The Attitude Control System of JAS-2 Satellite

摘要

JAS-2 is the third Japanese amateur radio communication satellite and now planned to launch next August. It is 50 Kg in weight and 50 x 50 x 50 cm in size. By this smallness, the satellite system design is required to save satellite resource severely. The Attitude Control System(ACS) also required to save power and weight. ACS adopted single spin stabilized scheme with magnetic torquing which enables moderate system construction. Attitude measurement is performed by spin type sun-sensor and 2 axes magneto-meter. Two magnetic torquers are equipped. One is aligned to spin axis the other is to orthogonal direction. To eliminate the passive annular nutation damper, magnetic nutation damping scheme is adopted. Due to its small dimension, magnetic interference problem is severe. JAS-2 ACS solves this by using bias correction, digital filtering and tricky control timing. These attitude measurements and control functions are realized by unified 16 bits micro computer and its software. In this paper, this JAS-2 ACS and its ground system are introduced by the stand points of design philosophy and practical technical theme.