Einladung zum Vortrag im Kolloquium Technische Kybernetik

  Information Flows in
Cooperative Networked Control Systems

Prof. Girish Nair
Department of Electrical and Electronic Engineering
The University of Melbourne
Carlton, Victoria, Australia

    Zeit: Dienstag 3. 3. 2009 · 16:00 Uhr
    Ort: IST Seminarraum 3.243 · Pfaffenwaldring 9 · Campus Stuttgart-Vaihingen

Abstract

The control-theoretic equivalent of Ahlswede et al's network information theory is the problem of determining the rates at which information must flow between system components in order to be able to cooperatively achieve closed loop stability. This talk considers the case of a linear, time-invariant plant with multiple sensors and actuators that communicate with each other over a network of directional digital channels with finite bit rates. By defining a new information measure, it is shown that for a broad class of networks, a fluid-like interpretation of information flow is possible. This leads to a necessary and almost sufficient condition for determining uniform stabilisability, in terms of the feasibility of a set of linear inequalities in the unstable eigenvalues of the plant and the bit rates of the channels. This provides an exact characterisation, up to boundary points, of the region of all stabilising channel bit rate vectors. When channel rates are set to either zero or infinity, this agrees with classical results on decentralised stabilisability under linear, time-varying control.

Biographical Information

Dr. Girish Nair is an Associate Professor in the Department of Electrical and Electronic Engineering at the University of Melbourne, Australia, with research interests in the overlap between feedback control and communications. He is a recipient of the 2006 Outstanding Paper Prize of the Society for Industrial and Applied Mathematics (SIAM), USA and the Best Theory Paper Prize at the UKACC International Control Conference in Cambridge, UK, 2000. He serves as an associate editor for SIAM Journal on Control and Optimizationand is an editorial board member for IET Control Theory & Applications (UK).