Adaptive Robust Stabilization of a Family of Uncertain Nonlinear Systems by Output Feedback: The Non-polynomial Case

The problem of global state regulation by output feedback is investigated for a family of uncertain nonlinear systems that are bounded by a triangular system with unknown parameters. The bounding system is allowed to depend linearly on the unmeasurable states but nonlinearly on the systems output. Using the idea of universal control, together with the recent advance in nonlinear output feedback design, we develop a non-identifier based output feedback control scheme achieving, in the presence of nonlinear parameterizations, global asymptotic state regulation as well as boundedness of the closed-loop system. This conclusion was first announced in the work (H.Lei et al., 2006). Here, a complete proof is given.