Abstract
This paper presents a novel approach to the robust H∞ control problem for uncertian nonlinear systems with stable zero-dynamics. The uncertainty is described by unknown but gain bounded functions of the state variables. A parametrization of a class of robust stabilizing control laws is derived for the uncertain systems, and a solution to the robust H∞ control problem is obtained by constructing a storage function based on the Lyapunov function of robustly stable zero-dynamics.
