Finite Element Simulation And Impact Analysis Of Pedestrian Head Injury Mechanisms For Children

Traumatic head injury caused by traffic accidents takes a large toll of death and disability among children and adolescents. At present, most of head injury research regarding children in domestic is carried out by rigid-body dynamics modeling and assesses injury using data scaling from adult tolerant data. However, child is not a smaller version of adult. The data obtained by scaling method have their limitations. At the same time, rigid body model cannot assess injury that is in tissue level. With the rapid development of computer technology, finite element models offer an important tool to accelerate head injury research. Finite element models of human head can deal with detail anatomy structure of a child head and can reconstruct children pedestrian head impacts. Tissue-level injury and injury mechanism can be explored through stress and strain analysis. Therefore, finite element modeling of the child head can provide a useful theoretical basis for the next step research and possibly helpful counter measure for injury protection.This research constructed a head finite element model dealing with detail anatomy structure from CT scans of a 6-years-old Chinese child. Model validations were performed by comparing responses from simulations with those available cadaver experiment data both from children and adults.The simulation results of the child head finite element model showed that child head injury could be assessed by the computed intracranial pressure, brain principal strain and shear strain. Further studies were carried out on biomechanical responses in different brain and skull locations, different suture positions, and the existence of the deceleration process during pedestrian head impacts.Investigations were also carried out on impact responses of intracranial alternations when tissue material parameters of the head were changed. These tissue parameters included skull stiffness, short-term and long-term shear moduli, attenuation coefficient, and volume modulus of the brain.A design-of-experiments (DOE) was developed to assess head injury in different spots on the hood. The information provides by the DOE study can help the hood design to mitigate pedestrian head impact injury.The mechanism of brain injury and injury assessment evaluations were explored in the current research by finite element modeling of a child head through the pedestrian head impact simulations. The research results showed in this study provide significant practical meaning to understand the mechanism of traumatic brain injury and provide biomechanically sound safety design to prevent the occurrence of brain injury.