Reduced-order dynamic output feedback control of continuous-time T–S fuzzy systems

The problem of reduced-order dynamic output feedback control design for continuous-time Takagi–Sugeno fuzzy systems with H ∞ guaranteed cost is addressed. The proposed approach is based on a line-integral fuzzy Lyapunov function with arbitrary polynomial dependence on the premise variables, allowing the membership functions, modeled as multi-simplexes, to vary arbitrarily. The controller is obtained by transforming the problem into a static output feedback control design problem solved by means of a two-stages linear matrix inequality procedure. The main appeal of the approach is that the order of the output feedback controller as well as the dependence of the premise variables are customizable for control implementation purposes. Examples illustrate the flexibility of the method and also that the proposed strategy can provide less conservative results when compared to other methods for full order dynamic output feedback controllers from the literature of continuous-time Takagi–Sugeno fuzzy systems.