{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T13:13:25Z","timestamp":1769519605163,"version":"3.49.0"},"reference-count":30,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2021,8,12]],"date-time":"2021-08-12T00:00:00Z","timestamp":1628726400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009888","name":"Tuscany Region","doi-asserted-by":"publisher","award":["\u201cWellness@Work\u201d (Bando n.2 RS2017, POR FESR 2014\u20132020 Regione Toscana, D.D. n.7165 del 24\/5\/2017)"],"award-info":[{"award-number":["\u201cWellness@Work\u201d (Bando n.2 RS2017, POR FESR 2014\u20132020 Regione Toscana, D.D. n.7165 del 24\/5\/2017)"]}],"id":[{"id":"10.13039\/501100009888","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100015694","name":"Fondazione Cassa di Risparmio di Firenze","doi-asserted-by":"publisher","award":["\u201cMOVE-SENSE\u201d (2018.0979, 2020-2021)"],"award-info":[{"award-number":["\u201cMOVE-SENSE\u201d (2018.0979, 2020-2021)"]}],"id":[{"id":"10.13039\/501100015694","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Continuous monitoring of flexions of the trunk via wearable sensors could help various types of workers to reduce risks associated with incorrect postures and movements. Stretchable piezo-capacitive elastomeric sensors based on dielectric elastomers have recently been described as a wearable, lightweight and cost-effective technology to monitor human kinematics. Their stretching causes an increase of capacitance, which can be related to angular movements. Here, we describe a wearable wireless system to detect flexions of the trunk, based on such sensors. In particular, we present: (i) a comparison of different calibration strategies for the capacitive sensors, using either an accelerometer or a gyroscope as an inclinometer; (ii) a comparison of the capacitive sensors\u2019 performance with those of the accelerometer and gyroscope; to that aim, the three types of sensors were evaluated relative to stereophotogrammetry. Compared to the gyroscope, the capacitive sensors showed a higher accuracy. Compared to the accelerometer, their performance was lower when used as quasi-static inclinometers but also higher in case of highly dynamic accelerations. This makes the capacitive sensors attractive as a complementary, rather than alternative, technology to inertial sensors.<\/jats:p>","DOI":"10.3390\/s21165453","type":"journal-article","created":{"date-parts":[[2021,8,12]],"date-time":"2021-08-12T22:14:36Z","timestamp":1628806476000},"page":"5453","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Wearable Detection of Trunk Flexions: Capacitive Elastomeric Sensors Compared to Inertial Sensors"],"prefix":"10.3390","volume":"21","author":[{"given":"Gabriele","family":"Frediani","sequence":"first","affiliation":[{"name":"Department of Industrial Engineering, University of Florence, 50121 Florence, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5109-3399","authenticated-orcid":false,"given":"Leonardo","family":"Bocchi","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Florence, 50121 Florence, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9403-7944","authenticated-orcid":false,"given":"Federica","family":"Vannetti","sequence":"additional","affiliation":[{"name":"IRCCS Fondazione don Carlo Gnocchi ONLUS, 50143 Florence, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4331-7764","authenticated-orcid":false,"given":"Giovanni","family":"Zonfrillo","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Florence, 50121 Florence, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8496-5085","authenticated-orcid":false,"given":"Federico","family":"Carpi","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Florence, 50121 Florence, Italy"},{"name":"IRCCS Fondazione don Carlo Gnocchi ONLUS, 50143 Florence, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3087","DOI":"10.1097\/00007632-200012010-00018","article-title":"Flexion and Rotation of the Trunk and Lifting at Work Are Risk Factors for Low Back Pain: Results of a Prospective Cohort Study","volume":"25","author":"Hoogendoorn","year":"2000","journal-title":"Spine"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"384","DOI":"10.1093\/occmed\/kqg072","article-title":"Personal and Occupational Predictors of Sciatica in the GAZEL Cohort","volume":"53","author":"Leclerc","year":"2003","journal-title":"Occup. 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