DESIGN, DEVELOPMENT AND TEST OF THE ATTITUDE CONTROL SUBSYSTEM FOR AN EARTH OBSERVATION MICROSATELLITE

This paper deals with the Attitude Determination And Control Subsystem (ADACS) of the SMART microsatellite. The subsystem architecture is presented in which four operating modes can be identified: attitude acquisition, mission, wheel momentum unloading and wheel failure. The various modes rely on an innovative operating logic based on an integrated use of reaction wheels and magnetic torquers. This allows an effective management of all the mission phases in which the realization of the required control torque is always guaranteed with a limited use of the on board mass and power resources