Multiple usage thruster mounting configuration

A method of performing at least one of a plurality of operations of a three-axis stabilized spacecraft having roll, pitch, and yaw axes, and having a north face and south face which when on station in orbit generally face north and south, respectively, said method comprising the steps of:

• (a) pivotally mounting on a first support means a first thruster adjacent the north face of the spacecraft such that it is positioned a spaced distance away from the spacecraft in a first direction parallel to the pitch axis and a spaced distance away from the pitch axis in a second direction normal to the pitch axis and for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the first thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the first thrust vector is generally aligned with the center of mass of the spacecraft;
• (b) pivotally mounting a second thruster on a second support means adjacent the south face of the spacecraft such that it is positioned a spaced distance away from the south face in a third direction opposite the first direction and a spaced distance away from the pitch axis in the second direction and for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the second thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the second thrust vector is generally aligned with the center of mass of the spacecraft;
• and
• (c) selectively positioning the direction of the first and second thrusters on said first and second support means, respectively, for performing an operation.

A thruster device attached to a spacecraft having a north face which when on station in orbit about the earth said north face generally faces north and a south face which when on station in orbit about the earth, said south face generally faces south, said thruster device comprising:

• a thruster having a thrust vector;
• a thermal radiator having a generally planar surface attached to and having thermal contact with said thruster, the thrust vector of said thruster being generally parallel to the planar surface of said thermal radiator;
• a support means for mounting said thruster and said thermal radiator adjacent said north face, said thruster and said radiator being positioned a spaced distance in a direction normal to the north face and a spaced distance in a direction tangential to the north face away from the geometric center of the north face;
• and
• gimbal means pivotally mounting said thruster and said thermal radiator on said support means for selectively positioning the thrust vector of said thruster.

A thruster device attached to a spacecraft having a south face which when on station in orbit about the earth said south face generally faces south, said thruster device comprising:

• a thruster having a thrust vector;
• a thermal radiator having a generally planar surface attached to and having thermal contact with said thruster, the thrust vector of said thruster being generally parallel to the planar surface of said thermal radiator;
• a support means for mounting said thruster and said thermal radiator adjacent the south face, said thruster and said thermal radiator being positioned a spaced distance in a direction normal to the south face and a spaced distance in a direction tangential to the south face away from the geometric center of the south face;
• and
• gimbal means pivotally mounting said thruster and said thermal radiator on said support means for selectively positioning the thrust vector of said thruster.

A system for performing at least one operation of a three-axis stabilized spacecraft having roll, pitch, and yaw axes, and having a north face and a south face which when on station in orbit about the earth generally face north and south, respectively, said system comprising:

• first and second thrusters having first and second thrust vectors, respectively;
• first support means for mounting said first thruster adjacent said north face, said first thruster being positioned a spaced distance away from said north face in a first direction parallel to the pitch axis and a spaced distance away from the pitch axis in a second direction normal to the pitch axis;
• second support means for mounting said second thruster adjacent said south face, said second thruster being positioned a spaced distance away from said south face in a third direction opposite the first direction and a spaced distance away from the pitch axis in the second direction;
• and
• gimbal means pivotally mounting said first and second thrusters on said first and second support means, respectively, for selectively positioning the thrust vectors of said first and second thrusters, said gimbal means including:
• a first gimbal for mounting each of said first and second thrusters for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position to a position at which the first and second thrust vectors are directed away from the pitch axis.

A system for performing at least one of a plurality of operations including orbit raising, north-south station keeping, and selective unloading of momentum wheels used for controlling the orientation of a three-axis stabilized spacecraft having roll, pitch, and yaw axes, and having a north face and a south face which when on station in orbit about the earth generally face north and south, respectively, said system comprising:

• first and second thrusters having first and second thrust vectors, respectively;
• first support means for mounting said first thruster adjacent said north face, said first thruster being positioned a spaced distance away from said north face in a first direction parallel to the pitch axis and a spaced distance away from the pitch axis in a second direction normal to the pitch axis;
• second support means for mounting said second thruster adjacent said south face, said second thruster being positioned a spaced distance away from said south face in a third direction opposite the first direction and a spaced distance away from the pitch axis in the second direction;
• and
• gimbal means pivotally mounting said first and second thrusters on said first and second support means, respectively, for selectively postioning the thrust vectors of said first and second thrusters, said gimbal means including a gimbal system including:
• a first gimbal for mounting said first thruster for thruste for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position to a position at which the first thrust vector is directed such that it does not pass through the center of mass;
• and
• a second gimbal for mounting said second thruster for pivotal movement about an axis parallel to the roll axis bewteen a stowed inoperative position to a position at which the second thrust vector is directed such that it does not pass through the center of mass.

A method of performing at least one of a plurality of operations of a three-axis stabilized spacecraft having roll, pitch, and yaw axis, and having a north face and south face which when on station in orbit generally face north and south, respectively, said method comprising the steps of:

• (a) pivotally mounting on a first support means a first thruster adjacent the north face of the spacecraft such that it is positioned a spaced distance away from the spacecraft in a first direction parallel to the pitch axis and a spaced distance away from the pitch axis in a second direction normal to the pitch axis and for pivotal movement about an axis parallel to the roll axis bewteen a stowed inoperative position to a position at which the first thrust vector is directed such that it does not pass through the center of mass;
• (b) pivotally mounting a second thruster on a second support means adjacent the south face of the spacecraft such that it is positioned a spaced distance away from the south face in a third direction opposite the first direction and a spaced distance away from the pitch axis in the second direction and for pivotal movement about an axis parallel to the roll axis bewteen a stowed inoperative position to a position at which the second thrust vector is directed such that it does not pass through the center of mass;
• and
• (c) selectively postioning the direction of the first and second thrusters on said first and second support means, respectively, for performing an operation.