An Optical Fibre Sensor for Acoustic Wave Mode Decomposition

摘要

This paper reports on the development of an optical fibre sensor comprising an array of uniformly distributedBragg gratings that are configured to allow for the detection and modal decomposition of structural plate waves.Aspects of the design, fabrication and validation of the sensor are discussed. Laser vibrometry (LV) and advancednumerical modeling are used to demonstrate the fidelity of dynamic strain measurements furnished by a fibreBragg grating. The sensor is applied in an experimental study involving a metal plate where it is shown thatmode conversion of Lamb waves caused by a structural inhomogeneity is robustly measured.