Chattering-free adaptive fuzzy sliding mode control

An adaptive fuzzy sliding mode control (AFSMC) for uncertain dynamic systems is presented in this paper. Chattering problem in classical sliding mode control (CSMC) is highly undesirable because it may excite unmodeled high frequency plant dynamics and leads to unforeseen instabilities. The proposed approach in this paper completely eliminates the chattering by using adaptive fuzzy system to calculate continuous control gain vector instead of discontinuous one in classical sliding mode control. Mathematical proof for the stability and the convergence of the system is also presented to show its validity theoretically. The proposed approach and the classical sliding mode control are both applied to a flexible transmission system in order to illustrate how the new approach can eliminate the chattering in this control strategy.