Position synchronization for an uncertain teleoperation system with time delays using L1 theory

The problem of position tracking in teleoperation systems equipped with latencies and dynamical uncertainties was addressed in this study. In many applications, such as telesurgery, safe interaction with the external environment is a factor that may undermine the synchronization of the positions. In the case of nondestructive contact with the environment, in addition to an errorless steady-state position tracking, the closedloop system requires a response with the least possible overshoot. To this end, a statefeedback controller based upon L1 theory was proposed in this paper. The compensator was synthesized using Linear Matrix Inequality (LMI) technology, and the asymptotic stability of the system was verified through Lyapunov-Krasovskii functional. Considered its advantage, the proposed control scheme is robust to asymmetric randomly varying time delays in the communication channels. The L1-based controller was finally compared to the well-known sliding mode controller through simulation, and it proved to outperform its counterpart from the maximum error point of view while preserving low steady-state error. The proposed controller was also proved to be effective even in the presence of model uncertainties.