Robust adaptive regulation of discrete time nonlinear systems with arbitrary nonlinearities

This note develops a new recursive estimator with a dead zone. By using the estimator, a robust adaptive regulator for a class of simple discrete time nonlinear systems with bounded disturbance is presented. A global stability result of the closed-loop system is obtained through Lyapunov analysis without assuming any growth conditions on the nonlinearities. The regulation performance is also presented through a simulation example.