Location of Embedded Fiber Optic Sensors for Minimized Impact Vulnerability

Abstract

Vulnerability of embedded fiber optic sensors such as Bragg grating sensors to impact has been studied in composite laminated plates. The effects of the distance from the supporting boundary and the sensor thickness position were determined. The main objective was to develop an accurate numerical procedure to calculate the local stresses at the sensor from impact in order to determine the criticality with respect to damage initiation. A semi-analytical and a finite element based method were used to consider the contact at impact. From the analysis, it was found that a lower impact energy was required to cause damage in the sensor region when the sensor was embedded close to the boundary. At locations far from boundaries, sensors should not be embedded close to the plate surfaces. For sensors embedded close to a boundary, a thickness position close to the upper surface was found to be less suitable than other positions.

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