{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T18:31:08Z","timestamp":1775845868178,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2022,9,4]],"date-time":"2022-09-04T00:00:00Z","timestamp":1662249600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Targeted therapy for sleep apnoea: A novel personalised approach"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Heart rate (HR) and respiratory rate (RR) are two vital parameters of the body medically used for diagnosing short\/long-term illness. Out-of-the-body, non-skin-contact HR\/RR measurement remains a challenge due to imprecise readings. \u201cInvisible\u201d wearables integrated into day-to-day garments have the potential to produce precise readings with a comfortable user experience. Sleep studies and patient monitoring benefit from \u201cInvisibles\u201d due to longer wearability without significant discomfort. This paper suggests a novel method to reduce the footprint of sleep monitoring devices. We use a single silver-coated nylon fabric band integrated into a substrate of a standard cotton\/nylon garment as a resistive elastomer sensor to measure air and blood volume change across the chest. We introduce a novel event-based architecture to process data at the edge device and describe two algorithms to calculate real-time HR\/RR on ARM Cortex-M3 and Cortex-M4F microcontrollers. RR estimations show a sensitivity of 99.03% and a precision of 99.03% for identifying individual respiratory peaks. The two algorithms used for HR calculation show a mean absolute error of 0.81 \u00b1 0.97 and 0.86\u00b10.61 beats\/min compared with a gold standard ECG-based HR. The event-based algorithm converts the respiratory\/pulse waveform into instantaneous events, therefore reducing the data size by 40\u2013140 times and requiring 33% less power to process and transfer data. Furthermore, we show that events hold enough information to reconstruct the original waveform, retaining pulse and respiratory activity. We suggest fabric sensors and event-based algorithms would drastically reduce the device footprint and increase the performance for HR\/RR estimations during sleep studies, providing a better user experience.<\/jats:p>","DOI":"10.3390\/s22176689","type":"journal-article","created":{"date-parts":[[2022,9,8]],"date-time":"2022-09-08T04:18:32Z","timestamp":1662610712000},"page":"6689","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Electrodeless Heart and Respiratory Rate Estimation during Sleep Using a Single Fabric Band and Event-Based Edge Processing"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1849-4235","authenticated-orcid":false,"given":"Titus","family":"Jayarathna","sequence":"first","affiliation":[{"name":"The MARCS Institute, Western Sydney University, Westmead, NSW 2145, Australia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2616-2804","authenticated-orcid":false,"given":"Gaetano D.","family":"Gargiulo","sequence":"additional","affiliation":[{"name":"The MARCS Institute, Western Sydney University, Westmead, NSW 2145, Australia"},{"name":"School of Engineering, Design and Built Environment, Western Sydney University, Penrith, NSW 2750, Australia"},{"name":"Ingham Institute of Applied Medical Research, Liverpool, NSW 2052, Australia"},{"name":"Translational Health Research Institute, Westmead, NSW 2145, Australia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1042-5793","authenticated-orcid":false,"given":"Gough Y.","family":"Lui","sequence":"additional","affiliation":[{"name":"The MARCS Institute, Western Sydney University, Westmead, NSW 2145, Australia"}]},{"given":"Paul P.","family":"Breen","sequence":"additional","affiliation":[{"name":"The MARCS Institute, Western Sydney University, Westmead, NSW 2145, Australia"},{"name":"Ingham Institute of Applied Medical Research, Liverpool, NSW 2052, Australia"},{"name":"Translational Health Research Institute, Westmead, NSW 2145, Australia"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1016\/j.smrv.2011.02.005","article-title":"Heart rate variability, sleep and sleep disorders","volume":"16","author":"Stein","year":"2012","journal-title":"Sleep Med. 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