Evaluation of debonding progress in composite bonded structures by ultrasonic wave sensing with fiber Bragg grating sensors

Yoji Okabe; Junichiro Kuwahara; Nobuo Takeda; Toshimichi Ogisu; Seiji Kojima; Shinji Komatsuzaki

doi:10.1117/12.657510

16 March 2006 Evaluation of debonding progress in composite bonded structures by ultrasonic wave sensing with fiber Bragg grating sensors

Yoji Okabe, Junichiro Kuwahara, Nobuo Takeda, Toshimichi Ogisu, Seiji Kojima, Shinji Komatsuzaki

Author Affiliations +

Proceedings Volume 6179, Advanced Sensor Technologies for Nondestructive Evaluation and Structural Health Monitoring II; 61790G (2006) https://doi.org/10.1117/12.657510
Event: Nondestructive Evaluation for Health Monitoring and Diagnostics, 2006, San Diego, CA, United States

Abstract

The authors are constructing a damage detection system using ultrasonic waves. In this system, a piezo-ceramic actuator generates ultrasonic waves in a carbon fiber reinforced plastic (CFRP) laminate. After the waves propagate in the laminate, transmitted waves are received by a fiber Bragg grating (FBG) sensor using a newly developed high-speed optical wavelength interrogation system. In this research, this system was applied to the evaluation of debonding progress in CFRP bonded structures. At first, small-diameter FBG sensors, whose cladding diameter is about 1/3 of common optical fibers, were embedded in an adhesive layer of a double-lap type coupon specimen consisting of CFRP quasi-isotropic laminates, and the ultrasonic wave was propagated through the debonded region. After that, the wavelet transform was applied to the received waveforms and the results showed clear difference depending on the debonding length. Hence, a new damage index was proposed, which could be obtained from the difference in the distribution of the wavelet transform coefficient. As a result, the damage index increased with an increase in the debonded area. Furthermore this system was applied to the skin/stringer structural element of airplanes made of CFRP laminates. Both of the waves received by a bonded FBG and by an embedded FBG changed sensitively to the debonding progress. Also, the damage index could evaluate the length of the debonding between the skin and the stringer.

Citation Download Citation

Yoji Okabe, Junichiro Kuwahara, Nobuo Takeda, Toshimichi Ogisu, Seiji Kojima, and Shinji Komatsuzaki "Evaluation of debonding progress in composite bonded structures by ultrasonic wave sensing with fiber Bragg grating sensors", Proc. SPIE 6179, Advanced Sensor Technologies for Nondestructive Evaluation and Structural Health Monitoring II, 61790G (16 March 2006); https://doi.org/10.1117/12.657510

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available