Development of a filter wheel for VenSpec-H

EnVision, ESA's upcoming Venus orbiter, seeks to comprehensively understand the planet's evolution, building on the success of Venus Express. It will map Venus's interior, surface, and atmosphere with unprecedented detail, enhancing insights into its geological evolution [1]. VenSpec-H – one of the instruments within the VenSpec Suite – is focusing on the atmosphere both below and above the clouds as it will analyze volcanic plumes, as well as complementing surface and subsurface observations [2]. The results are foreseen to support the research teams of BIRA-IASB under Instrument Lead (IL) Dr. Séverine Robert and ETH Zürich under Profs. Paul Tackley and Taras Gerya – Co-ILs of the VenSpec-H Instrument – in understanding commonalities and differences between the planetary evolutions of Venus and Earth [3][4]. VenSpec-H is an optical spectrometer using an echelle grating to diffract uniform light for detailed compositional analysis. A cooled spectrometer section is preceded by a band selection section based on a combination of a filter wheel and a fixed horizontal double stripe filter. <br/> This paper focusses on the development approach of the Filter Wheel Mechanism (FWM) lead by the Swiss Team of VenSpec-H (HSLU, ETH, FHNW, KOEGL Space) and its drive electronics lead by BIRA. It also gives insights in the tests that were performed with a detailed breadboard built within phase B1 of the project.