Proceedings Article | 10 April 2014
W. Hufenbach, M. Gude, A. Czulak, Martin Kretschmann
KEYWORDS: Sensors, Composites, Fiber optics sensors, Manufacturing, Sensor networks, Failure analysis, Polymers, Optical testing, Structured optical fibers, System integration
Increasing economic, political and ecological pressure leads to steadily rising percentage of modern processing and
manufacturing processes for fibre reinforced polymers in industrial batch production. Component weights beneath a level
achievable by classic construction materials, which lead to a reduced energy and cost balance during product lifetime,
justify the higher fabrication costs. However, complex quality control and failure prediction slow down the substitution
by composite materials. High-resolution fibre-optic sensors (FOS), due their low diameter, high measuring point density
and simple handling, show a high applicability potential for an automated sensor-integration in manufacturing processes,
and therefore the online monitoring of composite products manufactured in industrial scale. Integrated sensors can be
used to monitor manufacturing processes, part tests as well as the component structure during product life cycle, which
simplifies allows quality control during production and the optimization of single manufacturing processes.[1;2]
Furthermore, detailed failure analyses lead to a enhanced understanding of failure processes appearing in composite
materials. This leads to a lower wastrel number and products of a higher value and longer product life cycle, whereby
costs, material and energy are saved.
This work shows an automation approach for FOS-integration in the braiding process. For that purpose a braiding wheel
has been supplemented with an appliance for automatic sensor application, which has been used to manufacture preforms
of high-pressure composite vessels with FOS-networks integrated between the fibre layers. All following manufacturing
processes (vacuum infiltration, curing) and component tests (quasi-static pressure test, programmed delamination) were
monitored with the help of the integrated sensor networks.
Keywords: SHM, high-pressure composite vessel, braiding, automated sensor integration, pressure test, quality control,
optic-fibre sensors, Rayleigh, Luna Technologies
