{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T19:35:42Z","timestamp":1775504142623,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,2,14]],"date-time":"2024-02-14T00:00:00Z","timestamp":1707868800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62277039"],"award-info":[{"award-number":["62277039"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"the National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61877042"],"award-info":[{"award-number":["61877042"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In multi-finger coordinated keystroke actions by professional pianists, movements are precisely regulated by multiple motor neural centers, exhibiting a certain degree of coordination in finger motions. This coordination enhances the flexibility and efficiency of professional pianists\u2019 keystrokes. Research on the coordination of keystrokes in professional pianists is of great significance for guiding the movements of piano beginners and the motion planning of exoskeleton robots, among other fields. Currently, research on the coordination of multi-finger piano keystroke actions is still in its infancy. Scholars primarily focus on phenomenological analysis and theoretical description, which lack accurate and practical modeling methods. Considering that the tendon of the ring finger is closely connected to adjacent fingers, resulting in limited flexibility in its movement, this study concentrates on coordinated keystrokes involving the middle and ring fingers. A motion measurement platform is constructed, and Leap Motion is used to collect data from 12 professional pianists. A universal model applicable to multiple individuals for multi-finger coordination in keystroke actions based on the backpropagation (BP) neural network is proposed, which is optimized using a genetic algorithm (GA) and a sparrow search algorithm (SSA). The angular rotation of the ring finger\u2019s MCP joint is selected as the model output, while the individual difference information and the angular data of the middle finger\u2019s MCP joint serve as inputs. The individual difference information used in this study includes ring finger length, middle finger length, and years of piano training. The results indicate that the proposed SSA-BP neural network-based model demonstrates superior predictive accuracy, with a root mean square error of 4.8328\u00b0. Based on this model, the keystroke motion of the ring finger\u2019s MCP joint can be accurately predicted from the middle finger\u2019s keystroke motion information, offering an evaluative method and scientific guidance for the training of multi-finger coordinated keystrokes in piano learners.<\/jats:p>","DOI":"10.3390\/s24041221","type":"journal-article","created":{"date-parts":[[2024,2,14]],"date-time":"2024-02-14T11:18:46Z","timestamp":1707909526000},"page":"1221","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Model of Multi-Finger Coordination in Keystroke Movement"],"prefix":"10.3390","volume":"24","author":[{"given":"Jialuo","family":"Lin","sequence":"first","affiliation":[{"name":"Key Laboratory of Mechanism Theory and Equipment Design, Ministry of Education, Tianjin University, Tianjin 300350, China"}]},{"given":"Baihui","family":"Ding","sequence":"additional","affiliation":[{"name":"Key Laboratory of Mechanism Theory and Equipment Design, Ministry of Education, Tianjin University, Tianjin 300350, China"}]},{"given":"Zilong","family":"Song","sequence":"additional","affiliation":[{"name":"Key Laboratory of Mechanism Theory and Equipment Design, Ministry of Education, Tianjin University, Tianjin 300350, China"}]},{"given":"Zheng","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Mechanism Theory and Equipment Design, Ministry of Education, Tianjin University, Tianjin 300350, China"}]},{"given":"Shengchao","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Mechanism Theory and Equipment Design, Ministry of Education, Tianjin University, Tianjin 300350, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1929","DOI":"10.2147\/NDT.S84090","article-title":"Piano Training in Youths with Hand Motor Impairments after Damage to the Developing Brain","volume":"11","author":"Lampe","year":"2015","journal-title":"Neuropsychiatr. 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