{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T12:53:48Z","timestamp":1787316828756,"version":"build-2736575974"},"reference-count":31,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2024,12,28]],"date-time":"2024-12-28T00:00:00Z","timestamp":1735344000000},"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 the context of neurodegenerative diseases, finger tapping is a gold-standard test used by clinicians to evaluate the severity of the condition. The finger tapping test involves repetitive tapping between the index finger and thumb. Subjects affected by neurodegenerative diseases, such as Parkinson\u2019s disease, often exhibit symptoms like bradykinesia, rigidity, and tremor. As a result, when these individuals perform the finger tapping task, instability in both the tap rate and finger displacement can be observed. Currently, clinicians assess bradykinesia by visually observing the patient\u2019s finger tapping movements and qualitatively rating their severity. In this work, we present a novel ultrasound contactless system that provides quantitative measurements of finger tapping, including tap rate and finger displacements. The system functions as an ultrasound sonar capable of measuring the Doppler spectrum of waves reflected by the hand. From this spectrum, various characteristics of the hand movement can be extracted through appropriate processing techniques. Specifically, by performing time\u2013frequency analysis and applying specialized data processing, tapping rates and finger displacements can be estimated. The system has been tested in real-world scenarios involving volunteer finger tapping sessions, demonstrating its potential for accurately measuring both tap rates and displacements.<\/jats:p>","DOI":"10.3390\/s25010123","type":"journal-article","created":{"date-parts":[[2024,12,31]],"date-time":"2024-12-31T07:00:37Z","timestamp":1735628437000},"page":"123","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["An Ultrasound Prototype for Remote Hand Movement Sensing: The Finger Tapping Case"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7608-6686","authenticated-orcid":false,"given":"Stefano","family":"Franceschini","sequence":"first","affiliation":[{"name":"Department of Engineering, University of Napoli Parthenope, Centro Direzionale, 80143 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9033-8838","authenticated-orcid":false,"given":"Maria Maddalena","family":"Autorino","sequence":"additional","affiliation":[{"name":"Department of Engineering, University of Napoli Parthenope, Centro Direzionale, 80143 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3669-8183","authenticated-orcid":false,"given":"Michele","family":"Ambrosanio","sequence":"additional","affiliation":[{"name":"Department of Economics, Law, Cybersecurity, and Sports Sciences, University of Napoli Parthenope, Via della Repubblica 32, 80035 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5403-5482","authenticated-orcid":false,"given":"Vito","family":"Pascazio","sequence":"additional","affiliation":[{"name":"Department of Engineering, University of Napoli Parthenope, Centro Direzionale, 80143 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5964-8667","authenticated-orcid":false,"given":"Fabio","family":"Baselice","sequence":"additional","affiliation":[{"name":"Department of Engineering, University of Napoli Parthenope, Centro Direzionale, 80143 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Sacrey, L., Germani, T., Bryson, S., and Zwaigenbaum, L. 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