State feedback controller for a class of MIMO non triangular systems

Abstract This paper presents a controller design for a class of MIMO nonlinear systems involving some uncertainties. The latter is particularly composed by cascade subsystems and each subsystem is associated to a subset of the system outputs and assumes a triangular dependence on its own state variables and may depend on the state variables of all other subsystems. The main contribution consists in extending the available control results to allow more interconnections between the subsystems. Of fundamental interest, it is shown that the underlying tracking error exponentially converges to zero in the absence of uncertainties, and can be made as small as desired by properly specifying the control design parameter in the presence of uncertainties.