Spacecraft momentum management

摘要

Three-axis spacecraft momentum management is performed for a spacecraft traveling along a trajectory, by an actuator including at least one thruster disposed on a single positioning mechanism. As the spacecraft travels along the trajectory, a desired line of thrust undergoes a substantial rotation in inertial space. When the spacecraft is located at a first location on the trajectory, the single positioning mechanism orients the thruster so as to produce a first torque to manage stored momentum in at least one of a first and a second of the three inertial spacecraft axes. When the spacecraft is located at a second location on the trajectory, the single positioning mechanism orients the thruster so as to produce a second torque to manage stored momentum in at least a third of the three inertial spacecraft axes.

主权项

1. A method for managing momentum of a spacecraft traveling along a trajectory, the method comprising:
determining a respective momentum storage error (MSE) in each of three inertial spacecraft axes, said respective MSE comprising a difference, for each axis, between a momentum value actually stored on the spacecraft and a desired momentum value; reducing each respective MSE by producing, with at least one thruster disposed on a single positioning mechanism, a plurality of torques, by:
orienting the thruster, with the single positioning mechanism, so as to produce a first torque that reduces the respective MSE of either or both of a first and a second of the three inertial spacecraft axes when the spacecraft is located at a first location on the trajectory, and,orienting the thruster, with the single positioning mechanism, so as to produce a second torque that reduces the respective MSE of at least a third of the three inertial spacecraft axes when the spacecraft is located at a second location on the trajectory; wherein,the single positioning mechanism is configured to orient the thruster so as to simultaneously (i) accelerate the spacecraft along a line of thrust and (ii) produce a torque around at least one of two axes substantially orthogonal to the nominal thrust vector; andas the spacecraft travels along the trajectory, a desired line of thrust undergoes a substantial rotation in inertial space.