Delay-dependent robust H_∞ output tracking control for uncertain networked control systems

In this paper, the H_∞ output tracking problem for networked control systems (NCSs) liable to model uncertainties and with delays varying within intervals is investigated. A new method is proposed to the robust H_∞ output tracking analysis and control design for NCSs. The results presented here are an improvement over previous ones, for the analysis incorporates state-of-the-art stability techniques for systems with time-varying delays such as convex optimization technique, piecewise analysis method, and a new delay fractioning approach with the introduction of a novel auxiliary delayed state. The analysis is enriched with a numerical example that illustrates the advantages of our criteria which outperform previous criteria in the literature. Moreover, an illustrative example shows the effectiveness of the proposed H_∞ output tracking control design.