Bilateral continuous terminal sliding mode control for teleoperation systems with high-order disturbances

A new bilateral continuous terminal sliding mode control method is proposed to attenuate the high-order time-varying disturbance in teleoperation systems based on enhanced nonlinear disturbance observer (ENDOB). Firstly, the control task of the teleoperation systems is transformed into stabilization of the position and force tracking errors. And then, the ENDOBs are introduced to estimate the high-order lumped disturbances in position and force tracking error subsystems. Finally, based on the estimation of lumped disturbances, a bilateral continuous terminal sliding mode controller is developed. The proposed bilateral controller not only guarantees the continuity of the control action but also guarantees the position and force tracking errors converge to a small bounded region even when there exist high-order time-varying disturbances. The effectiveness of the proposed method is validated by its applications on a bilateral lift robot system.