Modelling and impact analysis of football player head with helmet toward mitigating brain concussion

In recent years, increasing concussions among American football players have drawn attention and concerns regarding safety of today's football helmets. This study investigates the effects of concussive impact forces on the brain of football players and the shock absorbing performance of actual football helmets. Initially, the mechanical properties of typical helmet materials were obtained through compression tests and hysteresis loop experiments. Next, a lumped-mass model was developed to physically describe both the head and helmet together against an impact load, and the brain response was obtained from the semi-analytical analysis. To extract more information such as strains and wave propagations within the brain, a detailed continuum model was constructed and the response of the brain was analysed by using the finite element method. A realistic impact load was obtained from a case study of actual football play. Our experimental data along with biomechanical data of the head and brain from the available literature were incorporated into our modelling and analyses. The results indicated that the accelerations and strains in the brain were both above the concussion thresholds and that current football helmet designs may not protect players against concussion.