The Deformable Mirror Demonstration Mission (DeMi) CubeSat: optomechanical design validation and laboratory calibration

Gregory Allan; Ewan S. Douglas; Derek Barnes; Mark Egan; Gabor Furesz; Warren Grunwald; Jennifer Gubner; Christian Haughwout; Bobby G. Holden; Paula do Vale Pereira; Abigail J. Stein; Kerri L. Cahoy

arXiv · 1807.02649

The Deformable Mirror Demonstration Mission (DeMi) CubeSat: optomechanical design validation and laboratory calibration

Gregory Allan·Ewan S. Douglas·Derek Barnes·Mark Egan·Gabor Furesz·Warren Grunwald·Jennifer Gubner·Christian Haughwout·Bobby G. Holden·Paula do Vale Pereira·Abigail J. Stein·Kerri L. Cahoy

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Abstract

Coronagraphs on future space telescopes will require precise wavefront correction to detect Earth-like exoplanets near their host stars. High-actuator count microelectromechanical system (MEMS) deformable mirrors provide wavefront control with low size, weight, and power. The Deformable Mirror Demonstration Mission (DeMi) payload will demonstrate a 140 actuator MEMS deformable mirror (DM) with \SI{5.5}{\micro\meter} maximum stroke. We present the flight optomechanical design, lab tests of the flight wavefront sensor and wavefront reconstructor, and simulations of closed-loop control of wavefront aberrations. We also present the compact flight DM controller, capable of driving up to 192 actuator channels at 0-250V with 14-bit resolution. Two embedded Raspberry Pi 3 compute modules are used for task management and wavefront reconstruction. The spacecraft is a 6U CubeSat (30 cm x 20 cm x 10 cm) and launch is planned for 2019.

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Gregory Allan, Ewan S. Douglas, Derek Barnes, Mark Egan, Gabor Furesz, Warren Grunwald, Jennifer Gubner, Christian Haughwout, Bobby G. Holden, Paula do Vale Pereira, Abigail J. Stein, Kerri L. Cahoy. 2018-07-07. The Deformable Mirror Demonstration Mission (DeMi) CubeSat: optomechanical design validation and laboratory calibration. https://arxiv.org/abs/1807.02649

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