Bilateral Teleoperation System in the Presence of Non-passive Interaction Forces and Actuators Fault

This paper addresses the asymptotic stability, position and force tracking problem in the nonlinear bilateral teleoperation system in the presence of non-passive interaction forces, varying time-delay in communication channel and actuators fault occurrence. For this aim, a passive Fault Tolerant Control (FTC) law is presented which uses the joint positions and velocities of local and remote manipulators to reach control ends. Using the Lyapunov-Krasovskii theorem, sufficient conditions for asymptotic stability and position tracking are derived in terms of Linear Matrix Inequalities (LMIs), to tune controller parameters. The main contribution of the proposed method is that can compensate the bias fault and loss of effectiveness of actuators in nonlinear teleoperation system. Also the asymptotic stability of positions errors in the system with non-passive interaction forces is assured using the integral control. Simulation results of teleoperation system with 2 and 3 degrees of freedom manipulators with proposed method and comparison to some rival methods show the effectiveness and advantages of the proposed method.