A graph-oriented approach to address generically flat outputs in structured LTI discrete-time systems. (August 2022)

• Record Type: Journal Article
• Authors: Boukhobza, Taha; van der Woude, Jacob; Commault, Christian; Millérioux, Gilles
• Is Part Of: Automatica. Volume 142(2022)
• Publication Date: 2022-08
• Subjects: Structured linear systems -- Flatness -- Graph theory; Automatic control -- Periodicals; Automation -- Periodicals; 629.805
• DOI: 10.1016/j.automatica.2022.110344
• Languages: English
• ISSNs: 0005-1098

Abstract

Abstract: This paper addresses difference flatness for structured LTI discrete-time systems. Two forms of necessary and sufficient conditions for an output to be a structural flat output are given. First, a preliminary result algebraically defines a flat output in terms of invariant zeros regardless whether an LTI system is structured or not. Next, the conditions are expressed in terms of graphical conditions to define a structural flat output. Checking for the graphical conditions calls for algorithms that have polynomial-time complexity and that are commonly used for digraphs. The tractability of the conditions is illustrated on several examples.