An Optimization Approach For The Computation Of The Minimum Destabilizing Uncertainty Volume

In this paper we propose an non-linear optimization based algorithm for the computation of the stability region for uncertain polynomials. Examples are presented in illustration

Approximation Of Time-Delay Systems

We propose a new method for approximating time-delays in dynamical systems. A weighted II-infinity norm criterion is minimized to obtain rational approximation of e(-sd). We report the approximation in a diagram relating both the amount of time delay and the bandwidth to the order of the approximating rational function for a given level of infinity norm. The obtained approximations are compared to the widely used Fade's approximation. Examples are used for illustrations

H-Infinity Error Bounds In Approximating Time-Delay Systems

In this paper, upper and lower bounds on approximating time-delay systems are proposed. Bounds on the infinity norm of the weighted error are obtained when the approximating function is a general rational function, an all-pass function or Pad and Laguerre approximations. In addition, approximations of the weighted errors for both Pade and Laguerre approximating functions are developed. Examples are presented in illustration