EAST WEST ORBIT CONTROL DEVICE BETWEEN NORTH AND SOUTH STATIONARY OPERATIONS OF SPACE FLIGHT BODY

摘要

PURPOSE: To obtain a method for performing the East/West orbit control during the North/Source stationkeeping maneuver of a 3-axis stabilized spacecraft by providing primary and secondary attitude control thruster strings and thrust strings exerting roll, pitch and yaw torques for the spacecraft. CONSTITUTION: A satellite comprises means for actuating the North/South thrusters of thruster strings affecting a perturbation in the attitude to maneuver in the North-South direction, means for defining a dead zone of the East/West orbit velocity, and attitude control means for energizing the primary string thruster to counteract the perturbation, the thruster being oriented so as to cause a change in the West/West orbit velocity. It further comprises means for detecting the orbit velocity change, means for deactivating the primary string thruster in response to the orbit velocity change reaching a limit and for activating the secondary string thruster for exerting a torque on the satellite, and means for causing an oppositely directed change in the East/West orbit velocity.