The research on electrodynamic tethers (EDT) has been a fruitful field sinceudthe 70’s. This technology has been developed thanks to both theoretical studiesudand demonstration missions. During this period, several technical issues wereudidentified and overcome. Among those problems, two of them would entail anudimportant reduction in the operational capabilities of these devices. First, theudefficient collection of electrons in rarefied plasma and, second, the dynamicudinstability of EDTs in inclined orbits. The bare tether concept represents theudsurmounting of the current scarcity in low density plasma. This method ofudinteraction with the ionosphere promises to considerably increase the intensityudalong the tether. In turn, the dynamic instability could be avoided by balancingudthe EDT, as it has been proposed with the Self Balanced ElectrodynamicudTether (SBET) concept. The purpose of this thesis is to prove the suitability ofudboth concepts working together in several space applications: from mitigationudof the space debris to capture in a Jovian orbit.udThe computation of the electron collection by a bare tether is faced in firstudplace. The semi-analytical method derived in this work allows to calculate accuratelyudand efficiently the intensity which flows along a tether working on theudOML (orbit-motion-limited) regime. Then, an energy study is derived, whereudthe EDT is analyzed as an energy converter. This approach provides a linkudamong the different aspects of the problem, from both electrical and dynamicaludpoints of view. All the previous considerations will lead to the introductionudof control laws based on the SBET concept, enhancing its capabilities. Theseudanalysis will be tested in a couple of particular scenarios of interest.udMitigation of space debris has become an issue of first concern for all theudinstitutions involved in space operations. In this context, EDTs have beenudpointed out as a suitable and economical technology to de-orbit spacecrafts atudthe end of their operational life. Throughout this dissertation the numericaludsimulation of different de-orbiting missions by means of EDTs will allow toudhighlight its main characteristics and recognize the different parameters whichudare involved. The simulations will assess the suitability of electrodynamicudtethers to perform these kind of mission.udOn the other hand, one of the foremost objectives within Solar Systemudexploration is Jupiter, its moons and their surroundings. Due to the presenceudof magnetic field and plasma environment, this scenario turns out to beudparticularly appropriate for the utilization of EDTs. These devices would beudcapable to generate power and thrust without propellant consumption. Orbitaludmaneuvers and power generation will be therefore ensured. In this work,udthe possibility of using self balanced bare electrodynamic tethers to performuda capture in Jovian orbit is analyzed. In addition, within this research, theudanalysis of the dynamics of a tether in the neighborhoods of a Lagrangianudpoint results to be interesting since it models the motion of a space systemudnear a Jupiter’s moon. That would allow to study the establishment of a permanentudobservatory for scientific observation in Jovian orbit. The analysis ofudthe restricted three body problem is developed without taking into account theudelectrodynamic perturbation, leaving the inclusion of this feature for furtherudresearch. Finally, within the frame of this dissertation, an additional analysisudis presented. The study is related to the possible role of EDT in geodetic missions.udThe work gathered here describes an initial analysis of the capabilitiesudof a tethered system to recover gravitational signals by means of measuring itsudtension.ud
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