Research On Human Body Injury Based On The Statistics Of Vehicle-to-vehicle Frontal Impact

In the two vehicle frontal impact, there are a lot of differences in vehicle mass, type and geometry of the front-end structure between the two crashed vehicles. The variables like the impact speed, impact direction and location are also different in each case. Based on the statistics, it is important to stduy the influence of these parameters on the injury risk suffered by the occupants. However, the Human Body Model(HBM) which has the characteristics of the human organs, bones and muscle in details is developed according to the real human body and it could presents the human injuries’ mechanisms and patterns when the injuries happened. Using the HBM to analyze the occupants’ injuries and assist the development of the restraint system has been a trend of the passive safety research.This research compared the driver’s severe injury risk under the different impact conditions based on the database of the NASS-CDS between Car to Car and Car to LTV, respectively. The car-to-LTV finite element(FE) model was built and the nodes’ boundary information of the car was collected as an input of the sled model which carrying THUMS using the sub-modelling method. It is a precise and high-efficient way to simulate the human body injuries. Then the injuries of the THUMS’s head, chest and lower limbs were analyzed in details in three impact locations that were chose to study based on the statistics above.The traffic accidents statistics show that the mass ratio is one of the important factors that have a great influence on the occupants’ severe injury risks. Both the drivers in two vehicles got the higher severe injury risks in the impact direction of the 12 o’clock than that in 11 and 1 o’clock. In the Car to Car impact type, the driver in lighter vehicle secured less relative severe injury risk than the one in heavier vehicle as the impact locations decreased. While in the Car to LTV impact type, the car driver would secure more injury risks than the one in LTV no matter in which impact locations is.The injuries analysis of the HBM show that the peak acceleration of the head would reduce as the impact locations decreased. The Maximum Principal Strain(MPS) of the brain mainly concentrated below the 10% under the three impact locations. The maximum deflection of the chest appeared at the right place of the middle chest and value reduced as the impact locations decreased. Meanwhile, the maximum value of the Von Mises Stress(VMS) in chest bones reached more than 100 MPa. The axial forces of the driver’s femurs are far less below the limitation level of 10 k N. With the narrowing of the impact locations, the axial forces of the left femurs are increasing and the axial forces of the right femurs are decreasing. While the maximum value of the VMS in left tibia and fibula are less than that in right tibia and fibula.