EXPONENTIAL ESTIMATES FOR TIME DELAY SYSTEMS USING FUNCTIONALS WITH DERIVATIVE OR DELAYED TERMS

In this contribution, we explain that using Lyapunov Krasovskii functionals with time derivative terms for the determination of exponential estimates of the system response restrict the scope of the results. We show that it is possible to overcome this limitation by introducing delayed states in the functional. The case of linear time delay systems of retarded type is analyzed and it is shown that our results match or improve existing results in the literature.