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Covello F.,ASI Agenzia Spaziale Italiana
Advances in Space Research | Year: 2012

One of the main challenge in the design of an active removal system for space debris is the high ΔV required both to approach space debris lying in different orbits and to de-orbit/re-orbit them. Indeed if the system does not target a number of objects during its lifetime the cost of the removal will be far too high to be considered as the basis of an economically viable business case. Using a classical chemical propulsion (CP) system, the ΔV is limited by the mass of propellant that the system can carry. This limitation is greatly reduced if electrical propulsion is considered. Electrical propulsion (EP) systems are indeed characterized by low propellant mass requirements, however this comes at the cost of higher electrical power and, typically, higher complexity and mass of the power supply system. Because of this, the use of EP systems has been, therefore, primarily limited to station keeping maneuvers. However in the recent past, the success of missions using EP as primary propulsion (e.g. GOCE, SMART-1, Artemis, Deep Spcae1, Hayabusa) makes this technology a suitable candidate for providing propulsion for an active debris removal system. This study case will provide the analysis of the possible application of electrical propulsion systems in such a context, presenting a number of possible mission profiles. This paper will start with the description of possible mission concepts and the assessment of the EP technology, comparing near-term propulsion options, that best fits the mission. A more detailed analysis follows with the relevant trade-off to define the characteristics of the final system and its size in terms of mass and power required. A survey of available space qualified EP systems will be performed with the selection of the best candidates to be used and/or developed for an active debris removal system. The results of a similar analysis performed for a classical CP system are then presented and the two options are compared in terms of total cost of the mission. The output of this study case shows that the EP is a suitable solution in a very demanding ΔV system such as active debris removal satellites and that the current technology is sufficiently mature to be used in the very near future. © 2012 COSPAR. Published by Elsevier Ltd. All rights reserved. Source


Castronuovon M.M.,ASI Agenzia Spaziale Italiana
Acta Astronautica | Year: 2011

The active removal of five to ten large objects per year from the low Earth orbit (LEO) region is the only way to prevent the debris collisions from cascading. Among the three orbital regions near the Earth where most catastrophic collisions are predicted to occur, the one corresponding to a sun-synchronous condition is considered the most relevant. Forty-one large rocket bodies orbiting in this belt have been identified as the priority targets for removal. As part of a more comprehensive system engineering solution, a space mission dedicated to the de-orbiting of five rocket bodies per year from this orbital regime has been designed. The selected concept of operations envisages the launch of a satellite carrying a number of de-orbiting devices, such as solid propellant kits. The satellite performs a rendezvous with an identified object and mates with it by means of a robotic arm. A de-orbiting device is attached to the object by means of a second robotic arm, the object is released and the device is activated. The spacecraft travels then to the next target. The present paper shows that an active debris removal mission capable of de-orbiting 35 large objects in 7 years is technically feasible, and the resulting propellant mass budget is compatible with many existing platforms. Copyright © 2011 Published by Elsevier Ltd. Source


Patent
University of Cagliari, Centro Of Ricerca and A.S.I. Agenzia Spaziale Italiana | Date: 2012-07-24

A process for the production of useful materials to sustain manned space missions on Mars, as well as the kit of materials and apparatus for implementing the same, is described. Said process uses as raw feedstock only natural resources available in-situ, namely Mars atmosphere and regolith. The kit allows to implement the process of the invention by providing all materials and apparatus that will be used on the Martian soil.


Patent
A.S.I. Agenzia Spaziale Italiana and University of Cagliari | Date: 2011-07-28

A process for manufacturing physical assets for civil and/or industrial facilities on Moon, Mars and/or asteroid, as well as the kit of materials and apparatus for implementing the same. Such a kit allows in fact to implement the process of the invention by providing all materials and apparatus that will be applied on Moon, Mars and/or asteroid, thus advantageously and significantly reducing, either the costs and the volume and bulk of the materials. The process comprises the steps of enriching the regolite present in the soil in ilmenite or in iron oxides, then mixing it with aluminum powder and sending the resulting mixture to a reaction chamber for the obtention of constructive elements.


Covello F.,ASI Agenzia Spaziale Italiana | Scopa T.,ASI Agenzia Spaziale Italiana | Serva S.,Ministry of Defense | Caltagirone F.,ASI Agenzia Spaziale Italiana | And 3 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

COSMO-SkyMed Second Generation (CSG) system has been conceived, according to Italian Space Agency (ASI) and Italian Ministry of Defence (It-MoD) requirements, at the twofold objective of ensuring operational continuity to the current constellation (COSMO-SkyMed - CSK), while improving functionality and performances. It is an "end-to-end" Italian Earth Observation Dual-Use (Civilian and Defence) Space System with Synthetic Aperture Radar (SAR) operating in X-Band. CSG mission planning purpose is to fully employ the system resources, shared between partners with very different needs, producing a mission plan that satisfies the higher priority requests and optimizes the overall plan with the remaining requests according to the users programming rights consumption. CSG Mission Planning tool provides new performances in terms of adaptability and flexibility of the planning and scheduling algorithms conceived to select and synchronize data acquisition and downloading activities. CSG planning and scheduling problem is characterized by a large size of research space and a particular structure of technical and managerial constraints that has led to the implementation of innovative design of the planning algorithms based on both priority criteria and saturation of system resources. This approach envisages two scheduling strategies: the rank-based and the optimization-based. The former strategy is firstly applied to the most important request categories, with an associated rank value or priority level; the latter is subsequently applied to the unranked or lower priority requests. This is an iterative dynamic process of finding optimal solutions able to better answer the demanding requirements coming from the needs of heterogeneous users. © 2014 SPIE. Source

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