Analysis Of Thorax Impact Responses Of Six-Year-Old Child Occupants Based On FEM

Although children are not the worst grouping of deaths resulting from road accidents, they are the most vulnerable groups. At the same time, peoples’consciousness for protecting children who are in the car is relatively weak. On the other hand, most of car industries are busy in developing adult protected facilities, while few researches are done for the children restraint system. So, it is important for car industry to develop a child finite element model according to child anatomical structure. We can research child injury mechanism and respond and analyze the different responds to the different test speed through simulating side impact by this model, which is necessary for making safety rules for protecting children and decreasing the rate for child injury.The main content of this study is as follows:1Based on CT imagines of six-year-old child’s thorax, a geometrical model is extracted by using the threshold segmentation method and is divided into surface patches by using reverse engineering software. In this model, it contains ribs, rib cartilage, sternum, lung, heart and so on.2Based on established geometrical models, the finite element model of six-year-old child’s thorax is constructed in mesh software. By comparing the results of FE model of the six-year-old child with the scaling result of experiments of human cadaver impact test in axial load conditions, we get that the results well agree with each other, the validation of the model was verified.3We have a research to simulate side impact by developed child thorax finite element model. In this research we have found that there is stress concentration and easy to be injured in middle ribs, tubercle of rib, oblique fissure and main bronchus.4We have compared front impact and side impact and the result showed that the maximum equivalent stress is77.738Mpa and125.668Mpa in front impact and side impact individually, which means that child thorax is easier to injury in side impact.The researches of side impact simulation through the six-year-old thorax finite element model in this paper help to understand child thorax injury mechanism and provide some information for developing child protective devices. This model also lays a foundation to build a whole child finite element model.