Universitatsallee 27 29
Universitatsallee 27 29
Van Der Veen E.J.,Universitatsallee 27 29 |
Perez G.,Universitatsallee 27 29 |
Sabbatinelli B.,Universitatsallee 27 29
Proceedings of the International Astronautical Congress, IAC | Year: 2016
Within this paper an overview of the tools and mechanisms is given used by OHB System to manage internal and external innovations. OHB has grown within a few years from an SME status to the third largest Lead System Integrator (LSI) in Europe. Trigger for this was the very successful management of the German Bundeswehr Radar surveillance satellite constellation (6 LEO satellites) SAR-Lupe. This place OHB in a unique position to bid and surprising to most win, the first and second batch of Europe's GNSS satellite system Galileo (22 MEO satellites). This line of success continued with several Telecommunication- (Hispasat AG1, EDRS-C and the Electra all-electric platform) and Earth observation satellites (EnMap SARah). OHB owes most of its success in the recent years to empowering employees and letting them actively propose and manage new innovations and business lines. This approach works especially well in OHB's unique company culture with flexible processes and a flat-hierarchy, due to it being a family owned company. This has resulted to a very innovative way of designing and building satellites such as: • A highly modular satellite design encouraging suppliers to cooperate in the design on a system level • Serial production methods allowing for cost reductions in the production process (experience from the Galileo constellation) • High degree of cooperation with SMEs and Research institutes in order in foster innovations This paper will show how OHB's staff are given incentives for introducing new ideas and how an active market outlook leads to the fostering of innovations through the company. In order to keep fostering new ideas, a number of methods are applied which will be explained in the paper: • Employee innovation prices • Bottom-up innovation pull • Top-down innovation push • Rigorous technology roadmapping practices • Market outlook and business plans • Disruptive technology searches • Supplier industry days • Quick innovation assessment brainstorming sessions Currently these practices have resulted in several cutting edge innovations developing in rapid cycles which differentiates us to some extend from our competitors (e.g. all-electric satellites, additive manufacturing processes, advanced avionics solutions based on optical fibers, highly modular panel design, advanced thermal management solutions) In the end, this paper concludes with giving some recommendations for companies looking to manage their innovation process and extend an open invitation to get involved within the OHB innovation process. Copyright © 2016 by the International Astronautical Federation (IAF). All rights reserved.
Gibbings A.,Universitatsallee 27 29 |
Bowles N.,University of Oxford |
Snodgrass C.,Open University Milton Keynes |
Sanchez J.P.,Cranfield University |
And 2 more authors.
Proceedings of the International Astronautical Congress, IAC | Year: 2016
A consortium of international scientists and industry partners are proposing the Main Belt Inventory Mission as a candidate in the next forthcoming ESA medium class mission call. The inventory mission will characterise a broad range of statistically significant asteroid samples throughout the Main Asteroid Belt (MAB). A 0.5 m aperture space-based telescope will conduct a detailed spectroscopic survey, observing thousands of objects from a range of 0.1-0.5 AU, and perform basic flybys of pre-selected targets. Each flyby will target an asteroid of a different size, taxonomic (sub)classes and orbital families, where spatially resolved spectral mapping and spectroscopy will be performed. Smaller and fainter passing targets will also be discovered, through opportunistic science, with dedicated star tracker-like cameras. Examining the compositional diversity across the asteroid population will provide a key tracer to understanding the dynamic evolution of the solar system, offer an insight into its early history and the origins of life forming material. Furthermore, by combing visible, near-infrared and thermal spectroscopy, the mission will unlock information on the major rock forming minerals, hydrated minerals, organics and primitive material found throughout the asteroid belt. Coarse UV mapping capability will search for weak OH emission bands, providing evidence of buried volatile (water) reservoirs. This will provide an additional link to fully understanding the meteorite record on Earth, and more importantly, place the returned samples from the up-and-coming Hayabusa-2 (JAXA) and OSIRIS-REx (NASA) missions in a wider geological context. The mission will provide an accurate description of the present day MAB population, and further refinements of the origins and evolution models of Near Earth Asteroids. This paper will report on the scientific justification and focus on the (sub-)system spacecraft design to perform a detailed inventory mission of the MAB. It includes an evaluation of the different system options and architecture designs. The baseline design is then presented, and further broken down for each subsystem. The science and mission objectives have been developed within the scope of the expected boundary conditions of the forthcoming ESA medium class mission call. It therefore necessitates a high TRL spacecraft, ready for launch within the 2028/32 timeframe on either a Vega-C (or Ariane 6) launch vehicle. The mission and system design is currently being developed through an ongoing mission study. Analysis is performed by a consortium of OHB System AG, Cranfield University and an association of scientists from different institutes and organisations. Concurrent engineering techniques are used throughout. Copyright © 2016 by the author's organization All rights reserved.
Braukhane A.,Universitatsallee 27 29 |
Gerth I.,Universitatsallee 27 29 |
Homeister M.,Universitatsallee 27 29 |
Rohrbeck M.,Universitatsallee 27 29
Proceedings of the International Astronautical Congress, IAC | Year: 2016
Due to the characteristics of Earth's magnetic field, there are several accessible regions of turbulent magnetized plasma. Hot plasma is considered as a main origin of electromagnetic radiation and its measurement is fundamental for our knowledge of the Universe. Hence, the direct investigation of the turbulent energy dissipation and plasma energization is key for a better understanding of plasma physics and the underlying physical mechanisms, which is still very limited. In order to answer the connected scientific questions, ESA selected the proposed Turbulence Heating Observer (THOR) as a candidate for the 4th ESA medium-class science mission within the Cosmic Vision 2015-2025 programme. The THOR mission is currently undergoing the definition phase with a launch date planned for 2026, and an envisaged nominal operational lifetime of 3.5 years. The desired time in the regions of interest (i.e. within Earth's magnetosheath, bowshock, foreshock and pristine solar wind environment) and the related highly-elliptical orbits as well as the scientific payload impose stringent requirements on the mission architecture and system design, which are carefully traded very early in the project. These trades include amongst others the orbit injection approach, the transfer scenarios to access the relevant science orbits with apogees of up to 70 Earth radii, and the interlinked system aspects, such as appendage dynamics, radiation and electromagnetic shielding. The ten different payloads, including magnetometers, particle analyzers and electric field instruments, are accommodated on a spin-stabilized spacecraft which is equipped with two approximately 6 meter rigid and four 50 meter wire booms, carrying some of the instruments. This particular configuration is mainly needed due to the required measurement accuracy, radiation and electromagnetic compatibility (EMC) issues, and closely interdependent with the THOR maneuver strategy, spacecraft modes as well as component placement and shielding. This paper describes the driving requirements and the results of all major mission- and system-trades performed by OHB System and its consortium, including a discussion on the Ariane 6.2 and Soyuz launch vehicle capabilities and how they affect and create subsequent options and trades. The presented work furthermore contains a summary of the baseline mission and system architecture and concludes with an outlook of the on-going analysis required to make this interesting mission a reality. Copyright © 2016 by the International Astronautical Federation (IAF). All rights reserved.
McInnes C.R.,University of Strathclyde |
Bewick R.,Universitatsallee 27 29 |
Sanchez J.P.,Polytechnic University of Catalonia
Issues in Environmental Science and Technology | Year: 2014
This chapter provides an overview of space-based geoengineering as a tool to modulate solar insolation and offset the impacts of humandriven climate change. A range of schemes are considered including static and orbiting occulting disks and artificial dust clouds at the interior Sun-Earth Lagrange point, the gravitational balance point between the Sun and Earth. It is demonstrated that, in principle, a dust cloud can be gravitationally anchored at the interior Lagrange point to reduce solar insolation and that orbiting disks can provide a uniform reduction of solar insolation with latitude, potentially offsetting the regional impacts of a static disk. While clearly speculative, the investigation of space-based geoengineering schemes provides insights into the long-term prospects for large-scale, active control of solar insolation. © The Royal Society of Chemistry 2014.
Wagner I.,Karlsruhe Institute of Technology |
Braun M.,Universitatsallee 27 29 |
Slenzka K.,German Aerospace Center |
Posten C.,Karlsruhe Institute of Technology
Advances in Biochemical Engineering/Biotechnology | Year: 2016
Life support systems for long-term space missions or extraterrestrial installations have to fulfill major functions such as purification of water and regeneration of atmosphere as well as the generation of food and energy. For almost 60 years ideas for biological life support systems have been collected and various concepts have been developed and tested. Microalgae as photosynthetic organisms have played a major role in most of these concepts. This review deals with the potentials of using eukaryotic microalgae for life support systems and highlights special requirements and frame conditions for designing space photobioreactors especially regarding illumination and aeration. Mono- and dichromatic illumination based on LEDs is a promising alternative for conventional systems and preliminary results yielded higher photoconversion efficiencies (PCE) for dichromatic red/blue illumination than white illumination. Aeration for microgravity conditions should be realized in a bubble-free manner, for example, via membranes. Finally, a novel photobioreactor concept for space application is introduced being parameterized and tested with the microalga Chlamydomonas reinhardtii. This system has already been tested during two parabolic flight campaigns. © Springer International Publishing Switzerland 2015.
Panopoulou A.,Universitatsallee 27 29 |
Fransen S.,European Space Agency |
Gomez-Molinero V.,Airbus |
Kostopoulos V.,University of Patras
CEAS Space Journal | Year: 2013
The objective of this work is to develop a new structural health monitoring system for composite aerospace structures based on dynamic response strain measurements and experimental modal analysis techniques. Fiber Bragg grating (FBG) optical sensors were used for monitoring the dynamic response of the composite structure. The structural dynamic behavior has been numerically simulated and experimentally verified by means of vibration testing. The hypothesis of all vibration tests was that actual damage in composites reduces their stiffness and produces an eigenfrequency shifting to lower values in the same sense as mass increase produces. Thus, damage was simulated by slightly varying locally the mass of the structure at different zones. The correlation between the simulated damage and the loss of stiffness was analytically defined. Experimental modal analysis based on the strain responses was conducted and the extracted strain mode shapes were the input for the damage detection expert system. A feed-forward back propagation neural network was the core of the damage detection system. The features-input to the neural network consisted of the strain mode shapes, extracted from the experimental modal analysis. Dedicated training and validation activities were carried out based on the experimental results. The system showed high reliability, confirmed by the ability of the neural network to recognize the size and the position of damage on the structure. The experiments were performed on a real structure i.e. a lightweight antenna sub-reflector, manufactured and tested at EADS CASA ESPACIO. An integrated FBG sensor network, based on the advantage of multiplexing, was mounted on the structure with optimum topology. Numerical simulation was used as a support tool at all the steps of the work. Potential applications for the proposed system are during ground qualification extensive tests of space structures and during the mission as modal analysis tool on board, being able via the FBG responses to identify a potential failure. © 2013 CEAS.
Heinkelmann R.,Deutsches Geodatisches Forschungsinstitut DGFI |
Tesmer V.,Universitatsallee 27 29
International Association of Geodesy Symposia | Year: 2013
We assess the systematics between Very Long Baseline Interferometry (VLBI) terrestrial and celestial reference frames (TRF and CRF) solutions caused by different analysis options. Comparisons are achieved by sequential variation of options relative to a reference solution, which fulfills the requirements of the International VLBI Service for Geodesy and Astrometry (IVS) analysis coordination. Neglecting the total NASA/GSFC Data Assimilation Office (DAO) a priori gradients causes the largest effects: Mean source declinations differ up to 0.2 mas, station positions are shifted southwards, and heights are systematically larger by up to 3 mm, if no a priori gradients are applied. The effect is explained with the application of gradient constraints. Antenna thermal deformations, atmospheric pressure loading, and the atmosphere pressure used for hydrostatic delay modeling still exhibit significant effects on the TRF, but corresponding CRF differences (about 10 mas) are insignificant. The application of NMF atmosphere mapping functions can systematically affect source declinations up to 30 mas, which is between the estimated axes stability (10 μas) and the mean positional accuracy (40 μas) specified for the ICRF2. Further significant systematic effects are seasonal variations of the terrestrial network scale (±1 mm) neglecting antenna thermal deformations, and seasonal variations of station positions, primarily of the vertical component up to 5 mm, neglecting atmospheric loading. The application of NMF instead of VMF1 can result in differences of station heights up to 6 mm, but no overall global systematic can be found. Using constant atmosphere pressure values for the determination of hydrostatic zenith delays systematically deforms the TRF: station height differences mostly show the same sign with absolute values exceeding 1 mm. © Springer-Verlag Berlin Heidelberg 2013.
Wortmann A.,Universitatsallee 27 29 |
MacHel G.,Universitatsallee 27 29 |
Holsti N.,Tidorum Ltd.
European Space Agency, (Special Publication) ESA SP | Year: 2012
The application of modern object oriented design and modeling techniques on the basis of state charts aid modular and flexible software architectures. On the other hand, a satellite's on-board software drives an efficient embedded system that must satisfy a large number of (hard) real-time requirements. The on-board software of the Small Geo (SGEO) program is designed with a model based approach and the architecture is eventdriven. The challenge taken and presented in this paper is the successful timing verification of a real-time software with event-driven code auto-generated from state charts. Static worst case execution time analysis and feasibility calculations are presented for both hard-realtime-tasks and soft-real-time activities.
Pawlak H.,Universitatsallee 27 29 |
Jacob A.F.,TU Hamburg - Harburg
IEEE Transactions on Antennas and Propagation | Year: 2010
A novel calibration scheme is presented that is especially suited for complex digital beamforming (DBF) antenna arrays at millimeter-wave frequencies. Calibration data is extracted by sampling the field of each radiator at certain locations near the array by fixed probe antennas. A scalable calibration model for evaluation of the measured data is described. First tests are performed on a small passive array representing a unit cell of larger arrays. The calibration scheme is subsequently applied to and tested on a 64 element DBF transmit antenna array. © 2009 IEEE.
Tesmer V.,Universitatsallee 27 29 |
Steigenberger P.,TU Munich |
van Dam T.,University of Luxembourg |
Mayer-Gurr T.,University of Bonn
Journal of Geodesy | Year: 2011
Temporal variations in the geographic distribution of surface mass cause surface displacements. Surface displacements derived from GRACE gravity field coefficient time series also should be observed in GPS coordinate time series, if both time series are sufficiently free of systematic errors. A successful validation can be an important contribution to climate change research, as the biggest contributors to mass variability in the system Earth include the movement of oceanic, atmospheric, and continental water and ice. In our analysis, we find that if the signals are larger than their precision, both geodetic sensor systems see common signals for almost all the 115 stations surveyed. Almost 80% of the stations have their signal WRMS decreased, when we subtract monthly GRACE surface displacements from those observed by GPS data. Almost all other stations are on ocean islands or small peninsulas, where the physically expected loading signals are very small. For a fair comparison, the data (79 months from September 2002 to April 2009) had to be treated appropriately: the GPS data were completely reprocessed with state-of-the-art models. We used an objective cluster analysis to identify and eliminate stations, where local effects or technical artifacts dominated the signals. In addition, it was necessary for both sets of results to be expressed in equivalent reference frames, meaning that net translations between the GPS and GRACE data sets had to be treated adequately. These data sets are then compared and statistically analyzed: we determine the stability (precision) of GRACE-derived, monthly vertical deformation data to be ~1.2 mm, using the data from three GRACE processing centers. We statistically analyze the mean annual signals, computed from the GPS and GRACE series. There is a detailed discussion of the results for five overall representative stations, in order to help the reader to link the displayed criteria of similarity to real data. A series of tests were performed with the goal of explaining the remaining GPS-GRACE residuals. © 2011 Springer-Verlag.