Patch-type extrinsic Fabry-Perot interferometric fiber optic sensor and real-time structural vibration monitoring method using the same

Abstract

A patch-type extrinsic Fabry-Perot interferometric fiber optic sensor and a real-time structural vibration monitoring method using the same are disclosed. The patch-type extrinsic Fabry-Perot interferometric fiber optic sensor is provided by combining the existing EFPI (Extrinsic Fabry-Perot Interferometer) fiber optic sensor with a direction-detecting sensor which can acquire direction information of a strain of a structure, which can solve a signal distortion problem occurring in the existing EFPI fiber optic sensor through a simple signal process. The patch-type extrinsic Fabry-Perot interferometric fiber optic sensor includes a piezoelectric material which can apply a control force to the existing EFPI fiber optic sensor, and a self-sensing bridge circuit for extracting the direction information when the piezoelectric material is used as an actuator, so that the sensible range of strain can be extended and the piezoelectric material can directly be used as the actuator based on the sensed signal.