A fuzzy adaptation technique for sliding mode controllers

Abstract

In this study a new fuzzy adaptation technique to be used in a sliding mode controller is developed for achieving robust tracking of nonlinear systems, Since conventional sliding mode control strategies suffer from high control gain and chattering problems a fuzzy adaptation for a sliding mode controller is proposed to overcome the problems. In the approach two fuzzy approximators are employed in such a way that the slope of the linear surface is updated by the first fuzzy approximator, to shape tracking error dynamics in the sliding regime, while a second fuzzy approximator regulates behaviour of the states in the reaching phase. Thus the fuzzy adapted sliding mode controller proposed in this study pushes the system states in the most appropriate way to achieve robust tracking. Examples demonstrate that results are highly satisfactory for both dynamics and steady-state responses, hence the method is confirmed through the simulations.