DYNAMICS OF CONFIGURATION CHANGES OF CLOSE FORMATIONS AT THE SUN-EARTH LIBRATION POINT

Here the formation flying strategy for multi-spacecraft astrophysics missions is analysed. Around the Sun Earth libration points the formation flying problem can be treated as a force-free mode, provided the spatial separation of the spacecraft is not too large. We focus this work on a two-spacecraft formation. A typical application for which a system is an x-ray telescope, in which the mirror and the detector are implemented on different spacecraft. Maneuvering capability is normally implemented on the detector due to its typically lower mass. The detector is thus the chaser spacecraft. Here two types of manoeuvres are considered: type1 slews, in which the chasing spacecraft flies on a circular arc around the main spacecraft to maintain a constant distance during the slew, and type-2 slews, in which the chaser flies along the straight line that connects the initial and final positions. Type-2 slews represent the best-economy solution, but do not allow to maintain a constant distance.