Three-axis magnetic attitude control algorithms for small satellites

Recently there has been a surge of interest in developing new techniques for the attitude control of small satellites using only magnetic actuation. Although the control torque at any instant can only be generated perpendicular to the geomagnetic field vector, such a spacecraft is still controllable if the magnetic field along its orbit is periodic in time. In this paper we present three-axis attitude control algorithms for small satellites using only magnetic torquers and investigate their performance through simulations. These algorithms combine ideas from averaging and linear quadratic regulation. Computer simulations are included to illustrate the effectiveness of the proposed control laws.