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A comparison of the NHTSA advanced dummy and the Hybrid III is presented in this paper based on their performance in twenty four frontal impact sled tests. Various time histories pertaining to accelerations, angular velocities, deflections and forces have been compared between the two dummies in light of their design differences. This has lead to some understanding about the differences and similarities between the NHTSA advanced dummy and the Hybrid III. In general, the chest as well as the head motion in the NHTSA advanced dummy are greater. The lumbar moments in the NHTSA advanced dummy are lower than that in the Hybrid III. The upper and lower spine segments in the NHTSA advanced dummy, generally rotate more than the spine of the Hybrid III.

The SID-IIs is a small [s], second-generation [II] Side Impact Dummy [SID] which has the anthropometry of a 5th percentile adult female. It has a mass of 43.5 kg, a seated height of 790 mm, and over 100 available data channels. Based on the height and mass, this is equivalent to an average 12-13 year old adolescent. The state-of-the-art SID-IIs has special application in evaluating the performance of side impact airbags. The dummy has undergone prototype testing and will shortly be available for worldwide evaluation. This paper describes the technical details of the dummy, its biomechanical design targets, how well it met those targets, its validation requirements, and its instrumentation. The dummy is the product of a joint development agreement between the Occupant Safety Research Partnership (OSRP) of USCAR and First Technology Safety Systems.

While evaluating the BIOSID advanced side impact dummy in full scale crash tests, we noticed higher than expected abdominal rib deflections. This finding led to a search to determine whether these deflections were an artifact of the dummy or whether the dummy was indicating that some portion of the vehicle side, in the area of the armrest, was laterally stronger than expected. Many armrests/trim panels were procured and both quasi-statically and dynamically tested using newly-devised test procedures. A team was formed to evaluate armrest/trim panel construction and to develop a biomechanically-based laboratory test procedure to help determine the effects of design and material changes. This team continues to function and a spin-off team is seeking to develop analytical predictive tools to allow speedier development of armrest/trim panels attuned to the new test procedure.

The NHTSA issued an Advanced Notice of Proposed Rule Making (ANPRM) during the third quarter of 1988. Research tests on a mid-size car and a light truck upper interior surfaces were conducted using a NHTSA research test procedure to help assess the variables associated with this procedure. As a result of these tests, the authors recommended a revised test using a spherical headform with normal-to-surface impacts. This revised procedure was used in a second test series on a similar mid-size sedan. The results of these tests are shown.

Side impact collisions account for about 29% of all vehicle occupant fatalities and for about one-fifth of all the “harm” to vehicle occupants. This paper addresses many aspects of side impact induced injuries which vehicle planners and designers may choose to consider during the evolution of a vehicle design. The proposed NHTSA side impact test, side impact dummies, the biomechanics of different human body areas and general concepts for increased occupant protection are discussed from a theoretical point of view. It is believed that this paper or a future update of it, can only become a useful tool when there is general agreement that it reflects solid biomechanical direction which in turn, can be reflected in actual, practicable, responsible hardware design.

Two-point restrained and unrestrained 50 percentile male dummy tests were conducted on the Hyge Sled in a typical package configuration at 56 and 48 km/h respectively, with corrugated paper knee bolster simulations located close and far from the dummy's knees. The effect of bolster location on the various dummy measurements were compiled and trends were evaluated. Comparisons also were made between the performance of the Hybrid II and Hybrid III dummies. The Ford “Chest Load Distribution Transducer” also was used to infer changes in loading patterns on the lower rib cage as bolster spacing was varied. Bolster location affected many of the dummy measurements for the restrained tests and indicated the possible desirability for even further dummy measurement capability than used in this test program. Bolster location effects were masked in the unrestrained dummy tests by extreme dummy kinematics.

This paper reports on the injuries to the head, neck and thorax of fifteen child surrogates, subjected to varying levels of sudden acceleration. Measured response data in the child surrogate tests and in matched tests with a three-year-old child test dummy are compared to the observed child surrogates injury levels to develop preliminary tolerance data for the child surrogate. The data are compared with already published data in the literature.

A test fixture for use on the Hyge Sled was fabricated to NHTSA specifications, matching the fixture used at Heidelberg University to measure forces on cadavers in side impact configurations. Tests were conducted at 16, 22, 24, and 32 km/h to simulate both the APR cadaver drop tests and Heidelberg sled tests. Comparisons to the cadaver data were made with the Ford Side Impact Body Block and the APR and SID dummies. Test results are shown and discussed.

The current Part 572 50th percentile male dummy's chest and legs only indirectly and incompletely measure the forces acting upon them - by spinal acceleration for the chest and by mid-femur axial force for the legs. A new chest and set of legs have been designed and are in experimental use in a Part 572 dummy which far more completely measure the forces acting upon them during crash testing. CHEST LOAD-DISTRIBUTION TRANSDUCER - Through three independent beams, with a small triaxial load cell located at the end of each beam, the vector direction and magnitude of the load can be measured at six key locations on the rib cage during the dynamic testing of restraint systems. The effect of small changes in the restraint system on the forces experienced by the thoracic area of the dummy can now be quantified. Some of the experimental results are discussed.

The head, chest and femurs of three Hybrid II dummies were impacted with a ballistic pendulum at various angles to determine what differences in accelerometer and femur load cell output would result for a constant energy input. Also evaluated were suspicious tension loads in the femur load cell output when the legs were subjected to obvious off-center impacts during crash tests. It was found that the dummy legs can be subjected to very high torsion and bending loads which can have a significant effect on the femur load cell axial load outputs.

The results of recent dynamic load measurements on human skull and patella bone, conducted with less-than-1-sq-in. penetrators, are discussed in relation to previously reported skull impact data from larger contact areas. These medical data are compared to the dynamic response of a large variety of natural and synthetic plastic materials, for use in trauma-indicating headform and kneeform design. Several bodyform designs are proposed as research tools.

The injury-reducing functions of crash padding are discussed as they relate to head impact. The bony structure of the cranial vault (above eyebrows) is strong under localized impact compared with the face. Padding used to protect the cranial vault from impact has the primary function of absorbing energy to reduce the possibility of brain damage. On the other hand, padding for facial protection has the primary function of providing uniform load distribution on the face. The pad understructure then supplies the needed energy absorbing capacity. Test procedures to measure both energy absorption and load distribution are described, and evaluation criteria are shown. Other factors that affect padding, such as temperature and cover stock material, are discussed.