Dynamic strain measurements by fibre Bragg grating sensor

In this work, we describe a fibre Bragg grating (FBG) sensing system for static and dynamic strain measurements. Low cost and simple grating-based demodulation technique has been used to interrogate the strain induced Bragg wavelength shift. Experimental results showing the capability of the proposed system to perform static strain measurements with 1 muepsilon resolution and a linear response are presented. The same system was also used for dynamic strain detection. Here, a fibre grating was bonded to a piezoceramic actuator in different configurations. A laser triangulation-based system has been used as reference measurements up to 10 kHz while dynamic strain measurements by FBG have been carried out up to 50 kHz demonstrating a dynamic resolution of approximate to40 nepsilon/Hz(1/2), leading to the possibility to perform high frequency detection for on-line structural health monitoring in civil, aeronautic, and aerospace applications. (C) 2003 Published by Elsevier B.V.