{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T10:00:27Z","timestamp":1768471227086,"version":"3.49.0"},"reference-count":21,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,5,17]],"date-time":"2021-05-17T00:00:00Z","timestamp":1621209600000},"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>This paper presents the concept, design, construction, and validation of a novel probe based on the hexadic disposition of six pressure sensors suitable for measuring triaxial stress states inside bulky soft materials. The measurement of triaxial stress states inside bulk materials such as brain tissue surrogates is a challenging task needed to investigate internal organs\u2019 stress states and validate FE models. The purpose of the work was the development and validation of a 17 \u00d7 17 \u00d7 17 mm probe containing six pressure sensors. To do so, six piezoresistive pressure sensors of 6 mm diameter were arranged into an hexad at three cartesian axes and bisecting angles, based on the analytical solution of the stress tensor. The resulting probe was embedded in a soft silicone rubber of known characteristics, calibrated under cyclic compression and shear in three orientations, and statically validated with combined loads. A calibration matrix was computed, and validation tests allowed us to estimate Von Mises stress under combined stress with an error below 6%. Hence, the proposed probe design and method can give indications about the complex stress state developing internally to soft materials under triaxial high-strain fields, opening applications in the analysis of biological models or physical surrogates involving parenchyma organs.<\/jats:p>","DOI":"10.3390\/s21103487","type":"journal-article","created":{"date-parts":[[2021,5,17]],"date-time":"2021-05-17T12:19:57Z","timestamp":1621253997000},"page":"3487","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Novel Multi-Axial Pressure Sensor Probe for Measuring Triaxial Stress States Inside Soft Materials"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0837-6489","authenticated-orcid":false,"given":"Giuseppe","family":"Zullo","sequence":"first","affiliation":[{"name":"Department of Industrial Engineering, University of Padua, Via Venezia 1, 35131 Padua, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anna Leidy","family":"Silvestroni","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Padua, Via Venezia 1, 35131 Padua, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gianluca","family":"Candiotto","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Padua, Via Venezia 1, 35131 Padua, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2964-9500","authenticated-orcid":false,"given":"Andrey","family":"Koptyug","sequence":"additional","affiliation":[{"name":"Department of Quality and Mechanical Engineering, Mid Sweden University, Campus \u00d6stersund Kunskapens v\u00e4g 8, SE-831 25 \u00d6stersund, Sweden"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6638-484X","authenticated-orcid":false,"given":"Nicola","family":"Petrone","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Padua, Via Venezia 1, 35131 Padua, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1016\/j.jmbbm.2019.04.005","article-title":"The mechanical behavior of brain surrogates manufactured from silicone elastomers","volume":"95","author":"Zhang","year":"2019","journal-title":"J. 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