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This study was conducted to explore the effect of various combinations of seatbelt-related safety components (namely, retractor pretensioners and load limiting retractors) on the adult rear passenger involved in a frontal collision. The study was conducted on a 50th Male and a 5th Female Hybrid III ATD in the rear seat of a mid-sized sedan. Each ATD was seated in an outboard position with 3-point continuous lap-shoulder belts. On these belts were combinations of pretensioners and load limiters. Since the main objective of this test series was to cross-compare the seatbelt configurations, front seats were not included in the buck in order to avoid uncontrollable variables that would have affected the comparison study if the possibility of contact with the front seat were allowed. Nevertheless, there was a short barrier devised to act as a foot-stop for both ATDs.

A near-side, rear seat side impact component test, was conducted and validated utilizing a SIDIIs anthropomorphic test device (ATD). The test fixture consisted of the rear seat structure, side door, interior trim, and side airbag curtain module. Test parameters were determined from full scale tests including impact speed, angle of impact, and depth of door intrusion. A comparative assessment was conducted between the full scale test and the deceleration sled test including ATD contact with the vehicle interior, contact duration, sequential timing of ATD contact, and dummy injury measures. Validation was achieved so that the deceleration sled test procedure could be utilized for further evaluations.

The use of stiffness coefficients is a well-established method for estimating the crush energy of passenger vehicles involved in frontal impact. This methodology, as well as other crush energy models, have been adapted to take into account laterally offset frontal impacts. On the other hand, methods for estimating crush energy and/or Equivalent Barrier Speed (EBS) of frontal underride collisions (vertical offset) require more development. Further, there is a need for crush energy estimation models for cases of combined lateral and vertical offset impacts as well. The objective of this research is to computationally explore the effect of lateral offset, as well as combined lateral and vertical offset on the crush energy absorption of a car in a frontal collision and the feasibility of a generalized stiffness-coefficient-based EBS approximation approach.

The rear seat occupant has been the subject of an increasing number of research efforts in recent years. However, the majority of the research has focused on frontal impact, while there are also a number of studies concerned with low to moderate delta-V rear impact. Very limited work exists regarding the fate of the rear seat occupant involved in high-severity rear impact, especially when utilizing the BioRID anthropomorphic test device (ATD). Furthermore, it is evident that the out of position rear occupant, as defined by leaning forward prior to rear impact, is also of relevance to this line of research. The objective of this study is to explore and compare the response of BioRID and 50 th percentile Hybrid III in conjunction with the effects of head restraint geometry and the occupant seating configuration (normal seating versus forward leaning) in high-severity rear impact tests.

Truck-trailers are required to have rear impact protection guards per Federal Motor Vehicle Safety Standards 223 and 224. The standards define the minimum strength and energy absorption requirements at the guard component level, while allowing the guard manufacturer to use a rigid test fixture when certifying the guard. Due to the limitations inherent in “rigidizing” the under-structure of a trailer, often some amount of deformation in the supporting structures is tolerated when certifying a guard. Hence there is a tendency to certify the impact guard as a “guard system” composed of guard members and the support (mounting) structures. In this paper, a previously validated 1990 Ford Taurus FE model was used to analyze the effect of compliance in the guard support members on its dynamic performance. Two guard systems, one with rigid supports and another with some compliance in the supports were modeled.

FMVSS 223 and 224 set standards for “Rear Impact Protection” for trailers and semi-trailers with a gross weight rating greater than 10000 pounds. A limited amount of experimental data is available for evaluating the different performance attributes of rear impact guards. The crash tests are usually limited to fixed parameters such as impact speed, guard height, strength and energy absorption, etc. There also seems to be some misunderstanding of the interdependence of guard strength and energy absorption, and their combined effect on the guard's ability to limit underride while keeping occupant acceleration forces in a safe range. In this paper, we validated the Finite Element (FE) model of an existing rear impact guard against actual FMVSS 223 tests. We also modified a previously evaluated FE model of a 1990 Ford Taurus by updating its hood geometry and material properties.

This study provides a preliminary investigation of occupant kinematics for rear seat occupants involved in high-severity rear impacts. The effect of a seatbelts equipped with or without a pyrotechnic pretensioner on restraining the rear seat adult occupant was evaluated. Further, the study examined the result of the occupant's seating alignment by comparing a Nominal Seating Position (NSP) to an occupant whose torso would be rotated forward to be placed in a Moderately Displaced Position (MDP) prior to impact. A series of eight sled tests were performed using a deceleration sled subjected to a delta-V of 30 mph. Instrumented HIII 50th and 5th ATDs were positioned in the outboard, rear seating positions. The study found that pretensioners had little effect on the occupant kinematics of rear seat occupants in either the NSP or the MDP. But, there were marked differences in kinematic evaluations between the occupant seating alignment configurations.

The current study was designed to compare the surface anatomy of the knee for different human subject anthropometries using a 3-D, non-contact digitizer which converted the anatomy into point clouds. The subjects were studied at flexion angles of 60, 90, and 120 degrees. Multiple subjects fitting narrow anthropometrical specifications were studied: 5th percentile female, 50th percentile male, and 95th percentile male. These data were then compared to a corresponding anthropometrical crash dummy knee which served as an unambiguous control. Intersubject human comparisons showed surface geometry variations which were an order of magnitude smaller than comparisons between the human and dummy knee. Large errors between the human and dummy were associated with the muscle bulk proximal and distal to the popliteal region and the rounder shape of the human knee.

The first objective of this paper was to evaluate a public domain finite element (FE) model of a 1990 Ford Taurus from the perspective of crush energy absorption. The validity of the FE model was examined by first comparing simulation results to several published full-frontal crash tests. Secondly, the suitability of the model for underride simulation was evaluated against two series of full-scale crash tests into vertically offset rigid barriers. Next, the evaluated FE model was used to pursue the main objective of this work, namely to develop an approach for estimating underride crush energy. The linear-spring methodology was adopted whereby the underride crush stiffness was determined by relating the residual upper radiator support deformation to crush energy. An underride crush stiffness estimation method was proposed based on modifying the full-frontal stiffness coefficients.