Correction of remanent disturbance torque

Abstract

This paper presents a method to remove effects of remanent disturbance torque. For some small satellites, a considerable magnetic dipole moment still remains after degaussing, thus the remanent torque becomes one of the main disturbance torques that limit their pointing accuracy. Firstly, an attitude extended Kalman filter is developed to estimate magnetometer bias. Secondly, a dipole field model is used to evaluate the remanent dipole moment. Thirdly, the initial control dipole moment yielded using the optimal distribution law is distracted by the estimated remanent dipole. Finally, the corrected magnetic control dipole interacts with geomagnetic field to associate a momentum-biased wheel to control attitude of satellite. The simulations show that the present method has removed effects of remanent disturbance torque to some extent and in turn improved three-axis attitude control accuracy