Global output feedback stabilization for a class of nonlinear time-varying delay systems

This paper investigates the problem of global stabilization by output feedback for a class of nonlinear systems with time-varying delays. The uncertain nonlinearities are assumed to satisfy a polynomial growth condition. We first design an output feedback stabilizer to globally stabilize the nominal system without the perturbing nonlinearities. Then based on the homogeneous domination approach and the appropriate Lyapunov–Krasovskii functional, a scaling gain is introduced into the proposed output feedback stabilizer to render the closed-loop system globally asymptotically stable. Two simulation examples are given to illustrate the effectiveness of the proposed design scheme.