Graphical characterization of the set of all flat outputs for structured linear discrete-time systems

This paper deals with the characterization of flat outputs for structured linear discrete-time systems. More precisely, considering a structured discrete-time linear system, we provide a complete set of the flat outputs using constructive polynomial complexity order algorithms. The proposed method is simple to implement. It is based on usual algorithms dedicated to the computation of successors and predecessors of vertex subsets and to the computation and the ordering of strongly connected components in a digraph.