Time varying attitude control strategies for the Myriade satellites

This paper studies time-varying structures for satellite attitude control systems. The considered satellites are from the Myriade family developed by the French Space Agency (CNES). Analysis of the existing control law and control requirements show that model reference control is suitable provided that the reference model is time-varying. A model reference linear parameter varying (LPV) strategy is thus considered and a synthesis procedure ensuring closed-loop stability and tracking of a time varying model is given. A different time-varying scheme allowing model following is simple adaptive control (SAC). After recalling the stability conditions for this structure, the two control laws are compared and applied to a simulation model of the DEMETER satellite, part of the Myriade program.