SPACEBUS 4000: FROM EARTH SENSORS TO 3-AXIS STAR TRACKERS CONTROL OF TELECOMMUNICATION SPACECRAFT

摘要

Spacebus 4000 telecommunication spacecraft are now operated without Earth sensor. It took a long way to achieve this configuration. It was only possible thanks to the high records of Star Trackers and their careful and step by step introduction in the AOCS control loop. The paper will retrace the main milestones of the STR introduction on Spacebus 4000 that finally ended with the earth sensor removal. Flight records showing the great superiority of stellar pointing versus direct earth pointing will be provided.