Preparation of enabling space technologies and building blocks: Development of grid-stiffened cylinders for space transportation applications

The activity is split into two phases. This preliminary phase, is aimed at ensuring all necessary (long lead) manufacturing items and knowledge are available in time for a follow-on activity (in which actual manufacturing of a number of inter-stages will be performed). The activity is highly time sensitive; for the technology to be viable for use as an inter-stage by an interested end-user an adequately mature inter-stage should be available on time (Q3 2022).

Grid stiffened structures are a type of CFRP structure that is created by arranging multiple ribs in a type of lattice network. Each rib is created from unidirectional pre-preg plies and is joined together in nodes. For this particular application/technology also a skin is foreseen to close the gaps left in the grid structure. This type of configuration allows for structures with a very high specific strength and specific stiffness. The activity seeks to further develop the technology for use in a launcher inter-stage application. The foreseen mass savings are perceived to be of great benefit to this domain. All objectives of the activity have been completed. In particular this means: An inter-stage design has been developed in line with interested end-user needs. Material characterization tests have been performed and their results post-processed. Trial panels have been manufactured. CFRP material and necessary manufacturing equipment (a.o. a mandrel) are available on premises. Further development of grid-stiffened technology for launcher (inter-stage) applications will achieve further launcher mass reductions. The realized reductions can be converted in increased useful launcher performance. A follow-on GSTP activity is planned to bring the technology up to TRL 7. In the follow-on activity a number (3) of inter-stages will be manufactured. The second of these inter-stages will be mechanically qualified, so that the third manufactured inter-stage may be considered as a viable candidate for use as a flight inter-stage by the end-user by Q3 2022.