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Development of Ultrasonic Wave Propagation Imaging System
Chen-Ciang Chia,Jung-Ryul Lee,Jong Heon Kim 한국비파괴검사학회 2009 한국비파괴검사학회지 Vol.29 No.4
Laser-based ultrasonic sensing requires the probe with fixed focal length, but this requirement is not essential in laser-based ultrasonic generation. Based on this fact, we designed a pulsed laser-based ultrasonic wave propagation imaging (UWPI) system with a tilting mirror system for rapid scanning of target, and an in-line band-pass filtering capable of ultrasonic mode selection. ID-temporal averaging, 2D-spatial averaging, and 3D-data structure building algorithms were developed for clearer results allowing for higher damage detectability. The imaging results on a flat stainless steel plate were presented in movie and snapshot formats which showed the propagation of ultrasound visible as a concentric wavefield emerging from the location of an ultrasonic sensor. A hole in the plate with a diameter of 1 ㎜ was indicated by the scattering wavefields. The results showed that this robust UWPI system is independent of focal length and reference data requirements.
Development of Ultrasonic Wave Propagation Imaging System
Chia, Chen-Ciang,Lee, Jung-Ryul,Kim, Jong-Heon The Korean Society for Nondestructive Testing 2009 한국비파괴검사학회지 Vol.29 No.4
Laser-based ultrasonic sensing requires the probe with fixed fecal length, but this requirement is not essential in laser-based ultrasonic generation. Based on this fact, we designed a pulsed laser-based ultrasonic wave propagation imaging (UWPI) system with a tilting mirror system for rapid scanning of target, and an in-line band-pass filtering capable of ultrasoaic mode selection. 1D-temporal averaging, 2D-spatial averaging, and 3D-data structure building algorithms were developed far clearer results allowing fur higher damage detectability. The imaging results on a flat stainless steel plate were presented in movie and snapshot formats which showed the propagation of ultrasound visible as a concentric wavefield emerging from the location of an ultrasonic sensor. A hole in the plate with a diameter of 1 mm was indicated by the scattering wavefields. The results showed that this robust UWPI system is independent of focal length and reference data requirements.
Chia, Chen Ciang,Jeong, Hyo‐,Mi,Lee, Jung‐,Ryul,Park, Gyuhae John Wiley Sons, Ltd 2012 Structural control and health monitoring Vol.19 No.7
<P><B>SUMMARY</B></P><P>Two aircraft wings made of carbon fiber‐reinforced plastic material were inspected using the laser‐based ultrasonic propagation imaging system for the visualization of manufacturing defect and damages of debonding mode. Hypotheses of the detection mechanism of composite debonding were presented and validated through the inspection results for the bonding lines of the composite wing structures. The inspection showed that the location, shape, and size of the poor bonding defect, artificial stringer tip debonding, and real skin–spar debonding can be visualized and/or measured from the imaging results. The performance of the imaging system was found better than that of a manual ultrasonic C‐scan in terms of spatial resolution and damage detectability. Another finding from the inspection was the occurrence of skin buckling between two riveted locations. Most importantly, the presence of structural elements or features such as spars, stringers, ribs, lugs, inspection windows, and even embedded PZT elements did not adversely affect the inspection. Copyright © 2012 John Wiley & Sons, Ltd.</P>
Chia, Chen Ciang,Lee, Jung-Ryul,Shin, He-Jin IOP Pub 2009 Measurement Science and Technology Vol.20 No.12
<P>The direct attachment of piezoelectric transducers onto hot targets raises formidable challenges as piezoelectric transducers lose their piezoelectric characteristics at elevated temperatures or debond due to thermal expansion coefficient mismatches. We developed a welded fibre acoustic-wave PZT (FAWPZT) sensor to alleviate these temperature limitations. One end of the FAWPZT sensor, made from a stainless steel fibre, was welded onto a stainless steel target plate and the other end was bonded to a PZT sensor. An ultrasonic wave propagation imaging (UWPI) system consists of a laser mirror scanner and a Q-switched pulsed laser (QPL) acting as a non-contact ultrasonic generator was then used to scan a hot target surface with an artificial 2 mm-sized open crack. The result was presented in the form of an ultrasonic wave propagation movie. The damage was detected as a wavefield scattering from the damaged location and its size was evaluated from the plot of amplitude distribution along the propagating wavefront. Sensor performance was briefly discussed and the results confirmed that a FAWPZT sensor combined with a UWPI system has good potential for implementation in hot target integrated structural health management.</P>
Review of Radio Frequency Identification and Wireless Technology for Structural Health Monitoring
Dipesh Dhital,Chen Ciang Chia,Jung-Ryul Lee,Chan-Yik Park 한국비파괴검사학회 2010 한국비파괴검사학회지 Vol.30 No.3
Radio frequency identification(RFID) combined with wireless technology has good potential for structural health monitoring(SHM). We describe several advantages of RFID and wireless technologies for SHM, and review SHM examples with working principles, design and technical details for damage detection, heat exposure monitoring, force/strain sensing, and corrosion detection in concrete, steel, carbon fiber reinforced polymer(CFRP), and other materials. Various sensors combined with wireless communication are also discussed. These methodologies can be readily developed, implemented, and customized. There are some technical difficulties, but solutions are being addressed. Lastly, a surface acoustic wave-based RFID system is presented, and possible future trends of SHM based on RFID and wireless technology are presented.
Review of Radio Frequency Identification and Wireless Technology for Structural Health Monitoring
Dhital, Dipesh,Chia, Chen Ciang,Lee, Jung-Ryul,Park, Chan-Yik The Korean Society for Nondestructive Testing 2010 한국비파괴검사학회지 Vol.30 No.3
Radio frequency identification(RFID) combined with wireless technology has good potential for structural health monitoring(SHM). We describe several advantages of RFID and wireless technologies for SHM, and review SHM examples with working principles, design and technical details for damage detection, heat exposure monitoring, force/strain sensing, and corrosion detection in concrete, steel, carbon fiber reinforced polymer(CFRP), and other materials. Various sensors combined with wireless communication are also discussed. These methodologies can be readily developed, implemented, and customized. There are some technical difficulties, but solutions are being addressed. Lastly, a surface acoustic wave-based RFID system is presented, and possible future trends of SHM based on RFID and wireless technology are presented.