2024-03-29T02:32:31Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/709132022-11-17T02:08:08Zhdl_2115_20045hdl_2115_139Damage detection in pipes based on acoustic excitations using laser-induced plasma1000060224416Kajiwara, ItsuroAkita, RyosukeHosoya, Naokiopen accessCreative Commons Attribution-NonCommercial-NoDerivatives 4.0 InternationalLaser-induced plasmaAcoustic excitationHealth monitoringDamage detectionWavelet transform547A health-monitoring system is proposed to detect holes drilled in a pipe based on laser plasma acoustic excitations and acoustic measurements. In this system, an acoustic excitation is applied to a pipe via a laser-induced plasma in air generated by a high-power Nd:YAG pulse laser. Laser-induced plasmas can realize non-contact acoustic impulse excitations. A microphone is used to measure the time response of the acoustic pressure. In this study, we focus on the detection of a hole in the pipe. The reflection of the acoustic wave due to a hole drilled in the pipe induces a change in the time response of the acoustic pressure. Applying a continuous wavelet transform to the measured time response data with/ without the hole can locate the position of the hole. This study demonstrates the effectiveness of the present damage detection method based on an acoustic excitation using a laser-induced plasma.Elsevier2018-10engjournal articleVoRhttp://hdl.handle.net/2115/70913https://doi.org/10.1016/j.ymssp.2018.04.0040888-3270Mechanical systems and signal processing111570579https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/70913/1/1-s2.0-S088832701830195X-main.pdfapplication/pdf1.1 MB2018-10