{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T10:04:55Z","timestamp":1776938695741,"version":"3.51.4"},"reference-count":14,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,12,17]],"date-time":"2017-12-17T00:00:00Z","timestamp":1513468800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"R&amp;D program of Ministry of Trade, Industry &amp; Energy of S. Korea","award":["N015800182"],"award-info":[{"award-number":["N015800182"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Respiratory activity is an essential vital sign of life that can indicate changes in typical breathing patterns and irregular body functions such as asthma and panic attacks. Many times, there is a need to monitor breathing activity while performing day-to-day functions such as standing, bending, trunk stretching or during yoga exercises. A single IMU (inertial measurement unit) can be used in measuring respiratory motion; however, breathing motion data may be influenced by a body trunk movement that occurs while recording respiratory activity. This research employs a pair of wireless, wearable IMU sensors custom-made by the Department of Electrical Engineering at San Diego State University. After appropriate sensor placement for data collection, this research applies principles of robotics, using the Denavit-Hartenberg convention, to extract relative angular motion between the two sensors. One of the obtained relative joint angles in the \u201cSagittal\u201d plane predominantly yields respiratory activity. An improvised version of the proposed method and wearable, wireless sensors can be suitable to extract respiratory information while performing sports or exercises, as they do not restrict body motion or the choice of location to gather data.<\/jats:p>","DOI":"10.3390\/s17122932","type":"journal-article","created":{"date-parts":[[2017,12,19]],"date-time":"2017-12-19T03:54:32Z","timestamp":1513655672000},"page":"2932","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Extraction and Analysis of Respiratory Motion Using Wearable Inertial Sensor System during Trunk Motion"],"prefix":"10.3390","volume":"17","author":[{"given":"Apoorva","family":"Gaidhani","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kee","family":"Moon","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yusuf","family":"Ozturk","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung","family":"Lee","sequence":"additional","affiliation":[{"name":"Electronics and Telecommunications Research Institute, ICT, 218 Gajeong-ro, Yuseong-gu, Daejeon 34129, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Woosub","family":"Youm","sequence":"additional","affiliation":[{"name":"Electronics and Telecommunications Research Institute, ICT, 218 Gajeong-ro, Yuseong-gu, Daejeon 34129, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,12,17]]},"reference":[{"key":"ref_1","unstructured":"(2017, August 08). 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Available online: http:\/\/planning.cs.uiuc.edu\/node102.html."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/12\/2932\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:54:19Z","timestamp":1760208859000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/12\/2932"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,12,17]]},"references-count":14,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2017,12]]}},"alternative-id":["s17122932"],"URL":"https:\/\/doi.org\/10.3390\/s17122932","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,12,17]]}}}