{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T05:26:14Z","timestamp":1776230774396,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2021,10,23]],"date-time":"2021-10-23T00:00:00Z","timestamp":1634947200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Departments of Transportation of Iowa, Kansas, South Carolina, and North Carolina","award":["Transportation Pooled Fund Study TPF-5(449)"],"award-info":[{"award-number":["Transportation Pooled Fund Study TPF-5(449)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The authors have previously proposed corrugated soft elastomeric capacitors (cSEC) to create ultra compliant scalable strain gauges. The cSEC technology has been successfully demonstrated in engineering and biomechanical applications for in-plane strain measurements. This study extends work on the cSEC to evaluate its performance at measuring angular rotation when installed folded at the junction of two plates. The objective is to characterize the sensor\u2019s electromechanical behavior anticipating applications to the monitoring of welded connections in steel components. To do so, an electromechanical model that maps the cSEC signal to bending strain induced by angular rotation is derived and adjusted using a validated finite element model. Given the difficulty in mapping strain measurements to rotation, an algorithm termed angular rotation index (ARI) is formulated to link measurements to angular rotation directly. Experimental work is conducted on a hollow structural section (HSS) steel specimen equipped with cSECs subjected to compression to generate angular rotations at the corners within the cross-section. Results confirm that the cSEC is capable of tracking angular rotation-induced bending strain linearly, however with accuracy levels significantly lower than found over flat configurations. Nevertheless, measurements were mapped to angular rotations using the ARI, and it was found that the ARI mapped linearly to the angle of rotation, with an accuracy of 0.416\u2218.<\/jats:p>","DOI":"10.3390\/s21217017","type":"journal-article","created":{"date-parts":[[2021,10,24]],"date-time":"2021-10-24T22:07:11Z","timestamp":1635113231000},"page":"7017","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Soft Elastomeric Capacitor for Angular Rotation Sensing in Steel Components"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3057-522X","authenticated-orcid":false,"given":"Han","family":"Liu","sequence":"first","affiliation":[{"name":"Department of Civil, Construction and Environmental Engineering, Iowa State University, Ames, IA 50011, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5666-3215","authenticated-orcid":false,"given":"Simon","family":"Laflamme","sequence":"additional","affiliation":[{"name":"Department of Civil, Construction and Environmental Engineering, Iowa State University, Ames, IA 50011, USA"},{"name":"Department of Electrical and Computer Engineering, Iowa State University, Ames, IA 50011, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3439-7539","authenticated-orcid":false,"given":"Jian","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Civil, Environmental and Architectural Engineering, The University of Kansas, Lawrence, KS 66045, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2713-0011","authenticated-orcid":false,"given":"Caroline","family":"Bennett","sequence":"additional","affiliation":[{"name":"Department of Civil, Environmental and Architectural Engineering, The University of Kansas, Lawrence, KS 66045, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2835-6389","authenticated-orcid":false,"given":"William N.","family":"Collins","sequence":"additional","affiliation":[{"name":"Department of Civil, Environmental and Architectural Engineering, The University of Kansas, Lawrence, KS 66045, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5524-2416","authenticated-orcid":false,"given":"Austin","family":"Downey","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208, USA"},{"name":"Department of Civil and Environmental Engineering, University of South Carolina, Columbia, SC 29208, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paul","family":"Ziehl","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208, USA"},{"name":"Department of Civil and Environmental Engineering, University of South Carolina, Columbia, SC 29208, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5056-1154","authenticated-orcid":false,"given":"Hongki","family":"Jo","sequence":"additional","affiliation":[{"name":"Department of Civil, Architectural Engineering and Mechanics, The University of Arizona, Tucson, AZ 85721, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1678","DOI":"10.1002\/adfm.201504755","article-title":"Stretchable, Skin-Mountable, and Wearable Strain Sensors and Their Potential Applications: A Review","volume":"26","author":"Amjadi","year":"2016","journal-title":"Adv. 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