Comparison between the Classic Sensor Embedding Method and the Monitoring Patch Embedding Method for Composites Instrumentation

摘要

In this paper, the classic embedding technique, with bared sensors, and a recent proposal, the monitoring patch, are compared with the aim to improve the composites in-core instrumentation. The monitoring patch emerges with the need to industrialize sensors integration inside composite structures; thus, a complete evaluation of its mechanical performance has to be done. Numerical and experimental campaigns are carried out on elementary carbon-epoxy coupons to evaluate the benefits and disadvantages of this procedure compared with the typical interlayer sensor embedding. The results show that the use of monitoring patch does not affect significantly the mechanical performance of instrumented coupons. An instrumentation transfer function (ITF) is proposed to link the information that electronic devices can detect, the mechanical phenomena around these electronic devices and the measurements data acquired by global or local techniques (DIC, FEM, gauges). A good correlation between the strain data acquired and the strain values calculated by FEM confirms the approach of the ITF to evaluate the influence of the monitoring patch on the measured signal.