Stabilization of a class of time varying systems with control saturations and measurement noise with application to nonholonomic systems

We study the problem of globally stabilizing through saturated smooth time-varying measurement feedback a class of time-varying systems with measurement noise and uncertainties having an upper triangular structure (feedforward form). We propose a novel step-by step design, based on splitting a n-dimensional system Σ into n one-dimensional systems Σ j, j = 1, . . . , n, finding a smooth time-varying measurement, feedback controller Cj for each system Σj and selecting the parameters of each Cj in such a way that altogether the controllers Cj, j = 1, . . . ,n, give a controller for the overall system σ. We apply these results to a three-dimensional system in chained form with uncertainties and disturbances with finite energy