Fiber optic sensors and their applications on structural health monitoring in South Korea

Abstract

Fiber optic sensors can be used to measure some physical quantities through long optical fibers applied on structures. Three types of fiber optic sensors, fiber Bragg grating sensor, Brillouin OTDR(optical time domain reflectometry) and Raman OTDR(optical time domain reflectometry), are mostly useful to sense structural health status. In my works, multiplexing of FBG sensors, Raman OTDR and fiber optic BOTDA(Brillouin Optical Time Domain Analysis) sensor will be introduced in this presentation. Novel auto correction Raman OTDR can only sense temperature without any influence, such as bending losses. Double pulse technique is introduced to enhance spatial resolution of BOTDA. An error compensation of distributed strain measurement is also developed to get precise strain measurement using the BOTDA sensor. Finally, the applications of fiber optic sensors are shown in several fields including aerospace, civil structures and wind turbine blades in South Korea.