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The capability to predictively simulate occupant dynamics in vehicle rollover crashes using the Articulated Total Body (ATB/CVS) model was validated using the results of two controlled automobile rollover crash tests. The ATB model requires the occupant's inertial, geometric, and resistive joint torque properties, the vehicle interior geometry and motion, the contact characteristics for the occupant and vehicle interactions, and the seat belt characteristics. The validation was done by first simulating one test and adjusting the contact and belt properties to obtain good comparison with the test results. Then subsequent tests were simulated using the same properties, but changing only the input vehicle kinematics. Each occupant simulation used the standard Hybrid III data set and measured vehicle interior geometry. The vehicle kinematics were generated by simulating the vehicle dynamics with the ATB model. In one rollover, roof crush significantly affected the occupant's motion.

To demonstrate the Articulated Total Body (ATB) model's capability to predict complex rollover accidents, a rollover accident was selected from the National Accident Sampling System (NASS) and simulated. This paper focuses on the simulation of the vehicle's dynamics which can in turn be used to specify the vehicle motion for occupant simulations. The selected accident case involved a pickup truck, crashing at high speed and completing three rolls. The pickup truck was modeled as a single rigid segment with fifteen contact hyperellipsoids rigidly attached to it. These hyperellipsoids were sized and positioned to approximate the exterior surfaces of the pickup truck. The force-deflection functions were defined based upon previous simulations of rollover tests. The initial conditions were defined to match the data in the NASS accident report as closely as possible.