Development of the MADYMO Race Car Driver Model for Frontal Impact Simulation and Thoracolumbar Spine Injury Prediction in Indianapolis-type Racing Car Drivers

This paper describes the results of a project to develop a MADYMO occupant model for predicting thoracolumbar (TL) spine injuries during frontal impacts in the Indianapolis-type racing car (ITRC) environment and to study the effect of seat back angle, shoulder belt mounting location, leg hump, and spinal curvature on the thoracolumbar region. The newly developed MADYMO Race Car Driver Model (RCDM) is based on the Hybrid III, 50^th percentile male model, but it has a multi-segmented spine adapted from the MADYMO Human Facet Model (HFM) that allows it to predict occupant kinematics and intervertebral loads and moments along the entire spinal column. Numerous simulations were run using the crash pulses from seven real-world impact scenarios and a 70 G standardized crash pulse. Results were analyzed and compared to the real-world impacts and CART HANS^® model simulations. The Race Car Driver Model showed good kinematic correlation with the Human Facet Model and Hybrid III, 50^th percentile male model. In addition, the RCDM predicted lower thoracolumbar loads and moments in the more upright, 25-degree recline position versus the normal, 45-degree recline position. Overall, simulations conducted in this study demonstrate the strong influence of spinal geometry and seating position on spine injury prediction outcomes during frontal impacts.