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To serve as tools for assessing injury risk, the biofidelity of whole-body pedestrian impact dummies should be validated against reference data from full-scale pedestrian impact tests. To facilitate such evaluations, a simplified generic vehicle-buck has been recently developed that is designed to have characteristics representative of a generic small sedan. Three 40 km/h pedestrian-impact tests have been performed, wherein Post Mortem Human Surrogates (PMHS) were struck laterally in a mid-gait stance by the buck. Corridors for select trajectory measures derived from these tests have been published previously. The goal of this study is to act as a companion dataset to that study, describing the head velocities, body region accelerations (head, spine, pelvis, lower extremities), angular velocities, and buck interaction forces, and injuries observed during those tests.

Drop testing of the Hybrid III dummy head was conducted to determine variations in Head Injury Criteria values with the point of head impact, and how the variations relate to actual head injuries. Head drop tests indicated that impacts to the temple and lower forehead posed the greatest injury risks. Moreover, the application of chamois or chalk over the head, a common practice among safety researchers to detect racial lacerations and head contacts, was found to significantly lower Head Injury Criteria values for all impact locations.

Sixty-three simulated frontal impacts using cadaveric specimens were performed to examine and quantify the performance of various contemporary automotive restraint systems. Test specimens were instrumented with accelerometers and chest bands to characterize their mechanical responses during the impact. The resulting thoracic injury severity was determined using detailed autopsy and was classified using the Abbreviated Injury Scale. The ability of various mechanical parameters and combinations of parameters to assess the observed injury severities was examined and resulted in the observation that belt restraint systems generally had higher injury rates than air bag restraint systems for the same level of mechanical responses. To provide better injury evaluations from observed mechanical parameters without prior knowledge of what restraint system was being used, a dichotomous process was developed.

The likelihood of a front seat occupant sustaining a femoral shaft fracture in a frontal crash has traditionally been assessed by an injury criterion relying solely on the axial force in the femur. However, recently published analyses of real-world data indicate that femoral shaft fracture occurs at axial loads levels below those found experimentally. One hypothesis attempting to explain this discrepancy suggests that femoral shaft fracture tends to occur as a result of combined axial compression and applied bending. The current study aims to evaluate this hypothesis by investigating how these two loading components interact. Femoral shafts harvested from human cadavers were loaded to failure in axial compression, sagittal plane bending, and combined axial compression and sagittal plane bending.

Though rotation is thought to be the most common mechanism of foot and ankle injury in both automobile crashes and in everyday life, axial impact loading is considered responsible for most severe lower extremity injuries. In this study, dynamic axial impact tests were conducted on 92 isolated human lower limbs. The test apparatus delivered the impact via a pendulum-driven plate which intruded longitudinally to simulate the motion of the toepan in an automobile crash. Magneto-hydrodynamic (MHD) angular rate sensors fixed to the limbs measured ankle rotations during the impact event. Malleolar or fibula fractures, which are commonly considered to be caused by excessive ankle rotation, were present in 38% (12 out of 32) of the injured specimens. Ankle rotations in these tests were always within 10° of neutral at the time of peak axial load and seldom exceeded failure boundaries reported in the literature at any point during the impact event.

The purpose of this study is to evaluate the hard tissue injury -predictive value of various thoracic injury criteria when the restraint conditions are varied. Ten right-front passenger human cadaver sled tests are presented, all of which were performed at 48 km/h with nominally identical sled deceleration pulses. Restraint conditions evaluated are 1) force-limiting belt and depowered airbag (4 tests), 2) non-depowered airbag with no torso belt (3 tests), and 3) standard belt and depowered airbag (3 tests). Externally measured chest compression is shown to correspond well with the pre sence of hard tissue injury, regardless of restraint condition, and rib fracture onset is found to occur at approximately 25% chest compression. Peak acceleration and the average spinal acceleration measured at the first and eighth or ninth thoracic vertebrae are shown to be unrelated to the presence of injury, though clear variations in peaks and time histories among restraint conditions can be seen.

Forced inversion or eversion of the foot is considered a common mechanism of ankle injury in vehicle crashes. The objective of this study was to model empirically the injury tolerance of the human ankle/subtalar joint to dynamic inversion and eversion under three different loading conditions: neutral flexion with no axial preload, neutral flexion with 2 kN axial preload, and 30° of dorsiflexion with 2 kN axial preload. 44 tests were conducted on cadaveric lower limbs, with injury occurring in 30 specimens. Common injuries included malleolar fractures, osteochondral fractures of the talus, fractures of the lateral process of the talus, and collateral ligament tears, depending on the loading configuration. The time of injury was determined either by the peak ankle moment or by a sudden drop in ankle moment that was accompanied by a burst of acoustic emission. Characteristic moment-angle curves to injury were generated for each loading configuration.

Axial loading of the foot/ankle complex is an important injury mechanism in vehicular trauma that is responsible for severe injuries such as calcaneal and tibia pilon fractures. Axial loading may be applied to the leg externally, by the toepan and/or pedals, as well as internally, by active muscle tension applied through the Achilles tendon during pre-impact bracing. In order to evaluate the effect of active muscle tension on the injury tolerance of the foot/ankle complex, blunt axial impact tests were performed on 44 isolated lower legs with and without experimentally simulated Achilles tension. The primary fracture mode was calcaneal fracture in both groups, but tibia pilon fractures occurred more frequently with the addition of Achilles tension. Acoustic emission demonstrated that fracture initiated at the time of peak local axial force.

This paper presents a study characterizing the interaction between a small female upper extremity and a deploying side air bag. The results are based on 12 tests with small female cadavers, and 15 tests with the instrumented SAE 5th percentile female upper extremity attached to the 5th percentile Hybrid III female dummy. The upper extremity was loaded by a deploying seat mounted thoracic side air bag in a static test environment. Three types of inflators were used that varied in peak pressure and pressure onset rate. Three upper extremity positions where chosen that maximized loading to the humerus and elbow joint. Upper extremity instrumentation for both the cadaver and dummy tests included accelerometers and angular rate sensors on the forearm, humerus, and upper spine. Additional instrumentation on the cadavers included strain gage rosettes on the anterior and posterior humerus.

The objectives of this study were to evaluate and compare the responses, repeatability, and durability of the Thor-Lx/HIIIr and Hybrid III/Denton lower extremities in frontal sled tests. Effectiveness of the two limb types was studied by evaluating responses in different test configurations using existing and proposed Injury Assessment Reference Values (IARVs) for both leg designs. Hybrid III or Thor-Lx legs were attached to the distal femurs of a 50th percentile male Hybrid III dummy, which was subjected to three series of 56 km/h frontal sled tests with and without toepan intrusion. Due to the design differences, many of the absolute response values were different between the Hybrid III and Thor-Lx legs. The expanded measurement capabilities, modified geometry and refined responses of the Thor-Lx limbs provide a more thorough and conservative judgment of injury risk.

The University of Virginia is investigating the biomechanical response and the injury tolerance of the lower extremities. This paper presents the experimental and simulation work used to study the injury patterns and mechanisms of the ankle/foot complex. The simulation effort has developed a segmented lower limb and foot model for an occupant simulator program to study the interactions of the foot with intruding toepan and pedal components. The experimental procedures include static tests, pendulum impacts, and full-scale sled tests with the Advanced Anthropomorphic Test Device and human cadavers. In these tests, the response of the lower extremities is characterized with analogous dummy and cadaver instrumentation packages that include strain gauges, electrogoniometers, angular rate sensors, accelerometers, and load cells. An external apparatus is applied to the surrogate's lower extremities to simulate the effects of muscle tensing.

The response and risk of injury for occupants in frontal crashes are more severe when structural deformation occurs in the vehicle interior. To reproduce this impact environment in the laboratory, a sled system capable of producing structural intrusion in the footwell region has been developed. The system couples the hydraulic decelerator of the sled to actuator pistons attached to the toepan and floorpan structure of the buck. Characterization of the footwell intrusion event is based on developing a toepan pulse analogous to the acceleration pulse used to characterize sled and vehicle decelerations. Preliminary sled tests with the system indicate that it is capable of simulating a complex sequence of toepan/floorpan translations and rotations.

Far-side kinematics and injury are influenced by the occupant environment. The goal of the present study was to evaluate in-vehicle human far-side kinematics, kinetics and injury and to assess the ability of the WorldSID to represent them. A series of tests with five Post-Mortem Human Subjects and the WorldSID were conducted in a vehicle-based sled test environment. The surrogates were subjected to a far-side pulse of 16.5 g in a 75-degree impact direction. The PMHS were instrumented with 6 degree-of-freedom sensors to the head, spine and pelvis, a chestband, strain gauge rosettes, a 3D tracking array mounted to the head and multiple single 3D tracking markers on the rest of the body. The WorldSID lateral head excursion was consistent with the PMHS. However, forward head excursion did not follow a PMHS-like trajectory after the point of maximum lateral excursion. All but one PMHS retained the shoulder belt on the shoulder during the entire test.

Rollover crashes are a serious public health problem in United States, with one third of traffic fatalities occurring in crashes where rollover occurred. While it has been shown that occupant kinematics affect the injury risk in rollover crashes, no anthropomorphic test device (ATD) has yet demonstrated kinematic biofidelity in rollover crashes. Therefore, the primary goal of this study was to assess the kinematic response biofidelity of six ATDs (Hybrid III, Hybrid III Pedestrian, Hybrid III with Pedestrian Pelvis, WorldSID, Polar II and THOR) by comparing them to post mortem human surrogate (PMHS) kinematic response targets published concurrently; and the secondary goal was to evaluate and compare the kinematic response differences among these ATDs.

Crash test dummies rely on biomechanical data from cadaver studies to biofidelically reproduce loading and predict injury. Unfortunately, it is difficult to obtain equivalent measurements of leg loading in a dummy and a cadaver, particularly for bending moments. A methodology is presented here to implant load cells in the tibia and fibula while minimally altering the functional anatomy of the two bones. The location and orientation of the load cells can be measured in all six degrees of freedom from post-test radiographs. Equations are given to transform tibial and fibular load cell measurements from a cadaver or dummy to a common leg coordinate frame so that test data can be meaningfully compared.

This paper presents a load distribution-specific viscoelastic structural characterization of the Hybrid III 50th percentile male anthropomorphic test dummy thorax. The dummy is positioned supine on a high-speed material testing machine and ramp-and-hold tests are performed using a distributed load, a hub load, and a diagonal belt load applied to the anterior thorax of the dummy. The force-deflection response is shown to be linear viscoelastic for all loading conditions when the internal dummy instrumentation is used to measure chest deflection. When an externally measured displacement (i.e., a measurement that includes the superficial skin material) is used for the characterization, a quasilinear viscoelastic characterization is necessary. Linear and quasilinear viscoelastic model coefficients are presented for all three loading conditions.

Pediatric pedestrians are frequently involved in Pedestrian versus Motor Vehicle Collisions (PMVCs). While in recent years, the automotive industry has worked towards making cars less aggressive to pedestrians, the efforts have mainly focused on adult pedestrian safety. When they have included considerations for children, only head injuries have been evaluated. The development of automotive countermeasures that provide protection for both adult and pediatric pedestrians requires access to injury criteria for the entire body that specifically account for both the age-dependent tissue properties and the pedestrian's size. The objective of the present study is to derive lateral injury criteria for the upper and lower extremities that can be used in finite element and multi-body simulations of PMVCs involving the 6-year-old pedestrian (corresponding injury criteria for the head, neck, thorax, abdomen and pelvis are derived in part I of this study).

Pediatric pedestrians are frequently involved in Pedestrian versus Motor Vehicle Collisions (PMVCs). While in recent years, the automotive industry has worked towards making cars less aggressive to pedestrians, the efforts have mainly focused on adult pedestrian safety. When they have included considerations for children, only head injuries have been evaluated. The development of automotive counter-measures that provide protection for both adult and pediatric pedestrians requires access to injury criteria for the entire body that specifically account for both the age-dependent tissue properties and the pedestrian's size. The objective of the present study is to derive lateral injury criteria for the head, neck, thorax, abdomen and pelvis that can be used in finite element and multi-body simulations of PMVCs involving the 6-year-old pedestrian (corresponding injury criteria for the upper and lower extremities are derived in part II of this study).

This paper presents a parametric study that utilized the CVS/ATB multi-body simulation program to investigate the interaction of the hand and wrist with a door handgrip during side air bag loading. The goal was to quantify the relative severity of various hand and handgrip positions as a guide in the selection of a test matrix for laboratory testing. The air bag was represented as a multi-body system of ellipsoidal surfaces that were created to simulate a prototype seat-mounted thorax side air bag. All simulations were set in a similar static test environment as used in corresponding dummy and cadaver side air bag testing. The occupant mass and geometric properties were based on a 5th percentile female occupant in order to represent a high-risk segment of the adult population. The upper extremity model consisted of wrist and forearm rotations that were based on human volunteer data.

The purpose of this study was to develop a fracture tolerance for the elbow joint, or proximal ends of the ulna and radius, relative to the fracture risk under side-impact airbag loading. Forty experiments were performed on the elbow joints of small female cadavers. The energy source, a pneumatic impactor, was configured to apply compressive loads that match the onset rate, peak force, and momentum transfer of previously conducted side-impact airbag tests with small female subjects. Three initial orientations of the impact load angle relative to the longitudinal axis of the forearm were selected based on analysis of side-impact airbag tests with the instrumented dummy upper extremity. These included loading directions that are 0°, 20°, and 30° superior of the longitudinal axis of the forearm. Post-test necropsy revealed that 11 of the 40 tests resulted in chondral, osteochondral, or comminuted fractures of the proximal radial head or the distal trochlear notch.