have been widely used in many fields, such as industry, medicine, aerospace and education. Research of manipulator is of great value. This paper researches a semi-physical system of six degrees of freedom(6-DOF) manipulator, installing the virtual simulation system of manipulator and physical control system of 6-DOF manipulator.Firstly, with the 6-DOF manipulator as a research object, forward and inverse kinematical model is derivated by Denavit-Hartenberg(D-H) method, and dynamical modeling is based on Lagrange method.Second, trajectory plan methods and control algorithms of manipulator are studied. Both of fixed step and variable step interpolation are adopted in Cartesian space for a line trajectory and an arc trajectory for the 6-DOF manipulator. The simulation results show that variable step interpolation can make the manipulator start and stop smoothly. An adaptive nonsingular terminal sliding mode control(ANTSMC) algorithm with modified switch function is used in trajectory tracking control task. The simulation results show that the modified switch function decreases the chattering of control torque effectively.Third, virtual simulation platform on a 6-DOF manipulator is built, which includes virtual modeling, 3D virtual simulation and GUI interface. By using virtual simulation platform, 3D visual simulation of the kinematics, trajectory plan and control algorithm of 6-DOF manipulator could be complished.Finally, physical control platform of 6-DOF manipulator is installed by using two-level control structure of PC with CAN bus and DSP control circuit board. The trajectory plan and control algorithm are carried out on the physical platform, and the experiment results are satisfactory.