Agnes S. Kim

Relationships between passenger car seat back strength and occupant injury severity in rear end collisions: field and laboratory studies

To determine what effect seat back stiffness and other seat characteristics have on occupant responses, several seats were evaluated in dynamic Hyge rear impact sled simulations. The results of the sled tests indicate that stiffer seats do not have any consistent advantages over yielding seats for the complete range of speeds tested. Even a seat with a head restraint located closer to the center of gravity of the occupants head did not perform better than the baseline seat. Throughout the testing, the most sensitive response to seat design and crash severity was the lower neck extension moment.

BIOFIDELITY OF ANTHROPOMORPHIC TEST DEVICES FOR REAR IMPACT

This study examines the biofidelity, repeatability, and reproducibility of various anthropomorphic test devices (ATDs) in rear impacts. The Hybrid III, the Hybrid III with the Rear Impact Dummy (RID) neck, and the 50th% Thoracic Assessment Device (TAD-50) were tested in a rigid bench condition in rear impacts with velocity changes (delta Vs) of 16 and 24 kph. The results of the tests were then compared to J. Mertz and L.M. Patricks data. The Hybrid III and the Hybrid III with the RID neck were also tested on standard production seats in rear impacts for a delta V of 8 kph. Comparison testing of the Hybrid III and TNO Rear Impact Dummy (TRID) necks were conducted on production seats with different Neck Injury Factor (NIF) scores at delta Vs of 8 and 16 kph. The Hybrid III and the Hybrid III with the pedestrian pelvis were also tested with standard production seats to determine if hip joint stiffness affected the kinematics of the ATD in rear impacts. The standard Hybrid III is a molded pelvis while the pedestrian pelvis is a cut pelvis. It can be concluded that the standard Hybrid III dummy is suitable for rear impact testing. (A) For the covering abstract of the conference see IRRD E201172.

COMPARATIVE PERFORMANCE EVALUATION OF THOR AND HYBRID III

A comparison of the NHTSA advanced dummy, THOR, and the Hybrid III dummy is presented in this paper, based on their performance in four vehicle barrier tests, six HYGE sled tests and twenty-two pendulum chest-impact tests. Various time-histories pertaining to accelerations, angular motions, deflections, forces and moments are compared between the two dummies in light of their design difference. In general, in the vehicle crash tests, the resultant head acceleration and chest deflection in THOR are greater than those in the HYBRID III. The shear, axial force and lateral moment in THORs lumbar are less than those in the Hybrid III in frontal impacts. The differences in the head/chest acceleration and chest deflection could be due to the differences in the construction of the neck and the thorax of the THOR when compared to those of the Hybrid III. The THOR and the Hybrid III have the same level of repeatability in the rear impact sled tests. The THOR is less repeatable in tests involving pendulum impacts on the chest. No major durability problems were identified in the THOR. The construction of the THOR is much more complex than that of the HYBRID III. In order for the THOR to be as easy to use as the HYBRID III, greater effort is needed to improve convenience in terms of data processing, documentation and handling. (A) For the covering abstract see ITRD E106349.

Finite-Element-Based Transfer Equations: Post-Mortem Human Subjects versus Hybrid III Test Dummy in Blunt Impact

In the present study, transfer equations relating the responses of post-mortem human subjects (PMHS) to the mid-sized male Hybrid III test dummy (HIII50) under matched, or nearly-identical, loading conditions were developed via math modeling. Specifically, validated finite element (FE) models of the Ford Human Body Model (FHBM) and the HIII50 were used to generate sets of matched cases (i.e., 256 frontal impact cases involving different impact speeds, severities, and PMHS age). Regression analyses were subsequently performed on the resulting age-dependent FHBM- and HIII50-based responses. This approach was conducted for five different body regions: head, neck, chest, femur, and tibia. All of the resulting regression equations, correlation coefficients, and response ratios (PHMS relative to HIII50) were consistent with the limited available test-based results. Language: en