Linear Parameter-varying Anti-windup Control for Active Microgravity Isolation

In this paper a linear parameter-varying (LPV) anti-windup approach is applied to provide anti-windup compensation for adaptive active microgravity vibration isolation. For such systems, anti-windup protection is required because of actuator saturation in response to inertially based forces acting on the isolated platform. For the example presented in the paper, a static anti-windup compensator scheduled based on the measurement of the rack displacement is designed so that it applies a correcting signal only when the control is saturated. The LPV anti-windup scheme is combined with an LPV controller that shifts its focus from a "soft" setting to a "stiff" setting depending on the need for acceleration minimization or relative displacement reduction to prevent bumping. The performance of the overall closed-loop system is demonstrated by simulations. Copyright c °2005 IFAC