Nonlinear composite bilateral control framework for n-DOF teleoperation systems with disturbances

This paper proposes a new nonlinear composite bilateral control framework for n-degree-of-freedom (n-DOF) teleoperation systems with external disturbances. Different with the existing methods which usually regard the dynamics of the master and slave robots as linear impedance models, the proposed control framework fully considers the nonlinear dynamics of the n-DOF teleoperation systems. Central to the proposed framework is the utilization of nonlinear disturbance observers for estimating the disturbances in master and slave robot systems. The nonlinear composite bilateral controller is constructed by incorporating the disturbance estimations into the nonlinear feedback linearization controller. The proposed control method guarantees satisfactory position tracking performance and desired remote force haptic simultaneously for the n-DOF teleoperation systems with external disturbances. The effectiveness of the proposed control framework is validated by its applications on 2-DOF teleoperation systems