Design of an active suspension system for a micro-gravity experiment

The low micro-vibration level tolerated in micro-gravity experimentation makes it necessary to develop an efficient active suspension system between the structure (the artificial satellite) and the platform holding the experiment. The principle adopted by the French National Centre for Space Research (CNES for Centre National d'Etudes Spatiales) makes use of an elastic link and inertial masses, controlled by computer, the role of which is to decrease, using the effect of inertial reaction, the remaining accelerations of the platform and the resonance due to the suppleness of the mechanical link, Taking account of the templates on the desired frequency response of the suspension, the constraints on the useful movement of actuators and the multivariable aspect of the plant, resulting from the geometry of the platform, leads to an augmented plant on which the optimisation uses mu-synthesis and its D-K iteration procedure, An experimental validation has been undertaken on the GAMMA bench developed by the CNES.