{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T13:22:19Z","timestamp":1770988939952,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2018,11,5]],"date-time":"2018-11-05T00:00:00Z","timestamp":1541376000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["CNS-1704899, CNS-1815274, CNS-1149611 and 535 CMMI-1653550"],"award-info":[{"award-number":["CNS-1704899, CNS-1815274, CNS-1149611 and 535 CMMI-1653550"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100006785","name":"Google","doi-asserted-by":"publisher","award":["gift"],"award-info":[{"award-number":["gift"]}],"id":[{"id":"10.13039\/100006785","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100002418","name":"Intel Corporation","doi-asserted-by":"publisher","award":["gift"],"award-info":[{"award-number":["gift"]}],"id":[{"id":"10.13039\/100002418","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Individual perspiration level indicates a person\u2019s physical status as well as their comfort level. Therefore, continuous perspiration level measurement enables people to monitor these conditions for applications including fitness assessment, athlete physical status monitoring, and patient\/elderly care. Prior work on perspiration (sweat) sensing required the user either to be static or to wear the adhesive sensor directly on the skin, which limits users\u2019 mobility and comfort. In this paper, we present a novel conductive thread-based textile sensor that measures an individual\u2019s on-cloth sweat quantity. The sensor consists of three conductive threads. Each conductive thread is surrounded by a braided cotton cover. An additional braided cotton cover is placed outside the three conductive threads, holding them in a position that is stable for measurement. the sensor can be embedded at various locations on a person\u2019s clothing. When the person sweats, the cotton braids absorb the sweat and change the conductivity (resistance) between conductive threads. We used a voltage dividing circuit to measure this resistance as the sensor output (DC). We then conducted a sensor calibration to map this measured voltage to the quantity of electrolyte solution (with the same density as sweat) applied to the sensor. We used this sensor to measure individuals\u2019 perspiration quantity and infer their perceived perspiration levels. The system is able to limit the average prediction error to 0.4 levels when compared to five pre-defined perceived perspiration levels.<\/jats:p>","DOI":"10.3390\/s18113775","type":"journal-article","created":{"date-parts":[[2018,11,5]],"date-time":"2018-11-05T10:43:45Z","timestamp":1541414625000},"page":"3775","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":59,"title":["Conductive Thread-Based Textile Sensor for Continuous Perspiration Level Monitoring"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8684-2908","authenticated-orcid":false,"given":"Ji","family":"Jia","sequence":"first","affiliation":[{"name":"Electrical Engineering Department, Columbia University, New York, NY 10027, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chengtian","family":"Xu","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, Columbia University, New York, NY 10027, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3226-2318","authenticated-orcid":false,"given":"Shijia","family":"Pan","sequence":"additional","affiliation":[{"name":"Electrical and Computer Engineering Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stephen","family":"Xia","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, Columbia University, New York, NY 10027, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter","family":"Wei","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, Columbia University, New York, NY 10027, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hae Young","family":"Noh","sequence":"additional","affiliation":[{"name":"Civil and Environmental Engineering Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pei","family":"Zhang","sequence":"additional","affiliation":[{"name":"Electrical and Computer Engineering Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6480-0299","authenticated-orcid":false,"given":"Xiaofan","family":"Jiang","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, Columbia University, New York, NY 10027, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,11,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1016\/S0074-7696(08)62445-6","article-title":"Cytology of the secretion in mammalian sweat glands","volume":"Volume 87","author":"Kurosumi","year":"1984","journal-title":"International Review of Cytology"},{"key":"ref_2","unstructured":"Tortora, G.J., and Nielsen, M.T. 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