{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:42:06Z","timestamp":1760240526711,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2019,7,1]],"date-time":"2019-07-01T00:00:00Z","timestamp":1561939200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61805075, 61475044"],"award-info":[{"award-number":["61805075, 61475044"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"International Science &amp; Technology Cooperation Program of China","award":["2016YFE0124300"],"award-info":[{"award-number":["2016YFE0124300"]}]},{"name":"Doctoral Scientific Research Foundation of Hubei University of Technology","award":["BSQD2016047"],"award-info":[{"award-number":["BSQD2016047"]}]},{"name":"Open Foundation of Hubei Collaborative Innovation Center for High-efficiency Utilization of Solar Energy","award":["HBSKFZD2017003"],"award-info":[{"award-number":["HBSKFZD2017003"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A novel multipoint fiber loop ringdown (FLRD) strain sensing system using frequency-shifted interferometry (FSI) is proposed and experimentally validated. Compared to conventional multipoint FLRD techniques, this scheme measures the decay rate of the continuous wave (CW) light in the space domain and thus greatly reduces the cost without the requirement of expensive devices. A serial dual-point strain sensing system was experimentally constructed and a biconical tapered multimode fiber (MMF) as the sensor head was used for obtaining the large measuring range. By applying different strains on the sensor heads through translation stages, a linear response between strain and additional loss induced by strain sensor was obtained, and the static strain sensitivities of 0.13676 dB\/m\u03b5 and 0.19665 dB\/m\u03b5 were achieved, corresponding to the detection limit of 0.0123 dB and 0.0360 dB, respectively. Moreover, a large measuring range of approximately 6 m\u03b5 was achieved for both strain sensors. The experimental results indicate that our proposed method offers a promising multipoint strain sensor which has the advantages of low cost, a simple sensing structure and a large measuring range.<\/jats:p>","DOI":"10.3390\/s19132907","type":"journal-article","created":{"date-parts":[[2019,7,1]],"date-time":"2019-07-01T03:23:59Z","timestamp":1561951439000},"page":"2907","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Multipoint Fiber Loop Ringdown Sensors for Large Strain Measurement Using Frequency-Shifted Interferometry"],"prefix":"10.3390","volume":"19","author":[{"given":"Chunfu","family":"Cheng","sequence":"first","affiliation":[{"name":"Hubei Collaborative Innovation Center for High-Efficiency Utilization of Solar Energy, Hubei University of Technology, Wuhan 430068, China"},{"name":"School of Science, Hubei University of Technology, Wuhan 430068, China"}]},{"given":"Zehao","family":"Chen","sequence":"additional","affiliation":[{"name":"Hubei Collaborative Innovation Center for High-Efficiency Utilization of Solar Energy, Hubei University of Technology, Wuhan 430068, China"},{"name":"School of Science, Hubei University of Technology, Wuhan 430068, China"}]},{"given":"Yiwen","family":"Ou","sequence":"additional","affiliation":[{"name":"Hubei Collaborative Innovation Center for High-Efficiency Utilization of Solar Energy, Hubei University of Technology, Wuhan 430068, China"},{"name":"School of Science, Hubei University of Technology, Wuhan 430068, China"}]},{"given":"Jiaxuan","family":"Chen","sequence":"additional","affiliation":[{"name":"Hubei Collaborative Innovation Center for High-Efficiency Utilization of Solar Energy, Hubei University of Technology, Wuhan 430068, China"},{"name":"School of Science, Hubei University of Technology, Wuhan 430068, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,7,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"341","DOI":"10.1002\/stc.377","article-title":"Modal macro-strain flexibility methods for damage localization in flexural structures using long-gage FBG sensors","volume":"18","author":"Adewuyi","year":"2011","journal-title":"Struct. 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