Adaptive multiple estimation fault-tolerant control for teleoperation systems with deferred time-varying output constraints

Abstract

This study investigates the synchronization tracking problem for a class of nonlinear teleoperation systems subjected to time-varying output constraints and actuator failures. The shifting function and the asymmetric barrier Lyapunov function are employed to ensure that the system's output constraints are satisfied regardless of whether the initial condition is within the constraint boundary or not. As a result, the strict assumption in most references dealing with constraint issues is effectively removed. Meanwhile, multiple estimation techniques involving neural networks and disturbance observers are utilized to approximate actuator failures and lumped uncertainty of the teleoperation system. Following this, an adaptive multiple estimation fault-tolerant control scheme is proposed to achieve synchronization tracking of teleoperation systems. Finally, simulations and experiments are implemented to verify the feasibility and availability of the proposed control scheme with the teleoperation platform composed of two Phantom Omni 3D Touch robots.