Multifunctional lightweight structures for satellitesCopyright: SLA
The primary structure of conventional satellites is usually designed mainly for supporting mechanical loads, providing attachment points for the subsystems and protecting them against the space environment. The subsystems are developed and manufactured separately and mounted on the satellite structure during the final stages of the assembly process. Such distinct separation of structural-mechanical and non-structural functions increases mass, volume and production expenditure of the entire spacecraft. An approach to eliminate these drawbacks is the concept of a multifunctional structure. Various functions which are normally provided by standalone satellite subsystems and components are integrated into the load-bearing spacecraft structure. The benefits of this technological concept include the reduction of the satellite mass and volume, but also a highly integrative and standardized “one-shot” production process which will make manufacturing, integration, qualification, launch and operation of a satellite more cost and time efficient. For this reason, in the past decades the development of multifunctional structures has increasingly gained interest within the research community.
The project multiSat, promoted by the Federal Ministry of Economic Affairs and Energy, aims at developing
multifunctional load carrying lightweight structures for satellites. In the framework of a comprehensive technological concept several functions are integrated into two typical structural elements of a conventional satellite:a sandwich panel and a tube. As composite materials such as CFRP offer high lightweight potential and their mechanical and physical properties can be tailored to specific mechanical and environmental loads they are increasingly being used in spacecraft structures. Due to their multi-layer character composites are predestined and selected as material for the multifunctional structure because different layers within the composite can be used to provide different and specific functions. Focus is not only laid on the structural-mechanical aspects and the conceptual design, but also on diverse functionality and efficient and standardized manufacturing processes. The integrative concept shall add six functions to the loadcarrying structure. They can be divided into three passive functions, which include heat transfer, radiation shielding and impact protection, and three active functions, namely vibration reduction, energy and data transfer.