Robust PI adaptive fuzzy control for a class of uncertain nonlinear systems

A robust PI adaptive fuzzy controller for a class of uncertain nonlinear systems is investigated. The proposed method is robust in the presence of uncertainties and bounded external disturbances. To cope with the lack of system structure and signal uncertainty the adaptive fuzzy control is used. Furthermore, a PI-type control is introduced to cope with the bounded disturbances, which also provides robustness in the presence of large disturbances. Asymptotic stability of the proposed method is shown based on Lyapunov approach. Application of the proposed method to an inverted pendulum system demonstrates the effectiveness of the proposed approach.