Mechanical design, implementation and tracking control of a seven degree of freedom redundant manipulator using discontineous Lyapunov-based controller

One of the main objectives of designing robotic systems is to design structures, capable of performing multi tasks. Redundant manipulators by having high degrees of freedom, expand the end-effectors' workspace and are widely used as multi-task systems. In this paper, mechanical design, kinematic and dynamic analyses, implementation of mechanical part and electronic hardware and control of a redundant 7-DOF robotic manipulator, based on the upper extremity structure of the human body has been addressed. The discontinuous Lyapunov-based controller is used, which comprises of integral operator and tracking controller. The goal is to improve the tracking performance of the robot manipulator in the presence of bounded and time variant disturbances. The proposed trajectory, relaxes the need of having knowledge about nonlinear dynamics. Based on the disturbance rejection scheme, tracking controller has been constructed which was asymptotically stabilizing in the sense of Lyapunov. Simulation results showed that the closed loop system strongly rejects disturbances.