{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,5]],"date-time":"2026-09-05T15:05:35Z","timestamp":1788620735053,"version":"build-2803163510"},"reference-count":32,"publisher":"SAGE Publications","issue":"4","license":[{"start":{"date-parts":[[2022,8,1]],"date-time":"2022-08-01T00:00:00Z","timestamp":1659312000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Soft Robotics"],"published-print":{"date-parts":[[2022,8,1]]},"abstract":"<jats:p>The compliance and deformability of soft robotics allow human\u2013machine interactions in a safe manner without the need of sophisticated control systems inherent in rigid-body robotic devices. However, these advantages introduce controllability and predictability challenges. In this study, we propose a novel fluidic-driven variable stiffness revolute joint (VSRJ) based on hybrid soft-rigid approach to achieve adjustable compliance while addressing the abovementioned challenges. The VSRJ is composed of a silicone rubber cylinder as a pressure chamber and two identical rigid links. The soft cylinder is positioned in a fully closed compartment created by the assembly of the two rigid links, thus constraining its expansion when pressure is applied. By applying pressure, the stiffness of the joint increases accordingly for the following reasons: (1) increasing the friction force between the cylinder and the compartment walls and (2) creating a locking mechanism through the expansion of the cylinder into space between rigid links in a \u201cbump\u201d formation. Experimental results show that the VSRJ can achieve up to 8-fold rotational stiffness enhancement from 0 to 5 bar input pressure within \u221230\u00b0 to +30\u00b0 rotation angle. The modular design of the rigid link allows the assembly of multiple VSRJs to build a variable stiffness structure in which each VSRJ has an independent stiffness and relative position. The VSRJ was characterized in terms of repeatability, torque, and stiffness. The experimental results were validated by finite element analysis. This approach can provide opportunities for the use of this new variable stiffness concept as an efficient alternative to traditional variable-stiffness linkages.<\/jats:p>","DOI":"10.1089\/soro.2020.0196","type":"journal-article","created":{"date-parts":[[2021,7,28]],"date-time":"2021-07-28T16:14:33Z","timestamp":1627488873000},"page":"723-733","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":14,"title":["A Novel Pressure-Controlled Revolute Joint with Variable Stiffness"],"prefix":"10.1177","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3049-0824","authenticated-orcid":false,"given":"Canberk","family":"Sozer","sequence":"first","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy."},{"name":"Department of Excellence in Robotics &amp; AI, Scuola Superiore Sant'Anna, Pisa, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6318-4033","authenticated-orcid":false,"given":"Linda","family":"Patern\u00f2","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy."},{"name":"Department of Excellence in Robotics &amp; AI, Scuola Superiore Sant'Anna, Pisa, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4865-310X","authenticated-orcid":false,"given":"Giuseppe","family":"Tortora","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy."},{"name":"Department of Excellence in Robotics &amp; AI, Scuola Superiore Sant'Anna, Pisa, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6348-1081","authenticated-orcid":false,"given":"Arianna","family":"Menciassi","sequence":"additional","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy."},{"name":"Department of Excellence in Robotics &amp; AI, Scuola Superiore Sant'Anna, Pisa, Italy."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2022,8,8]]},"reference":[{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1557\/adv.2018.159"},{"key":"e_1_3_4_3_2","first-page":"87","volume-title":"In: Laschi C, Rossiter J, Iida F, Cianchetti M, Margheri L, eds","author":"Culha U","unstructured":"Culha U, , Hughes J, , Rosendo A, et al. Design principles for soft-rigid hybrid manipulators. In: Laschi C, Rossiter J, Iida F, Cianchetti M, Margheri L, eds. Soft Robotics: Trends, Applications and Challenges: Proceedings of the Soft Robotics Week, April 25\u201330, 2016, Livorno, Italy (Biosystems & Biorobotics). 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Pressure-driven manipulator with variable stiffness structure. (2020 IEEE International Conference on Robotics and Automation, ICRA). 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