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Tipaldi M.,Compagnia Generale per lo Spazio | Tipaldi M.,University of Sannio | Glielmo L.,University of Sannio
2nd IEEE International Workshop on Metrology for Aerospace, MetroAeroSpace 2015 - Proceedings | Year: 2015

On-board autonomy is becoming a crucial aspect of currently developed and future space projects, especially for deep space exploration missions. In the near future, spacecrafts will be able to receive, process and achieve high-level goals even in an uncertain or dynamically varying context. This paper presents a Markovian based approach in order to model on-board autonomy mechanisms. This approach fits the three layered autonomous space systems architecture and integrates a partially observable non-homogenous Markov model for the decisional layer with a Markov decision process for the operational layer. Autonomous spacecraft reconfigurability is particularly addressed. © 2015 IEEE.

Koukouli M.E.,Aristotle University of Thessaloniki | Clarisse L.,Free University of Colombia | Carboni E.,University of Oxford | Van Gent J.,Belgian Institute for Space Aeronomy | And 7 more authors.
Annals of Geophysics | Year: 2014

The European Space Agency project Satellite Monitoring of Ash and Sulphur Dioxide for the mitigation of Aviation Hazards, was introduced after the eruption of the Icelandic volcano Eyjafjallajökull in the spring of 2010 to facilitate the development of an optimal End­to­End System for Volcanic Ash Plume Monitoring and Prediction. The Eyjafjallajökull plume drifted towards Europe and caused major disruptions of European air traffic for several weeks affecting the everyday life of millions of people. The limitations in volcanic plume monitoring and prediction capabilities gave birth to this observational system which is based on comprehensive satellite­derived ash plume and sulphur dioxide [SO2] level estimates, as well as a widespread validation using supplementary satellite, aircraft and ground­based measurements. Inter­comparison of the volcanic total SO2 column and plume height observed by GOME­2/Metop­A and IASI/Metop­A are shown before, during and after the Eyjafjallajökull 2010 eruptions as well as for the 2011 Grímsvötn eruption. Co­located ground­based Brewer Spectro­photometer data extracted from the World Ozone and Ultraviolet Radiation Data Centre for de Bilt, the Netherlands, are also compared to the different satellite estimates. Promising agreement is found for the two different types of instrument for the SO2 columns with linear regression coefficients ranging around from 0.64 when comparing the different instruments and 0.85 when comparing the two different IASI algorithms. The agreement for the plume height is lower, possibly due to the major differences between the height retrieval part of the GOME2 and IASI algorithms. The comparisons with the Brewer ground­based station in de Bilt, The Netherlands show good qualitative agreement for the peak of the event however stronger eruptive signals are required for a longer quantitative comparison. © 2014, Editrice Compositori s.r.l., All rights reserved.

Tipaldi M.,Compagnia Generale per lo Spazio | Bruenjes B.,Universittsallee 27 29
2014 IEEE International Workshop on Metrology for Aerospace, MetroAeroSpace 2014 - Proceedings | Year: 2014

Spacecraft health monitoring and management systems (also referred to as FDIR (Fault Detection, Isolation and Recovery) systems)) are addressed since the very beginning of any space mission design and play a relevant role in the definition of their reliability, availability and safety objectives. Their primary purposes are the safety of spacecraft/mission life and the improvement of its service availability. In this paper current technical and programmatic FDIR strategies are presented along with their strong connection with the wider concept of on-board autonomy, which is becoming the key-point in the design of new-generation spacecrafts. Recent projects developed at OHB System AG have brought to light some issues in the current FDIR system design approaches. These findings pave the way for innovative solutions, which can support and not rule out conventional industrial practices. © 2014 IEEE.

Monchieri E.,Compagnia Generale per lo Spazio | Hovland S.,European Space Agency | Masi M.,Polytechnic of Milan | Sliepcevich A.,Polytechnic of Milan | And 3 more authors.
62nd International Astronautical Congress 2011, IAC 2011 | Year: 2011

This paper addresses the final results of the "ISRU Architecture and Technology Study", an ESA Study performed by an Italian-Belgian consortium, consisting of Compagnia Generale per lo Spazio (formerly Carlo Gavazzi Space), Politecnico di Milano and Space Applications Services, aimed at assessing the feasibility of producing oxygen in lunar environment extracting it from regolith. The study concentrated its effort on the Carbothermal Reduction process with non-molten phase using Methane. The paper focuses on the results obtained from an experimental test campaign on a process breadboard. The activities have been conducted by Politecnico di Milano, Chemistry, Material and Chemical Engineering Department. Here, the tests were aimed, at first, at understanding the behaviour of the Carbothermal Reduction with Methane when a solid-gas reaction is implemented and, then, at verifying the efficiency, in terms of capability to extract oxygen (via water) from the raw material, of such a process. Extensive preliminary investigations have been performed also in TGA (Thermal Gravimetric Analysis) in order to drive the experimentation on the breadboard. For the tests, two different lunar simulants, the NU-LHT-2M and the JSC-IA, have been used in order to have representative material of both the main lunar regions, Highlands and Maria, and then to be able to estimate the behaviour of the process also with respect to the different lunar soil compositions. The paper addresses also the results of the definition of a Lunar ISRU System based on the results of the testing on the mentioned process. Technology developments identified during the study have been investigated to assess their criticality and to define the conceptual approach to their solution. This activity led to the definition of the requirements for a Lunar ISRU Demonstrator. Particular emphasis is given in the paper to the conceptual design of such a Demonstrator. Here, it has been conceived in order to be compatible with the ESA Lunar Lander currently in Phase B1 of its development. Copyright ©2010 by the International Astronautical Federation. All rights reserved.

Di Nicolantonio W.,Compagnia Generale per lo Spazio | Cazzaniga I.,National Research Council Italy | Cacciari A.,Compagnia Generale per lo Spazio | Bresciani M.,National Research Council Italy | Giardino C.,National Research Council Italy
Journal of Applied Remote Sensing | Year: 2015

The capabilities of different Earth Observation multispectral satellites are employed for detecting and tracking of desert dust coming from North Africa toward the Northern Italy area and for evaluating the impact of Saharan dust deposition in inland waters, such as those of Lake Garda. Absorbing and scattering spectral optical properties of desert aerosol in the atmospheric windows in the ultraviolet, visible-near-infrared, and infrared spectral ranges are exploited in the dust retrieval performed by OMI/Aura, MODIS/Terra-Aqua, and SEVIRI/MSG satellite sensors. Therefore, the direct link between dust deposition and increase in phytoplankton abundance has been assessed retrieving MERIS-based chlorophyll-a (chl-a) concentration for the desert dust events. Estimates of the increased chl-a in the lake have been derived with values in concentration from 30% to 170%. AERONET sun-photometer measurements, gravimetric particulate matter samplings, in situ chl-a concentration and surface temperature are employed to select events and assess the presence of desert dust and recognize a corresponding increase of the phytoplankton abundance in the analyzed inland waters. The improved observational features that will be provided by the next European Sentinels missions, namely Sentinel-2, 3, 4, 5P, together with MTG-I (Imager) and MTG-S (Sounder) will allow better monitoring atmospheric constituents and studying the environmental impacts of desert dust transport. © 2015 Society of Photo-Optical Instrumentation Engineers (SPIE).

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