加速度造成不对称周边视力丧失的仿真研究

A simulation study with finite element model on the unequal loss of peripheral vision caused by acceleration

复合高过载加速度将导致人体不对称的周边视力丧失,会成为飞行安全的极大隐患。基于此,本文提出用数值仿真的手段探究加速度对双眼视力的影响,以期探索复合加速度造成人体不对称周边视力丧失的力学机制。本文首先将计算机断层扫描(CT)的成年人头骨序列图像进行三维重建,得到含有双眼眼眶的头骨仿真模型。再将之前建立的单眼球模型进行镜像,得到双眼模型,匹配至头骨模型中,并填充脂肪加以完善。对该模型分别加载头-足方向的加速度载荷(Gz)、右-左方向的加速度载荷(Gy)、胸-背方向的加速度载荷(Gx)以及三个方向的复合加速度载荷,利用显式动力学算法,得到视网膜的动态力学响应。仿真研究结果表明,复合加速度作用下双眼应变相差25.7%,其分布特征具有明显差异。本文通过建立双眼有限元模型,为探索复合加速度造成不对称的周边视力丧失的机制性研究提供一种新的手段。

An unequal loss of peripheral vision may happen with high sustaining multi-axis acceleration, leading to a great potential flight safety hazard. In the present research, finite element method was used to study the mechanism of unequal loss of peripheral vision. Firstly, a 3D geometric model of skull was developed based on the adult computer tomography （CT） images. The model of double eyes was created by mirroring with the previous right eye model. Then, the double-eye model was matched to the skull model, and fat was filled between eyeballs and skull. Acceleration loads of head-to-foot （Gz）, right-to-left （Gy）, chest-to-back （Gx） and multi-axis directions were applied to the current model to simulate dynamic response of retina by explicit dynamics solution. The results showed that the relative strain of double eyes was 25.7% under multi-axis acceleration load. Moreover, the strain distributions showed a significant difference among acceleration loaded in different directions. It indicated that a finite element model of double eyes was an effective means to study the mechanism of an unequal loss of peripheral vision at sustaining high multi-axis acceleration.