{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T16:35:23Z","timestamp":1783701323841,"version":"3.55.0"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,6,7]],"date-time":"2023-06-07T00:00:00Z","timestamp":1686096000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Grant-in-Aid for Scientific Research (B), JSPS KAKENHI","award":["22H03450"],"award-info":[{"award-number":["22H03450"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotics"],"abstract":"<jats:p>In a telerehabilitation environment, it is difficult for a therapist to understand the condition of a patient\u2019s finger joints because of the lack of direct assessment. In particular, not enabling the provision of spasticity evaluation significantly reduces the optimal performance of telerehabilitation. In a previous study, it has been proposed that finger stiffness could be estimated using an analytical model of a whole-finger soft actuator. However, because the whole-finger soft actuators require high air pressure for high bending performance and are costly to customize for each patient, using joint modular soft actuators for telerehabilitation turns to be a necessity, though stiffness estimation with joint modular soft actuators has not been studied yet. Another problem is caused by using a marker-based joint angle measurement, which requires the markers to be attached to the exact positions, and limits its application in telerehabilitation. In this study, we proposed a procedure of finger joint stiffness estimation that combines information acquired from a joint modular soft actuator and a marker-less hand joint position acquisition device. Correction parameters were added to the previous analytical model for -the bending analysis of a joint assisted using a joint modular soft actuator. Moreover, a multi-variate regression model was implemented for correcting joint angles obtained from the hand joint position acquisition device. As a result, a reasonable accuracy of stiffness estimation was achieved for rehabilitation with the joint modular soft actuators, which suggests the possibility of using the proposed method to evaluate the finger spasticity in a telerehabilitation environment. This is a big step forward towards optimal hand telerehabilitation.<\/jats:p>","DOI":"10.3390\/robotics12030083","type":"journal-article","created":{"date-parts":[[2023,6,8]],"date-time":"2023-06-08T02:58:32Z","timestamp":1686193112000},"page":"83","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Finger Joint Stiffness Estimation with Joint Modular Soft Actuators for Hand Telerehabilitation"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-2252-7663","authenticated-orcid":false,"given":"Fuko","family":"Matsunaga","sequence":"first","affiliation":[{"name":"Department of Medical Engineering, Graduate School of Engineering, Chiba University, Chiba 263-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1083-1628","authenticated-orcid":false,"given":"Shota","family":"Kokubu","sequence":"additional","affiliation":[{"name":"Department of Medical Engineering, Graduate School of Engineering, Chiba University, Chiba 263-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pablo Enrique","family":"Tortos Vinocour","sequence":"additional","affiliation":[{"name":"Department of Medical Engineering, Graduate School of Engineering, Chiba University, Chiba 263-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ming-Ta","family":"Ke","sequence":"additional","affiliation":[{"name":"Graduate School of Intelligent Data Science, National Yunlin University of Science and Technology, Yunlin 64002, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ya-Hsin","family":"Hsueh","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, National Yunlin University of Science and Technology, Yunlin 64002, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3775-8205","authenticated-orcid":false,"given":"Shao Ying","family":"Huang","sequence":"additional","affiliation":[{"name":"Engineering Product Development Department, Singapore University of Technology and Design, Singapore 487372, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1917-8979","authenticated-orcid":false,"given":"Jose","family":"Gomez-Tames","sequence":"additional","affiliation":[{"name":"Department of Medical Engineering, Graduate School of Engineering, Chiba University, Chiba 263-8522, Japan"},{"name":"Center for Frontier Medical Engineering, Chiba University, Chiba 263-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenwei","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Medical Engineering, Graduate School of Engineering, Chiba University, Chiba 263-8522, Japan"},{"name":"Center for Frontier Medical Engineering, Chiba University, Chiba 263-8522, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"245","DOI":"10.1016\/S0140-6736(13)61953-4","article-title":"Global and Regional Burden of Stroke during 1990-2010: Findings from the Global Burden of Disease Study 2010","volume":"383","author":"Feigin","year":"2014","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2181","DOI":"10.1161\/01.STR.0000087172.16305.CD","article-title":"Probability of Regaining Dexterity in the Flaccid Upper Limb: Impact of Severity of Paresis and Time since Onset in Acute Stroke","volume":"34","author":"Kwakkel","year":"2003","journal-title":"Stroke"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"603","DOI":"10.3182\/20090909-4-JP-2010.00102","article-title":"Telerehabilitation for Fingers and Wrist Using a Hand Rehabilitation Support System and Robot Hand","volume":"42","author":"Mouri","year":"2009","journal-title":"IFAC Proc. 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