Lyapunov-based bilateral teleoperation for surgical robotic forceps system with time varying delay

Abstract

This paper addresses a new approach of bilateral control for a class of teleoperation systems with time-varying delay and its applications to bilateral teleoperation of robotic surgical device for minimally invasive surgery (MIS). A Lyapunov function-based bilateral control law for one-DOF teleoperation system that is capable of motion scaling in both position and force tracking is proposed so as to guarantee stability of the teleoperation system in the presence of time-varying delay. The proposed bilateral control law is adopted in vertical direction and horizontal direction for bending direction of the multi-DOF robotic forceps, respectively. Then, together with change of coordinates, the proposed bilateral control scheme is extended so that it may become applicable to bilateral control of omnidirectional bending of the multi-DOF robotic forceps manipulator incorporating a new screw-drive mechanism termed double-screw-drive mechanism. Thus, a scalable surgical device for MIS that can provide force feedback to surgeon is presented in this paper. In order to verify the effectiveness of the proposed bilateral control scheme, experimental works were carried out for the developed robotic forceps teleoperation test-bed for MIS.