Sampled-Data Output Feedback Stabilization of a Family of High-Order Systems with Delays

Sampled-data control via output feedback is studied for a family of strongly nonlinear systems with state and input delays. Under sample and hold, a delay-free output feedback control scheme is developed based on the emulation method, adding a power integrator (AAPI) technique, and recursive design of nonlinear observers. With the aid of Lyapunov-Krasovskii functional theorem, together with the idea of homogeneous domination, we prove that the proposed sampled-data output feedback controller makes the hybrid closed-loop systems with delays and uncertainty globally asymptotically stable, if the input delay and sampling period are limited. The family of time-delay uncertain systems under consideration goes beyond the Lipschitz or linear growth condition and is genuinely nonlinear as it contains uncontrollable/unobservable linearization and is not stabilizable, even locally, by any linear or smooth feedback. Application of the sampled-data control scheme presented in this paper is illustrated by an example with simulation.