Adaptive dynamic output feedback control of Takagi-Sugeno fuzzy systems with immeasurable premise variables and disturbance

Unlike in the literature, premise variables of the Takagi-Sugeno (TS) fuzzy system is assumed to be not measurable, and an adaptive output feedback control law is designed for the given system. Additionally, the system under investigation is considered to be subjected with both parameteric uncertainty and disturbance. Unlike other control designs, the bound on parameter uncertainty term is relaxed. Further, the adaptive control law utilizes estimated premise variables and online approximator. Note only one approximator is used to estimate both the parameter uncertainty and disturbance. Therefore, the proposed control design is simplified. This control design is guaranteed to render a stable closed loop TS fuzzy system. Detailed analytical results using Lyapunov theory are presented to guarantee stability. Finally, a simulation example is used to illustrate the performance of the proposed adaptive output feedback control law.