Robust tracking control for a class of uncertain nonlinear systems

We investigate the global robust tracking problem via output feedback for a class of nonlinear systems with dynamic uncertainties and nonvanishing nonlinear disturbances. The dead zone technique is applied to overcome the bursting phenomenon. A recursive design scheme is presented with the help of backstepping method. It is shown that under some assumptions, the tracking error can be guaranteed asymptotic to the interval [-∈, ∈] ⊂ R with arbitrary prescribed ∈ > 0 after a finite time, while keeping all the signals of the resulting closed-loop systems bounded.