The development, validation and application of a finite element upper extremity model subjected to air bag loading.
The development, validation and application of a finite element upper extremity model subjected to air bag loading.
复制标题
气囊加载有限元上肢模型的开发、验证和应用。
DOI：
10.4271/2003-22-0004
复制
发表时间：
2003
影响因子：
--
通讯作者：
J. Crandall
中科院分区：
文献类型：
--
作者：
L. van Rooij;R. Bours;J. van Hoof;J. J. Mihm;S. Ridella;C. Bass;J. Crandall
在碰撞时肢体靠近气囊模块的情况下，正面和侧面气囊都可能对上肢造成伤害。目前的假肢在气囊载荷下表现出了定性的正确运动学，但在长骨弯曲和骨折时缺乏生物逼真度。因此，需要一种有效的研究工具来研究气囊加载中涉及的损伤机制，并判断新气囊设计的改进。本研究的目的是建立一个有效的数值模型，表现出正确的全球运动学以及局部组织变形和骨折的各种影响条件下开始。该模型的开发包括创建一个足够准确的有限元网格，适应材料性能从文献到本构模型和关节关节位置的运动约束的定义。为了使该模型适用于全尺寸模拟，它与计算效率高的人体模型相结合。该模型进行了验证，对现有的尸体实验，包括静态和动态三点弯曲测试的手臂和前臂，以及正面气囊前臂的冲击测试。该模型的敏感性，在安全气囊的属性和上肢方向的变化进行了论证，通过执行参数研究。结果表明，前臂骨折的风险大大增加，接近部署正面气囊和气囊的侵略性，这对应于实验结果。然而，增加前臂旋后角度对前臂骨折的发生有保护作用。总之，所开发的模型被证明是一个有用的研究工具，可以研究将正面安全气囊改变为上肢负载环境后伤害严重程度的趋势。
Both frontal and side air bags can inflict injuries to the upper extremities in cases where the limb is close to the air bag module at the time of impact. Current dummy limbs show qualitatively correct kinematics under air bag loading, but they lack biofidelity in long bone bending and fracture. Thus, an effective research tool is needed to investigate the injury mechanisms involved in air bag loading and to judge the improvements of new air bag designs. The objective of this study is to create an efficient numerical model that exhibits both correct global kinematics as well as localized tissue deformation and initiation of fracture under various impact conditions. The development of the model includes the creation of a sufficiently accurate finite element mesh, the adaptation of material properties from literature into constitutive models and the definition of kinematic constraints at articular joint locations. In order to make the model applicable for full-scale simulations, it was coupled with a computationally efficient human model. The model was validated against available cadaver experiments, including static and dynamic three-point-bending tests to the arm and forearm, as well as frontal air bag to forearm impact tests. The sensitivity of the model to changes in air bag properties and upper limb orientation are demonstrated by performing parametric studies. It is shown that the risk of forearm fracture increases substantially with proximity to the deploying frontal air bag and air bag aggressiveness, which corresponds to experimental findings. However, it is shown that increasing the forearm supination angle is protective for the occurrence of forearm fracture. In conclusion, the developed model proves to be a useful research tool to investigate trends in injury severity as a result of a changing frontal air bag to upper extremity loading environment.