A 3D FEM COMPARATIVE STUDY ON THE IMPACT RESPONSE BETWEEN HUMAN HEAD AND NOCSAE HEAD DUE TO FREE FALL

We all enjoy sports be it watching or playing. Concussion is well known topic when it comes sports related injuries. However, concussion and brain injury is not exclusive to sports and outdoor activities. Sometimes, even the impact due to slip and fall at small heights can cause serious damage to the head and brain. This report studies the response generated in the human head model and the commercially use dummy NOCSAE headform due to drop from height of 2, 3, 4 and 5 feet. Earlier studies have related brain kinetics and head kinematics to concussion and traumatic brain injury (TBI). There are also studies that relate the linear and angular accelerations between different commercial dummy head models and the human head model, which were done experimentally. The main purpose of his study is to compare these parameters for the both models analytically using simulations. The linear velocity corresponding to each drop height were calculated and used as input data for the simulations. The impacts were simulated using RADIOSS solver in Hypermesh. Various parameters like contact force, linear acceleration and its components along each of the co-ordinate axes were extracted from the FE analysis. These values were utilized to calculate linear and angular acceleration for the entire models. These values were plotted against tolerance limits for various levels of brain injury. v It was observed that linear acceleration values for both the Human Head model and the dummy NOCSAE Headform confirm each other. Superior impact of the head was found most susceptible to traumatic brain injury followed by lateral impact when linear acceleration was considered as the criteria. The values of angular acceleration though did not represent glaring similarities between the two models, but there was a general trend of increase in angular acceleration with increase in drop height