Author(s)

Tingwei Feng ¹, Shihai Cui ¹

Affiliation(s)

¹ School of Mechanical Engineering, Tianjin University of Science and Technology, Tianjin, China

Corresponding Author

Shihai Cui

ABSTRACT

To address the novel occupant posture safety issues associated with rotating seats in intelligent driving scenarios, rear-impact simulations were conducted using the THUMS AM50 human model under four seat angles (0°, 45°, 90° and 135°). By evaluating neck injury criteria (Nkm and NIC), brain injury criterion (BrIC), cervical spine segmental loads, and brain tissue strain responses, the influence of seat rotation on head–neck injury mechanisms was thoroughly investigated. The results indicate that the segmental Nkm response remains relatively low under the standard 0° upright posture. In contrast, rotated seating postures induce relative motion between the head and neck, leading to generally elevated levels of segmental Nkm, NIC, BrIC, and brain strain compared to the baseline condition. Notably, a prominent local rotational risk appears at the C7–T1 segment in the 135° case. This study reveals the potential head–neck injury risks of rotating seats in rear impacts and provides quantitative data to support safety assessments of intelligent vehicle.

KEYWORDS

Rear Impact, Seat Rotation Angle, Biomechanical Human Body Model, Neck Injury, Head Injury

CITE THIS PAPER

Tingwei Feng, Shihai Cui. Effects of Seat Rotation Angle on Occupant Head–Neck Injury Responses in Rear Impact. Journal of Engineering Mechanics and Machinery (2026). Vol. 11, No. 2, 46-53. DOI: http://dx.doi.org/10.23977/jemm.2026.110205.

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