Embedded Wireless Sensor Systems for Resin Flow Monitoring in Glass and Carbon Fiber Composites

The obtained data can be used for modeling the resin flow inside the composite, which is required for simulation and for speeding up the design of new parts. This paper presents a novel wireless sensor system that can be embedded in both glass and carbon fiber composites allowing for the first time to wirelessly measure pressure and temperature throughout the laminate during infusion, giving an insight into the process behavior. We suggest a system, which uses wireless data transmission that does not hurt the vacuum seal, even for sensors deeply embedded between conductive carbon fibers. The current sensor system gives an accurate pressure reading (mbar resolution) that provides information about the pressure gradient in the whole laminate. For carbon fibers, the sensors are soldered on a self-made, flexible, and 10 μm-thick polyimide cable, which is resistant to high temperatures. This makes the system minimally invasive since only a 2 mm × 2.5 mm system remains inside the laminate.