Towards Manipulability of Bilateral Teleoperators With Time-Varying Delay

In this paper, we systematically formulate the concept of infinite (dynamical) manipulability for general dynamical systems, and by exploiting this concept to develop a new class of dynamic feedback, we solve the problem of bilateral control for nonlinear teleoperators with arbitrary bounded unknown time-varying delay. Specifically, based on a new dynamic feedback design of the reference velocities and accelerations, we propose an adaptive controller for nonlinear teleoperators that is robust with respect to arbitrary bounded unknown time-varying delay. It is shown that the proposed controller achieves position synchronization of the master and slave robots in free motion. In addition, the proposed controller ensures static torque reflection and the infinite manipulability of the teleoperator system with degree one provided that the gravitational torques are compensated a priori. The performance of the proposed adaptive controller is shown by numerical simulation results.