eprintid: 479 rev_number: 13 eprint_status: archive userid: 7 dir: disk0/00/00/04/79 datestamp: 2011-07-27 08:36:50 lastmod: 2011-08-05 13:03:30 status_changed: 2011-07-27 08:36:50 type: article metadata_visibility: show contact_email: alberto.bemporad@imtlucca.it item_issues_count: 0 creators_name: Alessio, Alessandro creators_name: Lazar, Mircea creators_name: Bemporad, Alberto creators_name: Heemels, W.P.M.H. creators_id: creators_id: creators_id: alberto.bemporad@imtlucca.it creators_id: title: Squaring the circle: an algorithm for generating polyhedral invariant sets from ellipsoidal ones ispublished: pub subjects: QA divisions: CSA full_text_status: none keywords: Positively invariant sets; Contractive sets; Model predictive control; Stability; Robust stability abstract: This paper presents a new (geometrical) approach to the computation of polyhedral (robustly) positively invariant (PI) sets for general (possibly discontinuous) nonlinear discrete-time systems possibly affected by disturbances. Given a β-contractive ellipsoidal set View the MathML source, the key idea is to construct a polyhedral set that lies between the ellipsoidal sets View the MathML source and View the MathML source. A proof that the resulting polyhedral set is contractive and thus, PI, is given, and a new algorithm is developed to construct the desired polyhedral set. The problem of computing polyhedral invariant sets is formulated as a number of quadratic programming (QP) problems. The number of QP problems is guaranteed to be finite and therefore, the algorithm has finite termination. An important application of the proposed algorithm is the computation of polyhedral terminal constraint sets for model predictive control based on quadratic costs. date: 2007 date_type: published publication: Automatica volume: 43 number: 12 publisher: Elsevier pagerange: 2096-2103 id_number: 10.1016/j.automatica.2007.04.028 refereed: TRUE issn: 0005-1098 official_url: http://www.sciencedirect.com/science/article/pii/S0005109807003032 citation: Alessio, Alessandro and Lazar, Mircea and Bemporad, Alberto and Heemels, W.P.M.H. Squaring the circle: an algorithm for generating polyhedral invariant sets from ellipsoidal ones. Automatica, 43 (12). pp. 2096-2103. ISSN 0005-1098 (2007)