{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T14:08:15Z","timestamp":1787753295245,"version":"build-2784847793"},"reference-count":24,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,3,27]],"date-time":"2025-03-27T00:00:00Z","timestamp":1743033600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Bioeng. Biotechnol."],"abstract":"<jats:p>In autonomous vehicles, reclined seating positions are increasingly popular for improving occupant comfort, but they also pose significant challenges for crash safety, especially concerning lumbar injury risks. This study investigated the potential of assisted repositioning to mitigate lumbar injuries in reclined occupants during frontal collisions. Assisted repositioning combined active intervention with collision inertia to return reclined occupants to an upright posture prior to peak lumbar loads. THUMS simulations at crash severities from 30\u00a0km\/h to 70\u00a0km\/h demonstrated that assisted repositioning could significantly reduce lumbar injury risk, particularly at 50\u00a0km\/h, where the risk decreased from 66.9% to 32.4%. To provide whole-body protection, this study introduced two solutions for coordinating repositioning devices with the conventional three-point seatbelt. The \u201cactive solution\u201d utilized an active lumbar support for repositioning, while the \u201cpassive solution\u201d employed a lumbar airbag. Both solutions emphasized the need for careful coordination of occupant repositioning with seatbelt functions to optimize safety across different body regions. These findings presented a new strategy for enhancing crash protection in flexible cabin configurations, contributing to occupant safety in future autonomous vehicles.<\/jats:p>","DOI":"10.3389\/fbioe.2025.1540569","type":"journal-article","created":{"date-parts":[[2025,3,28]],"date-time":"2025-03-28T01:15:07Z","timestamp":1743124507000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":6,"title":["Mitigate lumbar crash injury of reclined occupants with assisted repositioning device"],"prefix":"10.3389","volume":"13","author":[{"given":"Wenxuan","family":"Shen","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qing","family":"Zhou","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,3,27]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.4271\/2022-22-0001","article-title":"Investigation of potential injury patterns and occupant kinematics in frontal impact with PMHS in reclined postures","volume":"66","author":"Baudrit","year":"2022","journal-title":"Stapp Car Crash J."},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jbiomech.2022.111051","article-title":"The vision of a comprehensive safety concept","author":"Baumann","year":"2001","journal-title":"SAE"},{"key":"B3","article-title":"A human modelling study on occupant kinematics in highly reclined seats during frontal crashes","volume-title":"Proceedings of IRCOBI","author":"Boyle","year":"2019"},{"key":"B4","doi-asserted-by":"publisher","first-page":"614","DOI":"10.1097\/ta.0b013e318164d071","article-title":"The effect of reclined seats on mortality in motor vehicle collisions","volume":"64","author":"Dissanaike","year":"2008","journal-title":"J. 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