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NHTSA estimates that more than half of the lives saved (168,524) in car crashes between 1960 and 2002 were due to the use of seat belts. Nevertheless, while seat belts are vital to occupant crash protection, safety researchers continue efforts to further enhance the capability of seat belts in reducing injury and fatality risk in automotive crashes. Examples of seat belt design concepts that have been investigated by researchers include inflatable, 4-point, and reverse geometry seat belts. In 2011, Ford Motor Company introduced the first rear seat inflatable seat belts into production vehicles. A series of tests with child and small female-sized Anthropomorphic Test Devices (ATD) and small, elderly female Post Mortem Human Subjects (PMHS) was performed to evaluate interactions of prototype inflatable seat belts with the chest, upper torso, head and neck of children and small occupants, from infants to young adolescents.

This study evaluated the biomechanical performance of a rear-seat inflatable seatbelt system and compared it to that of a 3-point seatbelt system, which has a long history of good real-world performance. Frontal-impact sled tests were conducted with Hybrid III anthropomorphic test devices (ATDs) and with post mortem human subjects (PMHS) using both restraint systems and a generic rear-seat configuration. Results from these tests demonstrated: a) reduction in forward head excursion with the inflatable seatbelt system when compared to that of a 3-point seatbelt and; b) a reduction in ATD and PMHS peak chest deflections and the number of PMHS rib fractures with the inflatable seatbelt system and c) a reduction in PMHS cervical-spine injuries, due to the interaction of the chin with the inflated shoulder belt. These results suggest that an inflatable seatbelt system will offer additional benefits to some occupants in the rear seats.

The biomechanical behavior of a harness style 4-point seat belt system in farside impacts was investigated through dummy and post mortem human subject tests. Specifically, this study was conducted to evaluate the effect of the inboard shoulder belt portion of a 4-point seat belt on the risk of vertebral and soft-tissue neck injuries during simulated farside impacts. Two series of sled tests simulating farside impacts were completed with crash dummies of different sizes, masses and designs to determine the forces and moments on the neck associated with loading of the shoulder belt. The tests were also performed to help determine the appropriate dummy to use in further testing. The BioSID and SID-IIs reasonably simulated the expected kinematics response and appeared to be reasonable dummies to use for further testing. Analysis also showed that dummy injury measures were lower than injury assessment reference values used in development of side impact airbags.

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 biomechanical behavior of 4-point seat belt systems was investigated through MADYMO modeling, dummy tests and post mortem human subject tests. This study was conducted to assess the effect of 4-point seat belts on the risk of thoracic injury in frontal impacts, to evaluate the ability to prevent submarining under the lap belt using 4-point seat belts, and to examine whether 4-point belts may induce injuries not typically observed with 3-point seat belts. The performance of two types of 4-point seat belts was compared with that of a pretensioned, load-limited, 3-point seat belt. A 3-point belt with an extra shoulder belt that “crisscrossed” the chest (X4) appeared to add constraint to the torso and increased chest deflection and injury risk. Harness style shoulder belts (V4) loaded the body in a different biomechanical manner than 3-point and X4 belts.

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.

In 1998, Rouhana et al. described development of a new device, called the IR-TRACC (InfraRed - Telescoping Rod for Assessment of Chest Compression). In its original concept, the IR-TRACC uses two infrared LEDs inside of a telescoping rod to measure deflection. One LED serves as a light transmitter and the other as a light receiver. The output from the receiver LED is converted to a linear function of chest compression using an analog circuit. Tests have been performed with IR-TRACC units at various labs around the world since 1998. A first-generation IR-TRACC system was retrofit into a Q3 dummy by TNO. Similarly, a mid sized male Hybrid III dummy thorax and a small female Hybrid III dummy thorax have been designed by First Technology Safety Systems (FTSS) such that each contains 4 second-generation IR-TRACC units. The second-generation IR-TRACC is the result of continued development by FTSS, especially in the areas of the analysis circuit, manufacturing and calibration methods.

The objective of this work was to develop a reusable, rate-sensitive dummy abdomen with abdominal injury assessment capability. The primary goal for the abdomen developed was to have good biofidelity in a variety of loading situations that might be encountered in an automotive collision. This paper presents a review of previous designs for crash dummy abdomens, a description of the development of the new abdomen, results of testing with the new abdomen and instrumentation, and suggestions for future work. The biomechanical response targets for the new abdomen were determined from tests of the mid abdomen done in a companion biomechanical study. The response of the abdominal insert is an aggregate response of the dummy’s entire abdominal area and does not address differences in upper versus lower abdominal response, solid versus hollow organs, or organ position or mobility.

This study continued the biomechanical investigations of forearm fractures caused by direct loading of steering-wheel airbags during the early stages of deployment. Twenty-four static deployments of driver airbags were conducted into the forearms of unembalmed whole cadavers using a range of airbags, including airbags that are depowered as allowed by the new federal requirements for frontal impact testing. In general, the depowered airbags showed a reduction in incidence and severity of forearm fractures compared to the pre-depowered airbags tested. Data from these twenty-four tests were combined with results from previous studies to develop a refined empirical model for fracture occurrence based on Average Distal Forearm Speed (ADFS), and a revised value for fifty-percent probability of forearm-bone fracture of 10.5 m/s. Bone mineral content, which is directly related to forearm tolerance, was found to be linearly related to arm mass.