{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T01:15:06Z","timestamp":1782782106655,"version":"3.54.5"},"reference-count":34,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,3,21]],"date-time":"2024-03-21T00:00:00Z","timestamp":1710979200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2013Next Generation EU\u2013NRRP M4.C2\u2013Investment 1.5 Establishing and Strengthening of Innovation Ecosystems for Sustainability (Rome Technopole)","award":["ECS00000024"],"award-info":[{"award-number":["ECS00000024"]}]},{"name":"European Union\u2013Next Generation EU\u2013NRRP M4.C2\u2013Investment 1.5 Establishing and Strengthening of Innovation Ecosystems for Sustainability (Rome Technopole)","award":["101128983"],"award-info":[{"award-number":["101128983"]}]},{"name":"European project PROVIDE (\u201cPrediction and prevention of cardiovascular diseases in pre- and type 2 diabetes\u201d)","award":["ECS00000024"],"award-info":[{"award-number":["ECS00000024"]}]},{"name":"European project PROVIDE (\u201cPrediction and prevention of cardiovascular diseases in pre- and type 2 diabetes\u201d)","award":["101128983"],"award-info":[{"award-number":["101128983"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Respiratory rate (fR) monitoring through wearable devices is crucial in several scenarios, providing insights into well-being and sports performance while minimizing interference with daily activities. Strain sensors embedded into garments stand out but require thorough investigation for optimal deployment. Optimal sensor positioning is often overlooked, and when addressed, the quality of the respiratory signal is neglected. Additionally, sensor metrological characterization after sensor integration is often omitted. In this study, we present the design, development, and feasibility assessment of a smart t-shirt embedded with two flexible sensors for fR monitoring. Guided by a motion capture system, optimal sensor design and position on the chest wall were defined, considering both signal magnitude and quality. The sensors were developed, embedded into the wearable system, and metrologically characterized, demonstrating a remarkable response to both static (sensitivity 9.4\u00a0\u03a9\u22c5%\u22121 and 9.1\u00a0\u03a9\u22c5%\u22121\u00a0for sensor A and sensor B, respectively) and cyclic loads (min. hysteresis span 20.4% at 36 bpm obtained for sensor A). The feasibility of the wearable system was assessed on healthy volunteers both under static and dynamic conditions (such as running, walking, and climbing stairs). A mean absolute error of 0.32 bpm was obtained by averaging all subjects and tests using the combination of the two sensors. This value was lower than that obtained using both sensor A (0.53 bpm) and sensor B (0.78 bpm) individually. Our study highlights the importance of signal amplitude and quality in optimal sensor placement evaluation, as well as the characterization of the embedded sensors for metrological assessment.<\/jats:p>","DOI":"10.3390\/s24062018","type":"journal-article","created":{"date-parts":[[2024,3,22]],"date-time":"2024-03-22T05:10:53Z","timestamp":1711084253000},"page":"2018","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Flexible Textile Sensors-Based Smart T-Shirt for Respiratory Monitoring: Design, Development, and Preliminary Validation"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3525-0213","authenticated-orcid":false,"given":"Chiara","family":"Romano","sequence":"first","affiliation":[{"name":"Research Unit of Measurements and Biomedical Instrumentation, Departmental of Engineering, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniela","family":"Lo Presti","sequence":"additional","affiliation":[{"name":"Research Unit of Measurements and Biomedical Instrumentation, Departmental of Engineering, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome, Italy"},{"name":"Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5863-8336","authenticated-orcid":false,"given":"Sergio","family":"Silvestri","sequence":"additional","affiliation":[{"name":"Research Unit of Measurements and Biomedical Instrumentation, Departmental of Engineering, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9696-1265","authenticated-orcid":false,"given":"Emiliano","family":"Schena","sequence":"additional","affiliation":[{"name":"Research Unit of Measurements and Biomedical Instrumentation, Departmental of Engineering, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome, Italy"},{"name":"Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3090-5623","authenticated-orcid":false,"given":"Carlo","family":"Massaroni","sequence":"additional","affiliation":[{"name":"Research Unit of Measurements and Biomedical Instrumentation, Departmental of Engineering, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome, Italy"},{"name":"Fondazione Policlinico Universitario Campus Bio-Medico, Via Alvaro del Portillo, 200, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"232","DOI":"10.1055\/s-0038-1633863","article-title":"Wearable Systems for Health Care Applications","volume":"43","author":"Lukowicz","year":"2004","journal-title":"Methods Inf. 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