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Liado N.,Elecnor Deimos | Ren Y.,York University | Masdemont J.J.,Polytechnic University of Catalonia | Gomez G.,University of Barcelona
Proceedings of the International Astronautical Congress, IAC | Year: 2012

The aim of this paper is to study the capture of small Near Earth Objects (NEOs) into the Sun-Earth L2 using low-thrust propulsion for mining or science purposes. As it is well known, the vicinity of these points is inside a net of dynamical channels suitable for the transport in the Earth-Moon neighborhood, so different final destinations from here could be easily considered. Asteroids with very small mass and not representing a potential hazard are analyzed. An initial pruning of asteroids is made, considering NEOs with stellar magnitude bigger than 28, which are the smallest available, and NEOs close to the Earth orbit with semi-major axis between 0.85-1.15. Due to the difficult determination of their physical properties, two methods to estimate the asteroid masses are conducted. A procedure to find the low-thrust optimization trajectories has been implemented. The initial seed is obtained integrating forward the equations of motion plus its conjugated equations expressed in cartesian coordinates and applying the Pontryagins maximum principle to obtain the optimal control with a switching function for the thrust. To refine the trajectory a 4 order Runge-Kutta shooting method has been used. The objective function in this study is the fuel consumption. Finally, the capable asteroids to get captured by a low-thrust engine have been listed indicating the main parameters. Copyright© (2012) by the International Astronautical Federation.

Llado N.,Elecnor Deimos | Ren Y.,York University | Masdemont J.J.,Institute Destudis Espacials Of Catalonia Ieec | Masdemont J.J.,Polytechnic University of Catalonia | And 2 more authors.
Acta Astronautica | Year: 2014

In this paper we address the feasibility of capturing small Near-Earth Asteroids (NEAs) into the vicinity of the Sun-Earth L2 libration point using a continuous-thrust propulsion system assumed to be attached to the asteroid. The vicinity of this libration point is a gateway to the Earth-Moon neighborhood and using it for capture, or for transit, small NEAs could be interesting for mining or science purposes. Due to limited maneuver capabilities and security concerns, only NEAs with very small mass, and not representing a potential hazard, are analyzed. First, the NEAs are pruned from JPL NEAs (Jet Propulsion Laboratory, 2012) [1] database and their diameter and mass are estimated using two different methods based on physical properties. Then, fuel-optimal continuous-thrust transfer orbits from the original positions of the NEAs to the Sun-Earth L2 libration point are computed. For this trajectory optimization, the initial seeds are generated by means of a global optimization procedure based on a differential evolution algorithm. Next, these initial seeds are refined with a fourth order Runge-Kutta shooting method, and finally we list the candidate NEAs to be captured using a continuous-thrust propulsion system including the key parameters defining their transfer trajectory. © 2013 IAA.

Vasconcelos J.F.,Elecnor Deimos | Rosa P.,Elecnor Deimos | Kerr M.,Elecnor Deimos | Sierra A.L.,Elecnor Deimos | And 2 more authors.
European Space Agency, (Special Publication) ESA SP | Year: 2015

This paper describes the development of a fault detection system for a model scale autonomous aircraft. The considered fault scenario is defined by malfunctions in the elevator, namely bias and stuck-in-place of the surface. The H∞ design methodology is adopted, with an LFT description of the aircraft longitudinal dynamics, that allows for fault detection explicitly synthesized for a wide range of operating airspeeds. The obtained filter is validated in two stages: in a Functional Engineering Simulator (FES), providing preliminary results of the filter performance; and with experimental data, collected in field tests with actual injection of faults in the elevator surface.

Cacciatore F.,Elecnor Deimos | Cichocki F.,Elecnor Deimos
Proceedings of the International Astronautical Congress, IAC | Year: 2013

In the frame of the studies performed for the asteroid sample retrieval mission MarcoPolo-R, special relevance is being given to the analysis and design of the mission phase in which the S/C will fly in close formation with the target body. The motion around an asteroid shows distinct peculiarities due to the dynamical environment encountered. The low mass of the asteroid implies that other perturbations may be large with respect to the body central gravity; the irregular shape of the asteroid, which in some cases can be very far from being a sphere, causes the classical spherical harmonics modelling to lose accuracy; finally, many asteroids, as the old MarcoPolo-R baseline target 1996 FG3, are binary systems, composed by two bodies of comparable size, generating complex gravitational forces on the S/C. The analysis and design of the close formation flying with an asteroid is complicated further by the limited knowledge available of the physical characteristics of the asteroid environment (mass, size, shape, rotation of the primary, secondary mass size and orbit...). The main tasks carried out by Deimos for the proximity phase analysis were aimed at assessing the delta-V cost and feasibility (stability, safety, and operations) of different types of orbit about the asteroid to execute asteroid global characterisation, radio science experiment and local characterisation prior to descent and landing. The proximity flight conditions considered were controlled polar orbits, terminator plane photo-stable orbits, inertial hovering and body fixed hovering. Two guidance modes were defined for the body fixed hovering, based on the use of full asteroid-relative position observables or only on altitude and relative surface velocity data. This latter mode was further optimised to reduce the resulting longitude drift over the hovering duration. In order to take into account both the effect of different orbit reference conditions (for instance, reference asteroid distance or orbital radii) and of the variability of the environment parameters, two main sets of simulations were carried out. In the first set in which nominal environment conditions were used and the orbit reference parameters were varied, while in the second set extensive Monte Carlo runs were used to simulate nominal orbit scenarios in different stochastic realisations of the environment, enforcing physical coherency of each shot.

Cano J.L.,Elecnor Deimos | Bellei G.,Elecnor Deimos | Martin J.,Elecnor Deimos
Proceedings of the International Astronautical Congress, IAC | Year: 2013

Protecting Earth from the threat implied by the Near Earth Objects (NEO) is gaining momentum in recent years. In the last decade a number of mitigation methods have been pushed forward as a possible remedy to that threat, including nuclear blasts, kinetic impactor, gravity tractors and others. Tools are required to evaluate the NEO deflection performances of each of the different methods, coupled with the orbital mechanics associated to the need to transfer to the target orbit and maybe rendezvous with it. The present suite of tools do provide an integral answer to the need of determining if an asteroid is to collide with Earth (NIRAT tool), compute the required object deflection (NEODET tool) and assess the design features of the possible mitigation space missions (RIMISET tool). The tools are presented, their design analyzed as well as the methods and architecture implemented. Results are provided for two asteroids 2011 AG5 (using the orbit determination solution where this asteroid still was a risk object) and 2007 VK184 and the obtained data discussed in comparison to other results. Copyright© (2013) by the International Astronautical Federation.

Fernandez V.,Elecnor Deimos | Montano J.,Elecnor Deimos | Recupero C.,Elecnor Deimos | Kerr M.,Elecnor Deimos | And 3 more authors.
IFAC Proceedings Volumes (IFAC-PapersOnline) | Year: 2015

The RECONFIGURE Functional Engineering Simulator (FES) is a simulation software tool based on the MATLAB™/Simulink™ modeling & simulation environment, specifically designed to support the industrial verification and benchmarking of the Fault Detection and Diagnosis (FDD) and Fault Tolerant Control (FTC) algorithm prototypes designed by the partners of the RECONFIGURE project. The FES includes the benchmark scenarios defined by Airbus for the evaluation of the FDD/FTC designs, namely sensor faults, actuator faults and icing conditions. Although based on a reusable genericpurpose simulation infrastructure layer, the FES has been customized for the verification campaign to be executed with the Airbus benchmark model. Although the development of the FES has not concluded at the time of writing this article, we can describe the software architecture, design and simulation capabilities of this tool within the context of an industrial verification & validation process. © 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.

Bombardelli C.,Technical University of Madrid | Amato D.,Technical University of Madrid | Cano J.L.,Elecnor Deimos
Acta Astronautica | Year: 2016

Based on a hypothetical asteroid impact scenario proposed during the 2015 IAA Planetary Defense Conference (PDC), we study the deflection of fictitious asteroid 2015 PDC starting from ephemeris data provided by the conference organizers. A realistic mission scenario is investigated that makes use of an ion beam shepherd spacecraft as a primary deflection technique. The article deals with the design of a low-thrust rendezvous trajectory to the asteroid, the estimation of the propagated covariance ellipsoid and the outcome of an ion beam slow-push deflection starting from three worst case scenarios (impacts in New Delhi, Dhaka and Tehran). Displacing the impact point towards an extremely low-populated, easy-to-evacuate region, as opposed to full deflection, is found to be a more effective mitigation approach. Mission design, technical and political aspects are discussed. © 2015 IAA.

De Filippis L.,Elecnor Deimos | Kerr M.,Elecnor Deimos | Haya R.,Elecnor Deimos
Astrophysics and Space Science Proceedings | Year: 2016

In this paper a new trajectory generator for the Terminal Area Energy Management phase of a Reusable Launch Vehicle is presented. During this phase the vehicle has to glide at low Mach to reach the point close to the runway where automatic approach and landing starts. The algorithm presented here is based on the concept of Energy Corridor management and it is composed of two main elements: a trajectory propagator and a ground track generator. Imposing a dynamic pressure profile as function of the altitude, a heading path is selected in order to steer the vehicle toward the runway, putting to zero cross and down track errors. © Springer International Publishing Switzerland 2016.

Gonzalez G.,Elecnor Deimos | Perez R.,Elecnor Deimos | Becedas J.,Elecnor Deimos | Latorre M.J.,Elecnor Deimos | Pedrera F.,Elecnor Deimos
2014 26th International Teletraffic Congress, ITC 2014 | Year: 2014

Earth Observation with optical satellites is a key field in the space sector. In the last decade optical satellites technologically evolved to increase the resolution of the images recorded of the Earth surface. These systems acquire massive data from Earth recordings, and traditional data centers present some limitations. Cloud computing can overcome those limitations and increase the flexibility, scalability and on demand use of resources for processing, storage and distribution of geo-data. Such a model based in cloud computing highly depends on the network topology and on the network impairments. In this work we used PlanetLab Europe and PlanetLab Central to obtain realistic models of the network impairments to be implemented in the GEO-Cloud experiment deployed in Fed4FIRE, whose major objective is to value if future internet technologies can improve current operational Earth Observation systems. © 2014 ITC.

Becedas J.,Elecnor Deimos
Proceedings - 2014 8th International Conference on Innovative Mobile and Internet Services in Ubiquitous Computing, IMIS 2014 | Year: 2014

Earth Observation (EO) is considered a key element in the European Research Roadmap and an opportunity market for the next years. However, this field presents some critical challenges to cover the current demand of services: i) there is massive and large-sized data from Earth Observation recordings; ii) On demand storage, processing and distribution of geoinformation generated with the recorded data are required. Conventional infrastructures have the risks of over/under size the infrastructure when big data is used, they are not flexible to cover sudden changes in the demand of services and the access to the information presents large latencies. These aspects limit the use of EO technology for real time use. The use of cloud computing technology can overcome the previously defined limitations. The GEO-Cloud experiment emerged to find viable solutions to provide highly demanding EO services by using future internet technologies. It is a close to reality experiment, part of the FP7 Fed4FIRE project. GEO-Cloud consists of the design, implementation and testing in cloud a complete EO system, from the acquisition of geo-data with a constellation of satellites to its on demand distribution to end users with remote access. This paper presents the GEO-Cloud experiment design, architecture and foreseen research activity. © 2014 IEEE.

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