UNIVERSAL OUTPUT FEEDBACK CONTROL OF NONLINEAR SYSTEMS WITH UNKNOWN GROWTH RATE

Abstract

This paper investigates the problem of global stabilization by output feedback for a family of uncertain nonlinear systems dominated by a triangular system satisfying linear growth condition. In contrast to the previous work in the literature, the growth rate here is a positive constant but not known a priori, and therefore the problem cannot be addressed by the existing output feedback control schemes. Using the idea of universal control integrated with the recent output feedback design method that is not based on the separation principle, we construct a universal-type output feedback controller which globally regulates all the states of the uncertain systems without knowing the growth rate. We also discuss briefly how this result can be extended to a larger class of nonlinear systems with unknown parameters.