Anti-windup applied to adaptive rejection of unknown narrow band disturbances

In this paper, a discrete-time anti-windup augmentation scheme is applied to a model of an active suspension system. The model faithfully reproduces the dynamics of an experimental setup available at the Laboratoire d´Automatique de Grenoble and provided by the Hutchinson Research Center. The underlying control system is an adaptive scheme achieving rejection of unknown narrow band disturbances by acting on a piston with the ultimate goal of reducing the resid- ual force on the top of the suspension. Since the piston is subject to magnitude saturation, the control system is prone to windup effects and experiences severe performance loss when large disturbances affect the suspension. The discrete- time anti-windup scheme, consisting in a copy of the plant that augments the controller dynamics, allows to partially recover the unconstrained performance and induces desirable responses for disturbances of different sizes: from very large to very small. Simulation results are reported to illustrate the effectiveness of the anti-windup solution.