Dominik Quantius

Solar magnetism eXplorer (SolmeX)

The magnetic field plays a pivotal role in many fields of Astrophysics. This is especially true for the physics of the solar atmosphere. Measuring the magnetic field in the upper solar atmosphere is crucial to understand the nature of the underlying physical processes that drive the violent dynamics of the solar corona—that can also affect life on Earth. SolmeX, a fully equipped solar space observatory for remote-sensing observations, will provide the first comprehensive measurements of the strength and direction of the magnetic field in the upper solar atmosphere. The mission consists of two spacecraft, one carrying the instruments, and another one in formation flight at a distance of about 200 m carrying the occulter to provide an artificial total solar eclipse. This will ensure high-quality coronagraphic observations above the solar limb. SolmeX integrates two spectro-polarimetric coronagraphs for off-limb observations, one in the EUV and one in the IR, and three instruments for observations on the disk. The latter comprises one imaging polarimeter in the EUV for coronal studies, a spectro-polarimeter in the EUV to investigate the low corona, and an imaging spectro-polarimeter in the UV for chromospheric studies. SOHO and other existing missions have investigated the emission of the upper atmosphere in detail (not considering polarization), and as this will be the case also for missions planned for the near future. Therefore it is timely that SolmeX provides the final piece of the observational quest by measuring the magnetic field in the upper atmosphere through polarimetric observations.

Decision Support Tool for Concurrent Engineering in Space Mission Design

The concurrent engineering (CE) approach has been successfully applied to the early design phase of space missions. During CE sessions, a software support is needed to allow multidisciplinary design data exchange. At the moment, a spreadsheet-based solution enhanced with macros is used at the German Aerospace Center (DLR) to create a system model of a space mission during the early design phase. Now there is an increasing demand to take advantage of this system model and provide data analysis features which improve the decision making during CE sessions. Since the current approach is limited for such analysis, DLR has started developing a new tool called Virtual Satellite. It offers extended software support required by the Concurrent Engineering Facility of DLR in Bremen. On top of the previous spreadsheet functionalities, it provides means for online data analysis and system modeling. The results of these data analyses are presented to the discipline experts using different views which help in performing an early design optimization. In this paper, the impact of these views on the decision making during the AEGIS space mission study is presented as a proof of concept.

Interactions in space systems design within a Concurrent Engineering facility

Concurrent Engineering (CE) in the space sector is an effective collaborative development approach for space mission architectures or system design. It involves each appropriate discipline and follows a structured process which guides the team through the early phases of the product life-cycle. Furthermore, integrated design models and domain specific tools support the engineers in generating and exchanging design parameters. As is often misunderstood, Concurrent Engineering is not a design optimization performed by advanced software, but is a team effort where the product development is supported by tools but decisions still made by people. During feasibility studies of space craft design within the “Concurrent Engineering Facility (CEF)” of the German Aerospace Center (DLR) there is a certain set-up of domains each dealing with their respective hard- and software tools. Within the present paper the cases of human-to-human and human-to-machine interaction during the iterative design process is discussed. The focus is set on the interaction between and within the different parties during both the plenary and off-line design sessions. The importance of guided communication and the value of specific and common tool utilization is pointed out. Furthermore, the challenges, constraints, potential improvements and stumbling blocks are identified when dealing with a heterogeneous team of experts in such early design phases.

Potential of hybridisation of the thermochemical hybrid-sulphur cycle for the production of hydrogen by using nuclear and solar energy in the same plant

The search for a sustainable, CO2-free massive hydrogen production route is a strong need, if one takes into account the world-wide increasing energy demand, the deterioration of fossil fuel reserves and in particular the increasing CO2 concentration leading to global warming. Thermo-chemical cycles for water splitting are considered as a promising alternative of emission-free routes of massive hydrogen production – with potentially higher efficiencies and lower costs compared to alkaline electrolysis of water. The hybrid-sulphur cycle was chosen as one of the most promising cycles from the ‘sulphur family’ of processes. Different process schemes using concentrated sunlight or nuclear generated heat or a combination of both have been elaborated and analysed by a comparative techno-economic study with regard to their potential of a large-scale hydrogen production. Options for a hybridisation of the energy supply between solar and nuclear have been also investigated, particular focused on the coupling of concentrated solar radiation into a round-the-clock operated process. Process design and simulation, industrial scale-up assessments including safety analysis and cost evaluations were performed to analyse reliability and potential of those process concepts.

Conceptual data model: A foundation for successful concurrent engineering

Today, phase A studies of future space systems are often conducted in special design facilities such as the Concurrent Engineering Facility at the German Aerospace Center (DLR). Within these facilities, the studies are performed following a defined process making use of a data model for information exchange. Quite often it remains unclear what exactly such a data model is and how it is implemented and applied. Nowadays, such a data model is usually a software using a formal specification describing its capabilities within a so-called meta-model. This meta-model, often referred as conceptual data model, is finally used and instantiated as system model during these concurrent engineering studies. Such software also provides a user interface for instantiating and sharing the system model within the design team and it provides capabilities to analyze the system model on the fly. This is possible due to the semantics of the underlying conceptual data model creating a common language used to exchange and process design information. This article explains the implementation of the data model at DLR and shows information how it is applied in the concurrent engineering process of the Concurrent Engineering Facility. It highlights important aspects concerning the modeling capabilities during a study and discusses how they can be implemented into a corresponding conceptual data model. Accordingly, the article presents important aspects such as rights management and data consistency and the implications of them to the software’s underlying technology. A special use case of the data model is depicted and shows the flexibility of the implementation proven by a study of a multi-module space station.