Magnetic attitude control for synchronous satellites

Techniques using active magnetic coils have been studied for the attitude control of long-life vehicles in synchronous equatorial orbits, Analysis and computer simulation were followed by laboratory tests to investigate various control laws and methods of damping. The results demonstrated that three-axis control is feasible using a hybrid system of coils for torque about two axes and jets or an inertia wheel for the third axis. The use of an on-off controller with lead-lag compensation led to very small impulse capability resulting in efficient limit-cycle performance and high accuracy.