{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,25]],"date-time":"2026-02-25T20:29:41Z","timestamp":1772051381251,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,2,26]],"date-time":"2020-02-26T00:00:00Z","timestamp":1582675200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003052","name":"Ministry of Trade, Industry and Energy","doi-asserted-by":"publisher","award":["20006386"],"award-info":[{"award-number":["20006386"]}],"id":[{"id":"10.13039\/501100003052","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2018R1D1A1B07048575"],"award-info":[{"award-number":["2018R1D1A1B07048575"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Fall-related injury is a common cause of mortality among the elderly. Hip fractures are especially dangerous and can even be fatal. In this study, a threshold-based preimpact fall detection algorithm was developed for wearable airbags that minimize the impact of falls on the user\u2019s body. Acceleration sum vector magnitude (SVM), angular velocity SVM, and vertical angle, calculated using inertial data captured from an inertial measurement unit were used to develop the algorithm. To calculate the vertical angle accurately, a complementary filter with a proportional integral controller was used to minimize integration errors and the effect of external impacts. In total, 30 healthy young men were recruited to simulate 6 types of falls and 14 activities of daily life. The developed algorithm achieved 100% sensitivity, 97.54% specificity, 98.33% accuracy, and an average lead time (i.e., the time between the fall detection and the collision) of 280.25 \u00b1 10.29 ms with our experimental data, whereas it achieved 96.1% sensitivity, 90.5% specificity, and 92.4% accuracy with the SisFall public dataset. This paper demonstrates that the algorithm achieved a high accuracy using our experimental data, which included some highly dynamic motions that had not been tested previously.<\/jats:p>","DOI":"10.3390\/s20051277","type":"journal-article","created":{"date-parts":[[2020,2,27]],"date-time":"2020-02-27T03:21:16Z","timestamp":1582773676000},"page":"1277","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Enhanced Algorithm for the Detection of Preimpact Fall for Wearable Airbags"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9313-7270","authenticated-orcid":false,"given":"Haneul","family":"Jung","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering and Institute of Medical Engineering, Yonsei University, Seoul 03722, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4681-6318","authenticated-orcid":false,"given":"Bummo","family":"Koo","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering and Institute of Medical Engineering, Yonsei University, Seoul 03722, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2053-8994","authenticated-orcid":false,"given":"Jongman","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering and Institute of Medical Engineering, Yonsei University, Seoul 03722, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6678-8561","authenticated-orcid":false,"given":"Taehee","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering and Institute of Medical Engineering, Yonsei University, Seoul 03722, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4879-8165","authenticated-orcid":false,"given":"Yejin","family":"Nam","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering and Institute of Medical Engineering, Yonsei University, Seoul 03722, Korea"}]},{"given":"Youngho","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering and Institute of Medical Engineering, Yonsei University, Seoul 03722, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,26]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (WHO) (2019, December 30). 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