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The responses of the THOR and the Hybrid-III ATDs to head and neck loading due to a deploying air bag were investigated. Matched pair tests were conducted to compare the responses of the two ATDs under similar loading conditions. The two 50th percentile male ATDs, in the driver as well as the passenger positions, were placed close to the air bag systems, in order to enhance the interaction between the deploying air bag and the chin-neck-jaw regions of the ATDs. Although both ATDs nominally meet the same calibration corridors, they differ significantly in their kinematic and dynamic responses to interaction with a deploying air bag. The difference between the structural designs of the Hybrid-III's and the THOR's neck appears to result in significant differences in the manner in which the loads applied on the head are resisted.

This paper presents a 2D model for frontal vehicle-to-vehicle crashes that can be used for fleet modeling. It presents the derivational details and a preliminary assessment of the model. The model is based on rigid-body collision principles, enhanced adequately to represent energy dissipation and lateral engagement that plays a significant role in oblique frontal vehicle-to-vehicle crashes. The model employs the restitution and the apparent friction in order to represent dissipation and engagement respectively. It employs the impulse ellipse to identify the physical character of the crash, based on the principal directions of impulse. The enhancement of the rigid body collision model with restitution and apparent friction is based on collision simulations that use very simple finite element vehicle representations. The dependence of the restitution and the apparent friction on the incidence angle, the frontal offset, and the mass ratio, as predicted by the 2D model, has been presented.

The paper presents a comparison between the acceleration pulses of vehicle-to-vehicle crash tests with those of different single-vehicle crash tests. The severity of the full frontal rigid barrier test is compared with that of the vehicle- to-vehicle crash test based on average acceleration and time-to-zero-velocity. Based on this a 30mph full frontal rigid barrier test is found equivalent to a 41mph vehicle-to-vehicle crash. A reduced speed of 22mph for full frontal rigid barrier test is found to represent vehicle-to- vehicle crashes with 50%-100% overlap, with each vehicle travelling at 30mph. The paper also presents a comparison of the acceleration pulses from different crash tests based on the pulse shape and the pulse phase cross-correlation. None of the single-vehicle crash tests have been found to resemble vehicle-to-vehicle crashes in terms of the pulse shape and the pulse phase.

Stochastic simulation is used to account for the uncertainties inherent to the system and enables the study of crash phenomenon. For analytical purposes, random variables such as material crash properties, angle of impact, human response and the like can be characterized using statistical models. The methodology outlined in this approach is based on using the information about the probability of random variables along with structural behavior in order to quantify the scatter in the structural response. Thus the analysis gives a more complete picture of the actual simulation. Practical examples for the use of this technique are demonstrated and an overview of this approach is presented.