Mathematical Problems in Engineering
Volume 2012 (2012), Article ID 768212, 22 pages
http://dx.doi.org/10.1155/2012/768212
Research Article

Linear Matrix Inequalities in Multirate Control over Networks

Departamento de Ingeniería de Sistemas y Automática, Instituto Universitario de Automática e Informática Industrial, Universitat Politecnica de Valencia, Camino de Vera, s/n, 46022 Valencia, Spain

Received 4 June 2012; Revised 19 July 2012; Accepted 23 July 2012

Academic Editor: Bo Shen

Copyright © 2012 Ángel Cuenca et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This paper faces two of the main drawbacks in networked control systems: bandwidth constraints and timevarying delays. The bandwidth limitations are solved by using multirate control techniques. The resultant multirate controller must ensure closed-loop stability in the presence of time-varying delays. Some stability conditions and a state feedback controller design are formulated in terms of linear matrix inequalities. The theoretical proposal is validated in two different experimental environments: a crane-based test-bed over Ethernet, and a maglev based platform over Profibus.