Adaptive Output Feedback Control for a Class of Uncertain Stochastic Nonlinear Systems With Unknown Time-Delays

This paper investigates the problem of output feedback control for a class of stochastic nonlinear systems with time-delays. Using dynamic gain scaling technique, an adaptive update law is introduced to the observer and controller to deal with the unknown parameters. Based on the Lyapunov-Krasovskii functional and stochastic Barbalat's lemma, it is proved that the proposed universal-type adaptive output feedback controller can regulate all the states of the closed-loop system almost surely. A simulation example is presented to illustrate the effectiveness of the proposed design procedure.