Discrete-time fuzzy modeling and control & its application

Discrete-time fuzzy modeling and state feedback control are investigated for nonlinear systems. The considered nonlinear system is firstly estimated by a discrete-time T-S fuzzy model. A fuzzy state feedback controller is designed. The sufficient conditions for the existence of controller are derived via a linear matrix inequality (LMI) approach. The designed controller not only can guarantee that the closed-loop system is asymptotically stable and but also can get good control performances. The gains of controller are obtained by solving a set of LMIs. The presented approach is applied to control helicopter systems. In contrast to the existing results, the proposed method has several advantages: i). Transient time is short; ii). There is no overshoot; iii). External disturbances can be effectively reduced. A CE150 helicopter system example is given to show the effectiveness of our scheme.