Fuzzy pole placement design with H∞ disturbance attenuation for uncertain nonlinear systems

In this paper, pole placement design combined with H_∞ disturbance attenuation is discussed for a class of uncertain nonlinear dynamical systems. The D-subset is defined by a LMI region in the complex plane, and the nonlinearities are described by Takagi-Sugeno fuzzy models. Focusing on the disturbance attenuation, the conventional fuzzy H_∞ controller paid no heed to transient behavior. This paper proposes a controller design, which makes a compromise between above two performance indexes. Since both the existing fuzzy H_∞ controller and the D-stabilizable controller are obtained by the feasibility of grouped linear matrix inequalities (LMI´s), the pole placement design with H_∞ disturbance attenuation can be solved by simply uniting all the LMI´s. A mass-spring-damper system is selected to illustrate the results.