A stable perturbation estimator in force-reflecting passivity-based teleoperation

Abstract

Many researchers have focused on force tracking improvement in teleoperation systems. Various methods have been utilized to reach this aim. This paper focuses on force-reflecting passivity-based architecture. Adding a force error term to conventional passivity-based architecture, a controller has been introduced to improve transparency. A condition has been obtained, which guarantees the stability of the system, while it holds. Moreover, a sliding mode perturbation estimation algorithm has been proposed. The method proved to be asymptotically converging to perturbations. The transparency of system has been compared in simple and force-reflecting passivity-based architectures, and also with and without perturbation estimator. Experiments on a 2-DOF non-linear delayed teleoperation system were conducted to investigate the system’s performance. Experimental results have shown that the controller is stable and force tracking has been improved compared with previous research. Furthermore, the perturbation in the system has been successfully estimated and cancelled. Conclusively, the paper introduces a controller that is stable and compares its performance in force tracking with previous research.