Robustness of Nonlinear Delay Equations with Respect to Input Perturbations: a Trajectory-Based Approach

 The effect of input perturbations on the stability properties of nonlinear time-varying delay differential equations is studied from a trajectory-based point of view. Thereby the semi-global stability results from MSR2], where a Lyapunov approach is taken, are broadened to a much larger class of delay differential equations. Applications to the stabilization of partially linear cascade systems with delay using partial state feedback are briefly outlined. Date received: January 9, 2001. Date revised: April 15, 2002. RID="*" ID="*"This paper presents research results of the Belgian programme on Interuniversity Poles of Attraction, initiated by the Belgian State, Prime Minister's Office for Science, Technology and Culture (IUAP P4/02). The scientific responsibility rests with its authors. Luc Moreau is a Postdoctoral Fellow of the Fund for Scientific Research—Flanders (Belgium) (F.W.O.-Vlaanderen) and a recipient of an Honorary Fellowship of the Belgian American Educational Foundation. Part of this work was done while Luc Moreau was supported by a BOF grant of the Ghent University.