TY  - CHAP
A1  - Grundmann, Jan Thimo
A1  - Lange, Caroline
A1  - Dachwald, Bernd
A1  - Grimm, Christian
A1  - Koch, Aaron
A1  - Ulamec, Stephan
T1  - Small Spacecraft in Planetary Defence Related Applications–Capabilities, Constraints, Challenges
T2  - IEEE Aerospace Conference
N2  - In this paper we present an overview of the characteristics and peculiarities of small spacecraft missions related to planetary defence applications. We provide a brief overview of small spacecraft missions to small solar system bodies. On this background we present recent missions and selected projects and related studies at the German Aerospace Center, DLR, that contribute to planetary defence related activities. These range from Earth orbit technology demonstrators to active science missions in interplanetary space. We provide a summary of experience from recently flown missions with DLR participation as well as a number of studies. These include PHILAE, the lander recently arrived on comet 67P/Churyumov-Gerasimenko aboard ESA’s ROSETTA comet rendezvous mission, and the Mobile Asteroid Surface Scout, MASCOT, now underway to near-Earth asteroid (162173) 1999 JU3 aboard the Japanese sample-return probe HAYABUSA-2. We introduce the differences between the conventional methods employed in the design, integration and testing of large spacecraft and the new approaches developed by small spacecraft projects. We expect that the practical experience that can be gained from projects on extremely
compressed timelines or with high-intensity operation phases on a newly explored small solar system body can contribute significantly to the study, preparation and realization of future planetary defence related missions. One is AIDA (Asteroid Impact & Deflection Assessment), a joint effort of ESA,JHU/APL, NASA, OCA and DLR, combining JHU/APL’s DART (Double Asteroid Redirection Test) and ESA’s AIM (Asteroid Impact Monitor) spacecraft in a mission towards
near-Eath binary asteroid (65803) Didymos.
KW  - small spacecraft
KW  - planetary defence
KW  - asteroid lander
KW  - solar sail
KW  - flotilla missions
Y1  - 2015
N1  - 2015 IEEE Aerospace Conference, 7.-13. Mar. 2015, Big Sky, Montana, USA.
SP  - 1
EP  - 18
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
A1  - Mengali, Giovanni
A1  - Quarta, Alessandro A.
A1  - Circi, Christian
T1  - Refined Solar Sail Force Model with Mission Application / Giovanni Mengali ; Alessandro A. Quarta , Christian Circi ;  Bernd Dachwald
JF  - Journal of Guidance, Control, and Dynamics. 30 (2007), H. 2
Y1  - 2007
SN  - 0162-3192
N1  - 2. ISBN: 0731-5090
SP  - 512
EP  - 520
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  - CHAP
A1  - Dachwald, Bernd
A1  - Mengali, Giovanni
A1  - Quarta, Alessandro A
A1  - Macdonald, Malcolm
A1  - McInnes, Colin R
T1  - Optical solar sail degradation modelling
T2  - 1st International Symposium on Solar Sailing
N2  - We propose a simple parametric OSSD 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.
Y1  - 2007
N1  - 1st International Symposium on Solar Sailing 27–29 June 2007, Herrsching, Germany
SP  - 1
EP  - 27
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
A1  - Schmidt, Tanja D.
A1  - Seboldt, Wolfgang
A1  - Auweter-Kurtz, 
T1  - Flight Opportunities from Mars to Earth for Piloted Missions Using Continuous Thrust Propulsion / Schmidt, Tanja D. ; Dachwald, Bernd ; Seboldt, Wolfgang ; Auweter-Kurtz, Monika
Y1  - 2003
N1  - 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit
20-23 July 2003, Huntsville, Alabama ; AIAA 2003-4573
SP  - 1
EP  - 9
PB  - -
ER  - 
TY  - JOUR
A1  - Hein, Andreas M.
A1  - Eubanks, T. Marshall
A1  - Hibberd, Adam
A1  - Fries, Dan
A1  - Schneider, Jean
A1  - Lingam, Manasvi
A1  - Kennedy, Robert
A1  - Perakis, Nikolaos
A1  - Dachwald, Bernd
A1  - Kervella, Pierre
T1  - Interstellar Now! Missions to and sample returns from nearby interstellar objects
N2  - The recently discovered first high velocity hyperbolic objects passing through the Solar System, 1I/'Oumuamua and 2I/Borisov, have raised the question about near term missions to Interstellar Objects. In situ spacecraft exploration of these objects will allow the direct determination of both their structure and their chemical and isotopic composition, enabling an entirely new way of studying small bodies from outside our solar system. In this paper, we map various Interstellar Object classes to mission types, demonstrating that missions to a range of Interstellar Object classes are feasible, using existing or near-term technology. We describe flyby, rendezvous and sample return missions to interstellar objects, showing various ways to explore these bodies characterizing their surface, dynamics, structure and composition. Interstellar objects likely formed very far from the solar system in both time and space; their direct exploration will constrain their formation and history, situating them within the dynamical and chemical evolution of the Galaxy. These mission types also provide the opportunity to explore solar system bodies and perform measurements in the far outer solar system.
Y1  - 2020
SP  - 1
EP  - 8
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Campen, R.
A1  - Kowalski, Julia
A1  - Lyons, W.B.
A1  - Tulaczyk, S.
A1  - Dachwald, Bernd
A1  - Pettit, E.
A1  - Welch, K. A.
A1  - Mikucki, J.A.
T1  - Microbial diversity of an Antarctic subglacial community and high‐resolution replicate sampling inform hydrological connectivity in a polar desert
JF  - Environmental Microbiology
Y1  - 2019
U6  - https://doi.org/10.1111/1462-2920.14607
SN  - 1462-2920
IS  - accepted article
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
A1  - Seboldt, Wolfgang
T1  - Multiple Near-Earth Asteroid Rendezvous and Sample Return Using First Generation Solar Sailcraft
JF  - Acta Astronautica. 57 (2005), H. 11
Y1  - 2005
SN  - 0094-5765
SP  - 864
EP  - 875
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
A1  - Boehnhardt, Herrmann
A1  - Broj, Ulrich
A1  - Geppert, Ulrich R. M. E.
A1  - Grundmann, Jan-Thimo
A1  - Seboldt, Wolfgang
A1  - Seefeldt, Patric
A1  - Spietz, Peter
A1  - Johnson, Les
A1  - Kührt, Ekkehard
A1  - Mottola, Stefano
A1  - Macdonald, Malcolm
A1  - McInnes, Colin R.
A1  - Vasile, Massimiliano
A1  - Reinhard, Ruedeger
T1  - Gossamer roadmap technology reference study for a multiple NEO Rendezvous Mission
T2  - Advances in solar sailing
N2  - A technology reference study for a multiple near-Earth object (NEO) rendezvous mission with solar sailcraft is currently carried out by the authors of this paper. The investigated mission builds on previous concepts, but adopts a strong micro-spacecraft philosophy based on the DLR/ESA Gossamer technology. The main scientific objective of the mission is to explore the diversity of NEOs. After direct interplanetary insertion, the solar sailcraft should—within less than 10 years—rendezvous three NEOs that are not only scientifically interesting, but also from the point of human spaceight and planetary defense. In this paper, the objectives of the study are outlined and a preliminary potential mission profile is presented.
Y1  - 2014
SN  - 978-3-642-34906-5 (Print) ; 978-3-642-34907-2 (E-Book)
SP  - 211
EP  - 226
PB  - Springer
CY  - Berlin [u.a.]
ER  - 
TY  - CHAP
A1  - Peloni, Alessandro
A1  - Dachwald, Bernd
A1  - Ceriotti, Matteo
T1  - Multiple NEA rendezvous mission: Solar sailing options
T2  - Fourth International Symposium on Solar Sailing
N2  - The scientific interest in near-Earth asteroids (NEAs) and the classification of some of those as potentially hazardous asteroid for the Earth stipulated the interest in NEA exploration. Close-up observations of these objects will increase drastically our knowledge about the overall NEA population. For this reason, a multiple NEA rendezvous mission through solar sailing is investigated, taking advantage of the propellantless nature of this groundbreaking propulsion technology. Considering a spacecraft based on the DLR/ESA Gossamer technology, this work focuses on the search of possible sequences of NEA encounters. The effectiveness of this approach is demonstrated through a number of fully-optimized trajectories. The results show that it is possible to visit five NEAs within 10 years with near-term solar-sail technology. Moreover, a study on a reduced NEA database demonstrates the reliability of the approach used, showing that 58% of the sequences found with an approximated trajectory model can be converted into real solar-sail trajectories. Lastly, this second study shows the effectiveness of the proposed automatic optimization algorithm, which is able to find solutions for a large number of mission scenarios without any input required from the user.
KW  - Multiphase
KW  - Trajectory Optimization
KW  - Automated Optimization
KW  - Gossamer
KW  - Sequence-Search
Y1  - 2017
N1  - Fourth International Symposium on Solar Sailing (ISSS 2017), Kyoto, Japan, 17-20 Jan 2017.
http://www.jsforum.or.jp/ISSS2017/
SP  - 1
EP  - 11
ER  - 
TY  - JOUR
A1  - Schael, S.
A1  - Atanasyan, A.
A1  - Berdugo, J.
A1  - Bretz, T.
A1  - Czupalla, Markus
A1  - Dachwald, Bernd
A1  - Doetinchem, P. von
A1  - Duranti, M.
A1  - Gast, H.
A1  - Karpinski, W.
A1  - Kirn, T.
A1  - Lübelsmeyer, K.
A1  - Maña, C.
A1  - Marrocchesi, P.S.
A1  - Mertsch, P.
A1  - Moskalenko, I.V.
A1  - Schervan, T.
A1  - Schluse, M.
A1  - Schröder, K.-U.
A1  - Schultz von Dratzig, A.
A1  - Senatore, C.
A1  - Spies, L.
A1  - Wakely, S.P.
A1  - Wlochal, M.
A1  - Uglietti, D.
A1  - Zimmermann, J.
T1  - AMS-100: The next generation magnetic spectrometer in space – An international science platform for physics and astrophysics at Lagrange point 2
JF  - Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Y1  - 2019
U6  - https://doi.org/10.1016/j.nima.2019.162561
SN  - 0168-9002
VL  - 944
IS  - 162561
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
A1  - Seboldt, Wolfgang
T1  - Solar sailcraft of the first generation mission applications to near-earth asteroids
Y1  - 2003
N1  - 54th International Astronautical Congress of the International Astronautical Federation, the International Academy of Astronautics, and the International Institute of Space Law 29 September - 3 October 2003, Bremen, Germany IAC-03-Q.5.06
ER  - 
TY  - CHAP
A1  - Konstantinidis, K.
A1  - Dachwald, Bernd
A1  - Ohndorf, A.
A1  - Dykta, P.
A1  - Voigt, K.
A1  - Förstner, R.
T1  - Enceladus explorer (ENEX): A lander mission to probe subglacial water pockets on Saturn's moon enceladus for life
T2  - 64th International Astronautical Congress 2013 (IAC 2013) : Beijing, China, 23 - 27 September 2013. (Proceedings of the International Astronautical Congress, IAC ; 2)
Y1  - 2013
SN  - 978-1-62993-909-4
SP  - 1340
EP  - 1350
PB  - Curran
CY  - Red Hook, NY
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
A1  - Feldmann, Marco
A1  - Espe, Clemens
A1  - Plescher, Engelbert
A1  - Konstantinidis, K.
A1  - Forstner, R.
T1  - Enceladus explorer - A maneuverable subsurface probe for autonomous navigation through deep ice
T2  - 63rd International Astronautical Congress 2012, IAC 2012; Naples; Italy; 1 October 2012 through 5 October 2012. (Proceedings of the International Astronautical Congress, IAC ; 3)
Y1  - 2012
SN  - 978-1-62276-979-7
SP  - 1756
EP  - 1766
PB  - Curran
CY  - Red Hook, NY
ER  - 
TY  - CHAP
A1  - Hallmann, Marcus
A1  - Heidecker, Ansgar
A1  - Schlotterer, Markus
A1  - Dachwald, Bernd
T1  - GTOC8: results and methods of team 15 DLR
T2  - 26th AAS/AIAA Space Flight Mechanics Meeting, Napa, CA
N2  - This paper describes the results and methods used during the 8th Global Trajectory Optimization Competition (GTOC) of the DLR team. Trajectory optimization is crucial for most of the space missions and usually can be formulated as a global optimization problem. A lot of research has been done to different type of mission problems. The most demanding ones are low thrust transfers with e.g. gravity assist sequences. In that case the optimal control problem is combined with an integer problem. In most of the GTOCs we apply a filtering of the problem based on domain knowledge.
Y1  - 2016
N1  - 26th AAS/AIAA Space Flight Mechanics Meeting, February 14-18, 2016, Napa, California, U.S.A. Napa, CA
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  - Spurmann, Jörn
A1  - Ohndorf, Andreas
A1  - Dachwald, Bernd
A1  - Seboldt, Wolfgang
A1  - Löb, Horst
A1  - Schartner, Karl-Heinz
T1  - Interplanetary trajectory optimization for a sep mission to Saturn
T2  - 60th International Astronautical Congress 2009
N2  - The recently proposed NASA and ESA missions to Saturn and Jupiter pose difficult tasks to mission designers because chemical propulsion scenarios are not capable of transferring heavy spacecraft into the outer solar system without the use of gravity assists. Thus our developed mission scenario based on the joint NASA/ESA Titan Saturn System Mission baselines solar electric propulsion to improve mission flexibility and transfer time. For the calculation of near-globally optimal low-thrust trajectories, we have used a method called Evolutionary Neurocontrol, which is implemented in the low-thrust trajectory optimization software InTrance. The studied solar electric propulsion scenario covers trajectory optimization of the interplanetary transfer including variations of the spacecraft's thrust level, the thrust unit's specific impulse and the solar power generator power level. Additionally developed software extensions enabled trajectory optimization with launcher-provided hyperbolic excess energy, a complex solar power generator model and a variable specific impulse ion engine model. For the investigated mission scenario, Evolutionary Neurocontrol yields good optimization results, which also hold valid for the more elaborate spacecraft models. Compared to Cassini/Huygens, the best found solutions have faster transfer times and a higher mission flexibility in general.
KW  - Spacecraft
KW  - Reusable Rocket Engines
KW  - Hybrid Propellants
Y1  - 2009
SN  - 9781615679089
N1  - 60th International Astronautical Congress 2009 (IAC 2009)
Held 12-16 October 2009, Daejeon, Republic of Korea.
SP  - 5234
EP  - 5248
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
A1  - Carnelli, I.
A1  - Vasile, M.
T1  - Optimizing low-thrust gravity assist interplanetary trajectories using evolutionary neurocontrollers / I. Carnelli ; B. Dachwald ; M. Vasile
JF  - IEEE Congress on Evolutionary Computation, 2007 : CEC 2007 ; 25 - 28 September 2007, Singapore
Y1  - 2007
SN  - 978-1-424-41339-3
N1  - ISBN 10: 1-424-41339-7 ; IEEE Congress on Evolutionary Computation <2007, Singapore> ; 	Institute of Electrical and Electronics Engineers ; Nebent: CEC 2007 ; Parallel als Online-Ausg. erschienen
SP  - 965
EP  - 972
PB  - IEEE Service Center
CY  - Piscataway, NJ
ER  - 
TY  - CHAP
A1  - Macdonald, Malcolm
A1  - McGrath, C.
A1  - Appourchaux, T.
A1  - Dachwald, Bernd
A1  - Finsterle, W.
A1  - Gizon, L.
A1  - Liewer, P. C.
A1  - McInnes, Colin R.
A1  - Mengali, G.
A1  - Seboldt, Wolfgang
A1  - Sekii, T.
A1  - Solanki, S. K.
A1  - Velli, M.
A1  - Wimmer-Schweingruber, R. F.
A1  - Spietz, Peter
A1  - Reinhard, Ruedeger
ED  - Macdonald, Malcolm
T1  - Gossamer roadmap technology reference study for a solar polar mission
T2  - Advances in solar sailing
N2  - A technology reference study for a solar polar mission is presented. The study uses novel analytical methods to quantify the mission design space including the required sail performance to achieve a given solar polar observation angle within a given timeframe and thus to derive mass allocations for the remaining spacecraft sub-systems, that is excluding the solar sail sub-system. A parametric, bottom-up, system mass budget analysis is then used to establish the required sail technology to deliver a range of science payloads, and to establish where such payloads can be delivered to within a given timeframe. It is found that a solar polar mission requires a solar sail of side-length 100–125 m to deliver a ‘sufficient value’ minimum science payload, and that a 2.5 μm sail film substrate is typically required, however the design is much less sensitive to the boom specific mass.
Y1  - 2014
SN  - 978-3-642-34906-5
U6  - https://doi.org/10.1007/978-3-642-34907-2_17
SP  - 243
EP  - 257
PB  - Springer
CY  - Berlin, Heidelberg
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
A1  - McDonald, Malcolm
A1  - McInnes, Colin R.
A1  - Mengali, Giovanni
T1  - Impact of Optical Degradation on Solar Sail Mission Performance
JF  - Journal of Spacecraft and Rockets. 44 (2007), H. 4
Y1  - 2007
SN  - 0022-4650
N1  - 2. ISSN: 1533-6794
SP  - 740
EP  - 749
ER  -