The Design of the OPAL Attitude Control System

OPAL's attitude is controlled by using two pairs of magnetic coils and a three axis magnetometer. One pair of coils is mounted on the side panel where the picosatellite launch window is located. The other pair is mounted on the bottom panel. The primary requirements of the attitude control system are to decease spin of the satellite with respect to its body axis to minimize disturbances during picosatellite launch, and to spin up the satellite once the picosatellite is launched to meet thermal requirements. To meet these requirements the "minus Bdot" control law was used. This paper will describe the design and testing of the OPAL attitude control system.