Evaluation of embedded optical fiber sensors in composites: EFPI sensor fabrication and quasi‐static evaluation

Abstract This article reports on the fabrication and evaluation of extrinsic Fabry–Perot interferometric (EFPI) sensors when embedded in fiber‐reinforced composites and tested under quasi‐static tensile and compressive mechanical loading. The EFPI strain sensors were embedded in carbon fiber composite test specimens, and their performance was compared against a surface‐mounted extensometer and electrical resistance strain gauges. When the composite was subjected to quasi‐static tensile loading, the sensors failed around a strain level of 0.5%; under compressive loading, the sensors survived until the failure of the composite at 1.1% strain. The EFPI sensors used in this study were fabricated in‐house and the issues relating to fabrication are discussed in the context of their performance when embedded in composites. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers