Robust unknown input observers for nonlinear time-delay systems
Résumé
In this paper we address the problem of robust unknown input observer design for continuous nonlinear time-delay systems. To investigate the robustness of the studied system, we compare two approaches, the first based on a standard $\mathcal{H}_{\infty}$ method and the second with Sobolev norms. New sufficient synthesis conditions are given in linear matrix inequality form.