{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T08:44:15Z","timestamp":1768466655280,"version":"3.49.0"},"reference-count":54,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,17]],"date-time":"2021-02-17T00:00:00Z","timestamp":1613520000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Health and Welfare (MOHW, Korea) and Korea Health Industry Development Institute (KHIDI, Korea)","award":["HI19C0462"],"award-info":[{"award-number":["HI19C0462"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Recording human gestures from a wearable sensor produces valuable information to implement control gestures or in healthcare services. The wearable sensor is required to be small and easily worn. Advances in miniaturized sensor and materials research produces patchable inertial measurement units (IMUs). In this paper, a hand gesture recognition system using a single patchable six-axis IMU attached at the wrist via recurrent neural networks (RNN) is presented. The IMU comprises IC-based electronic components on a stretchable, adhesive substrate with serpentine-structured interconnections. The proposed patchable IMU with soft form-factors can be worn in close contact with the human body, comfortably adapting to skin deformations. Thus, signal distortion (i.e., motion artifacts) produced for vibration during the motion is minimized. Also, our patchable IMU has a wireless communication (i.e., Bluetooth) module to continuously send the sensed signals to any processing device. Our hand gesture recognition system was evaluated, attaching the proposed patchable six-axis IMU on the right wrist of five people to recognize three hand gestures using two models based on recurrent neural nets. The RNN-based models are trained and validated using a public database. The preliminary results show that our proposed patchable IMU have potential to continuously monitor people\u2019s motions in remote settings for applications in mobile health, human\u2013computer interaction, and control gestures recognition.<\/jats:p>","DOI":"10.3390\/s21041404","type":"journal-article","created":{"date-parts":[[2021,2,17]],"date-time":"2021-02-17T21:35:42Z","timestamp":1613597742000},"page":"1404","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Hand Gesture Recognition Using Single Patchable Six-Axis Inertial Measurement Unit via Recurrent Neural Networks"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0077-8528","authenticated-orcid":false,"given":"Edwin","family":"Valarezo A\u00f1azco","sequence":"first","affiliation":[{"name":"Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea"},{"name":"Faculty of Engineering in Electricity and Computation, FIEC, Escuela Superior Polit\u00e9cnica del Litoral, ESPOL, Guayaquil EC090112, Ecuador"}]},{"given":"Seung Ju","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea"}]},{"given":"Kangil","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea"}]},{"given":"Patricio Rivera","family":"Lopez","sequence":"additional","affiliation":[{"name":"Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea"}]},{"given":"Tae-Seong","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4396-6118","authenticated-orcid":false,"given":"Sangmin","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"838","DOI":"10.1126\/science.1206157","article-title":"Epidermal electronics","volume":"333","author":"Kim","year":"2011","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1007\/s13534-018-00093-6","article-title":"Wearable EEG and Beyond","volume":"9","author":"Casson","year":"2019","journal-title":"Biomed. 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