Composite formation flying strategy for distributed space telescopes with an ultralarge aperture

Abstract. There is increasing demand for space telescopes with ultralarge apertures in the order of 100 to 1000 m for space exploration. It is difficult to expand a space telescope beyond 100 m because of the extensive structural controls that are needed to satisfy optical interference. Large apertures can be achieved using classical formation flying satellites, but it is difficult to achieve suitable relative position and altitude control. Therefore, a novel composite formation flying strategy for distributed space telescopes that provides an ultralarge aperture and ultrahigh accuracy is presented. The proposed strategy combines coarse and fine formations (FFs) provided by support and payload modules (PMs), respectively. The support and PMs are actively connected by noncontact voice coil actuators (VCAs) in each formation satellite. A model and a VCA collision avoidance control approach are also provided for the proposed satellites. The coarse formation is controlled by small thrusters and gives the relative position accuracy in the order of centimeters. The FF is controlled by the VCAs and gives the relative position accuracy in the order of micrometers. The performance is evaluated using simulation studies.