Assembly of a large modular optical telescope (ALMOST)

Abstract

Future space telescope programs need to assess in-space robotic assembly of large apertures at GEO and ESL2 to support ever increasing aperture sizes. Since such large apertures will not fit within a fairing, they must rely on robotic assembly/deployment. Proper assessment requires hardware-in-the-loop testing in a representative environment. Developing, testing, and flight qualifying the myriad of technologies needed to perform such a test is complex and expensive using conventional means. Therefore, the objective of the ALMOST program is to develop a methodology for hardware-in-the-loop assessment of in-space robotic assembly of a telescope under micro-gravity conditions in a more cost-effective and risk-tolerant manner. The approach uses SPHERES, currently operating inside ISS, to demonstrate inspace robotic assembly of a telescope that will phase its primary mirror to optical tolerances to compensate for assembly misalignment. Such a demonstration, exploiting the low cost and risk of SPHERES, will dramatically improve the maturity of the guidance, navigation and control algorithms, as well as the mechanisms and concept of operations, needed to properly assess such a capability.