H-infinity control for more general nonlinear systems

In this paper, we consider the standard H-infinity control problem for more general nonlinear systems modeled by equations in which the penalty output z and the measured output y are, in general, functions of both the exogenous input w and the control input u. In particular, we characterize a family of H-infinity controllers via output feedback, as well as state feedback, solving the problem. The results obtained in this paper generalize some recent results in the literature.