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Passive and Active Control of Solar Array Vibrations Induced by the Change of Thermal Input


 The behaviour of large and flexible space structures, if compared with compact and rigid ones, is largely influenced by thermal loads in orbit. In this paper, the control of a spacecraft attitude disturbance, induced by cyclic temperature variations in the solar array substructures, is investigated. Both passive and active control techniques have been considered to reduce the vibration amplitude. A new version of tension mechansim powered by constant force springs is compared with a previous mechanism from the point of view of induced disturbances in the satellite attitude. A new algorithm for closed-loop pole placement of a symmetric, second order dynamical system is presented, and results of closed-loop numerical simulations are shown. Finally, experimental investigations are discussed and the relative results are presented.