飞行过程中头盔对飞行员颈部损伤的影响

为研究飞行过程中不同头盔对飞行员颈部损伤的影响，基于头颈部多刚体动力学模型，对急转弯及稳定盘旋飞行工况下4种头盔情况开展了动力学分析。得到了不同头盔作用下颈部肌肉力、椎间力、力矩及颈部损伤指数N_ij的变化规律，对不同头盔作用下的颈部损伤风险进行了评估。结果表明:所建立的头颈部模型与实验结果较为吻合，可以用来进行仿真模拟分析；相同飞行工况下，B头盔的佩戴使得头部质心前移，增加了颈部前屈时斜方肌的肌肉力；对于同一颈椎节段，B头盔的轴向压缩力最大，而C头盔导致的后伸力矩最大；在所有的计算工况中，上下颈椎的颈部损伤指数N_ij均小于0.5，满足航空领域的安全要求；B头盔和C头盔的质量相近，而B头盔质心位置靠前，C头盔靠后，说明头盔质心的前后位置会对颈部的损伤产生重要影响。研究结果可为飞行员头盔的设计优化及其对颈部损伤的影响提供研究支撑。 

Effect of helmet on neck injury of pilots in flight

To explore the effect of helmet on neck injury of pilots in-flight, numerical simulations were carried out on four different helmets during sharp turn and stable hover condition based on the established head-neck multi-body dynamic model. Combining the muscle force, intervertebral force and moment, and the neck injury index N_ij, the neck injury of pilots was evaluated and predicted. The results show that the dynamic responses of the model are in agreement with the experimental results, with fair bio-fidelity. In the same flight condition, the wearing of helmet B shifts the center of head forward and increases the muscle force of the trapezius accordingly. For the same cervical segment, the axial compression force for helmet B and the extension moment for helmet C is maximum respectively. The value of N_ij for all simulated conditions is less than 0.5, which conforms to the safety requirements in aviation. The mass of helmet B and helmet C are close, while the mass center of helmet B is forward compared to helmet C, which indicates the anteroposterior position of helmet has an important effect on neck injury. This study provides insights for the optimization of pilot's helmet and its effect on pilot's neck injury.