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This article discusses steps to predictively estimate the responses of Anthropomorphic Test Device (ATD) in a side impact event, based on a Side Airbag (SAB) Force-Deformation (F-D) characteristics derived from the linear impactor test. A critical load management challenge that has been used to assess this predictive response process is the oblique pole impact test - part of the FMVSS 214 protocol. In this scenario, the ATD is assumed to have a free travel until it is stopped by the crushed and stacked up door against the rigid pole. Three critical energy management paths involved to manage the kinetic energy of the ATD at impact are assumed at the onset, namely, the door trim crush, ATD torso loading and most important efficient energy management of the SAB at a controlled force level. The SAB energy management is assumed critical and tied with the final response of the test ATD.

This paper discusses steps for identifying, evaluating and recommending a quantifiable design metric or metrics for Side Airbag (SAB) development. Three functionally related and desirable attributes of a SAB are assumed at the onset, namely, effective SAB coverage, load distribution and efficient energy management at a controlled force level. The third attribute however contradicts the “banana shaped” force-displacement response that characterizes the ineffective energy management reality of most production SAB. In this study, an estimated ATD to SAB interaction energy is used to size and recommend desired force-deformation characteristic of a robust energy management SAB. The study was conducted in the following three phases and corresponding objectives: Phase 1 is a SAB assessment metric identification and estimation, using a uniform block attached to a horizontal impact machine.

The Insurance Institute for Highway Safety (IIHS) has begun a new side impact crashworthiness evaluation of vehicles, using tests that represent impacts from large trucks and sport utility vehicles. This test protocol, intended as consumer information rating of vehicles, adds new challenges to current side impact crashworthiness development in both the vehicle structure and dummy responses. Available tests data seem to indicate that safety enhancement features that work for current US-SID and Euro-SID may not work for the SID-IIs dummy that is used in the IIHS test protocol, but may in fact deteriorate dummy response. This may partly be explained by the fact that the SID-IIs is not a scaled down dummy of either the US-SID or the Euro-SID. This paper presents and discusses the results from sled tests conducted to investigate countermeasures that will help improve the response of the SID-IIs in the Insurance Institute's side impact test.

A three-step vehicle development process for crashworthiness in the frontal impact test mode is proposed in this paper. The three steps are: (a) System identification, (b) Initial Component Sizing and (c) Detailed Analyses, System Integration and Optimization, which suggests the use of FEA methods to do detailed analyses, system integration and design optimization as applicable in the later part of the process when more vehicle details are known. This paper discusses this process and the results achieved. Limitations inherent in this approach are also identified and discussed. The emphasis is on the development of the structural aspects of a vehicle for a high star rate performance in the NHTSA NCAP impact test mode.

In the continuing automotive design trends towards greater lightness, the energy absorption capacity and low deformability of the knee bolster system in a front end collision, must not be compromised for light material guages. In order to minimize knee injury to both the driver and the front seat passenger, it is necessary to have a knee bolster system that absorbs as much of the impact energy as possible. Moreover, in order to minimize chest injury to the driver, the driver side knee bolster must not come in contact with the steering column during impact. In a study conducted by us, a simplified approach was used to evaluate the energy absorption capacity and the deformations of the knee bolster system under frontal impact. The analysis was performed using a nonlinear dynamic finite element computer code, DYNA3D, developed at the Lawrence Livermore National Laboratory.