TY - CHAP A1 - Braun, Carsten A1 - Boucke, Alexander A1 - Ballmann, Josef T1 - Numerical study of the influence of dynamic pressure and deflected ailerons on the deformation of a high speed wing model T2 - High performance computing in science and engineering '04. Transactions of the High Performance Computing Center Stuttgart (HLRS) 2004 / Eds.: Egon Krause ... Y1 - 2005 SN - 3-540-22943-4 SP - 225 EP - 236 PB - Springer CY - Berlin ER - TY - CHAP A1 - Plescher, Engelbert A1 - Mathiak, Gerhard A1 - Willnecker, Rainer T1 - Technical aspects of liquid diffusion model experiments T2 - 55th International Astronautical Congress : October 4 - 8, 2004, Vancouver, Canada / International Astronautical Federation. Bd. 8. IAC-04-J.5.04 Y1 - 2005 SP - 5019 EP - 5025 PB - International Astronautical Federation CY - Paris ER - TY - JOUR A1 - Mathiak, Gerhard A1 - Plescher, Engelbert A1 - Willnecker, Rainer T1 - Liquid metal diffusion experiments in microgravity - Vibrational effects JF - Measurement science and technology Y1 - 2005 U6 - http://dx.doi.org/10.1088/0957-0233/16/2/003 SN - 0957-0233 VL - Vol. 16 IS - No. 2 SP - 336 ER - TY - JOUR A1 - Mathiak, Gerhard A1 - Willnecker, Rainer A1 - Plescher, Engelbert T1 - Vibrational effects on diffusion experiments JF - Microgravity science and technology : international journal for microgravity research and applications Y1 - 2005 SN - 0938-0108 VL - Vol. 15 IS - No. 1 SP - 295 EP - 300 ER - TY - CHAP A1 - Dachwald, Bernd T1 - Global optimization of low-thrust space missions using evolutionary neurocontrol T2 - Proceedings of the international workshop on global optimization N2 - Low-thrust space propulsion systems enable flexible high-energy deep space missions, but the design and optimization of the interplanetary transfer trajectory is usually difficult. It involves much experience and expert knowledge because the convergence behavior of traditional local trajectory optimization methods depends strongly on an adequate initial guess. Within this extended abstract, evolutionary neurocontrol, a method that fuses artificial neural networks and evolutionary algorithms, is proposed as a smart global method for low-thrust trajectory optimization. It does not require an initial guess. The implementation of evolutionary neurocontrol is detailed and its performance is shown for an exemplary mission. KW - Evolutionary Neurocontrol KW - Spacecraft Trajectory Optimization KW - Low-Thrust Propulsion Y1 - 2005 SP - 85 EP - 90 ER - TY - CHAP A1 - Dachwald, Bernd A1 - Baturkin, Volodymyr A1 - Coverstone, Victoria A1 - Diedrich, Ben A1 - Garbe, Gregory A1 - Görlich, Marianne A1 - Leipold, Manfred A1 - Lura, Franz A1 - Macdonald, Malcolm A1 - McInnes, Colin A1 - Mengali, Giovanni A1 - Quarta, Alessandro A1 - Rios-Reyes, Leonel A1 - Scheeres, Daniel J. A1 - Seboldt, Wolfgang A1 - Wie, Bong T1 - Potential effects of optical solar sail degredation on trajectory design T2 - AAS/AIAA Astrodynamics Specialist N2 - The optical properties of the thin metalized polymer films that are projected for solar sails are assumed to be affected by the erosive effects of the space environment. Their degradation behavior in the real space environment, however, is to a considerable degree indefinite, because initial ground test results are controversial and relevant inspace tests have not been made so far. The standard optical solar sail models that are currently used for trajectory design do not take optical degradation into account, hence its potential effects on trajectory design have not been investigated so far. Nevertheless, optical degradation is important for high-fidelity solar sail mission design, because it decreases both the magnitude of the solar radiation pressure force acting on the sail and also the sail control authority. Therefore, we propose a simple parametric optical solar sail degradation model that describes the variation of the sail film’s optical coefficients with time, depending on the sail film’s environmental history, i.e., the radiation dose. The primary intention of our model is not to describe the exact behavior of specific film-coating combinations in the real space environment, but to provide a more general parametric framework for describing the general optical degradation behavior of solar sails. Using our model, the effects of different optical degradation behaviors on trajectory design are investigated for various exemplary missions. Y1 - 2005 N1 - 2005 AAS/AIAA Astrodynamics Specialist Conference, 7-11.08.2005. Lake Tahoe, California https://www.space-flight.org/AAS_meetings/2005_astro/2005_astro.html SP - 1 EP - 23 ER - TY - JOUR A1 - Dachwald, Bernd T1 - Optimization of very-low-thrust trajectories using evolutionary neurocontrol JF - Acta Astronautica N2 - Searching optimal interplanetary trajectories for low-thrust spacecraft is usually a difficult and time-consuming task that involves much experience and expert knowledge in astrodynamics and optimal control theory. This is because the convergence behavior of traditional local optimizers, which are based on numerical optimal control methods, depends on an adequate initial guess, which is often hard to find, especially for very-low-thrust trajectories that necessitate many revolutions around the sun. The obtained solutions are typically close to the initial guess that is rarely close to the (unknown) global optimum. Within this paper, trajectory optimization problems are attacked from the perspective of artificial intelligence and machine learning. Inspired by natural archetypes, a smart global method for low-thrust trajectory optimization is proposed that fuses artificial neural networks and evolutionary algorithms into so-called evolutionary neurocontrollers. This novel method runs without an initial guess and does not require the attendance of an expert in astrodynamics and optimal control theory. This paper details how evolutionary neurocontrol works and how it could be implemented. The performance of the method is assessed for three different interplanetary missions with a thrust to mass ratio <0.15mN/kg (solar sail and nuclear electric). Y1 - 2005 SN - 1879-2030 VL - 57 IS - 2-8 SP - 175 EP - 185 PB - Elsevier CY - Amsterdam [u.a.] ER - TY - BOOK A1 - Esch, Thomas T1 - Dynamik der Fahrzeuge : Längsdynamik. - 5. Aufl., [Umdruck]. - (Angewandte Thermodynamik und Verbrennungstechnik) Y1 - 2006 PB - Fachhochschule Aachen, Lehr- und Forschungsgebiet Thermodynamik und Verbrennungstechnik CY - Aachen ER - TY - BOOK A1 - Esch, Thomas T1 - Experimentelle Untersuchungen an Verbrennungsmotoren. - 8. Aufl., [Umdruck]. - (Angewandte Thermodynamik und Verbrennungstechnik) Y1 - 2006 PB - Fachhochschule Aachen, Lehr- und Forschungsgebiet Thermodynamik und Verbrennungstechnik CY - Aachen ER - TY - JOUR A1 - Dachwald, Bernd A1 - Seboldt, W. A1 - Richter, L. T1 - Multiple rendezvous and sample return missions to near-Earth objects using solar sailcraft / Dachwald, B. ; Seboldt, W. ; Richter, L. JF - Acta Astronautica. 59 (2006), H. 8-11 Y1 - 2006 SN - 0094-5765 N1 - International Conference on Low Cost Planetary Missions <5, 2003, Noordwijk> ; Selected Proceedings SP - 768 EP - 776 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Mengali, Giovanni A1 - Quarta, Alessandrao A. A1 - Macdonald, Malcolm T1 - Parametric Model and Optimal Control of Solar Sails with Optical Degradation JF - Journal of guidance, control, and dynamics. 29 (2006), H. 5 Y1 - 2006 SN - 0162-3192 N1 - 2. ISSN: 0731-5090 SP - 1170 EP - 1178 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Kahle, Ralph A1 - Wie, Bong T1 - Solar Sailing Kinetic Energy Impactor (KEI) Mission Design Tradeoffs for Impacting and Deflecting Asteroid 99942 Apophis JF - AIAA Guidance, Navigation, and Control Conference & Exhibit - AIAA Atmospheric Flight Mechanics Conference & Exhibit - AIAA Modeling and Simulation Technologies Conference & Exhibit - AIAA/AAS Astrodynamics Specialist Conference & Exhibit : [21 - 24 August 2006, Keystone, Colorado ; papers]. - (AIAA meeting papers on disc ; [11.]2006,19-20 ) Y1 - 2006 SN - 1-56347-802-1 N1 - American Institute of Aeronautics and Astronautics ; American Astronautical Society ; AIAA/AAS Astrodynamics Specialist Conference & Exhibit <2006, Keystone, Colo.> ; AIAA paper number: AIAA-2006-6178 SP - 1 EP - 20 PB - American Institute of Aeronautics and Astronautics CY - Reston, Va. ER - TY - JOUR A1 - Dachwald, Bernd A1 - Ohndorf, A. A1 - Wie, Bong T1 - Solar Sail Trajectory Optimization for the Solar Polar Imager (SPI) Mission JF - AIAA Guidance, Navigation, and Control Conference & Exhibit - AIAA Atmospheric Flight Mechanics Conference & Exhibit - AIAA Modeling and Simulation Technologies Conference & Exhibit - AIAA/AAS Astrodynamics Specialist Conference & Exhibit : [21 - 24 August 2006, Keystone, Colorado ; papers]. - (AIAA meeting papers on disc ; [11.]2006,19-20 ) Y1 - 2006 SN - 1-56347-802-1 N1 - American Institute of Aeronautics and Astronautics ; American Astronautical Society ; AIAA/AAS Astrodynamics Specialist Conference & Exhibit <2006, Keystone, Colo.> ; AIAA paper number: AIAA-2006-6177 PB - American Institute of Aeronautics and Astronautics CY - Reston, Va. ER - TY - JOUR A1 - Dachwald, Bernd A1 - Carnelli, I. A1 - Vasile, M. T1 - Low-Thrust Gravity Assist Trajectory Optimization Using Evolutionary Neurocontrollers / I. Carnelli ; B. Dachwald ; M. Vasile ... JF - Astrodynamics 2005 : proceedings of the AAS/AIAA astrodynamics conference held August 7 - 11, 2005, South Lake Tahoe, California / ed. by Bobby G. Williams. - Pt. 3. - (Advances in the astronautical sciences ; 123,3) Y1 - 2006 SN - 0-87703-527-X N1 - Astrodynamics Conference <2005, South Lake Tahoe, Calif.> ; American Astronautical Society ; Number: AAS-05-374 SP - 1911 EP - 1928 PB - Univelt CY - San Diego, Calif. ER - TY - JOUR A1 - Dachwald, Bernd A1 - Baturkin, Volodymyr A1 - Coverstone, Victoria L. A1 - Dietrich, Benjamin A1 - Garbe, Gregory P. A1 - Görlich, Marianne A1 - Leipold, Manfred A1 - Lura, Franz A1 - Macdonald, Malcolm A1 - McInnes, Colin R. A1 - Mengali, Giovanni A1 - Quatra, Alessandro A. A1 - Rios-Reyes, Leonel A1 - Scheeres, Daniel J. A1 - Seboldt, Wolfgang A1 - Wie, Bong T1 - Potential Effects of Optical Solar Sail Degradation on Interplanetary Trajectory Design JF - Astrodynamics 2005 : proceedings of the AAS/AIAA astrodynamics conference held August 7 - 11, 2005, South Lake Tahoe, California / ed. by Bobby G. Williams. - Pt. 3. - (Advances in the astronautical sciences ; 123,3) Y1 - 2006 UR - http://www.spacesailing.net/paper/200508_LakeTahoe_Dachwald+.pdf SN - 0-87703-527-X N1 - Astrodynamics Conference <2005, South Lake Tahoe, Calif.> ; American Astronautical Society ; Number: AAS-05-413 SP - 2569 EP - 2592 PB - Univelt CY - San Diego, Calif. ER - TY - JOUR A1 - Leipold, M. A1 - Fichtner, H. A1 - Heber, B. A1 - Groepper, P. A1 - Lascar, S. A1 - Burger, F. A1 - Eiden, M. A1 - Niederstadt, T. A1 - Sickinger, C. A1 - Herbeck, L. A1 - Dachwald, Bernd A1 - Seboldt, W. T1 - Heliopause Explorer - A Sailcraft Mission to the Outer Boundaries of the Solar System JF - Acta Astronautica. 59 (2006), H. 8-11 Y1 - 2006 SN - 0094-5765 N1 - International Conference on Low Cost Planetary Missions <5, 2003, Noordwijk> ; Selected Proceedings SP - 786 EP - 796 ER - TY - JOUR A1 - Dachwald, Bernd A1 - Carnelli, I. A1 - Vasile, M. T1 - Evolutionary Neurocontrol as a Novel Method for Low-Thrust Gravity Assist Trajectory Optimization / I. Carnelli ; B. Dachwald ; M. Vasile JF - Proceedings of the Twenty-Fifth International Symposium on Space Technology and Science (Selected papers) : Kanazawa, [June 4 through June 11, 2006, at Kanazawa-shi Kanko Kaikan in Kanazawa city] / [Japan Society for Aeronautical and Space Sciences. Kohtaro Matsumoto [ed.-in-chief] Y1 - 2006 SN - 4-99005-002-9 N1 - International Symposium on Space Technology and Science <25, 2006, Kanazawa> ; ISTS 2006-d-46 SP - 569 EP - 574 PB - JSASS CY - Tokyo ER - TY - PAT A1 - Mertens, Josef A1 - Velden, Alexander van der A1 - Kelm, Roland T1 - Flugzeug mit Flügeln, deren maximaler Auftrieb durch steuerbare Flügelkomponenten veränderbar ist : Offenlegungsschrift DE102004045732 ; Offenlegungstag: 30.03.2006 = Aircraft with wings whose maximum lift can be altered by controllable wing components Y1 - 2006 N1 - Zugleich EP1791755A1. - Volltext über Datenbank: http://publikationen.dpma.de/ PB - Deutsches Patent- und Markenamt CY - München ER - TY - JOUR A1 - Mertens, Josef T1 - Luft hat keine Balken, aber enorme Kräfte : Aerodynamik - die unsichtbare Kraft JF - HEmagazin : das Hocheffizienz-Magazin von Wilo. 2006 (2006), H. 1 Y1 - 2006 SP - 4 EP - 9 PB - - ER - TY - JOUR A1 - Gerhardt, Hans Joachim T1 - Wind- und Temperatureinflüsse bei der Planung von Entrauchungseinrichtungen JF - VFDB-Zeitschrift : Forschung, Technik und Management im Brandschutz. 55 (2006), H. 3 Y1 - 2006 SN - 0042-1804 SP - 115 EP - 121 ER -