Internet-Based Bilateral Teleoperation: A Review and Future Directions with UDP and Event-Based Control

Abstract

A survey is done of various results in the control of bilateral teleoperation systems in order to determine the best control scheme for telesurgery over the internet. Telesurgery is a particularly demanding application where the challenges imposed by the internet, including time-varying delay, lost packets and out-of-order packets, must be addressed to try to maximize performance. The nature of delay on IP networks and the merits of UDP as a transport protocol are investigated and out-oforder packets are shown to have the same effect as lost packets. Stochastic models can be used to characterize packet delay. Passivity-based, predictive, robust & optimal and event-based control are discussed with respect to teleoperation. When timevarying delays are introduced, the system becomes a hybrid event-time based system. Future work is proposed that would consider a delay model that incorporates knowledge of lost and out-of-order packets to be incorporated into a hybrid event-time predictive control scheme.