{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T10:00:03Z","timestamp":1780912803929,"version":"3.54.1"},"reference-count":36,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,10]],"date-time":"2022-01-10T00:00:00Z","timestamp":1641772800000},"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>In modern times, the collaboration between humans and machines increasingly rises, combining their respective benefits. The direct physical support causes interaction forces in human\u2013machine interfaces, whereas their form determines both the effectiveness and comfort of the collaboration. However, their correct detection requires various sensor characteristics and remains challenging. Thus, this paper presents a developed low-cost sensor pad working with a silicone capsule and a piezoresistive pressure sensor. Its measurement accuracy is validated in both an isolated testing environment and a laboratory study with four test subjects (gender-balanced), and an application integrated in interfaces of an active upper-body exoskeleton. In the material-testing machine, it becomes apparent that the sensor pad generally features the capability of reliably determining normal forces on its surface until a certain threshold. This is also proven in the real application, where the measurement data of three sensor pads spatially embedded in the exoskeletal interface are compared to the data of an installed multi-axis load cell and a high-resolution flexible pressure map. Here, the consideration of three sensor pads potentially enables detection of exoskeletal support on the upper arm as well as \u201cpoor\u201d fit conditions such as uneven pressure distributions that recommend immediate system adjustments for ergonomic improvements.<\/jats:p>","DOI":"10.3390\/s22020505","type":"journal-article","created":{"date-parts":[[2022,1,10]],"date-time":"2022-01-10T22:03:13Z","timestamp":1641852193000},"page":"505","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Low-Cost Force Sensors Embedded in Physical Human\u2013Machine Interfaces: Concept, Exemplary Realization on Upper-Body Exoskeleton, and Validation"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4834-4761","authenticated-orcid":false,"given":"Niclas","family":"Hoffmann","sequence":"first","affiliation":[{"name":"Department of Production Technologies, Institute of Mechatronics, University of Innsbruck, 6020 Innsbruck, Austria"},{"name":"Laboratory of Manufacturing Technology, Helmut-Schmidt-University (University of the Federal Armed Forces Hamburg), 22043 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samet","family":"Ersoysal","sequence":"additional","affiliation":[{"name":"Department of Production Technologies, Institute of Mechatronics, University of Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gilbert","family":"Prokop","sequence":"additional","affiliation":[{"name":"Department of Production Technologies, Institute of Mechatronics, University of Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthias","family":"Hoefer","sequence":"additional","affiliation":[{"name":"Department of Production Technologies, Institute of Mechatronics, University of Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1286-4458","authenticated-orcid":false,"given":"Robert","family":"Weidner","sequence":"additional","affiliation":[{"name":"Department of Production Technologies, Institute of Mechatronics, University of Innsbruck, 6020 Innsbruck, Austria"},{"name":"Laboratory of Manufacturing Technology, Helmut-Schmidt-University (University of the Federal Armed Forces Hamburg), 22043 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"675","DOI":"10.1007\/s11740-013-0487-x","article-title":"Human Hybrid Robot: A New Concept for Supporting Manual Assembly Tasks","volume":"7","author":"Weidner","year":"2013","journal-title":"Prod. 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