Design, Fertigung und Test eines Entwicklungsmodells zur Untersuchung des optischen Designs des Venus Emissivity Mappers (VEM) unter Verwendung des Raspberry Pi

Kurzfassung

Nowadays, through remote sensing from space, scientists try to learn more about the evolution of Venus, a planet dominated by high pressure and heat. One of the challenges of remote sensing at Venus originates from its thick atmosphere, which prevents the observation of the planetary surface in the visible spectrum. However, missions like Venus Express provided evidence that there are atmospheric windows in the near infrared spectrum of Venus, which allow the observation of the surface thermal emissions and therefore offer the possibility to analyze the surface composition. To use these atmospheric windows more efficiently, the decision has been made to develop a new infrared camera, the Venus Emissivity Mapper VEM, a further development of the VIRTIS instrument. Deriving from this decision, the presented master thesis will create a development model of the infrared camera based on the optic concept of VEM. To verify the optic concept, emissivity measurements with Venus analog samples shall be conducted at the Planetary Emissivity Laboratory of the German Aerospace Center. The samples, consisting of two adjacent materials, one blackbody and one less emitting material, will be observed with the camera in different wavelengths in the near infrared spectrum. By comparing the received signals of both materials, a statement about the ratio of their emissivity can be made. Since most of the camera components, besides the optics, are already space proven, the detector and electronics will be replaced by COTS components, in this case Raspberry Pi products. Additionally, the suitability of the COTS components for scientific applications as well as their possible use as a nanosatellite controller shall be evaluated through vacuum tests. The required steps for this development, starting from the design of the model, proceeding with the search of suitable optic components, ending with the assembly, test phase and evaluation, are described in more detail in this thesis. By evaluation of the taken camera pictures and detection of different emissivity values the optic concept of VEM has been verified. Furthermore, the capabilities of the Raspberry Pi as a possible electronic for scientific instruments could be determined and its suitability for fine vacuum environments was proven. To make a final statement about the use of the Raspberry Pi as a nanosatellite controller, additional qualification tests should be conducted.