New Results to Verify the Robust Stability Property of Interval Plants with Time-Delay1

This paper presents a sufficient condition to verify the robust stability property of a class of time delay systems which are described as an interval plant with uncertain time delay. The main result is obtained on the basis of some polynomials that can be easily computed using Kharitonov's polynomials. This contribution considers the delay with interval uncertainty, since in most of the research reports only fixed delay is considered. The present work bases its results on the value set characterization for interval plants with uncertain time delay along with the use of the zero exclusion principle to compute the robust stability property of the close loop system.