{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T05:08:31Z","timestamp":1772082511469,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,18]],"date-time":"2023-06-18T00:00:00Z","timestamp":1687046400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Institute of Disability and Rehabilitation Research Rehabilitation Engineering Research Center on Rehabilitation Robotics","award":["90REGE0005"],"award-info":[{"award-number":["90REGE0005"]}]},{"name":"National Institute of Disability and Rehabilitation Research Rehabilitation Engineering Research Center on Rehabilitation Robotics","award":["R44HD086953"],"award-info":[{"award-number":["R44HD086953"]}]},{"name":"National Institute of Disability and Rehabilitation Research Rehabilitation Engineering Research Center on Rehabilitation Robotics","award":["R01HD062744"],"award-info":[{"award-number":["R01HD062744"]}]},{"name":"National Institutes of Health","award":["90REGE0005"],"award-info":[{"award-number":["90REGE0005"]}]},{"name":"National Institutes of Health","award":["R44HD086953"],"award-info":[{"award-number":["R44HD086953"]}]},{"name":"National Institutes of Health","award":["R01HD062744"],"award-info":[{"award-number":["R01HD062744"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The ability to count finger and wrist movements throughout the day with a nonobtrusive, wearable sensor could be useful for hand-related healthcare applications, including rehabilitation after a stroke, carpal tunnel syndrome, or hand surgery. Previous approaches have required the user to wear a ring with an embedded magnet or inertial measurement unit (IMU). Here, we demonstrate that it is possible to identify the occurrence of finger and wrist flexion\/extension movements based on vibrations detected by a wrist-worn IMU. We developed an approach we call \u201cHand Activity Recognition through using a Convolutional neural network with Spectrograms\u201d (HARCS) that trains a CNN based on the velocity\/acceleration spectrograms that finger\/wrist movements create. We validated HARCS with the wrist-worn IMU recordings obtained from twenty stroke survivors during their daily life, where the occurrence of finger\/wrist movements was labeled using a previously validated algorithm called HAND using magnetic sensing. The daily number of finger\/wrist movements identified by HARCS had a strong positive correlation to the daily number identified by HAND (R2 = 0.76, p &lt; 0.001). HARCS was also 75% accurate when we labeled the finger\/wrist movements performed by unimpaired participants using optical motion capture. Overall, the ringless sensing of finger\/wrist movement occurrence is feasible, although real-world applications may require further accuracy improvements.<\/jats:p>","DOI":"10.3390\/s23125690","type":"journal-article","created":{"date-parts":[[2023,6,19]],"date-time":"2023-06-19T02:29:19Z","timestamp":1687141759000},"page":"5690","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Counting Finger and Wrist Movements Using Only a Wrist-Worn, Inertial Measurement Unit: Toward Practical Wearable Sensing for Hand-Related Healthcare Applications"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8041-9220","authenticated-orcid":false,"given":"Shusuke","family":"Okita","sequence":"first","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, University of California Irvine, Irvine, CA 92697, USA"},{"name":"Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA 92697, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roman","family":"Yakunin","sequence":"additional","affiliation":[{"name":"College of Computing, Georgia Institute of Technology, Atlanta, GA 30332, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jathin","family":"Korrapati","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Computer Science, University of California Berkeley, Berkeley, CA 94720, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mina","family":"Ibrahim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, University of California Irvine, Irvine, CA 92697, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Diogo","family":"Schwerz de Lucena","sequence":"additional","affiliation":[{"name":"AE Studio, Venice, CA 90291, USA"},{"name":"CAPES Foundation, Ministry of Education of Brazil, Brasilia 70040-020, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vicky","family":"Chan","sequence":"additional","affiliation":[{"name":"Rehabilitation Services, University of California Irvine, Irvine, CA 92697, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3196-8706","authenticated-orcid":false,"given":"David J.","family":"Reinkensmeyer","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, University of California Irvine, Irvine, CA 92697, USA"},{"name":"Department of Anatomy and Neurobiology, University of California Irvine, Irvine, CA 92697, USA"},{"name":"Department of Biomedical Engineering, University of California Irvine, Irvine, CA 92697, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1177\/1362361311402230","article-title":"Motor Skills of Toddlers with Autism Spectrum Disorders","volume":"17","author":"Lloyd","year":"2013","journal-title":"Autism"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Schwerz de Lucena, D., Rowe, J.B., Okita, S., Chan, V., Cramer, S.C., and Reinkensmeyer, D.J. 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