Nature is the prototype for material-efficient structures. A look at flora and fauna reveals how selective use of materials and optimized topologies create efficient structures such as the honeycomb pattern in beehives or similar, natural lattice structures, which are lightweight and resilient. Many of these findings can also be applied to fiber composite plastics (FRP): Organic materials like carbon fibers can be combined in a plastic matrix and then processed into bionic structures. However, the full potential of fiber composite structures cannot be exploited when conventional production techniques are applied. To further increase resource efficiency, the Fraunhofer IPT and its partners in the "BioStrukt" research project are developing a plant technology based on tape laying for automated production of bionic FRP structures.
The aim of the “BioStrukt” project is to produce bionic organic sheets with Fiber Steering by tape-laying which enable material- and cost-efficient lightweight components through forming and back-injection. For this purpose, a process chain is being set up that combines the production technologies and links them with an innovative handling system and continuous quality monitoring. By taking a holistic view of the process chain, from the production of the bionic organic sheet to the finished technology demonstrator, the project allows a technological and economic consideration of resource efficiency, productivity and process reliability.
The many findings already gained on the curve deposition of tapes from previous projects, such as from “TapeTwist”, are being further developed at the Fraunhofer IPT for an automated application with a higher level of technological maturity (goal: TRL 7). For this purpose, the in-situ tape laying system “PrePro®2D” is being expanded so that thermoplastic UD tapes can be applied in curved tracks with defined radii. The Fraunhofer IPT is investigating the thermoforming of bionic organic sheets in a two-stage back-injection process for further processing of bionic organic sheets. By specific handling of the bionic organic sheets, it is achieved that they retain their shape in the heated state and have the desired fiber orientations after thermoforming. In order to ensure that the process chain is technologically and economically viable and that the quality of the semi-finished product and the final component is evaluated throughout, all data is collected, centrally stored and analyzed in accordance with “Industry 4.0”. In the end, not only an economic storage of bionic organic sheets can be realized, but also a holistic quality assessment.