Global adaptive output feedback stabilization for nonlinear time-delay systems with unknown measurement sensitivity

In this article, a global output feedback stabilization scheme is proposed for a class of time-delay uncertain nonlinear systems with unknown measurement sensitivity. A new high gain observer is designed with which the sensitivity function can be tackled by only one dynamic gain and the coupled linear-like controller is fairly simple. By introducing some transformations of the state estimation errors and observer states, and appropriately choosing Lyapunov-Krasovskii functionals, it is proved that the proposed controller can globally stabilize the system.