Development and design of multifunctional lightweight structures for satellite applications

摘要

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 th