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arXiv · 2105.12483

Active deployable primary mirrors on CubeSat

Noah Schwartz·Maria Milanova·William Brzozowski·Stephen Todd·Zeshan Ali·Lucie Buron·Jean-François-Sauvage·Charlotte Bond·Heather Bruce·Phil Rees·Marc Ferrari·Donald MacLeod
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Abstract

The volume available on small satellites restricts the size of optical apertures to a few centimetres, limiting the Ground-Sampling Distance (GSD) in the visible to typically 3 m at 500 km. We present in this paper the latest development of a laboratory demonstrator of a segmented deployable telescope that will triple the achievable ground resolution and improve photometric capability of CubeSat imagers. Each mirror segment is folded for launch and unfolds in space. We demonstrate through laboratory validation very high deployment repeatability of the mirrors <{\pm}5 {\mu}m. To enable diffraction-limited imaging, segments are controlled in piston, tip, and tilt. This is achieved by an initial coarse alignment of the mirrors followed by a fine phasing step. Finally, we investigate the impact of the thermal environment on high-order wavefront error and the conceptual design of a deployable secondary fitting inside 1U.

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Noah Schwartz, Maria Milanova, William Brzozowski, Stephen Todd, Zeshan Ali, Lucie Buron, Jean-François-Sauvage, Charlotte Bond, Heather Bruce, Phil Rees, Marc Ferrari, Donald MacLeod. 2021-05-26. Active deployable primary mirrors on CubeSat. https://arxiv.org/abs/2105.12483

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