Bounded controls, bounded output injection and the global stabilization of nonlinear interconnected systems via measurement feedback

We study the problem of globally stabilizing through measurement feedback the interconnection of uncertain nonlinear systems, consisting of a linear nominal system perturbed by either nonlinear terms or model uncertainties with an upper block-triangular structure. We recover, in a unifying framework, existing results on the global stabilization via state feedback and generalize them into the more appealing perspective of measurement feedback. The basic ingredient in doing this is given by nonlinear (bounded) output injection and nonlinear (bounded) state feedback controllers.