Characterization of flat outputs for LPV discrete-time systems: A graph-oriented approach

This paper deals with the characterization of flat outputs for LPV discrete-time systems. As a clue to tackle the problem, we consider an LPV system as a linear structured system. Then, for this class of systems, necessary and sufficient conditions for an output to be a flat output are given in terms of graphical conditions. The conditions can be checked by resorting to well-known algorithms commonly used for digraphs. As a result, the proposed solution is simple to implement and has polynomial complexity.