Novel fully automated 3D coreless filament winding technology

Abstract

Coreless filament winding technologies possess the potential to flexibly produce lightweight rigid frame structures at comparably low costs. The key to versatility, geometrical freedom and cost-effectiveness is the avoidance of core elements. Existing research on the filament winding of rigid frames focusses primarily on “isotruss” or “lattice” structures, manufactured by depositing fibers on polygon-shaped mandrels with carved-out gaps. Therefore, an investigation into the performance of coreless wound laminates and their material characteristics under process conditions is performed. Therefore, generic 2D specimens were manufactured on a new fully automated 3D winding equipment and successively exposed to incineration, micro-CT analysis and tensile testing. The benefits of core elements are evaluated by additional reference samples and opposed to coreless winding methods. The research demonstrates the potential of coreless filament winding and inductively quantifies the positive influence of fiber pretension and core/die elements on the material properties at cost of decreased versatility, costs and design degrees of freedom.

3D truss structures with coreless 3D filament winding technology

“…An approach based on filament winding has evolved, enabling the manufacturing of continuous rigid frame structures. 1,2 This has been facilitated by advancements in the filament winding technique itself, moving away from the classical turning lathe principle toward more complex machinery and depositing technologies. The underlying filament winding strategy of perimetrical fiber deposition by rotating a core element around its axis for the manufacturing of closed shell topologies was extended to cross winding methods for rigid frame topologies.…”

“…Correspondingly, the fibers are wound and deflected inside the tool gaps to form separate fiber strands of a rigid frame structure in contrast to depositing them on top of convex core elements to form shell-like surfaces. 1,2 In this context, two basic tool principles are observable and differentiable: solid and modular cores. This subdivision is successively used to analyze the state of the art of these cross winding methods.…”

“…However, this led to the induction of additional fiber angles, due to filaments forced out of their natural geodesic orientation and thereby resulted in a decreased ultimate tensile strength. 2…”

“…However, in comparison to parallel loop connections, the tensile strength was reduced by more than 50% in each case by the constriction of the fiber strands. 2,10…”

“…The objective of this publication is the advancement of the coreless filament winding technology developed in Minsch et al. 2 toward a generic manufacturing process for three-dimensional truss structures. For this purpose, a flexible tool has to be developed capable of supporting this adaptable equipment technology.…”