Utilizing 3D printing for the packaging of fiber optic sensors

Fiber optic sensors have the advantage of e.g. being small in size, resistant to corrosion, electrically passive and easy to multiplex. Consequently, in the past fiber sensors have been used successfully for the structural health monitoring (SHM) of bridges, sewerage tunnels or dams, for instance. However, when applied in SHM the development of an appropriate packaging for the sensors is required in order to reliably monitor the parameters of interest as well as to withstand the harsh conditions of the environment. Since 3D printers allow the fabrication of tailored mechanical structures they also lend themselves for the development of low-cost and customized packaging for optic sensor systems. In this work, the packaging of fiber optic strain sensors is investigated by using a conventional 3D printer Makerbot Replicator 2X. A customized packaging with an embedded Fibre Bragg Grating (FBG) was realized and the resulting optical and mechanical properties were characterized. The results verify that depending on the design, filament as well as bonding agent applied a packaging for a fiber optic strain sensor can be developed which meets the requirements for future SHM applications.