{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T01:58:53Z","timestamp":1777514333866,"version":"3.51.4"},"reference-count":35,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2019,2,13]],"date-time":"2019-02-13T00:00:00Z","timestamp":1550016000000},"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 this study, pre-impact fall detection algorithms were developed based on data gathered by a custom-made inertial measurement unit (IMU). Four types of simulated falls were performed by 40 healthy subjects (age: 23.4 \u00b1 4.4 years). The IMU recorded acceleration and angular velocity during all activities. Acceleration, angular velocity, and trunk inclination thresholds were set to 0.9 g, 47.3\u00b0\/s, and 24.7\u00b0, respectively, for a pre-impact fall detection algorithm using vertical angles (VA algorithm); and 0.9 g, 47.3\u00b0\/s, and 0.19, respectively, for an algorithm using the triangle feature (TF algorithm). The algorithms were validated by the results of a blind test using four types of simulated falls and six types of activities of daily living (ADL). VA and TF algorithms resulted in lead times of 401 \u00b1 46.9 ms and 427 \u00b1 45.9 ms, respectively. Both algorithms were able to detect falls with 100% accuracy. The performance of the algorithms was evaluated using a public dataset. Both algorithms detected every fall in the SisFall dataset with 100% sensitivity). The VA algorithm had a specificity of 78.3%, and TF algorithm had a specificity of 83.9%. The algorithms had higher specificity when interpreting data from elderly subjects. This study showed that algorithms using angles could more accurately detect falls. Public datasets are needed to improve the accuracy of the algorithms.<\/jats:p>","DOI":"10.3390\/s19040774","type":"journal-article","created":{"date-parts":[[2019,2,14]],"date-time":"2019-02-14T03:21:46Z","timestamp":1550114506000},"page":"774","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":44,"title":["Evaluation of Inertial Sensor-Based Pre-Impact Fall Detection Algorithms Using Public Dataset"],"prefix":"10.3390","volume":"19","author":[{"given":"Soonjae","family":"Ahn","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, Yonsei University, Wonju 26493, Korea"}]},{"given":"Jongman","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Yonsei University, Wonju 26493, Korea"}]},{"given":"Bummo","family":"Koo","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Yonsei University, Wonju 26493, Korea"}]},{"given":"Youngho","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Yonsei University, Wonju 26493, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"272","DOI":"10.1093\/ageing\/31.4.272","article-title":"Impact of a dedicated syncope and falls facility for older adults on emergency beds","volume":"31","author":"Kenny","year":"2002","journal-title":"Age Ageing"},{"key":"ref_2","first-page":"1","article-title":"The prevention of falls in later life. 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