A robust filter and controller design for NCS with uncertainties and data dropouts

Abstract

In this paper, a Robust Networked Control System (RNCS) subject to data losses constraints is considered. The design will be composed by the calculation of a filter and the synthesis of an H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∞</sub> controller. Both designs will have two purposes. The first one is to robustify the controlled system against plant uncertainties. The other one is the output estimation of the plant so the feedback is not zero when a packet dropout occurs. Data losses are modelled as an independent sequence of i.i.d. Bernoulli random variable. It is also considered that only one consecutive packet dropout may occur. Also, structural uncertainties in the model of the plant are considered. To cope with this problem, a robust filter and an H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∞</sub> control technique are proposed in this work. These filter and controller will be synthesized in order to make the closed-loop system robust enough against structural uncertainties of the nominal model. The filter also is able to deal with network data losses.