High-speed interrogation of multiplexed fiber Bragg grating sensors for monitoring dynamic strain responses during a flexible plate impact on a water surface

Kit Pan Wong, Hyun Tae Kim, An Wang, Kenneth Kiger, James H. Duncan, Miao Yu

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

The investigation of fluid-structure interaction during the impact of a flexible plate on a water surface has received much attention. Measurement of highly transient, distributed strain of the plate during the slamming event is of great interest. Multiplexed fiber Bragg grating (FBG) strain sensors provide a promising solution for such measurement since these sensors are inherently waterproof and are immune to electromagnetic interference. However, in order to monitor the highly transient, distributed strain responses (up to 20 kHz), high-speed simultaneous interrogation of multiplexed FBG sensors is required, which is challenging by using commercial optical interrogators. We present a tunable-wavelength-filter-based optical interrogation system for high-speed simultaneous interrogation of multiplexed FBG strain sensors and demonstrate its application for structural monitoring of a flexible plate during the slamming event. The interrogation system employs a piezoelectric-transducer-controlled Fabry-Perot tunable filter. By operating the tunable filter at its resonant frequency and demodulating the sensor signal based on a peak tracing method, we demonstrated an interrogation speed of 100 kHz, an interrogation range of 98 nm, and an interrogation resolution of 5 pm. For proof-of-performance, the interrogation system was used to monitor the vibrational responses of a cantilever plate under impact loading and the measurement of vibration modes up to 6.785 kHz was demonstrated. Finally, the slamming experiments were carried out with six multiplexed FBG strain sensors mounted on a flexible plate. The dynamic strain measurement of the plate during the slamming event was successfully demonstrated by using the high-speed FBG interrogation system.

Original languageEnglish
Article numberabc23a
JournalSmart Materials and Structures
Volume29
Issue number12
DOIs
StatePublished - 1 Dec 2020

Keywords

  • Dynamic strain measurement
  • Fiber Bragg grating
  • Fluid-structure interaction
  • High-speed optical interrogation
  • Structural health monitoring

Fingerprint

Dive into the research topics of 'High-speed interrogation of multiplexed fiber Bragg grating sensors for monitoring dynamic strain responses during a flexible plate impact on a water surface'. Together they form a unique fingerprint.

Cite this