Nonlinear control of a non-passive bilateral teleoperation in presence of unsymmetric time varying delay

This paper represents a controller design for nonlinear bilateral teleoperation systems. The proposed controller is used when both terminals of teleoperation system are considered to be non-passive. Moreover, the communication channel is subjected to unsymmetrical time varying delays. A good example of such systems is robotic telerehabilitation therapy in both assistive and resistive mode. The controller is comprised delayed position-position architecture and nonlinear adaptive controller to deal with parameters uncertainty in environment dynamic. On the other hand, a new Impedance reflection term is considered in the master controller for improving transparency. The stability of closed-loop teleopration system is established by a Lyapunov-Krasovskii function. Finally, the proposed scheme is utilized on a pair of planner 2-DOF robots to show performance and accuracy of the proposed controller.