The Injury Response Ananlysis Of The Occupant Foot During The Vehicle Collision

With the continuous development and progress of human society, vehicle applications are becoming more and more common, and the road traffic safety problem has become a worldwide problem accordingly. Road traffic accidents have become "the victims of the world", while China is one of the world’s largest number of traffic fatalities. How to reduce the damage of occupant and pedestrian in the vehicle collision has gradually become the focus of the world automotive safety research areas. Foot is an important support structure of the human body, and people are paying more attention to the foot injuries in vehicle collisions. Building a foot three-dimensional finite element model with detailed anatomical structure is an important means to study the biomechanics of the foot, which can provide system supporter and theoretical basis for vehicle safety and also has important theoretical significance and application value in the foot injury response analysis.Applying the pre-treatment of software Hypermesh, and referring to the anatomical structure of the foot, the paper based on the existing finite element model of the foot do some further constructions, the main tasks include:adding the finite element mesh of the foot skin; building the soft tissue parts which are unfinished the original model; redrawing and connecting some original grids; constructing more detailed ankle ligaments; refining and improving the grid quality at the same time, building a foot three-dimensional finite element model with high biofidelity. The foot model includes bones, ligaments, muscles, cartilage and soft tissue structures, in which there are 35365 nodes,27601 solid elements and 3163 quadrilateral shell elements.The simulation collision test of the foot is conducted through the application of the finite element analysis software Pam-crash. The initial velocity of 3m/s is applied to the centerline position of the tibia, the 50mm location prior to the centerline of the tibia and the 110mm location prior to the centerline of the tibia, respectively. The simulation results show that the foot model has the predictive ability of the foot injury risks and injury types. Through the test simulation data, we get that the foot bone stress increases with the increase in impact velocity presents a nonlinear relationship. In the foot passive safety research, we found that the energy absorption hurter placed in car floor can effectively reduce the occupant foot injury in the collision process.The construction of the foot finite element model will contribute to the basic feasibility study of the mechanism of the foot injury, and can also contribute to the foot biomechanics response analysis. The results obtained by the simulation test also has a great significance to the research on the tolerance level of the foot injury during the automotive collision; at the same time, the foot finite element model can provide a valid reference value for the automotive active safety design, the automotive passive safety design, as well as the occupant foot protection measures.