Adaptive Inverse Dynamics Four-Channel Control of Uncertain Nonlinear Teleoperation Systems

Most of the methods to date on bilateral control of nonlinear teleoperation systems lead to nonlinear and coupled closed-loop dynamics, even in the ideal case of perfect knowledge of the master, the slave, the human operator and the environment. Consequently, the transparency of these closed-loop systems is difficult to study. In comparison, inverse dynamics controllers can deal with the nonlinear terms in the dynamics in a way that, in the ideal case, the closed-loop systems become linear and decoupled. In this paper, for multi-d.o.f. nonlinear teleoperation systems with uncertainties, adaptive inverse dynamics controllers are incorporated into the four-channel bilateral teleoperation control framework. The resulting controllers do not need exact knowledge of the dynamics of the master, the slave, the human operator or the environment. A Lyapunov analysis is presented to prove the transparency of the teleoperation system. Simulations are also presented to show the effectiveness of the proposed approach.