Weng Yuhu, Bian Kewei, Gunasekaran Kalish, Gholipour Javad, Vidal Charles, Mao Haojie
Mechanical and Materials Engineering, Faculty of Engineering, Western University, London, Ontario, Canada.
National Research Council, National Research Council Canada - Aerospace Research Center 2107 Chemin de la Polytechnique, Montréal, Québec H3T 1J4, Canada.
J Biomech. 2021 Nov 9;128:110748. doi: 10.1016/j.jbiomech.2021.110748. Epub 2021 Sep 10.
Understanding small remotely piloted aircraft system (sRPAS) to human head impacts is needed to better protect human head during sRPAS ground collision accidents. Recent literature reported cadaveric data on sRPAS to human head impacts, which provided a unique opportunity for developing validated computational models. However, there lacks an understanding of skull stress and brain strain during these impacts. Meanwhile, how slight changes in sRPAS impact setting could affect human head responses remains unknown. Hence, a representative quadcopter style sRPAS finite element (FE) model was developed and applied to a human body model to simulate a total of 45 impacts. Among these 45 simulations, 17 were defined according to cadaveric setting for model validation and the others were conducted to understand the sensitivity of impact angle, impact location, and impacted sRPAS components. Results demonstrated that FE-model-predicted head linear acceleration and rotational velocity agreed with cadaveric data with average predicted linear acceleration 4.5% lower than experimental measurement and average predicted of rotational velocity 2% lower than experimental data. Among validated simulations, high skull stresses and moderate level of brain strains were observed. Also, sensitivity study demonstrated significant effect of impact angle and impact location with 3° variation inducing 30% changes in linear acceleration and 29% changes in rotational velocity. Arm-first impact was found to generate more than two times higher skull stresses and brain strains compared to regular body-shell-first impact.
为了在小型遥控飞机系统（sRPAS）地面碰撞事故中更好地保护人类头部，需要了解sRPAS对人类头部的撞击情况。最近的文献报道了sRPAS对人类头部撞击的尸体数据，这为开发经过验证的计算模型提供了独特的机会。然而，目前尚缺乏对这些撞击过程中颅骨应力和脑应变的了解。同时，sRPAS撞击设置的微小变化如何影响人类头部反应仍然未知。因此，开发了一个具有代表性的四旋翼式sRPAS有限元（FE）模型，并将其应用于人体模型以模拟总共45次撞击。在这45次模拟中，17次是根据尸体设置定义的，用于模型验证，其余的则是为了了解撞击角度、撞击位置和被撞击的sRPAS部件的敏感性。结果表明，有限元模型预测的头部线性加速度和旋转速度与尸体数据一致，预测的平均线性加速度比实验测量值低4.5%，预测的平均旋转速度比实验数据低2%。在经过验证的模拟中，观察到了较高的颅骨应力和中等程度的脑应变。此外，敏感性研究表明，撞击角度和撞击位置有显著影响，3°的变化会导致线性加速度变化30%，旋转速度变化29%。发现手臂先撞击产生的颅骨应力和脑应变比常规的身体外壳先撞击高出两倍以上。
