Nonlinear output regulation for invertible nonlinear MIMO systems

In this paper, we address the problem of output regulation for a broad class of multi-input multi-output (MIMO) nonlinear systems. Specifically, we consider input-affine systems, which are invertible and input-output linearizable. This class includes, as a trivial special case, the class of MIMO systems which possess a well-defined vector relative degree. It is shown that if a system in this class is strongly minimum phase, in a sense specified in the paper, the problem of output regulation can be solved via partial-state feedback or via (dynamic) output feedback. The result substantially broadens the class of nonlinear MIMO systems for which the problem in question is known to be possible. Copyright (C) 2015 John Wiley & Sons, Ltd.