{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T18:07:35Z","timestamp":1773511655500,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2020,9,7]],"date-time":"2020-09-07T00:00:00Z","timestamp":1599436800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Chest wall motion can provide information on critical vital signs, including respiration and heartbeat. Mathematical modelling of chest wall motion can reduce an extensive requirement of human testing in the development of many biomedical applications. In this paper, we propose a mathematical model that simulates a chest wall motion due to cardiorespiratory activity. Chest wall motion due to respiration is simulated based on the optimal chemical\u2013mechanical respiratory control-based mechanics. The theory of relaxation oscillation system is applied to model the motion due to cardiac activity. The proposed mathematical chest wall model can be utilized in designing and optimizing different design parameters for radar-based non-contact vital sign (NCVS) systems.<\/jats:p>","DOI":"10.3390\/s20185094","type":"journal-article","created":{"date-parts":[[2020,9,7]],"date-time":"2020-09-07T09:29:10Z","timestamp":1599470950000},"page":"5094","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Modelling of Chest Wall Motion for Cardiorespiratory Activity for Radar-Based NCVS Systems"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0315-3710","authenticated-orcid":false,"given":"Anuradha","family":"Singh","sequence":"first","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Auckland University of Technology, Auckland 1010, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2159-865X","authenticated-orcid":false,"given":"Saeed Ur","family":"Rehman","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Auckland University of Technology, Auckland 1010, New Zealand"},{"name":"College of Science and Engineering, Flinders University, Adelaide 5042, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sira","family":"Yongchareon","sequence":"additional","affiliation":[{"name":"Department of Information Technology and Software Engineering, Auckland University of Technology, Auckland 1010, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter Han Joo","family":"Chong","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Auckland University of Technology, Auckland 1010, New Zealand"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"985","DOI":"10.1046\/j.1365-2044.2003.03342.x","article-title":"Cardiac scoring systems\u2014What is their value?","volume":"58","author":"Ridley","year":"2003","journal-title":"Anaesthesia"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Adib, F., Kabelac, Z., Katabi, D., and Miller, R. 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