Three-axis attitude control using combined gravity-gradient and solar pressure

An attitude satellite controller that combines passive gravity-gradient torque with solar pressure torque is proposed for three-axis stabilization of a micro-satellite. A dumbbell satellite configuration is chosen to increase the gravity-gradient torque and a three-axis stabilization is pursued with the help of small solar sails. Solar pressure task is to help the gravity-gradient torque and not to oppose it. The proposed controller is applied to different test cases: first, for satellite stabilization during the tumble motion, due to a nonperfect separation manoeuvre from the launcher last stage; second, the attitude control performances are studied for different eccentric orbits. The results are given in terms of settling time and maximum amplitude oscillations.