On orbit control using gravity gradient effects
Abstract
The possibility of orbit control using gravity gradient (GG) effects without any mass expulsion is discussed. For simplicity, a dumbbell type satellite and circular orbits are mainly considered. It is shown that the GG effects can be applied to convert attitude torques into orbital torques and vice versa. In central gravitational force fields, maximum orbital torques or thrusts are available from the GG force when roll or pitch angle is plus or minus one fourth pi, provided that the attitude angle is null when the dumbbell axis coincides with the local vertical. Such external torques as geomagnetic or solar wind pressure can be utilized to maintain the one fourth pi attitude, and then the orbital torques are available forever. In noncentral gravitational fields, without any external torque, the orbital radii of circular orbits can be increased by controlling the satellite attitude using electric energy. The use of the earth's oblateness effects and the exterior lunar potential is discussed.
 Publication:

Tokyo International Astronautical Federation Congress
 Pub Date:
 September 1980
 Bibcode:
 1980toky.iafcW....M
 Keywords:

 Circular Orbits;
 Gravity Gradient Satellites;
 Satellite Attitude Control;
 Satellite Orbits;
 Angular Momentum;
 Geopotential;
 Gravitational Fields;
 Polar Orbits;
 Solar Wind;
 Torque;
 Astrodynamics