ROBUST OUTPUT FEEDBACK CONTROL FOR UNCERTAIN FUZZY SYSTEMS WITH IMMEASURABLE PREMISE VARIABLES

Jun Yoneyama (Japan)

Received October 4, 2007

Abstract

This paper discusses robust output feedback control of Takagi- Sugeno fuzzy systems with immeasurable premise variables. When we consider the output feedback control of Takagi-Sugeno fuzzy systems, the selection of premise variables plays an important role. If the premise variable is the state of the system, then a fuzzy system describes a wide class of nonlinear systems. However, the state is not measurable in the output feedback control problem. In this case, a control design of the underlying nonlinear system based on parallel distributed compensation (PDC) concept is infeasible because a controller depends on the immeasurable state variable. In this paper, we formulate this fuzzy control problem as a robust control of an uncertain system. Finally, a numerical example is given to illustrate our methods.

Keywords and phrases: Takagi-Sugeno fuzzy systems, output feedback control, premise variables, disturbance attenuation, uncertain systems.