Fuzzy Model Based Bilateral Control Design of Nonlinear Tele-Operation System Using Method of State Convergence

Abstract

This paper presents the design of a state convergence (SC)-based bilateral controller for a nonlinear teleoperation system, which has been approximated by a Takagi–Sugeno (TS) fuzzy model. The selection of SC is made due to the advantages offered by this scheme both in the modeling and control design stages. The modeling stage considers master/slave systems, which can be represented by the $n$ th order differential equations, while the control design stage offers an easy way to determine the control gains required for assigning desired closed loop dynamics to teleoperation system. After the master/slave systems are represented by TS fuzzy models, a stabilizing fuzzy law is adopted which allows deploying the SC scheme with all its benefits to design the fuzzy bilateral controller. In this way, not only the simplicity of the design scheme is ensured but also the existing SC scheme is able to control a nonlinear teleoperation system based on its TS fuzzy model description. As an additional advantage, the SC-based existing linear bilateral controller can be easily derived from the SC-based proposed fuzzy bilateral controller. Various cases of master/slave systems originally reported in terms of their linear model representation and communication in the absence/presence of time delay are all discussed in the corresponding fuzzy framework. The MATLAB simulations, considering a one-degree-of-freedom teleoperation system, are performed to validate the proposed methodology for controlling a nonlinear teleoperation system.