TRL-5 cryogenic test campaign for the SAFARI scanning mirror mechanism design adopted for the Phase Delay Mechanism (PDM) of the PRIMA FIRESS instrument

Citation

A. Cournoyer, H. Bourque, É. Carbonneau, P. Gilbert, S. Houle, J.-A. Boulet, I. Silversides, M. Larouche, N. Milaniak, F. Grandmont, D. Naylor, B. Gom, A. Christiansen, and M. Buchan. "TRL-5 cryogenic test campaign for the SAFARI scanning mirror mechanism design adopted for the Phase Delay Mechanism (PDM) of the PRIMA FIRESS instrument". In: SPIE Astronomical Telescopes + Instrumentation, 2026. Maastricht, Netherlands.
Conference Proceedings Abstract submitted

Abstract

ABB Inc. has been involved in the development of cryogenic scanning mirror mechanism technologies for the SPICA mission since 2014 and has been under contract with the Canadian Space Agency from 2019 to 2024 to develop and test at 4 K an Engineering Demonstration Unit (EDU) for TRL-5 demonstration of the high spectral resolution mode of the SpicA FAR-infrared Instrument (SAFARI). Although the ESA/JAXA SPICA mission was cancelled in October 2020, ABB’s cryogenic scanning mirror mechanism design has been adopted for the Phase Delay Mechanism (PDM) of the Far-InfraRed Enhanced Survey Spectrometer (FIRESS) instrument during Phase A of the PRobe far-Infrared Mission for Astrophysics (PRIMA). In this paper, we describe the EDU novel design developed and built at ABB along with its laser metrology sensor and electronic control unit, and the results from the TRL-5 cryogenic test campaign conducted by BSS at the University of Lethbridge are reported, successfully demonstrating the EDU compliance with the challenging cryogenic functional and performance requirements essentially common to both SAFARI and the PDM of the PRIMA FIRESS instrument (namely position stability of roof-top mirrors in step scan mode <10 nm RMS, velocity jitter in constant velocity mode <1% RMS at 85 µm/s, linear stroke >35 mm, error on position feedback laser metrology <10 nm RMS, ultra-low photon leakage level from laser metrology (<1 pW), heat dissipation limited to <1.5 mW). TRL 5 achievement is confirmed through integration of the EDU to a cryogenic far-infrared post-dispersed polarizing Fourier transform spectrometer built and successfully tested by BSS at the University of Lethbridge.