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Small satellites contribute significantly in the rapidly evolving innovation in space engineering, in particular in distributed space systems for global Earth observation and communication services. Significant mass reduction by miniaturization, increased utilization of commercial high-tech components, and in particular standardization are the key drivers for modern miniature space technology. This thesis addresses key fields in research and development on miniature satellite technology regarding efficiency, flexibility, and robustness. Here, these challenges are addressed by the University of Wuerzburg's advanced pico-satellite bus, realizing a generic modular satellite architecture and standardized interfaces for all subsystems. The modular platform ensures reusability, scalability, and increased testability due to its flexible subsystem interface which allows efficient and compact integration of the entire satellite in a plug-and-play manner. Beside systematic design for testability, a high degree of operational robustness is achieved by the consequent implementation of redundancy of crucial subsystems. This is combined with efficient fault detection, isolation and recovery mechanisms. Thus, the UWE-3 platform, and in particular the on-board data handling system and the electrical power system, offers one of the most efficient pico-satellite architectures launched in recent years and provides a solid basis for future extensions. The in-orbit performance results of the pico-satellite UWE-3 are presented and summarize successful operations since its launch in 2013. Several software extensions and adaptations have been uploaded to UWE-3 increasing its capabilities. Thus, a very flexible platform for in-orbit software experiments and for evaluations of innovative concepts was provided and tested. ; Miniaturisierte Satellitensysteme übernehmen zunehmend eine entscheidende Rolle in der fortschreitenden Globalisierung und Demokratisierung der Raumfahrt. Großes Innovationspotential und neue Kommerzialisierungschancen verspricht der effektive Einsatz von Kleinstsatelliten in zukünftigen fraktionierten Missionen für Erdbeobachtungs- und Kommunikationsanwendungen. Basierend auf vielen kleinen kooperierenden Systemen können diese Systeme zukünftig große multifunktionale Satelliten ergänzen oder ersetzen. Die Herausforderung bei der Entwicklung miniaturisierter Satellitensysteme ist die Gratwanderung zwischen der im Rahmen der Miniaturisierung notwendigen Effizienz, der für die Erfüllung der Mission geforderten Zuverlässigkeit und der wünschenswerten Wiederverwendbarkeit und Erweiterbarkeit zur Realisierung agiler Kleinstsatellitenserien. Diese Arbeit adressiert verschiedene Aspekte für den optimalen Entwurf robuster, flexibler und effizienter Kleinstsatelliten am Beispiel des UWE Pico-Satelliten Bus der Universität Würzburg. Mit dem Ziel der Entwicklung einer soliden Basisplattform für zukünftige Kleinstsatelliten-Formationen wurden entsprechende Designansätze im Rahmen des UWE-3 Projektes in einem integralen Designansatz konsistent umgesetzt. Neben der Entwicklung von effizienten Redundanzkonzepten mit minimalem Overhead für den optimalen Betrieb auf Ressourcen-limitierten Kleinstsatelliten wurde ein modularer Satellitenbus entworfen, der als eine robuste und erweiterbare Basis für zukünftige Missionen dienen soll. Damit realisiert UWE-3 eine der effizientesten Kleinstsatelliten-Architekturen die in den letzten Jahren in den Orbit gebracht wurde. Dargestellte Missionsergebnisse fassen den erfolgreichen Betrieb des Satelliten seit seinem Launch in Jahr 2013 zusammen.

Contributor(s): Stephan Chambers, Dr Christian Busch, Dr Juli Huang, Dr Jason Hickel | Welcome to LSE IQ, a new monthly podcast from the London School of Economics and Political Science. This is the podcast where we ask some of the leading social scientists - and other experts - to answer intelligent questions about economics, politics or society. Over the last couple of decades Western aid agencies, the World Bank, NGOs and business schools have all enthusiastically embraced the concept of social entrepreneurship. This takes the methods and energy of business entrepreneurship and applies them to often intractable social, or environmental, problems. Social enterprises hold the promise of developing financially sustainable solutions and of providing dignity, rather than just charity, for those they seek to help. In this episode of LSE IQ, Sue Windebank asks, 'Could social entrepreneurship be the answer to world poverty?' This episode features: Dr Christian Busch, researcher, LSE Innovation Co-Creation Lab; Stephan Chambers, Director, Marshall Institute for Philanthropy and Social Entrepreneurship; Dr Jason Hickel, Fellow, LSE Department of Anthropology and; Dr Juli Huang, Lecturer in Anthropology of Development, The University of Edinburgh. For further information about the podcast visit lse.ac.uk/iq and please tell us what you think using the hashtag #LSEIQ.

The ERNST (Experimental Spacecraft based on Nanosatellite Technology) mission is both a mid-wavelength infrared imaging satellite as well as a technology demonstrator. The 12 U nanosatellite is based on off-the-shelf CubeSat components where appropriate parts are available. All other subsystems and especially the main payloads are designed and built by Fraunhofer. The overall mission goal is to evaluate the utility of a large nanosatellite mission for scientific and military purposes. ERNST's primary payload is a high-resolution mid-wavelength-infrared camera that is actively cooled by a Stirling cryo-cooler. This payload generates very demanding requirements for the satellite bus and exceeds the capabilities that are normally associated with CubeSats. This payload also demonstrates on-board data-processing using state-of-the-art FPGA technology and comprises a filter pendulum mechanism for switching between several spectral bands. The payload data is transmitted to the ground segment in X-Band. All components of this payload are mounted on an optical bench which has been designed using numerical topology optimization methods and is 3D-printed from an aluminum alloy. Integrated into this optical bench is a 3D-structured radiator that dissipates the heat generated by the cryo-cooler. The second payload is a radiation sensor by Fraunhofer INT that characterizes the radiation environment in ERNST's orbit by measuring electrons and protons from the radiation belts and from solar storms. The radiation sensing is based solely on counting the number of changed bits in memory devices behind different shielding thicknesses to distinguish between different types of particles and energies. Furthermore, ERNST hosts an optical camera payload in the visual spectrum. The ERNST 12U platform provides flexible payload capabilities with high-data rate processing and download, as well as 60 W beginning-of-life power provided by two deployable solar arrays. The most complex mechanism on board is a drag-sail subsystem to de-orbit the ERNST nanosatellite after its mission end for ensuring the sustainability of space applications.