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Rollover events involving multiple revolutions are dynamic, high-energy, chaotic events that may result in occupant injury. As such, there is ongoing discussion regarding methods that may reduce injury potential during rollovers. It has been suggested that increasing a vehicle's roof strength will mitigate injury potential. However, numerous experimental studies and published field accident data analyses have failed to show a causal relationship between roof deformation and occupant injury. The current study examines occupant kinematics and injury mechanisms during dolly rollover testing of a vehicle with a high roof strength-to-weight ratio (SWR = 4.8). String potentiometers and high-speed video cameras were used to capture and quantify the dynamic roof motion throughout the rollover. Instrumented Anthropomorphic Test Devices (ATDs) in the front occupant positions allowed for the assessment of occupant kinematics, loading, and injury mechanics during the rollover event.

Considerable research has been dedicated to establishing the amount of energy absorbed during different types of collisions. In the early 1960’s, motor vehicle manufacturers began conducting barrier crash tests consistent with SAE suggested procedures. This allowed investigators to establish the amount of energy that went into metal deformation in the tested vehicle. Over the years, there have been many advances in establishing the amount of crush energy in a particular accident, including the development of several computer programs. Four two-vehicle, single-moving rear-impact crash tests were conducted to compare the effect of override and offset. Override comparisons were made using a moving, rigid barrier or a heavy truck as the impactor, and each pair of tests having either offset or full rear engagement. All four tests were conducted using a like make and model four-door sedan as the target vehicle. Each test had the same available crush energy for the car.

Engineering Dynamics Corporation (EDC) recently updated the Human, Vehicle, Environment (HVE) software program to enable modeling of passenger cars and light trucks towing trailers. This paper reports on a comparison between the HVE EDSMAC4 collision module of the 3-dimensional computer simulation program and instrumented crash tests, in which one vehicle in each test was a pickup truck pulling a trailer. Use of the EDSMAC4 trailer model was found to provide better correlation between the simulation and test damage profiles, rest positions, vehicle trajectories, velocities, and Delta-V. It was also determined that the NHTSA-derived stiffness coefficients are sensitive to the impact configuration and depending on the impact configuration, it may be necessary to refine the coefficients according to the configuration.

In rollovers, belted occupants sustain a lower fatality rate compared to unbelted occupants primarily due to lower risk of partial or full ejection. However, seat belt and occupant compartment designs found in most current vehicles do not prevent head contact with the vehicle interior during a rollover because of occupant torso and head excursion that result from the rollover dynamics. An experimental study was conducted to simulate the airborne phase of a rollover. The goals of this study were to: 1) quantify the effect of restraint anchor locations and belt component designs in reducing head excursion, and 2) to better correlate the response between humans and an Anthropomorphic Test Device (ATD) during the high angular roll rate of the airborne phase of a rollover. A Head Excursion Test Device was designed to rotate a restrained occupant about an axis to approximate the inertial loading experienced during the airborne phase of a rollover.