Laboratory Demonstration of an Active Optics System for High-Resolution Deployable CubeSat

Noah Schwartz; David Pearson; Stephen Todd; Maria Milanova; William Brzozowski; Andy Vick; David Lunney; Donald MacLeod; Steve Greenland; Jean-François Sauvage; Benjamin Gore

arXiv · 1809.09097

Laboratory Demonstration of an Active Optics System for High-Resolution Deployable CubeSat

Noah Schwartz·David Pearson·Stephen Todd·Maria Milanova·William Brzozowski·Andy Vick·David Lunney·Donald MacLeod·Steve Greenland·Jean-François Sauvage·Benjamin Gore

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Abstract

In this paper we present HighRes: a laboratory demonstration of a 3U CubeSat with a deployable primary mirror that has the potential of achieving high-resolution imaging for Earth Observation. The system is based on a Cassegrain telescope with a segmented primary mirror composed of 4 petals that form an effective aperture of 300 mm. The design provides diffraction limited performance over the entire field-of-view and allows for a panchromatic ground-sampling distance of less than 1 m at an altitude of 350 km. The alignment and co-phasing of the mirror segments is performed by focal plane sharpening and is validated through rigorous numerical simulations. The opto-mechanical design of the prototype and its laboratory demonstration are described and measurements from the on-board metrology sensors are presented. This data verifies that the performance of the mirror deployment and manipulation systems is sufficient for co-phasing. In addition, it is shown that the mirrors can be driven to any target position with an accuracy of 25 nm using closed-loop feedback between the mirror motors and the on-board metrology.

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Noah Schwartz, David Pearson, Stephen Todd, Maria Milanova, William Brzozowski, Andy Vick, David Lunney, Donald MacLeod, Steve Greenland, Jean-François Sauvage, Benjamin Gore. 2018-09-24. Laboratory Demonstration of an Active Optics System for High-Resolution Deployable CubeSat. https://arxiv.org/abs/1809.09097

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