A peaking free output-feedback tracking sliding mode controller based on high-gain observers (HGO) and control activation dwell-time is introduced for a general class of uncertain single-input-single-output (SISO) nonlinear systems. Global or semi-global practical exponential stability with enlarged domains of attraction and significantly improved transient behavior are obtained. A monitoring scheme is also proposed to deal with HGO peaking induced by output exogenous disturbances.
uncertain nonlinear systems; output-feedback; sliding mode control; peaking phenomenon