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  - CHAP
A1  - Grundmann, Jan Thimo
A1  - Borella, Laura
A1  - Ceriotti, Matteo
A1  - Chand, Suditi
A1  - Cordero, Federico
A1  - Dachwald, Bernd
A1  - Fexer, Sebastian
A1  - Grimm, Christian D.
A1  - Hendrikse, Jeffrey
A1  - Herčík, David
A1  - Herique, Alain
A1  - Hillebrandt, Martin
A1  - Ho, Tra-Mi
A1  - Kesseler, Lars
A1  - Laabs, Martin
A1  - Lange, Caroline
A1  - Lange, Michael
A1  - Lichtenheldt, Roy
A1  - McInnes, Colin R.
A1  - Moore, Iain
A1  - Peloni, Alessandro
A1  - Plettenmeier, Dirk
A1  - Quantius, Dominik
A1  - Seefeldt, Patric
A1  - Venditti, Flaviane c. F.
A1  - Vergaaij, Merel
A1  - Viavattene, Giulia
A1  - Virkki, Anne K.
A1  - Zander, Martin
T1  - More bucks for the bang: new space solutions, impact tourism and one unique science & engineering opportunity at T-6 months and counting
T2  - 7th IAA Planetary Defense Conference
N2  - For now, the Planetary Defense Conference Exercise 2021's incoming fictitious(!), asteroid, 2021 PDC, seems headed for impact on October 20th, 2021, exactly 6 months after its discovery. Today (April 26th, 2021), the impact probability is 5%, in a steep rise from 1 in 2500 upon discovery six days ago. We all know how these things end. Or do we? Unless somebody kicked off another headline-grabbing media scare or wants to keep civil defense very idle very soon, chances are that it will hit (note: this is an exercise!). Taking stock, it is barely 6 months to impact, a steadily rising likelihood that it will actually happen, and a huge uncertainty of possible impact energies: First estimates range from 1.2 MtTNT to 13 GtTNT, and this is not even the worst-worst case: a 700 m diameter massive NiFe asteroid (covered by a thin veneer of Ryugu-black rubble to match size and brightness), would come in at 70 GtTNT. In down to Earth terms, this could be all between smashing fireworks over some remote area of the globe and a 7.5 km crater downtown somewhere. Considering the deliberate and sedate ways of development of interplanetary missions it seems we can only stand and stare until we know well enough where to tell people to pack up all that can be moved at all and save themselves. But then, it could just as well be a smaller bright rock. The best estimate is 120 m diameter from optical observation alone, by 13% standard albedo. NASA's upcoming DART mission to binary asteroid (65803) Didymos is designed to hit such a small target, its moonlet Dimorphos. The Deep Impact mission's impactor in 2005 successfully guided itself to the brightest spot on comet 9P/Tempel 1, a relatively small feature on the 6 km nucleus. And 'space' has changed: By the end of this decade, one satellite communication network plans to have launched over 11000 satellites at a pace of 60 per launch every other week. This level of series production is comparable in numbers to the most prolific commercial airliners. Launch vehicle production has not simply increased correspondingly – they can be reused, although in a trade for performance. Optical and radio astronomy as well as planetary radar have made great strides in the past decade, and so has the design and production capability for everyday 'high-tech' products. 60 years ago, spaceflight was invented from scratch within two years, and there are recent examples of fast-paced space projects as well as a drive towards 'responsive space'. It seems it is not quite yet time to abandon all hope. We present what could be done and what is too close to call once thinking is shoved out of the box by a clear and present danger, to show where a little more preparedness or routine would come in handy – or become decisive. And if we fail, let's stand and stare safely and well instrumented anywhere on Earth together in the greatest adventure of science.
Y1  - 2021
N1  - 7th IAA Planetary Defense Conference, Vienna, Austria, 26-30 April 2021
ER  - 
TY  - CHAP
A1  - Röth, Thilo
T1  - Modularisierung in der Karosserie von morgen
N2  - 1) Module werden die Fahrzeugplattform und den –aufbau in Zukunft weiterhin und in zunehmendem Maße bestimmen. 2) Neue Module und Modulschnittstellen am Fahrzeug werden überdacht und können in der Zukunft erwartet werden. 3) Die Wertschöpfung und der Entwicklungsumfang wird sich vom OEM zum Modullieferanten verlagern. 4) Modulvergaben werden in der Zukunft noch stärker auf Innovation und Kostenreduktion beruhen. 5) Modularisierung des Fahrzeuges heißt ein Aufbrechen der Fahrzeugkarosserie und wird daher von der Beherrschung struktureller Aufgaben sowie der Lösung der (sichtbaren) Modulübergänge bestimmt sein. 6) Neben den Systemintegratoren und den Komponentenspezialisten besetzen die Modullieferanten die erste Lieferantenriege. 7) Der Modullieferant wird neben höchster Fertigungsexpertise ein hohes Maß an (Teil-)fahrzeug-Know-How und Produktentwickler-mentalität bereitstellen.
KW  - Karosseriebau
KW  - Karosseriebau
KW  - car body construction
Y1  - 2002
ER  - 
TY  - CHAP
A1  - Kapoor, Hrshi
A1  - Braun, Carsten
A1  - Boller, Christian
ED  - Casciati, Fabio
T1  - Modelling and optimisation of maintenance intervals to realize structural health monitoring applications on aircraft
T2  - Structural health monitoring 2010 : proceedings of the Fifth European Workshop on Structural Health Monitoring held at Sorrento, Naples, Italy, June 28 - July 4, 2010 ; [EWSHM]
Y1  - 2010
SN  - 978-1-60595-024-2
SP  - 55
EP  - 63
PB  - DEStech Publ.
CY  - Lancaster, Pa.
ER  - 
TY  - CHAP
A1  - Theis, Jochen
A1  - Krisnamurthy, Hemanth Kumar
A1  - Schmitz, Günter
ED  - Jamal, Rahman
T1  - Modellbasierte Simulation und experimentelle Anwendung von mechatronischen Systemen in der Lehre in Verbindung mit NI myRIO und dem NI LabVIEW Interface Toolkit
T2  - Virtuelle Instrumente in der Praxis 2015 : Mess-, Steuer-, Regel- und Embedded-Systeme; Begleitband zum 20. VIP-Kongress
Y1  - 2015
SN  - 978-3-8007-3669-0
SP  - 362
EP  - 365
PB  - VDE-Verl.
CY  - Berlin
ER  - 
TY  - CHAP
A1  - Carzana, Livio
A1  - Dachwald, Bernd
A1  - Noomen, Ron
T1  - Model and trajectory optimization for an ideal laser-enhanced solar sail
T2  - 68th International Astronautical Congress
N2  - A laser-enhanced solar sail is a solar sail that is not solely propelled by solar radiation but additionally by a laser beam that illuminates the sail. This way, the propulsive acceleration of the sail results from the combined action of the solar and the laser radiation pressure onto the sail. The potential source of the laser beam is a laser satellite that coverts solar power (in the inner solar system) or nuclear power (in the outer solar system) into laser power. Such a laser satellite (or many of them) can orbit anywhere in the solar system and its optimal orbit (or their optimal orbits) for a given mission is a subject for future research. This contribution provides the model for an ideal laser-enhanced solar sail and investigates how a laser can enhance the thrusting capability of such a sail. The term ”ideal” means that the solar sail is assumed to be perfectly reflecting and that the laser beam is assumed to have a constant areal power density over the whole sail area. Since a laser beam has a limited divergence, it can provide radiation pressure at much larger solar distances and increase the radiation pressure force into the desired direction. Therefore, laser-enhanced solar sails may make missions feasible, that would otherwise have prohibitively long flight times, e.g. rendezvous missions in the outer solar system. This contribution will also analyze exemplary mission scenarios and present optimial trajectories without laying too much emphasis on the design and operations of the laser satellites. If the mission studies conclude that laser-enhanced solar sails would have advantages with respect to ”traditional” solar sails, a detailed study of the laser satellites and the whole system architecture would be the second next step
Y1  - 2017
N1  - 68th International Astronautical Congress: Unlocking Imagination, Fostering Innovation and Strengthening Security, IAC 2017, 2017-09-25 → 2017-09-29, Adelaide, Australia
ER  - 
TY  - CHAP
A1  - Borggräfe, Andreas
A1  - Dachwald, Bernd
T1  - Mission performance evaluation for solar sails using a refined SRP force model with variable optical coefficients
T2  - 2nd International Symposium on Solar Sailing
N2  - Solar sails provide ignificant advantages over other low-thrust propulsion systems because they produce thrust by the momentum exchange from solar radiation pressure (SRP) and thus do not consume any propellant.The force exerted on a very thin sail foil basically depends on the light incidence angle. Several analytical SRP force models that describe the SRP force acting on the sail have been established since the 1970s. All the widely used models use constant optical force coefficients of the reflecting sail material. In 2006,MENGALI et al. proposed a refined SRP force model that takes into account the dependancy of the force coefficients on the light incident angle,the sail’s distance from the sun (and thus the sail emperature) and the surface roughness of the sail material [1]. In this paper, the refined SRP force model is compared to the previous ones in order to identify the potential impact of the new model on the predicted capabilities of solar sails in performing low-cost interplanetary space missions. All force models have been implemented within InTrance, a global low-thrust trajectory optimization software utilizing evolutionary neurocontrol [2]. Two interplanetary rendezvous missions, to Mercury and the near-Earth asteroid 1996FG3, are investigated. Two solar sail performances in terms of characteristic acceleration are examined for both scenarios, 0.2 mm/s2 and 0.5 mm/s2, termed “low” and “medium” sail performance. In case of the refined SRP model, three different values of surface roughness are chosen, h = 0 nm, 10 nm and 25 nm. The results show that the refined SRP force model yields shorter transfer times than the standard model.
Y1  - 2010
N1  - 2nd International Symposium on Solar Sailing, ISSS 2010, 2010-07-20 - 2010-07-22. New York City College of Technology of the City University of New York, USA
SP  - 1
EP  - 6
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
A1  - Wurm, P.
T1  - Mission analysis for an advanced solar photon thruster
T2  - 60th International Astronautical Congress 2009, IAC 2009
N2  - The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), is a solar sail design concept, for which the two basic functions of the solar sail, namely light collection and thrust direction, are uncoupled. In this paper, we introduce a novel SPT concept, termed the Advanced Solar Photon Thruster (ASPT). This model does not suffer from the simplified assumptions that have been made for the analysis of compound solar sails in previous studies. We present the equations that describe the force, which acts on the ASPT. After a detailed design analysis, the performance of the ASPT with respect to the conventional flat solar sail (FSS) is investigated for three interplanetary mission scenarios: An Earth-Venus rendezvous, where the solar sail has to spiral towards the Sun, an Earth-Mars rendezvous, where the solar sail has to spiral away from the Sun, and an Earth-NEA rendezvous (to near-Earth asteroid 1996FG3), where a large orbital eccentricity change is required. The investigated solar sails have realistic near-term characteristic accelerations between 0.1 and 0.2mm/s2. Our results show that a SPT is not superior to the flat solar sail unless very idealistic assumptions are made.
KW  - Interplanetary flight
Y1  - 2009
SN  - 978-161567908-9
N1  - 60th International Astronautical Congress 2009, IAC 2009; Daejeon; South Korea; 12 October 2009 through 16 October 2009
VL  - Vol. 8
SP  - 6838
EP  - 6851
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Finger, Felix
A1  - Götten, Falk
A1  - Braun, Carsten
A1  - Bil, Cees
T1  - Mass, Primary Energy, and Cost - The Impact of Optimization Objectives on the Initial Sizing of Hybrid-Electric General Aviation Aircraft
T2  - Deutscher Luft- und Raumfahrtkongress 2019, DLRK 2019. Darmstadt, Germany
Y1  - 2019
U6  - http://dx.doi.org/10.25967/490012
SP  - 1
EP  - 17
ER  - 
TY  - CHAP
A1  - Weber, Tobias
T1  - Manufacturing Process Simulation for Tooling Optimization: Reduction of Quality Issues During Autoclave Manufacturing of Composite Parts
T2  - Proceedings of SAMPE Europe Conference 2015, Amiens, France
Y1  - 2015
SP  - 1
EP  - 8
ER  - 
TY  - CHAP
A1  - Weber, Tobias
A1  - Englhard, Markus
A1  - Hailer, Benjamin
A1  - Arent, Jan-Christoph
T1  - Manufacturing Process Simulation for the Prediction of Tool-Part-Interaction and Ply Wrinkling
T2  - Proceedings of SAMPE Europe Conference 2019, Nantes, France
Y1  - 2019
SP  - 1
EP  - 10
ER  - 
TY  - CHAP
A1  - Weber, Tobias
A1  - Englhard, Markus
A1  - Hailer, Benjamin
A1  - Arent, Jan-Christoph
T1  - Manufacturing Process Simulation for the Prediction of Tool-Part-Interaction and Ply Wrinkling
T2  - Proceedings of SAMPE Europe Conference, Amiens , France
Y1  - 2015
SP  - 1
EP  - 10
ER  - 
TY  - CHAP
A1  - Hailer, Benjamin
A1  - Weber, Tobias
A1  - Arent, Jan-Christoph
T1  - Manufacturing Process Simulation for Autoclave-Produced Sandwich Structures
T2  - Proceedings of SAMPE Europe Conference 2019, Nantes, France
Y1  - 2019
SP  - 1
EP  - 8
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
T1  - Low-Thrust Mission Analysis and Global Trajectory Optimization Using Evolutionary Neurocontrol: New Results
T2  - European Workshop on Space Mission Analysis ESA/ESOC, Darmstadt, Germany 10 { 12 Dec 2007
N2  - Interplanetary trajectories for low-thrust spacecraft are often characterized by multiple revolutions around the sun. Unfortunately, the convergence of traditional trajectory optimizers that are based on numerical optimal control methods depends strongly on an adequate initial guess for the control function (if a direct method is used) or for the starting values of the adjoint vector (if an indirect method is used). Especially when many revolutions around the sun are re-
quired, trajectory optimization becomes a very difficult and time-consuming task that involves a lot of experience and expert knowledge in astrodynamics and optimal control theory, because an adequate initial guess is extremely hard to find. Evolutionary neurocontrol (ENC) was proposed as a smart method for low-thrust trajectory optimization that fuses artificial neural networks and evolutionary algorithms to so-called evolutionary neurocontrollers (ENCs) [1]. Inspired by natural archetypes, ENC attacks the trajectoryoptimization problem from the perspective of artificial intelligence and machine learning, a perspective that is quite different from that of optimal control theory. Within the context of ENC, a trajectory is regarded as the result of a spacecraft steering strategy that maps permanently the actual spacecraft state and the actual target state onto the actual spacecraft control vector. This way, the problem of searching the optimal spacecraft trajectory is equivalent to the problem of searching (or "learning") the optimal spacecraft steering strategy. An artificial neural network is used to implement such a spacecraft steering strategy. It can be regarded as a parameterized function (the network function) that is defined by the internal network parameters. Therefore, each distinct set of network parameters defines a different network function and thus a different steering strategy. The problem of searching the optimal steering strategy is now equivalent to the problem of searching the optimal set of network parameters. Evolutionary algorithms that work on a population of (artificial) chromosomes are used to find the optimal network parameters, because the parameters can be easily mapped onto a chromosome. The trajectory optimization problem is solved when the optimal chromosome is found. A comparison of solar sail trajectories that have been published by others [2, 3, 4, 5] with ENC-trajectories has shown that ENCs can be successfully applied for near-globally optimal spacecraft control [1, 6] and that they are able to find trajectories that are closer to the (unknown) global optimum, because they explore the trajectory search space more exhaustively than a human expert can do. The obtained trajectories are fairly accurate with respect to the terminal constraint. If a more accurate trajectory is required, the ENC-solution can be used as an initial guess for a local trajectory optimization method. Using ENC, low-thrust trajectories can be optimized without an initial guess and without expert attendance.
Here, new results for nuclear electric spacecraft and for solar sail spacecraft are presented and it will be shown that ENCs find very good trajectories even for very difficult problems. Trajectory optimization results are presented for 1. NASA's Solar Polar Imager Mission, a mission to attain a highly inclined close solar orbit with a solar sail [7] 2. a mission to de ect asteroid Apophis with a solar sail from a retrograde orbit with a very-high velocity impact [8, 9] 3. JPL's \2nd Global Trajectory Optimization Competition", a grand tour to visit four asteroids from different classes with a NEP spacecraft
Y1  - 2007
ER  - 
TY  - CHAP
A1  - Funke, Harald
A1  - Börner, Sebastian
A1  - Keinz, Jan
A1  - Hendrick, P.
A1  - Recker, E.
T1  - Low NOx Hydrogen combustion chamber for industrial gas turbine applications“, 14th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery
T2  - ISROMAC-14 : the Forteenth International Symposium on Transport Phenomena and Dynamics of Rotating Machinery ; Honolulu, Hawaii, February 27 - March 02nd, 2012
Y1  - 2012
N1  - International Symposium on Transport Phenomena and Dynamics of Rotating Machinery ; (14 ; 2012.02.27-03.02 ; Honolulu, Hawaii)
ER  - 
TY  - CHAP
A1  - Börner, Sebastian
A1  - Funke, Harald
A1  - Hendrick, P.
A1  - Recker, E.
T1  - LES of Jets In Cross-Flow and Application to the “Micromix” Hydrogen Combustion
T2  - XIX International Symposium on Air Breathing Engines 2009 (ISABE 2009) : Proceedings of a meeting held 7-11 September 2009, Montreal, Canada
Y1  - 2009
SN  - 9781615676064
SP  - 1555
EP  - 1561
ER  - 
TY  - CHAP
A1  - Pasligh, N.
A1  - Funke, D.
A1  - Röth, Thilo
A1  - Krack, R.
T1  - Leichtbau Quertrager als Stahlblech-Aluminiumdruckguss-Hybrid - Von der numerischen Berechnung bis zum realen Prototypen
T2  - VDI BERICHTE
Y1  - 2010
SN  - 978-3-18-092107-5
N1  - 15. Kongress SIMVEC Berechnung und Simulation im Fahrzeugbau, 
Baden-Baden, 16. und 17. November 2010
PB  - VDI Verlag
CY  - Düsseldorf
ER  - 
TY  - CHAP
A1  - Seefeldt, Patric
A1  - Bauer, Waldemar
A1  - Dachwald, Bernd
A1  - Grundmann, Jan Thimo
A1  - Straubel, Marco
A1  - Sznajder, Maciej
A1  - Tóth, Norbert
A1  - Zander, Martin E.
T1  - Large lightweight deployable structures for planetary defence: solar sail propulsion, solar concentrator payloads, large-scale photovoltaic power
T2  - 4th IAA Planetary Defense Conference - PDC 2015, 13-17 April 2015, Frascati, Roma, Italy
Y1  - 2015
N1  - IAA-PDC-15-P-20
ER  - 
TY  - CHAP
A1  - Mertens, Josef
T1  - Laminar leading edges: manufacturing, contamination, and operational aspects - results from the German RaWid programme
N2  - RaWid was the German national technology programme on transonic aerodynamics and supporting technologies, lasting from 1995 to 1998. One of the main topics was laminar wing development. Besides aerodynamic design work, many operational aspects were investigated. A manufacturing concept was developed to be applied to operational laminar wings and empennages. It was built in a large scale manufacturing demonstrator with the aerodynamic shape of a 1,5 m section of the A320 fin nose. Tolerances in shape and roughness fulfilled all requirements. The construction can easily be adapted to varying stiffness and strength requirements. Weight and manufacturing costs are comparable to common nose designs. The mock-up to be designed in ALTTA is based on this manufacturing principle. Another critical point is contamination of suction surfaces. Several tests were performed to investigate perforated titanium suction surfaces at realistic operational conditions: - a one year flight test with a suction plate in the stagnation area of the Airbus "Beluga" - a one year test of several suction plates in a ground test near the airport - a one year test of a working suction ground test installation at all weather conditions. No critical results were found. There is no long term suction degradation visible. Icing conditions and ground de-icing fluids used on airports did not pose severe problems. Some problems detected require only respection of weak design constraints.
KW  - Laminare Strömung
KW  - Ansaugsystem
KW  - Profilumströmung
KW  - Laminarprofil
KW  - RaWid
KW  - hybrid laminar flow
KW  - suction systems
KW  - suction structure
KW  - contamination
KW  - operational aspects
Y1  - 2000
ER  - 
TY  - CHAP
A1  - Weiss, Alexander
A1  - Abanteriba, Sylvester
A1  - Esch, Thomas
T1  - Investigation of Flow Separation Inside a Conical Rocket Nozzle With the Aid of an Annular Cross Flow
T2  - Proceedings of the ASME/JSME 2007 5th Joint Fluids Engineering Conference. Volume 1: Symposia, Parts A and B
N2  - Flow separation is a phenomenon that occurs in all kinds of supersonic nozzles sometimes during run-up and shut-down operations. Especially in expansion nozzles of rocket engines with large area ratio, flow separation can trigger strong side loads that can damage the structure of the nozzle. The investigation presented in this paper seeks to establish measures that may be applied to alter the point of flow separation. In order to achieve this, a supersonic nozzle was placed at the exit plane of the conical nozzle. This resulted in the generation of cross flow surrounding the core jet flow from the conical nozzle. Due to the entrainment of the gas stream from the conical nozzle the pressure in its exit plane was found to be lower than that of the ambient. A Cold gas instead of hot combustion gases was used as the working fluid. A mathematical simulation of the concept was validated by experiment. Measurements confirmed the simulation results that due to the introduction of a second nozzle the pressure in the separated region of the conical nozzle was significantly reduced. It was also established that the boundary layer separation inside the conical nozzle was delayed thus allowing an increased degree of overexpansion. The condition established by the pressure measurements was also demonstrated qualitatively using transparent nozzle configurations.
Y1  - 2007
SN  - 0-7918-4288-6
U6  - http://dx.doi.org/10.1115/FEDSM2007-37387
N1  - Proceedings of the ASME/JSME 2007 5th Joint Fluids Engineering Conference. Volume 1: Symposia, Parts A and B. San Diego, California, USA. July 30–August 2, 2007
SP  - 1861
EP  - 1871
PB  - American Society of Mechanical Engineers (ASME)
CY  - New York
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  - CHAP
A1  - Röth, Thilo
A1  - Tragsdorf, Carsten
T1  - Innovativer Einsatz von Werkstoffen - Trends und Entwicklungen im Karosserieleichtbau
N2  - 1) In Karosseriestrukturen steht der richtige Werkstoffeinsatz stärker den je im Spannungsfeld von Leichtbau, Kosten (Stückzahlen) und Leistungsanforderung 2) In „klassischen“ Strukturen von Modulträgern und Klappen hat sich die Materialmischbauweise verstärkt in den letzten Jahren durchgesetzt 3) Unter Aspekten des konzeptionellen Leichtbaus erscheint der verstärkte Einsatz von Leichtbauwerkstoffen im Vorderwagen sowie in der Dachstruktur zielführend 4) Offene Strukturprofile in Materialmischbauweise liefern für eine Vielzahl von Anwendungen ein interessantes und bis dato kaum genutztes Potential 5) Neue Entwicklungen bei den Fügetechnologien (i.b. kontinuierliche Fügeverbindungen und kombinierte Verfahren) unterstützen den wirtschaftlichen Karosserieleichtbau 6) Werkstoffinnovationen sowie neuartige Fertigungsverfahren machen den Konstruktionswerkstoff „Stahl“ auch in der Zukunft im Karosseriebau weiterhin sehr attraktiv
KW  - Karosseriebau
KW  - Leichtbau
KW  - Karosserieleichtbau
KW  - Materialmischbauweise
KW  - Leichtbauwerkstoffe
Y1  - 2004
ER  - 
TY  - CHAP
A1  - Huth, Thomas
A1  - Elsen, Olaf
A1  - Hartwig, Christoph
A1  - Esch, Thomas
T1  - Innovative modular valve trains for 2015 - logistic benefits by EMVT
T2  - IFAC Proceedings Volumes, Volume 39, Issue 3
N2  - In this paper the way to a 5-day-car with respect to a modular valve train systems for spark ignited combustion engines is shown. The necessary product diversity is shift from mechanical or physical components to software components. Therefore, significant improvements of logistic indicators are expected and shown. The working principle of a camless cylinder head with respect to an electromagnetical valve train (EMVT) is explained and it is demonstrated that shifting physical diversity to software is feasible. The future design of combustion engine systems including customisation can be supported by a set of assistance tools which is shown exemplary.
Y1  - 2006
U6  - http://dx.doi.org/10.3182/20060517-3-FR-2903.00172
N1  - Part of special issue "12th IFAC Symposium on Information Control Problems in Manufacturing"
SP  - 315
EP  - 320
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Finger, Felix
A1  - Götten, Falk
A1  - Braun, Carsten
T1  - Initial Sizing for a Family of Hybrid-Electric VTOL General Aviation Aircraft
T2  - 67. Deutscher Luft- und Raumfahrtkongress 2018
Y1  - 2018
ER  - 
TY  - CHAP
A1  - Hoefling, J.
A1  - Schirra, Julian
A1  - Spohr, A.
A1  - Schäfer, D.
T1  - Induced drag computation with wake model schemes for highly non-planar wing systems
T2  - Deutscher Luft- und Raumfahrtkongress 2013 : 10.9. - 12.9.2013, Stuttgart
Y1  - 2013
SP  - 1
EP  - 10
PB  - Dt. Ges. für Luft- und Raumfahrt
CY  - Bonn
ER  - 
TY  - CHAP
A1  - Thenent, N. E.
A1  - Dahmann, Peter
T1  - Increasing aircraft design flexibility ‐ The development of a hydrostatic transmission for gliders with self‐launching capability
T2  - Deutscher Luft- und Raumfahrtkongress 2011 : Bremen, 27. bis 29. September 2011 ; Tagungsband
Y1  - 2011
SN  - 978-3-9321-8274-7
SP  - 865
EP  - 883
PB  - Dt. Gesellschaft für Luft- und Raumfahrt
CY  - Bonn
ER  - 
TY  - CHAP
A1  - Neu, Eugen
A1  - Janser, Frank
A1  - Khatibi, Akbar A.
A1  - Orifici, Adrian C.
T1  - In-flight vibration-based structural health monitoring of aircraft wings
T2  - 30th Congress of the internatonal council of the aeronautical sciences : 25.-30. September 2016, Daejeon, Korea
N2  - This work presents a methodology for automated
damage-sensitive feature extraction and anomaly
detection under multivariate operational variability
for in-flight assessment of wings. The
method uses a passive excitation approach, i. e.
without the need for artificial actuation. The
modal system properties (natural frequencies and
damping ratios) are used as damage-sensitive
features. Special emphasis is placed on the use
of Fiber Bragg Grating (FBG) sensing technology
and the consideration of Operational and
Environmental Variability (OEV). Measurements
from a wind tunnel investigation with a composite
cantilever equipped with FBG and piezoelectric
sensors are used to successfully detect an impact
damage. In addition, the feasibility of damage
localisation and severity estimation is evaluated
based on the coupling found between damageand
OEV-induced feature changes.
Y1  - 2016
ER  - 
TY  - CHAP
A1  - Thoma, Andreas
A1  - Fisher, Alex
A1  - Braun, Carsten
T1  - Improving the px4 avoid algorithm by bio-inspired flight strategies
T2  - DLRK2020 - „Luft- und Raumfahrt – Verantwortung in allen Dimensionen“
Y1  - 2020
N1  - Deutscher Luft- und Raumfahrtkongress 2020, 1. bis 3. September 2020 – Online, „Luft- und Raumfahrt – Verantwortung in allen Dimensionen“
ER  - 
TY  - CHAP
A1  - Ludowicy, Jonas
A1  - Rings, René
A1  - Finger, Felix
A1  - Braun, Carsten
A1  - Bil, Cees
T1  - Impact of Propulsion Technology Levels on the Sizing and Energy Consumption for Serial HybridElectric General Aviation Aircraft
T2  - Asia Pacific International Symposium on Aerospace Technology. APISAT 2019
Y1  - 2019
ER  - 
TY  - CHAP
A1  - Finger, Felix
A1  - Braun, Carsten
A1  - Bil, Cees
T1  - Impact of Engine Failure Constraints on the Initial Sizing of Hybrid-Electric GA Aircraft
T2  - AIAA Scitech 2019 Forum
Y1  - 2019
U6  - http://dx.doi.org/10.2514/6.2019-1812
N1  - AIAA Scitech Forum, 2019; San Diego; United States; 7 January 2019 through 11 January 2019
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
A1  - Xu, Changsheng
A1  - Feldmann, Marco
A1  - Plescher, Engelbert
T1  - IceMole : Development of a novel subsurface ice probe and testing of the first prototype on the Morteratsch Glacier
T2  - EGU General Assembly 2011 Vienna | Austria | 03 – 08 April 2011
N2  - We present the novel concept of a combined drilling and melting probe for subsurface ice research. This probe, named “IceMole”, is currently developed, built, and tested at the FH Aachen University of Applied Sciences’ Astronautical Laboratory. Here, we describe its first prototype design and report the results of its field tests on the Swiss Morteratsch glacier. Although the IceMole design is currently adapted to terrestrial glaciers and ice shields, it may later be modified for the subsurface in-situ investigation of extraterrestrial ice, e.g., on Mars, Europa, and Enceladus. If life exists on those bodies, it may be present in the ice (as life can also be found in the deep ice of Earth).
Y1  - 2011
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
A1  - Mikucki, Jill A.
A1  - Tulaczyk, Slawek
A1  - Digel, Ilya
A1  - Feldmann, Marco
A1  - Espe, Clemens
A1  - Plescher, Engelbert
A1  - Xu, Changsheng
T1  - IceMole - a maneuverable probe for clean in-situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems : extended abstract / SCAR Open Science Conference 2012, Session 29: Advancing Clean Technologies for Exploration of Glacial Aquatic Ecosystems
N2  - The ”IceMole“ is a novel maneuverable subsurface ice probe for clean in-situ analysis and sampling of subsurface ice and subglacial water/brine. It is developed and build at FH Aachen University of Applied Sciences’ Astronautical Laboratory. A first prototype was successfully tested on the Swiss Morteratsch glacier in 2010. Clean sampling is achieved with a hollow ice screw (as it is used in mountaineering) at the tip of the probe. Maneuverability is achieved with a differentially heated melting head. Funded by the German Space Agency (DLR), a consortium led by FH Aachen currently develops a much more advanced IceMole probe, which includes a sophisticated system for obstacle avoidance, target detection, and navigation in the ice. We intend to use this probe for taking clean samples of subglacial brine at the Blood Falls (McMurdo Dry Valleys, East Antarctica) for chemical and microbiological analysis. In our conference contribution, we 1) describe the IceMole design, 2) report the results of the field tests of the first prototype on the Morteratsch glacier, 3) discuss the probe’s potential for the clean in-situ analysis and sampling of subsurface ice and subglacial liquids, and 4) outline the way ahead in the development of this technology.
KW  - Eisschicht
KW  - Sonde
KW  - subsurface ice
KW  - subglacial aquatic ecosystems
Y1  - 2012
ER  - 
TY  - CHAP
A1  - Thenent, N. E.
A1  - Dahmann, Peter
T1  - Hydrostatic propeller drive
T2  - Proceedings of the conference : 18 - 20 May, 2011 Tampere, Finland / the Twelth Scandinavian International Conference on Fluid Power, SICFP'11. Ed.: Harri Sairiala ... Vol. 1
Y1  - 2011
SN  - 978-952-15-2517-9
SP  - 217
EP  - 227
CY  - Tampere
ER  - 
TY  - CHAP
A1  - Funke, Harald
A1  - Beckmann, Nils
A1  - Stefan, Lukas
A1  - Keinz, Jan
T1  - Hydrogen combustor integration study for a medium range aircraft engine using the dry-low NOx “Micromix” combustion principle
T2  - Proceedings of the ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition. Volume 1: Aircraft Engine. Boston, Massachusetts, USA. June 26–30, 2023
N2  - The feasibility study presents results of a hydrogen combustor integration for a Medium-Range aircraft engine using the Dry-Low-NOₓ Micromix combustion principle. Based on a simplified Airbus A320-type flight mission, a thermodynamic performance model of a kerosene and a hydrogen-powered V2530-A5 engine is used to derive the thermodynamic combustor boundary conditions. A new combustor design using the Dry-Low NOx Micromix principle is investigated by slice model CFD simulations of a single Micromix injector for design and off-design operation of the engine. Combustion characteristics show typical Micromix flame shapes and good combustion efficiencies for all flight mission operating points. Nitric oxide emissions are significant below ICAO CAEP/8 limits. For comparison of the Emission Index (EI) for NOₓ emissions between kerosene and hydrogen operation, an energy (kerosene) equivalent Emission Index is used.

A full 15° sector model CFD simulation of the combustion chamber with multiple Micromix injectors including inflow homogenization and dilution and cooling air flows investigates the combustor integration effects, resulting NOₓ emission and radial temperature distributions at the combustor outlet. The results show that the integration of a Micromix hydrogen combustor in actual aircraft engines is feasible and offers, besides CO₂ free combustion, a significant reduction of NOₓ emissions compared to kerosene operation.
KW  - emission index
KW  - nitric oxides
KW  - aircraft engine
KW  - Micromix
KW  - combustion
KW  - hydrogen
Y1  - 2023
SN  - 978-0-7918-8693-9
U6  - http://dx.doi.org/10.1115/GT2023-102370
N1  - Paper No. GT2023-102370, V001T01A022
PB  - ASME
CY  - New York
ER  - 
TY  - CHAP
A1  - Bührig-Polaczek, Andreas
A1  - Röth, Thilo
A1  - Baumeister, E.
A1  - Nowack, N.
A1  - Süßmann, Torsten
T1  - Hybride Leichtbaustrukturen in Stahlblech-Leichtmetall Verbundguss
N2  - Stahl-Leichtmetall-Hybride mit hohen Leistungspotentialen können heute wirtschaftlich abgebildet werden und eignen sich möglicherweise auch zum Einsatz in Fahrzeugkarosserien
KW  - Karosseriebau
KW  - Verbundguss
KW  - Stahlblech-Leichtmetall Verbundguss
KW  - Stahlblech-Leichtmetall-Hybride
KW  - Lightweight car body construction
Y1  - 2006
ER  - 
TY  - CHAP
A1  - Peterson, Leif Arne
A1  - Röth, Thilo
A1  - Uibel, Thomas
ED  - Uibel, Thormas
ED  - Peterson, Leif Arne
ED  - Baumann, Marcus
T1  - Holzwerkstoffe in Karosseriestrukturen
T2  - Tagungsband Aachener Holzbautagung 2017
Y1  - 2017
SN  - 2197-4489
SP  - 34
EP  - 45
ER  - 
TY  - CHAP
A1  - Quitter, Julius
A1  - Marino, Matthew
A1  - Bauschat, J.-Michael
T1  - Highly Non-Planar Aircraft Configurations: Estimation of Flight Mechanical Derivatives Using Low-Order Methods
T2  - Deutscher Luft- und Raumfahrtkongress 2019, DLRK 2019. Darmstadt, Germany
Y1  - 2019
ER  - 
TY  - CHAP
A1  - Haugg, Albert Thomas
A1  - Kreyer, Jörg
A1  - Kemper, Hans
A1  - Hatesuer, Katerina
A1  - Esch, Thomas
T1  - Heat exchanger for ORC. adaptability and optimisation potentials
T2  - IIR International Rankine 2020 Conference
N2  - The recovery of waste heat requires heat exchangers to extract it from a liquid or gaseous medium into another working medium, a refrigerant. In Organic Rankine Cycles (ORC) on Combustion Engines there are two major heat sources, the exhaust gas and the water/glycol fluid from the engine’s cooling circuit. A heat exchanger design must be adapted to the different requirements and conditions resulting from the heat sources, fluids, system configurations, geometric restrictions, and etcetera. The Stacked Shell Cooler (SSC) is a new and very specific design of a plate heat exchanger, created by AKG, which allows with a maximum degree of freedom the optimization of heat exchange rate and the reduction of the related pressure drop. This optimization in heat exchanger design for ORC systems is even more important, because it reduces the energy consumption of the system and therefore maximizes the increase in overall efficiency of the engine.
Y1  - 2020
U6  - http://dx.doi.org/10.18462/iir.rankine.2020.1224
N1  - Conference: IIR International Rankine 2020 Conference - Heating, Cooling, Power Generation. Glasgow, 2020.
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
A1  - Kahle, Ralph
A1  - Wie, Bong
T1  - Head-on impact deflection of NEAs: a case study for 99942 Apophis
T2  - Planetary Defense Conference 2007
N2  - Near-Earth asteroid (NEA) 99942 Apophis provides a typical example for the evolution of asteroid orbits that lead to Earth-impacts after a close Earth-encounter that results in a resonant return. Apophis will have a close Earth-encounter in 2029 with potential very close subsequent Earth-encounters (or even an impact) in 2036 or later, depending on whether it passes through one of several less than 1 km-sized gravitational keyholes during its 2029-encounter. A pre-2029 kinetic impact is a very favorable option to nudge the asteroid out of a keyhole. The highest impact velocity and thus deflection can be achieved from a trajectory that is retrograde to Apophis orbit. With a chemical or electric propulsion system, however, many gravity assists and thus a long time is required to achieve this. We show in this paper that the solar sail might be the better propulsion system for such a mission: a solar sail Kinetic Energy Impactor (KEI) spacecraft could impact Apophis from a retrograde trajectory with a very high relative velocity (75-80 km/s) during one of its perihelion passages. The spacecraft consists of a 160 m × 160 m, 168 kg solar sail assembly and a 150 kg impactor. Although conventional spacecraft can also achieve the required minimum deflection of 1 km for this approx. 320 m-sized object from a prograde trajectory, our solar sail KEI concept also allows the deflection of larger objects. For a launch in 2020, we also show that, even after Apophis has flown through one of the gravitational keyholes in 2029, the solar sail KEI concept is still feasible to prevent Apophis from impacting the Earth, but many KEIs would be required for consecutive impacts to increase the total Earth-miss distance to a safe value
Y1  - 2007
N1  - Planetary Defense Conference 2007, Wahington D.C., USA, 05-08 March 2007
SP  - 1
EP  - 12
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  - 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  - Roosen, Petra
A1  - Feyerl, Günter
T1  - Gender-specific perception and utilization of personal use vehicles
T2  - FISITA World Automotive Congress 2014 : Maastricht, The Netherlands, 2 - 6 June / [organised by the International Federation of Automotive Engineering Societies (FISITA) ...]. Bd. 1
Y1  - 2015
SN  - 978-1-5108-0209-4
SP  - 418
EP  - 425
PB  - Curran
CY  - Red Hook, NY
ER  - 
TY  - CHAP
A1  - Lao, B.
A1  - Bührig-Polaczek, A.
A1  - Röth, Thilo
ED  - Wielage, Bernhard
T1  - Funktionsintegrierte Leichtbaustrukturen in gussintensiver Metall-Hybridbauweise
T2  - Verbundwerkstoffe und Werkstoffverbunde: Tagungsband zum 18. Symposium ; 30.03.2011 bis 01.04.2011, Chemnitz
Y1  - 2011
SN  - 978-3-00-033801-4
N1  - Schriftenreihe Werkstoffe und werkstofftechnische Anwendungen ; 41
SP  - 413
EP  - 421
PB  - Eigenverlag
CY  - Chemnitz
ER  - 
TY  - CHAP
A1  - Götten, Falk
A1  - Finger, Felix
A1  - Havermann, Marc
A1  - Braun, Carsten
A1  - Marino, Matthew
A1  - Bil, Cees
T1  - Full Configuration Drag Estimation of Small-to-Medium Range UAVs and its Impact on Initial Sizing Optimization
T2  - Deutscher Luft- und Raumfahrtkongress - DLRK 2020
Y1  - 2020
ER  - 
TY  - CHAP
A1  - Grundmann, Jan Thimo
A1  - Bauer, Waldemar
A1  - Biele, Jens
A1  - Cordero, Frederico
A1  - Dachwald, Bernd
A1  - Koncz, Alexander
A1  - Krause, Christian
A1  - Mikschl, Tobias
A1  - Montenegro, Sergio
A1  - Quantius, Dominik
A1  - Ruffer, Michael
A1  - Sasaki, Kaname
A1  - Schmitz, Nicole
A1  - Seefeldt, Patric
A1  - Tóth, Norbert
A1  - Wejmo, Elisabet
T1  - From Sail to Soil – Getting Sailcraft Out of the Harbour on a Visit to One of Earth’s Nearest Neighbours
T2  - 4th IAA Planetary Denfense Conference - PDC 2015,  13-17 April 2015, Frascati, Roma, Italy
Y1  - 2015
ER  - 
TY  - CHAP
A1  - Barnat, Miriam
A1  - Mergner, Julia
T1  - Forschungsbasierte Qualitätsentwicklung am Beispiel der Analyse von Lernprozessen und der Wirksamkeit von Förderprogrammen
T2  - 3. Internationale Tagung für Qualitätsmanagement und Qualitätsentwicklung im Hochschulbereich 2.-3. Februar 2017
Y1  - 2017
ER  - 
TY  - CHAP
A1  - Olaru, Alexandra Maria
A1  - Kowalski, Julia
A1  - Sethi, Vaishali
A1  - Blümich, Bernhard
T1  - Fluid Transport in Porous Media probed by Relaxation-Exchange NMR
T2  - 2011 Fall Meeting, AGU, San Francisco, Calif., 5-9 Dec.
Y1  - 2011
N1  - H12B-07; American Geophysical Union
ER  - 
TY  - CHAP
A1  - Grundmann, Jan Thimo
A1  - Bauer, Waldemar
A1  - Boden, Ralf
A1  - Ceriotti, Matteo
A1  - Chand, Suditi
A1  - Cordero, Federico
A1  - Dachwald, Bernd
A1  - Dumont, Etienne
A1  - Grimm, Christian D.
A1  - Heiligers, Jeannette
A1  - Herčík, David
A1  - Hérique, Alain
A1  - Ho, Tra-Mi
A1  - Jahnke, Rico
A1  - Kofman, Wlodek
A1  - Lange, Caroline
A1  - Lichtenheldt, Roy
A1  - McInnes, Colin
A1  - Meß, Jan-Gerd
A1  - Mikschl, Tobias
A1  - Mikulz, Eugen
A1  - Montenegro, Sergio
A1  - Moore, Iain
A1  - Pelivan, Ivanka
A1  - Peloni, Alessandro
A1  - Plettemeier, Dirk
A1  - Quantius, Dominik
A1  - Reershemius, Siebo
A1  - Renger, Thomas
A1  - Riemann, Johannes
A1  - Rogez, Yves
A1  - Ruffer, Michael
A1  - Sasaki, Kaname
A1  - Schmitz, Nicole
A1  - Seboldt, Wolfgang
A1  - Seefeldt, Patric
A1  - Spietz, Peter
A1  - Spröwitz, Tom
A1  - Sznajder, Maciej
A1  - Tóth, Norbert
A1  - Vergaaij, Merel
A1  - Viavattene, Giulia
A1  - Wejmo, Elisabet
A1  - Wiedemann, Carsten
A1  - Wolff, Friederike
A1  - Ziach, Christian
T1  - Flights are ten a sail – Re-use and commonality in the design and system engineering of small spacecraft solar sail missions with modular hardware for responsive and adaptive exploration
T2  - 70th International Astronautical Congress (IAC)
KW  - system engineering
KW  - small solar system body characterisation
KW  - small spacecraft solar sail
KW  - small spacecraft asteroid lander
KW  - responsive space
Y1  - 2019
SN  - 9781713814856
N1  - 70th International Astronautical Congress (IAC), Washington D.C., United States, 21-25 October 2019
SP  - 1
EP  - 7
ER  - 
TY  - CHAP
A1  - Ohndorf, Andreas
A1  - Dachwald, Bernd
A1  - Seboldt, Wolfgang
A1  - Schartner, Karl-Heinz
T1  - Flight times to the heliopause using a combination of solar and radioisotope electric propulsion
T2  - 32nd International Electric Propulsion Conference
N2  - We investigate the interplanetary flight of a low-thrust space probe to the heliopause,located at a distance of about 200 AU from the Sun. Our goal was to reach this distance within the 25 years postulated by ESA for such a mission (which is less ambitious than the 15-year goal set by NASA). Contrary to solar sail concepts and combinations of allistic and electrically propelled flight legs, we have investigated whether the set flight time limit could also be kept with a combination of solar-electric propulsion and a second, RTG-powered upper stage. The used ion engine type was the RIT-22 for the first stage and the RIT-10 for the second stage. Trajectory optimization was carried out with the low-thrust optimization program InTrance, which implements the method of Evolutionary Neurocontrol,using Artificial Neural Networks for spacecraft steering and Evolutionary Algorithms to optimize the Neural Networks’ parameter set. Based on a parameter space study, in which the number of thrust units, the unit’s specific impulse, and the relative size of the solar power generator were varied, we have chosen one configuration as reference. The transfer time of this reference configuration was 29.6 years and the fastest one, which is technically
more challenging, still required 28.3 years. As all flight times of this parameter study were longer than 25 years, we further shortened the transfer time by applying a launcher-provided hyperbolic excess energy up to 49 km2/s2. The resulting minimal flight time for the reference configuration was then 27.8 years. The following, more precise optimization to a launch with the European Ariane 5 ECA rocket reduced the transfer time to 27.5 years. This is the fastest mission design of our study that is flexible enough to allow a launch every
year. The inclusion of a fly-by at Jupiter finally resulted in a flight time of 23.8 years,which is below the set transfer-time limit. However, compared to the 27.5-year transfer,this mission design has a significantly reduced launch window and mission flexibility if the
escape direction is restricted to the heliosphere’s “nose".
KW  - low-thrust trajectory optimization
KW  - heliosphere
KW  - ion propulsion
Y1  - 2011
N1  - IEPC-2011-051
32nd International Electric Propulsion Conference,September 11–15, 2011
Wiesbaden, Germany
SP  - 1
EP  - 12
ER  - 
TY  - CHAP
A1  - Schildt, P.
A1  - Braun, Carsten
A1  - Marcocca, P.
T1  - Flight testing the extra 330LE flying testbed
T2  - 48th Annual International Symposium of the Society of Flight Test Engineers 2017
Y1  - 2017
SN  - 978-151085387-4
N1  - 48th Annual International Symposium of the Society of Flight Test Engineers 2017, SFTE 2017; Destin; United States; 30 October 2017 through 2 November 2017
SP  - 349
EP  - 362
ER  -