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We have recently obtained experimental data and used them to develop computational models to quantify occupant impact responses and injury risks for military vehicles during frontal crashes. The number of experimental tests and model runs are however, relatively small due to their high cost. While this is true across the auto industry, it is particularly critical for the Army and other government agencies operating under tight budget constraints. In this study we investigate through statistical simulations how the injury risk varies if a large number of experimental tests were conducted. We show that the injury risk distribution is skewed to the right implying that, although most physical tests result in a small injury risk, there are occasional physical tests for which the injury risk is extremely large. We compute the probabilities of such events and use them to identify optimum design conditions to minimize such probabilities.

A comparison of the 50th percentile male THOR-LX and Hybrid III 50th percentile male dummy lower leg was conducted via component and full scale barrier testing. In the component tests, isolated THOR-LX and Hybrid III lower legs were impacted in two different test set-ups where the tibia was impacted at three different impact points. The foot without a shoe was impacted in two different test set-ups at six different impact points. A shoe impact study was also conducted to determine the effect of a shoe on the results and to determine how many impacts a shoe can withstand at each point before properties of the shoe begin to change. For these tests, the THOR-LX and Hybrid III lower legs were repeatedly impacted at four different points on the foot with a shoe. For the full scale barrier testing, the THOR-LX or Hybrid III lower legs were attached to a belted Hybrid III 50th percentile male dummy. The dummy was positioned in a compact car for each test.

The WorldSID is a new, advanced Worldwide Side Impact Dummy that has the anthropometry of a mid-sized adult male. It has a mass of 77.3 kg, a standing height of 1753 mm and a seated height of 911 mm. Almost every body region is a new, innovative design, setting the WorldSID apart from all existing side impact dummies. It incorporates over 200 available data channels, in-dummy wiring, and an in-dummy data acquisition system (DAS). The dummy is designed to be used for research and future harmonized side impact test procedures as defined by the International Harmonized Research Activities (IHRA) and other organizations. It is expected to have a biofidelity classification of “good” to “excellent” using the International Organization for Standardization (ISO) dummy classification scale. The WorldSID will be the basis for the future development of a side impact dummy family.

Among all the vehicle rollover test procedures, the SAE J2114 dolly rollover test is the most widely used. However, it requires the test vehicle to be seated on a dolly with a 23° initial angle, which makes it difficult to test a vehicle over 5,000 kg without a dolly design change, and repeatability is often a concern. In the current study, we developed and implemented a new dynamic rollover test methodology that can be used for evaluating crashworthiness and occupant protection without requiring an initial vehicle angle. To do that, a custom cart was designed to carry the test vehicle laterally down a track. The cart incorporates two ramps under the testing vehicle’s trailing-side tires. In a test, the cart with the vehicle travels at the desired test speed and is stopped by a track-mounted curb.

The objective of this study was to optimize the occupant restraint systems for a light tactical vehicle in frontal crashes. A combination of sled testing and computational modeling were performed to find the optimal seatbelt and airbag designs for protecting occupants represented by three size of ATDs and two military gear configurations. This study started with 20 sled frontal crash tests to setup the baseline performance of existing seatbelts, which have been presented previously; followed by parametric computational simulations to find the best combinations of seatbelt and airbag designs for different sizes of ATDs and military gear configurations involving both driver and passengers. Then 12 sled tests were conducted with the simulation-recommended restraint designs. The test results were further used to validate the models. Another series of computational simulations and 4 sled tests were performed to fine-tune the optimal restraint design solutions.

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.

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.

A comparison of the NHTSA advanced dummy and the Hybrid III is presented in this paper based on their performance in repeated sled tests under 3 different restraint systems. The restraint systems considered are: the airbag alone, the 3-point belt alone, and a combined use of the airbag and the 3-point belt. Various time-histories pertaining to accelerations, angular velocities, deflections and forces have been compared between the two dummies in order to study their repeatability. The Hybrid III appears to be more repeatable than the NHTSA advanced dummy in its response in one case, that of restraint with the 3-point belt alone. The response of the NHTSA advanced dummy in other two restraint modes, the airbag alone and the combination of 3-point belt and airbag, appears to be no less repeatable than that of Hybrid III in this series of tests.

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 THOR's 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 results of biomechanical testing of the WorldSID prototype dummy are presented in this paper. The WorldSID dummy is a new, advanced Worldwide Side Impact Dummy that has the anthropometry of a mid-sized adult male. The first prototype of this dummy has been evaluated by the WorldSID Task Group against previously established corridors for its critical body regions. The response corridors are defined in the International Organization of Standardization (ISO) Technical Report 9790. The prototype is the first version of the WorldSID dummy to be built and tested. This dummy has been subjected to a rigorous program of testing to evaluate, first and foremost its biofidelity, but also its repeatability. Following this initial evaluation, any required modifications will be incorporated into a pre-production version of the WorldSID dummy so that it rates “good” to “excellent” on the ISO dummy biofidelity scale – a rating exceeding that of all current side impact dummies.

This technical paper presents the results from tests conducted with the ES-2re, a version of the ES-2 side impact dummy that was modified by the National Highway Traffic Safety Administration (NHTSA) to improve its performance in crash tests. Through the series of biofidelity tests conducted on the ES-2re, described in International Standards Organization (ISO) Technical Report (TR)9790 (1999), the OSRP observed a final overall biofidelity ranking of 4.1 for the ES-2re, which corresponds to an ISO classification of “marginal.” The biofidelity of the ES-2re is compared to that of the ES-2 and the WorldSID. Repeatability was also evaluated on the ES-2re based on the biofidelity test data. Additional pendulum tests were performed to assess the response of the dummy in oblique loading conditions, and results indicate that oblique loading from the front leads to significantly reduced rib deflections.

The purpose of this paper is to compare the biofidelity rating schemes of ISO/TR9790 and the NHTSA Bio Rank System. This paper describes the development of new impact response corridors being proposed for ISO/TR9790 from the results of a recent series of side-impact sled tests. The response data were analyzed by methods consistent with ISO/TR9790, including normalization by impulse-momentum analysis and the elimination of subjects that sustained six or more rib fractures. Unlike ISO/TR9790, this paper proposes the elimination of the data from tests in which the timing and the sequence of loading of the individual impact plates were inconsistent compared to other tests conducted with the same impact wall configuration.

This technical paper presents the results of biomechanical testing conducted on the ES-2 dummy by the Occupant Safety Research Partnership and Transport Canada. The ES-2 is a production dummy, based on the EuroSID-1 dummy, that was modified to further improve testing capabilities as recommended by users of the EuroSID-1 dummy. Biomechanical response data were obtained by completing a series of drop, pendulum, and sled tests that are outlined in the International Organization of Standardization Technical Report 9790 that describes biofidelity requirements for the midsize adult male side impact dummy. A few of the biofidelity tests were conducted on both sides of the dummy to evaluate the symmetry of its responses. Full vehicle crash tests were conducted to verify if the changes in the EuroSID-1, resulting in the ES-2 design, did improve the dummy's testing capability. In addition to the biofidelity testing, the ES-2 dummy repeatability, reproducibility and durability are discussed.