Method and apparatus for satellite torque balancing

A satellite for orbiting the earth in an orbit plane about the earth with a sun based inertial reference system centered at said satellite having mutually perpendicular overturning, windmill and pitch axes, with the windmill axis being along the projection of the sun line in the orbit plane, said overturning axis being in the orbit plane and normal to the windmill axis, and said pitch axis extending perpendicular to said orbit plane, said satellite comprising:

• a main body;
• a solar panel extending from said main body out of the orbit plane in a deployed position with said panel generally facing the sun;
• said panel having proximal and distal ends relative to said main body and said panel in said deployed position being oriented at an angle relative to a line normal to said orbit plane;
• and
• means for mounting said panel to said main body including sun tracking means for rotating said panel relative to said body about a rotation axis parallel to said pitch axis to track the sun and tilting means for rotating said panel about a tilt axis parallel to the overturning axis and adjacent said panel proximal end to variably orient said panel relative to said normal line whereby said panel is tilted to move said distal end toward or away from the sun and the overturning torque acting on said satellite can be minimized by varying the solar pressure and gravity gradient forces acting on said panel.

A method of reducing overturning torque acting upon a satellite in orbit about the earth in an orbit plane, said satellite having a sun based inertial reference system centered at said satellite having mutually perpendicular overturning, windmill and pitch axes, with the windmill axis being along the projection of the sun line in the orbit plane, the overturning axis being in the orbit plane and normal to the windmill axis, and the pitch axis extending perpendicular to the orbit plane, the satellite having a main body and at least one solar panel extending from said main body out of the orbit plane and facing the sun, said panel having proximal and distal ends relative to said main body and said panel being oriented at an angle relative to a line normal to the orbit plane, said method comprising the steps of:

• a) measuring environmental disturbance torque acting on said satellite in orbit;
• b) determining a desired angle of orientation for said panel relative to said normal line to achieve a desired force on said panel to minimize the overturning torque on said satellite;
• and
• c) rotating said panel about a tilt axis parallel to the overturning axis at the proximal end of said panel to achieve said desired angle of orientation.