ε-invariant output stabilization: Homogeneous approach and dead zone compensation

This work addresses the stabilization of dynamical systems in presence of uncertain bounded perturbations using ε-invariance theory. Under some assumptions, the problem is reduced to the stabilization of a chain of integrators subject to a perturbation and is treated in two steps. The evaluation of the disturbance and its compensation. Homogeneous observer and control [5], [19] are the tools utilized to achieve a global asymptotic stability and robustness. The result is formally proven and, to validate the theory, it is applied to the control of the telescopic link of a hydraulic actuated industrial crane used in forestry. Experimental results and a comparison with a standard PI controller are presented.