TY  - CHAP
A1  - Pirovano, Laura
A1  - Seefeldt, Patric
A1  - Dachwald, Bernd
A1  - Noomen, Ron
T1  - Attitude and orbital modeling of an uncontrolled solar-sail experiment in low-Earth orbit
T2  - 25th International Symposium on Space Flight Dynamics ISSFD
N2  - Gossamer-1 is the first project of the three-step Gossamer roadmap, the purpose of which is to develop, prove and demonstrate that solar-sail technology is a safe and reliable propulsion technique for long-lasting and high-energy missions. This paper firstly presents the structural analysis performed on the sail to understand its elastic behavior. The results are then used in attitude and orbital simulations. The model considers the main forces and torques that a satellite experiences in low-Earth orbit coupled with the sail deformation. Doing the simulations for varying initial conditions in attitude and rotation rate, the results show initial states to avoid and maximum rotation rates reached for correct and faulty deployment of the sail. Lastly comparisons with the classic flat sail model are carried out to test the hypothesis that the elastic behavior does play a role in the attitude and orbital behavior of the sail
KW  - Solar sail
KW  - Gossamer structures
KW  - Attitude dynamics
KW  - Orbital dynamics
Y1  - 2015
N1  - 25th International Symposium on Space Flight Dynamics ISSFD
October 19 – 23, 2015, Munich, Germany
https://issfd.org/2015/
SP  - 1
EP  - 15
ER  - 
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  - Seifarth, Volker
A1  - Goßmann, Matthias
A1  - Grosse, J. O.
A1  - Becker, C.
A1  - Heschel, I.
A1  - Artmann, Gerhard
A1  - Temiz Artmann, Aysegül
T1  - Development of a Bioreactor to Culture Tissue Engineered Ureters Based on the Application of Tubular OPTIMAIX 3D Scaffolds
JF  - Urologia Internationalis
Y1  - 2015
U6  - https://doi.org/10.1159/000368419
SN  - 0042-1138
VL  - 2015
IS  - 95
SP  - 106
EP  - 113
PB  - Karger
CY  - Basel
ER  - 
TY  - JOUR
A1  - Kowalski, Julia
A1  - Linder, Peter
A1  - Zierke, S.
A1  - Wulfen, B. van
A1  - Clemens, J.
A1  - Konstantinidis, K.
A1  - Ameres, G.
A1  - Hoffmann, R.
A1  - Mikucki, J.
A1  - Tulaczyk, S.
A1  - Funke, O.
A1  - Blandfort, D.
A1  - Espe, Clemens
A1  - Feldmann, Marco
A1  - Francke, Gero
A1  - Hiecker, S.
A1  - Plescher, Engelbert
A1  - Schöngarth, Sarah
A1  - Dachwald, Bernd
A1  - Digel, Ilya
A1  - Artmann, Gerhard
A1  - Eliseev, D.
A1  - Heinen, D.
A1  - Scholz, F.
A1  - Wiebusch, C.
A1  - Macht, S.
A1  - Bestmann, U.
A1  - Reineking, T.
A1  - Zetzsche, C.
A1  - Schill, K.
A1  - Förstner, R.
A1  - Niedermeier, H.
A1  - Szumski, A.
A1  - Eissfeller, B.
A1  - Naumann, U.
A1  - Helbing, K.
T1  - Navigation technology for exploration of glacier ice with maneuverable melting probes
JF  - Cold Regions Science and Technology
N2  - The Saturnian moon Enceladus with its extensive water bodies underneath a thick ice sheet cover is a potential candidate for extraterrestrial life. Direct exploration of such extraterrestrial aquatic ecosystems requires advanced access and sampling technologies with a high level of autonomy. A new technological approach has been developed as part of the collaborative research project Enceladus Explorer (EnEx). The concept is based upon a minimally invasive melting probe called the IceMole. The force-regulated, heater-controlled IceMole is able to travel along a curved trajectory as well as upwards. Hence, it allows maneuvers which may be necessary for obstacle avoidance or target selection. Maneuverability, however, necessitates a sophisticated on-board navigation system capable of autonomous operations. The development of such a navigational system has been the focal part of the EnEx project. The original IceMole has been further developed to include relative positioning based on in-ice attitude determination, acoustic positioning, ultrasonic obstacle and target detection integrated through a high-level sensor fusion. This paper describes the EnEx technology and discusses implications for an actual extraterrestrial mission concept.
Y1  - 2016
U6  - https://doi.org/10.1016/j.coldregions.2015.11.006
SN  - 0165-232X
IS  - 123
SP  - 53
EP  - 70
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Neu, Eugen
A1  - Janser, Frank
A1  - Khatibi, Akbar A.
A1  - Braun, Carsten
A1  - Orifici, Adrian C.
T1  - Operational Modal Analysis of a wing excited by transonic flow
JF  - Aerospace Science and Technology
N2  - Operational Modal Analysis (OMA) is a promising candidate for flutter testing and Structural Health Monitoring (SHM) of aircraft wings that are passively excited by wind loads. However, no studies have been published where OMA is tested in transonic flows, which is the dominant condition for large civil aircraft and is characterized by complex and unique aerodynamic phenomena. We use data from the HIRENASD large-scale wind tunnel experiment to automatically extract modal parameters from an ambiently excited wing operated in the transonic regime using two OMA methods: Stochastic Subspace Identification (SSI) and Frequency Domain Decomposition (FDD). The system response is evaluated based on accelerometer measurements. The excitation is investigated from surface pressure measurements. The forcing function is shown to be non-white, non-stationary and contaminated by narrow-banded transonic disturbances. All these properties violate fundamental OMA assumptions about the forcing function. Despite this, all physical modes in the investigated frequency range were successfully identified, and in addition transonic pressure waves were identified as physical modes as well. The SSI method showed superior identification capabilities for the investigated case. The investigation shows that complex transonic flows can interfere with OMA. This can make existing approaches for modal tracking unsuitable for their application to aircraft wings operated in the transonic flight regime. Approaches to separate the true physical modes from the transonic disturbances are discussed.
Y1  - 2016
U6  - https://doi.org/10.1016/j.ast.2015.11.032
SN  - 1270-9638
VL  - 49
SP  - 73
EP  - 79
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - CHAP
A1  - Funke, Harald
A1  - Keinz, Jan
A1  - Börner, S.
A1  - Hendrick, P.
A1  - Elsing, R.
T1  - Testing and analysis of the impact on engine cycle parameters and control system modifications using hydrogen or methane as fuel in an industrial gas turbine
T2  - Progress in propulsion physics ; Volume 8
Y1  - 2016
SN  - 978-5-94588-191-4
U6  - https://doi.org/10.1051/eucass/201608409
SP  - 409
EP  - 426
PB  - EDP Sciences
CY  - o.O.
ER  - 
TY  - CHAP
A1  - Wu, Ziyi
A1  - Kemper, Hans
T1  - The optimal 48 V – battery pack for a specific load profile of a heavy duty vehicle
T2  - 8. Internationale Fachtagung Kraftwerk Batterie : 26. – 27. April 2016, Münster, Deutschland
Y1  - 2016
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  - Barnat, Miriam
A1  - Bosse, Elke
T1  - The challenge of creating meta-inferences: Combining data representing institutional and individual perspectives on first-year support in higher education
T2  - 9th Conference on Social Science Methodology of the International Sociological Association, Leicester, UK
Y1  - 2016
N1  - RC33 Conference 2016
SP  - 1
EP  - 20
ER  - 
TY  - CHAP
A1  - Kleine, Harald
A1  - Kallweit, Stephan
A1  - Michaux, Frank
A1  - Havermann, Marc
A1  - Olivier, Herbert
T1  - PIV Measurement of Shock Wave Diffraction
T2  - 18th International Symposium on Applications of Laser Techniques to Fluid Mechanics, 2016, Lissabon
Y1  - 2016
SP  - 1
EP  - 14
ER  -