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Transfer or response equations are important as they provide relationships between the responses of different surrogates under matched, or nearly identical loading conditions. In the present study, transfer equations for different body regions were developed via mathematical modeling. Specifically, validated finite element models of the age-dependent Ford human body models (FHBM) and the mid-sized male Hybrid III (HIII50) were used to generate a set of matched cases (i.e., 192 frontal sled impact cases involving different restraints, impact speeds, severities, and FHBM age). For each impact, two restraint systems were evaluated: a standard three-point belt with and without a single-stage inflator airbag. Regression analyses were subsequently performed on the resulting FHBM- and HIII50-based responses. This approach was used to develop transfer equations for seven body regions: the head, neck, chest, pelvis, femur, tibia, and foot.

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.

Injury to the far side occupant has been demonstrated as a significant portion of the total trauma in side impacts. The objective of the study was to determine the response of PMHS in far side impact configurations, with and without generic countermeasures, and compare responses to the WorldSID and THOR dummies. A far side impact buck was designed for a sled test system that included a center console and three-point belt system. The buck allowed for additional options of generic countermeasures including shoulder or thorax plates or an inboard shoulder belt. The entire buck could be mounted on the sled in either a 90-degree (3-o'clock PDOF) or a 60-degree (2-o'clock PDOF) orientation. A total of 18 tests on six PMHS were done to characterize the far side impact environment at both low (11 km/h) and high (30 km/h) velocities. WorldSID and THOR-NT tests were completed in the same configurations to conduct matched-pair comparisons.

This study applies a detailed finite element model of the human body to simulate occupant knee impacts experienced in vehicular frontal crashes. The human body model includes detailed anatomical features of the head, neck, chest, thoracic and lumbar spine, abdomen, and lower and upper extremities. The material properties used in the model for each anatomic part of the human body were obtained from test data reported in the literature. The total human body model used in the current study has been previously validated in frontal and side impacts. Several cadaver knee impact tests representing occupants in a frontal impact condition were simulated using the previously validated human body model. Model impact responses in terms of force-time and acceleration-time histories were compared with test results. In addition, stress distributions of the patella, femur, and pelvis were reported for the simulated test conditions.

This paper presents the results of biomechanical testing of the SID-IIs beta+-prototype dummy by the Occupant Safety Research Partnership. The purpose of this testing was to evaluate the dummy against its previously established biomechanical response corridors for its critical body regions. The response corridors were scaled from the 50th percentile adult male corridors defined in International Standards Organization Technical Report 9790 to corridors for a 5th percentile adult female, using established International Standards Organization procedures. Tests were performed for the head, neck, shoulder, thorax, abdomen and pelvis regions of the dummy. Testing included drop tests, pendulum impacts and sled tests. The biofidelity of the SID-IIs beta+-prototype was calculated using a weighted biomechanical test response procedure developed by the International Standards Organization.

Airbag deployments are associated with loud noise of short duration, called impulse noise. Research performed in the late 1960's and early 1970's established several criteria for assessment of the risk of impulse noise-induced hearing loss for military weapons and general exposures. These criteria were modified for airbag noise in the early 1970's, but field accident statistics and experimental results with human volunteers exposed to airbags do not seem to agree with the criteria. More recent research on impulse noise from weapons firing, in particular that of Price & Kalb of the US Army Research Laboratory, has led to development of a mathematical model of the ear. This model incorporates transfer functions which alter the incident sound pressure through various parts of the ear. It also calculates a function, called the “hazard”, that is a measure of mechanical fatigue of the hair cells in the inner ear.

Two-dimensional film analysis was conducted to study the kinematics of the head and neck of 17 restrained human volunteers in 24 frontal impacts for acceleration levels from 6g to 15g. The trajectory of the head center of gravity relative to upper torso reference points and the rotation of head and neck relative to the lower torso during the forward motion phase were of particular interest. The purpose of the study was to analyze the head-neck kinematics in the mid-sagittal plane for a variety of human volunteer frontal sled tests from different laboratories using a common analysis method for all tests, and to define a common response corridor for the trajectory of the head center-of-gravity from those tests.

Injuries to the thorax and abdomen comprise a significant percentage of all occupant injuries in motor vehicle accidents. While the percentage of internal chest injuries is reduced for restrained front-seat occupants in frontal crashes, serious skeletal chest injuries and abdominal injuries can still result from interaction with steering wheels and restraint systems. This paper describes the design and performance of prototype components for the chest, abdomen, spine, and shoulders of the Hybrid III dummy that are under development to improve the capability of the Hybrid III frontal crash dummy with regard to restraint-system interaction and injury-sensing capability.

The SAE Recommended Practice for measuring impulse noise from airbags, SAE J247, “Instrumentation for Measuring Acoustic Impulses within Vehicles”, was first published in 1971 and last affirmed in 1987. Many advances have occurred in understanding and technology since that time. Work in the automotive industry to investigate the characteristics of noise from airbag deployments has shown that large components of low frequency noise can be present when an airbag deploys in a closed vehicle. Others have shown that this low frequency noise can have a protective effect on the ear. Likewise, work for many years at the US Army Research Lab has investigated the risk of hearing loss for a human subjected to an acoustic impulse. That research led to the creation and validation of a mathematical model of the human ear, called Auditory Hazard Assessment Algorithm - Human (AHAAH).

Seventeen left lateral impact experiments were performed using anesthetized swine to determine the biomechanics of injury production in this impact mode. Two series of eight animals were used and one animal served as a control. In the first series of experiments, rigid thoracic and pelvic loading surfaces were separated by an “interplate gap” of 20.3 cm (8”). In the second series of experiments, the interplate gap was filled by a rigid plate mounted flush with the thoracic and pelvic loading surfaces. Impact velocities ranged from 7.2 to 15.0 m/s (about 15 to 30 mph). Injury patterns for the liver, spleen, and rib cage were significantly different in the two series of experiments (level of significance > 90%). The causative factor responsible for the different injury outcomes was the interplate gap. The conclusion of this report is that loading-surface discontinuities can cause significant injury.

An understanding of stiffness characteristics of different body regions, such as thorax, abdomen and pelvis of ES-2re and SID-IIs dummies under controlled laboratory test conditions is essential for development of both compatible performance targets for countermeasures and occupant protection strategies to meet the recently updated FMVSS214, LINCAP and IIHS Dynamic Side Impact Test requirements. The primary purpose of this study is to determine the transfer functions between the ES-2re and SID-IIs dummies for different body regions under identical test conditions using flat rigid wall sled tests. The experimental set-up consists of a flat rigid wall with five instrumented load-wall plates aligned with dummy’s shoulder, thorax, abdomen, pelvis and femur/knee impacting a stationary dummy seated on a rigid low friction seat at a pre-determined velocity.

The main purpose of this study was to determine the impact responses of the different body regions (shoulder, thorax, abdomen and pelvis/leg) of the ES-2re and SID-IIs dummies using rigid wall impacts under different initial test conditions. The experimental set-up consisted of a flat rigid wall with five instrumented load-wall plates aligned with dummy’s shoulder, thorax, abdomen, pelvis and knee impacting a stationary dummy seated on a rigid seat at a pre-determined velocity. The relative location and orientation of the load-wall plates was adjusted relative to the body regions of the ES-2re and SID-IIs dummies respectively.

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 study was conducted to resolve discrepancies and fill in gaps in the biomechanical impact response of the human abdomen to frontal impact loading. Three types of abdominal loading were studied: rigid-bar impacts, seatbelt loading, and close-proximity (out-of-position) airbag deployments. Eleven rigid-bar free-back tests were performed into the mid and upper abdomens of unembalmed instrumented human cadavers using nominal impact speeds of 6 and 9 m/s. Seven fixed-back rigid-bar tests were also conducted at 3, 6, and 9 m/s using one cadaver to examine the effects of body mass, spinal flexion, and repeated testing. Load-penetration corridors were developed and compared to those previously established by other researchers. Six seatbelt tests were conducted using three cadavers and a peak-loading rate of 3 m/s. The seatbelt loading tests were designed to maximize belt/abdomen interaction and were not necessarily representative of real-world crashes.

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.

There has been recent progress over the past 10 years in research comparing 6-year-old thoracic and abdominal response of pediatric volunteers, pediatric post mortem human subjects (PMHS), animal surrogates, and 6-year-old ATDs. Although progress has been made to guide scaling laws of adult to pediatric thorax and abdomen data for use in ATD design and development of finite element models, further effort is needed, particularly with respect to lateral impacts. The objective of the current study was to use the impact response data of age equivalent swine from Yaek et al. (2018) to assess the validity of scaling laws used to develop lateral impact response corridors from adult porcine surrogate equivalents (PSE) to the 3-year-old, 6-year-old, and 10-year-old for the thorax and abdominal body regions.

Analysis and validation of current scaling relationships and existing response corridors using animal surrogate test data is valuable, and may lead to the development of new or improved scaling relationships. For this reason, lateral pendulum impact testing of appropriate size cadaveric porcine surrogates of human 3-year-old, 6-year-old, 10-year-old, and 50th percentile male age equivalence, were performed at the thorax and abdomen body regions to compare swine test data to already established human lateral impact response corridors scaled from the 50th percentile human adult male to the pediatric level to establish viability of current scaling laws. Appropriate Porcine Surrogate Equivalents PSE for the human 3-year-old, 6-year-old, 10-year-old, and 50th percentile male, based on whole body mass, were established. A series of lateral impact thorax and abdomen pendulum testing was performed based on previously established scaled lateral impact assessment test protocols.

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.

Frontal airbag interaction with the head and neck of the Hybrid III family of dummies may involve a nonbiofidelic interaction. Researchers have found that the deploying airbag may become entrapped in the hollow cavity behind the dummy chin. This study evaluated a prototype neck shield design, the Flap Neck Shield, for biofidelic response and the ability to prevent airbag entrapment in the chin/jaw cavity. Neck pendulum calibration tests were conducted for biofidelity evaluation. Static and dynamic airbag deployments were conducted to evaluate neck shield performance. Tests showed that the Flap Neck Shield behaved in a biofidelic manner with neck loads and head motion within established biofidelic limits. The Flap Neck Shield did not alter the neck loads during static or dynamic airbag interactions, but it did consistently prevent the airbag from penetrating the chin/jaw cavity.

This paper describes the injuries generated during dynamic belt loading to a porcine model of the 6-year-old human abdomen, and correlates injury outcomes with measurable parameters. The test fixture produced transverse, dynamic belt loading on the abdomen of 47 immediately post-mortem juvenile swine at two locations (upper/lower), with penetration magnitudes ranging from 23% – 65% of the undeformed abdominal depth, with and without muscle tensing, and over a belt penetration rate range of 2.9 m/s – 7.8 m/s. All thoracoabdominal injuries were documented in detail and then coded according to the Abbreviated Injury Scale (AIS). Observed injuries ranged from AIS 1 to AIS 4. The injury distribution matched well the pattern of injuries observed in a large sample of children exposed to seatbelt loading in the field, with most of the injuries in the lower abdomen.