Development of algorithms and methodological analyses for the definition of the operation mode of the raman laser spectrometer instrument

Resumen

In situ exploration of Mars, in collaboration with remote analysis of the red planet, is key to understanding its geologic evolution and establishing whether water and life once existed (or still exist) on the Martian surface. The Raman Laser Spectrometer (RLS) instrument, part of the payload of ESA ExoMars mission, will be the first Raman spectrometer ever to be sent on an interplanetary mission. The potential of Raman spectroscopy as a non-invasive or destructive procedure applied to all kinds of materials defines it as a very important technique for all types of materials, minerals or biological analyses. This spectroscopic technique has remained, however, unprecedented in planetary exploration, so it has been traditionally operated with the intervention of a human operator. In this framework, the present thesis intended to evaluate the scientific capabilities of the RLS instrument, with two main objectives. First, the automation of the instrument and the optimization of the spectra acquisition. To do so, it is necessary to define novel algorithmic procedures which provide the instrument with autonomous decision logic in order to optimize the available resources while increasing the quality and quantity of acquired spectra. Second, the data exploitation from the RLS instrument. To accomplish this objective, the effects on the acquired data of the engineering constraints imposed by space operation are considered. Then, different analytical techniques for the analysis of the final spectra acquired by the instrument are studied and applied. This aims at identifying the samples, but also at quantifying their abundance in mixtures, and assessing the capabilities of this kind of techniques. These two objectives are connected and related to the RLS instrument development based on the following logic: first, it is necessary to prepare the RLS instrument for automated operation and spectra acquisition optimization. Then, the operational constraints imposed by the space / rover operation are taken into account and studied to optimize the overall acquisition process. Finally, the data obtained with the RLS instrument (under its operational constraints) are studied with different techniques. This is performed in order to assess and evaluate the possibilities of data exploitation, including statistical analyses, which can be performed due to the particular operational circumstances of RLS: automatic mapping on powdered samples of the instrument