Reconstruction of Automobile/Pedestrian Accidents Using CATAPULT

The Combined Airborne Tumbling Analysis Procedure Using Laws of motion to determine Throw speed (CATAPULT) for a pedestrian is compared to the published results of vehicle/pedestrian impact testing. Testing by the authors demonstrating the mechanics and dynamics of an object tumbling to rest following a known trajectory is presented. It is shown, that although during ground tumbling individual impulses of a pedestrian with the ground are what slow the pedestrian, with restitution occurring between these impulses, the use of an average drag factor of 0.5 over the total distance tumbled produces accurate results for initial speed.