Synchronized Formation Rotation and Attitude Control of Multiple Free-Flying Spacecraft

Intheobservationslewingoflongbaselineinterferometersformedbymultiplefree-e yingspacecraftinformation, it is required to rotate the entire formation about a given axis and to synchronize individual spacecraft rotation with formation rotation. Using a particle model for spacecraft formation dynamics and a rigid-body model for spacecraft attitude dynamics, control laws are derived for this mode of operation in the absence of a gravitational e eld and disturbances. A simplie ed control law suitablefor implementation isalso obtained. It is shown thatunder mild conditionstheformation alignmenterrordecaystozeroexponentiallywith time. Computersimulationstudies are made for a free-e ying spacecraft triad in a triangular formation. The results show that the developed control laws are effective in synchronized formation rotation.