Task Space Robotic Manipulation Based on Revised Virtual Decomposition Plus PD Control

Because of the issues of amount of computation with the Lagrange equation, a subsystem dynamics based control method called virtual decomposition, which virtually decomposes robot manipulator into links and joints, was proposed. However, due to unknown and complexity of robotic joint parameters, the use of virtual decomposition control is limited, especially at the beginning of design of the manipulator. To solve this problem and make the simulation and experiment of multi-degree of freedom of robot become much easier and executable, a revised virtual decomposition control based entirely on the link and ignoring the joint (i.e., the motor or other actuator) is proposed. In order to make the system more robust, a compound control scheme combining revised virtual decomposition control with PD control is proposed. The stability analysis of overall robotic system is given according to Lyapunov function. Finally, simulations of six-degree of freedom of robot are presented.