Experimental set-up of a thermal vacuum chamber for thermal model in-house correlation and characterization of the HYPSO hyperspectral imager

Abstract

Space environment with changing temperatures and vacuum can affect the performance of optics instruments onboard satellites. Thermal models and tests are typically done to understand the optics performance within large space projects, but less often in nanosatellites projects. It is even more rarer for an optics payload inside a CubeSat platform, made by a third provider, to do functional tests on their optics during space environment test campaign. In this research, an in-house made vacuum chamber with the possibility to warm up (TVAC) the devices under tests, and wall-through transparency for optics experiments is set-up. In parallel, a thermal model of the HYPerspectral Small satellite for ocean Observation (HYPSO) Hyperspectral Imager (HSI) is developed. The HSI, which is a transmissive grating hyperspectral instrument ranged in the visible to near infrared wavelength, has been tested in TVAC. As thermal control is based on heating the device under test, a new method for fitting the thermal models inside vacuum chambers with only heating capability is proposed. Finally, the TVAC set-up and the thermal model fitting method have been demonstrated to be appropriate to validate the HSI thermal model, and to characterize the optics performance of HSI in vacuum and in the range of temperatures found inside the in-orbit HYPSO-1 CubeSat.