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and Middle-aged College and University Backbone Teachers Cultivation Program and Innovation Project of Guangxi Graduate Education","award":["AB18221033"],"award-info":[{"award-number":["AB18221033"]}]},{"name":"Guangxi One Thousand Young and Middle-aged College and University Backbone Teachers Cultivation Program and Innovation Project of Guangxi Graduate Education","award":["AB21075009"],"award-info":[{"award-number":["AB21075009"]}]},{"name":"Guangxi One Thousand Young and Middle-aged College and University Backbone Teachers Cultivation Program and Innovation Project of Guangxi Graduate Education","award":["YCSW2020098"],"award-info":[{"award-number":["YCSW2020098"]}]},{"name":"Guangxi One Thousand Young and Middle-aged College and University Backbone Teachers Cultivation Program and Innovation Project of Guangxi Graduate Education","award":["20210217-3"],"award-info":[{"award-number":["20210217-3"]}]},{"name":"Science research and Technology Development project of Guilin city","award":["62165002"],"award-info":[{"award-number":["62165002"]}]},{"name":"Science research and Technology Development project of Guilin city","award":["AB18221033"],"award-info":[{"award-number":["AB18221033"]}]},{"name":"Science research and Technology Development project of Guilin city","award":["AB21075009"],"award-info":[{"award-number":["AB21075009"]}]},{"name":"Science research and Technology Development project of Guilin city","award":["YCSW2020098"],"award-info":[{"award-number":["YCSW2020098"]}]},{"name":"Science research and Technology Development project of Guilin city","award":["20210217-3"],"award-info":[{"award-number":["20210217-3"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A fiber-optic torsion sensor based on a helical two-core fiber (HTCF) is proposed and experimentally demonstrated for simultaneously measuring torsion angle and torsion direction. The sensor consists of a segment of HTCF and two single-mode fibers (SMFs) forming a Mach\u2013Zehnder interferometer (MZI). The helical structure is implemented by pre-twisting a 1 cm long two-core fiber (TCF). The performance of the sensor with pre-twisted angles of 180\u00b0, 360\u00b0, and 540\u00b0 is experimentally analyzed. The results show that the sensor can realize the angular measurement and effectively distinguish the torsion direction. It is worth noting that the sensor has maximum sensitivity when the pre-twist angle is 180 degrees. The obtained wavelength sensitivities of torsion and temperature are 0.242 nm\/(rad\/m) and 32 pm\/\u00b0C, respectively. The sensor has the advantages of easy fabrication, low cost, compact structure, and high sensitivity, which is expected to yield potential applications in fields where both torsion angle and direction measurements are required.<\/jats:p>","DOI":"10.3390\/s23062874","type":"journal-article","created":{"date-parts":[[2023,3,7]],"date-time":"2023-03-07T01:43:35Z","timestamp":1678153415000},"page":"2874","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Directional Torsion Sensor Based on a Two-Core Fiber with a Helical Structure"],"prefix":"10.3390","volume":"23","author":[{"given":"Zhuo","family":"Song","sequence":"first","affiliation":[{"name":"Guangxi Key Laboratory of Nuclear Physics and Technology, College of Physics Science and Technology, Guangxi Normal University, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yichun","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Joint International Research Laboratory of Specialty Fiber Optics and Advanced Communication, Shanghai Institute for Advanced Communication and Data Science, Shanghai University, Shanghai 200444, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0472-6178","authenticated-orcid":false,"given":"Junhui","family":"Hu","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Nuclear Physics and Technology, College of Physics Science and Technology, Guangxi Normal University, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"100190","DOI":"10.1016\/j.rineng.2020.100190","article-title":"Prediction of the business jet Global 7500 wing deformed shape using fiber Bragg gratings and neural network","volume":"9","author":"Klotz","year":"2021","journal-title":"Results Eng."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1007\/s13320-012-0065-4","article-title":"Use of FBG sensors for SHM in aerospace structures","volume":"2","author":"Kahandawa","year":"2012","journal-title":"Photonic Sens."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2509","DOI":"10.1038\/s41467-018-04860-y","article-title":"Dynamic strain determination using fibre-optic cables allows imaging of seismological and structural features","volume":"9","author":"Jousset","year":"2018","journal-title":"Nat. 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