On the estimate of robustness bounds for perturbed time-delay systems

The stability robustness problem is considered for linear time-delay systems with perturbations. Both the nonlinear time-varying perturbation and the linear highly structured parametric perturbation are discussed. Applying Lyapunov stability theorem and time-domain analysis methods, we derive several criteria such that the upper bounds on norms of time delay and the perturbations can be estimated to guarantee the asymptotic stability of these systems in the presence of time delay and perturbations. Numerical examples are given to demonstrate the effectiveness of the quantitative results