THUMS 假人在防冲击姿势下头颈部损伤分析

Head and neck injury analysis of THUMS HBM in brace position

摘要:

在应急着陆过程中，乘员采用不同种防冲击姿势会产生不同的保护效果。建立基于THUMS 生物力学假人的座椅/乘员约束系统模型，对比在水平16g 冲击下直立式坐姿、头顶且手顶式坐姿和头顶式坐姿下的头颈部损伤情况，并提出双手抱颈式防冲击姿势；分析颈部轴向拉力、压力、前向弯矩等动力学响应和椎骨应力、韧带伸长率、颅内等效应力、颅内压力、颅骨等效应力等生物力学响应，并进行损伤评估；将肌肉激活水平纳入考虑范畴，研究肌肉紧绷或松弛状态对乘员头颈部损伤的影响。结果表明：采用防冲击姿势可以有效降低头颈部损伤，所提出的双手抱颈式防冲击姿势可以降低颈部轴向力、弯矩、椎骨应力及颅内等效应力，但仍有颈部软组织挫伤及轻微脑震荡的风险；冲击过程中肌肉紧绷状态能有效降低颈椎轴向力、弯矩、韧带伸长率、颅内压力和颅内等效应力。

Abstract:

During emergency landing, passengers using different anti-impact postures often produce different protective effects. A seat/passenger restraint system model based on the THUMS biomechanical dummy is established, comparing head and neck injuries in upright sitting posture, head and hand supported sitting posture, and head supported sitting posture under a 16g horizontal impact. A double-handed neck-holding anti-impact posture was proposed. By analyzing cervical axial tensile, compression force, anterior-posterior bending moment of the neck, the dynamic responses were analyzed, and the biomechanical response of the occupants, including vertebral stress, ligament elongation rate, intracranial equivalent stress, intracranial pressure, cranial equivalent stress, were analyzed. The damage assessment was conducted. Finally, the level of muscle activation was taken into consideration to explore the head and neck injuries of passengers in a state of muscle tension or relaxation. The results show that adopting an anti-impact posture can effectively reduce head and neck injuries, with the proposed double-handed neck-holding anti-impact posture reducing cervical axial force, bending moment, vertebral stress, and intracranial equivalent stress, but still carrying risks of neck soft tissue contusion and mild concussion. Tense muscles during impact can effectively reduce cervical axial force, bending moment, ligament elongation rate, intracranial equivalent stress and intracranial pressure.