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Development and design of multifunctional lightweight structures for satellite applications

: Schubert, M.; Perfetto, S.; Dafnis, A.; Mayer, D.; Atzrodt, H.

International Astronautical Federation:
International Astronautical Congress, IAC 2018. Proceedings : Bremen, Germany 1 - 5 October 2018
Paris: International Astronautical Federation, 2018
ISSN: 0074-1795
2 S.
International Astronautical Congress (IAC) <69, 2018, Bremen>
Fraunhofer LBF ()

Within the framework of the German national project multiSat multifunctional composite structures for satellite applications are developed. The objective is the integration of passive and active functions into the load-bearing spacecraft structure by using suitable materials, components and mechanisms. The passive functions are heat transfer, radiation shielding and protection against orbital debris impact, whereas the active functions include vibration suppression and transmission of data and electrical energy. Composite materials and structures usually consist of multiple layers which makes them suitable for functional integration since each layer can be defined and designed to provide one or more specific functions. The concept of a multifunctional structure allows for the reduction of the overall satellite mass and of installation space required for subsystems. It also opens up new opportunities for highly integrative and standardized production processes and lower total costs and time for manufacturing, qualification and launch. Composite sandwich panels are investigated as representative structural components of a satellite. Based on a conceptual analysis, a design of a multifunctional composite sandwich panel is developed. Various materials and layups are investigated in order to implement the passive functions and enable the integration of tertiary structures for the active functions. The heat transfer within the structure is improved by the use of structural materials with high thermal conductivities and radiation shielding is enhanced by layers with high radiation absorption capability. Metallic lattice structures and high-strength fabrics are integrated into the core of the sandwich in order to effectively break up and slow down impacting debris particles. Vibration reduction is achieved by means of flat piezoelectric transducers bonded to the face sheets and connected to shunt circuits, whereas flat electric cables and optical fibres are embedded into the composite structure for the transmission of electrical energy and data. For the simulation of the vibration suppression finite element models with integrated piezoelectric transducers are implemented. The efficiency of various vibration control strategies and different shunt electric circuits is compared by means of reduced order modelling. Experimental tests at coupon level are conducted on sandwich panels and beams in order to verify the integration and the performance of the passive and active functions. In this paper the pursued multifunctional structural concepts and the results of the experiments are presented.