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  - 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  - 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  - 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  - 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  - Havermann, Marc
T1  - Systematic Shock Tube Experiments on Vortex Ring Generation and Propagation / Havermann, M. ; Kainuma, M. ; Takayama, K.
JF  - Shock waves : proceedings of the 25th International Symposium on Shock Waves-ISSW25, July 17 - 22, 2005, Bangalore, India / ed.: G. Jagadeesh
Y1  - 2006
SN  - 978-81-7371571-6
N1  - International Symposium on Shock Waves ; 25 (Bangalore) : 2005.07.17-22
ISSW ; 25 (Bangalore) : 2005.07.17-22
PB  - Universities Pr.
CY  - Hyderabad
ER  - 
TY  - BOOK
A1  - Havermann, Marc
T1  - PIV measurements in shock tunnels : PivNet 2, Final Workshop, Göttingen, 07. - 08.09.2006
Y1  - 2006
N1  - Publication / Institut Franco-Allemand de Recherches de Saint Louis ; 644
PB  - ISL
CY  - Saint-Louis
ER  - 
TY  - BOOK
A1  - Havermann, Marc
T1  - PIV measurements of compressible vortex rings generated by a shock tube : 13th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisbon, PT, 26-29.06.2006; axe de recherches 2.14 / Haertig, J.; Rey, C.; Havermann, M. Institut Franco-Allemand de Recherches de Saint-Louis
Y1  - 2006
N1  - Publication / Institut Franco-Allemand de Recherches de Saint Louis ; 645
PB  - ISL
CY  - Saint-Louis
ER  - 
TY  - JOUR
A1  - Havermann, Marc
A1  - Seiler, F.
T1  - Boundary Layer Influence on Supersonic Jet/Cross-Flow Interaction in Hypersonic Flow / Havermann, M. ; Seiler, F.
JF  - Notes on Numerical Fluid Mechanics and Multidisciplinary Design. 92 (2006)
Y1  - 2006
SN  - 1612-2909
N1  - New results in numerical and experimental fluid mechanics ; V ;
ISBN 978-3-540-33287-9
SP  - 281
EP  - 288
PB  - -
ER  - 
TY  - BOOK
A1  - Havermann, Marc
A1  - Seiler, F.
A1  - George, A.
A1  - Srulijes, J.
T1  - Progress in doppler picture velocimetry (DPV) technique : 12th International Symposium on Flow Visualization, DLR, Göttingen, September 10 - 14, 2006 / Institut Franco-Allemand de Recherches de Saint-Louis. Seiler, F. ...
Y1  - 2006
N1  - Publication / Institut Franco-Allemand de Recherches de Saint Louis ; 624
PB  - ISL
CY  - Saint-Louis
ER  - 
TY  - CHAP
A1  - Kowalski, Julia
T1  - Numerical Debris Flow Simulation
T2  - Schweizer Numerik Kolloquium : Book of Abstracts 12. April 2006
Y1  - 2006
ER  - 
TY  - CHAP
A1  - Kowalski, Julia
A1  - McArdell, B. W.
A1  - Bartelt, Perry
T1  - A comparison of two approaches to modeling multiphase gravity currents
T2  - Geophysical Research Abstracts
Y1  - 2006
N1  - A-08738
VL  - 8
ER  - 
TY  - CHAP
A1  - Reimer, Lars
A1  - Braun, Carsten
A1  - Ballmann, Josef
T1  - Analysis of the static and dynamic aero-structural response of an elastic swept wing model by direct aeroelastic simulation
T2  - ICAS 2006 proceedings : 25th Congress of the International Council of the Aeronautical Sciences ; Hamburg, Germany, 3 - 8 September, 2006 : 25th International Congress of Aeronautical Sciences
Y1  - 2006
SN  - 0-9533991-7-6
SP  - Paper No. 2006-10.3.3
PB  - Optimage
CY  - Edinburgh
ER  - 
TY  - CHAP
A1  - Ballmann, Josef
A1  - Dafnis, Athanasios
A1  - Braun, Carsten
A1  - Korsch, Helge
A1  - Reimerdes, Hans-Günther
A1  - Braun, Carsten
A1  - Ballmann, Josef
T1  - The HIRENASD project: High Reynolds number aerostructural dynamics experiments in the European Transonic Wind Tunnel (ETW)
T2  - ICAS 2006 proceedings : 25th Congress of the International Council of the Aeronautical Sciences ; Hamburg, Germany, 3 - 8 September, 2006 : 25th International Congress of Aeronautical Sciences
Y1  - 2006
SN  - 0-9533991-7-6
SP  - Paper No. 2006-5.11.2
PB  - Optimage
CY  - Edinburgh
ER  - 
TY  - CHAP
A1  - Korsch, Helge
A1  - Dafnis, Athanasios
A1  - Reimerdes, Hans-Günther
A1  - Braun, Carsten
A1  - Ballmann, Josef
T1  - Dynamic qualification of the HIRENASD elastic wing model
T2  - Motto: Luft- und Raumfahrt: Lehre, Forschung, Industrie - gemeinsam innovativ. Deutscher Luft- und Raumfahrtkongress 2006 : Braunschweig, 06. bis 09. November 2006. Jahrbuch / Deutsche Gesellschaft für Luft- und Raumfahrt. 2006
Y1  - 2006
SP  - 1441
EP  - 1450
PB  - Dt. Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth (DGLR)
CY  - Bonn
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 <Reston, Va.> ; 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 <Reston, Va.> ; 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  - 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  - 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  -