Methodology for estimating thoracic impact response in frontal crash tests

This study has investigated the feasibility of estimating chest acceleration from the pelvic acceleration and shoulder belt forces measured on a vehicle occupant exposed to a frontal crash. The method of estimating chest acceleration is based upon a simple two-mass one-dimensional model of a vehicle occupant in which pelvic acceleration and shoulder belt force are applied as forcing functions. The predictive power of the model was evaluated by comparing the estimated and measured chest acceleration of 18 Hybrid-III crash test dummies subjected to 56 km/hr full frontal barrier crash tests. The crashtest dummies were restrained by airbags and three-point belt systems with pretensioners and load-limiting shoulder belts. The combined loads exerted on the chest by the pelvis and the shoulder belts were shown to be a reasonable estimate of force on the chest early in the crash event prior to significant airbag loading.