Control of a delayed teleoperation system applying state convergence approach

This article presents a novel control scheme for bilateral teleoperation of n degree-of-freedom (DOF) nonlinear robotic systems with time-varying communication delay. The bilateral control of the teleoperator system considers the case were the human operator applies a constant force on the local manipulator and when the interaction of the remote manipulator with the environment is considered passive. The stability analysis was performed using Lyapunov-Krasovskii functionals, and it showed that using a control scheme by state convergence for the cases with variant time delay resulted in asymptotically stable local and remote nonlinear teleoperation systems. The proposed control strategies are independent of parameter uncertainties in the robot models, the human operator and the remote environment. It is also shown that, in the case of reliable communication protocols, the proposed scheme guarantees that the local-remote position coordination is achieved. The experimental results are presented to show the effectiveness of the main results.