Output feedback fuzzy adaptive control for a class of large-scale nonlinear systems

Hybrid stable output feedback decentralized control schemes are presented for a class of uncertain large scale nonlinear systems for which the state variables are unavailable for feedback. These hybrid indirect control algorithms consist of three different control components. The adaptive fuzzy logic system plays a dominant role to maintain the whole closed-loop stability. Being the auxiliary compensation, a sliding mode control is designed to compensate for the interactions between subsystems and a H^∞ control is designed to attenuate fuzzy approximation errors. Thus, this hybrid output feedback adaptive fuzzy decentralized controller can guarantee the global stability of the closed-loop, and achieve a good tracking performance as well. The simulation results verify the effectiveness of the proposed controller.