Attitude determination, control and stabilization of UoSAT-2

Gravity-gradient torques are very weak and are, alone, unable to provide a satisfactory degree of pointing precision and, if undamped, exhibit considerable libration. Thus, passive gravity-gradient torques are augmented on UoSAT-2 by the use of magnetic torques generated through the use of ‘magnetorquer’ coils, which are commutated with the local geomagnetic field vector according to control algorithms implemented by an onboard computer.The attitude dynamics, stabilization procedures, attitude determination procedures and orbital results of UoSAT-2 are described, indicating the expected limits of performance and plans for future work.