{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T21:02:17Z","timestamp":1778274137580,"version":"3.51.4"},"reference-count":17,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2017,11,21]],"date-time":"2017-11-21T00:00:00Z","timestamp":1511222400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Samsung Research Funding Center of Samsung Electronics","award":["SRFC-IT1701-03"],"award-info":[{"award-number":["SRFC-IT1701-03"]}]},{"name":"National Research Foundation of Korea (NRF)","award":["NRF-2012R1A6A1029029"],"award-info":[{"award-number":["NRF-2012R1A6A1029029"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A new stiffness measurement method is proposed that utilizes the lateral deformation profile of an object under indentation. The system consists of a force measurement module between a pair of equidistant touch sensing modules. Unique feature of the method is that by adjusting the touch module separation, indenter protrusion, and spring constant of the force sensing module, one can choose a desired sensing range for the force module. This feature helps to enhance the stiffness differentiation between objects of similar hardness and avoids measurement saturation. We devised a portable measurement system based on the method, and tested its performance with several materials including polymer foams and human skin.<\/jats:p>","DOI":"10.3390\/s17112686","type":"journal-article","created":{"date-parts":[[2017,11,21]],"date-time":"2017-11-21T11:23:20Z","timestamp":1511263400000},"page":"2686","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A Portable Stiffness Measurement System"],"prefix":"10.3390","volume":"17","author":[{"given":"Onejae","family":"Sul","sequence":"first","affiliation":[{"name":"Institute of Nano Science and Technology, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2864-4329","authenticated-orcid":false,"given":"Eunsuk","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seung-Beck","family":"Lee","sequence":"additional","affiliation":[{"name":"Institute of Nano Science and Technology, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Korea"},{"name":"Department of Electronic Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1894","DOI":"10.1109\/JSEN.2008.2006472","article-title":"Sensor for stiffness measurements within the adult rat hippocampus","volume":"8","author":"Yang","year":"2008","journal-title":"IEEE Sens. 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