This paper addresses the inversion of applied non-uniform strain fields from measured FBG reflection spectra. With recent advances in instrumentation that can measure such reflected spectra dynamically, these spectra can now be tied to different failure modes in composite structures. This unique capability is particularly useful when the FBG sensors are embedded in composite materials and therefore subjected to highly non-uniform strain fields. The calculation of an arbitrary applied strain field from a measured reflection spectrum remains a significant computational effort, however, due to the need for an optimization algorithm. Therefore this data processing has not been applied to FBG reflected spectra collected from dynamic events, due to the large amount of spectra that must be processed. In this article we present a linearization method to calculate the applied strain field, provided that the measured reflection spectra are collected at a sufficiently high acquisition rate.
doi: 10.12783/SHM2015/216