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Unterkirnach, Germany

Mehlem K.,Sonnemveg 22 | Wiegand A.,Astos Solutions GmbH
2010 Asia-Pacific Symposium on Electromagnetic Compatibility, APEMC 2010

Stringent magnetostatic cleanliness programs are required for interplanetary scientific spacecraft like Ulysses, Cluster, Double Star, Cassini, Rosetta many others, which carry sensitive magnetometers operating in a low interplanetary field environment. Due to the strong Earth field and the limited precision of coil facilities it is impossible to verify the stringent magnetic cleanliness specification (typically 0.1-1 nT) by direct measurements at the specification point. The paper describes the use of Multiple Dipole Models which generates precise far-field estimates. The model parameters of the so-called MDMs are identified on the basis of near-field measurements. The method, developed by K. Mehlem in the early eighties, is implemented in the GAMAG software. The paper mentions some historical aspects and describes in more detail the NLP solver used, as well as some inherent identification problems which are due to data sparsity and to parameter constraints. The characteristics of the software are presented, in particular the efficient combination of deterministic and stochastic solver strategies, the statistical refinement of far-field estimates, the capabilities to optimize compensation MDMs (magnets or coils) for multiple far-field points, and finally the ease of use. © 2010 IEEE. Source

Sippel M.,Launcher | Van Foreest A.,Launcher | Bauer C.,Launcher | Cremaschi F.,Astos Solutions GmbH
17th AIAA International Space Planes and Hypersonic Systems and Technologies Conference 2011

DLR's launcher systems analysis division has proposed a visionary, extremely fast passenger transportation concept reaching the edges of space based on rocket propulsion. The paper describes the recent technical progress achieved in the SpaceLiner configuration. The revolutionary ultrafast transport is now under investigation in the EU-funded study FAST20XX (Future high-Altitude high-Speed Transport 20XX) set off in December 2009. The focus of the paper is on all system aspects of the preliminary design including its flight performance impact on design choices. A major new result is the replacement of the original skipping trajectory by a smooth glide obtained in system optimizations. © 2011 by DLR-SART. Source

Scheuerpflug F.,German Aerospace Center | Kallenbach A.,TU Munich | Cremaschi F.,Astos Solutions GmbH
Journal of Spacecraft and Rockets

The mission architecture of SHEFEX II features a two-stage solid propellant sounding rocket vehicle on a suppressed trajectory, which is induced by a cold gas pointing maneuver of the vehicle before second stage ignition. The impact point is subject to a 3-? dispersion of roughly?110 kmin downrange and-90 kmin crossrange, which makes a recovery of the vehicle particularly difficult, as the whole impact area is located off shore and the vehicle needs to be recovered by ship. As the major part to dispersion is contributed during the atmospheric ascent of the vehicle, a control algorithm is developed that considers the actual deviation from the nominal trajectory after atmospheric exit and recommends a vehicle pointing that corrects for this deviation. The analytic control algorithm is found by linear/quadratic approximation of the impact point sensitivity towards the deviations after atmospheric exit and to the pointing angles. The effectiveness of the algorithm is tested by implementing it in a full six-degree-offreedom simulation and applying dispersion factors in a Monte Carlo simulation. The result is a reduction of the impact point dispersion area by about 78%. Copyright © 2012 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. Source

Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: AAT.2008.6.2.1.;AAT.2008.6.2.2. | Award Amount: 7.23M | Year: 2009

The current project aims at the investigation and development of technologies and steps necessary for approaches to conquer the grey zone between aeronautics and space in Europe, and thus to set the foundation of a new paradigm for transportation in the long term. The underlying concepts considered are a) a European space plane based on an airplane launch approach to advance European know how in this area, based essentially on a ballistic flight experience using hybrid propulsion, and b) the same space plane envisioned to evolve into suborbital point-to-point long-distance transport in very short times by using high-energy propulsion. An alternative, vertically starting two-stage rocket space vehicle system concept is used to identify technologies required for suborbital ultra-fast transportation. The concepts will be addressed separately and in relation to each other as well as with those considered in other EC projects, exploiting similarities and synergies wherever possible. The concepts can be classified with near term and very long term realisation capabilities, and will be evaluated according to the maturity of underlying technology, inherent risk, sustained operations, and cost. All concepts and technologies will be considered with respect to environmental issues. Some activities concern the leagal issues and those of suitable space ports. Due to the recent agreement with Virgin Galactic, it is quite natural to consider the ESRANGE facility in Sweden an excellent candidate for a starting place of experimental high-altitude high-speed flights.

Agency: Cordis | Branch: FP7 | Program: CP | Phase: SPA-2007-2.2-01;SPA-2007-2.2-02 | Award Amount: 5.36M | Year: 2008

The main objective of the HiPER project is to initiate technological and programmatic consolidation in the development of innovative electric propulsion technologies (and of the related power generation) to fulfill future European space transportation needs. The objective will be pursued by conceiving and substantiating a long term vision for European space transportation and exploration, considering realistic developments in the state-of-the-art, and by performing basic research and proof-of-concept experiments on the key technologies identified by such a vision.

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