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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.

A dynamic rollover test system (DRoTS) capable of simulating rollover crashes in a laboratory was designed for research use at the University of Virginia. The goal of the current study is to describe the system's capabilities and specifications as well as to explore the limitations of the system's ability to simulate rollover crashes. The test apparatus was designed to permit simulation of a single roof-to-ground interaction of a rollover crash with the potential to be modified for evaluation of pre-roof contact occupant motion. Special considerations were made to permit testing of both dummies and post-mortem human surrogates in both production vehicles and a parametric test buck. DRoTS permits vertical translation, pitch, and roll of the test vehicle while constraining longitudinal and lateral translations and yaw. The study details the ranges of test parameters capable with the DRoTS and evaluates the limitations of the system relative to rollover crash conditions.

This investigation explored THOR's force-deflection response to upper abdomen/lower ribcage steering wheel rim impacts in comparison to the Hybrid III and cadaver test subjects. The stationary subjects were impacted by a ballasted surrogate wheel propelled at 4 m/s, a test condition designed to approximate the upper abdomen impacting a steering wheel rim in a frontal crash. Both the standard THOR and the Hybrid III crash dummies were substantially stiffer than the cadavers. Removing THOR's torso skin and foam from the upper abdomen and replacing the standard Hybrid III abdomen with a prototype gel-filled unit produced force-deflection results that were more similar to the cadavers. THOR offers advantages over the Hybrid III because of its ability to measure abdominal deflection. THOR, with modification, would be a useful instrument with which to assess the crashworthiness of steering assemblies and restraint systems in frontal crashes.

This paper discusses struck-side occupant thoracic response to side-impact loading and the requirements of a sled system capable of reproducing the relevant motions of a laterally impacted vehicle. A simplified viscoelastic representation of a thorax is used to evaluate the effect of the door velocity-time profile on injury criteria and on the internal stress state of the thorax. Simulations using a prescribed door velocity-time profile (punch impact) are contrasted against simulations using a constant-velocity impact (Heidelberg-type impact). It is found that the stress distribution and magnitude within the thorax, in addition to the maximum thorax compression and viscous response, depend not only on the door-occupant closing velocity, but also on the shape of the door velocity-time profile throughout the time of contact with the occupant. A sled system capable of properly reproducing side-impact door and seat motion is described.

This paper presents an analysis of the displacement measurement of the Hybrid III 50th percentile male dummy chest in quasistatic and dynamic loading environments. In this dummy, the sternal chest deformation is typically characterized using a sliding chest potentiometer, originally designed to measure inward deflection in the central axis of the dummy chest. Loading environments that include other modes of deformation, such as lateral translations or rotations, can create a displacement vector that is not aligned with this sensitive axis. To demonstrate this, the dummy chest was loaded quasistatically and dynamically in a series of tests. A string potentiometer array, with the capability to monitor additional deflection modes, was used to supplement the measurement of the chest slider.

This paper presents a computational study of the effects of three parameters on the resulting thoracic injury criteria in side impacts. The parameters evaluated are a) door velocity-time (V-t) profile, b) door interior padding modulus, and c) initial door-to-occupant offset. Regardless of pad modulus, initial offset, or the criterion used to assess injury, higher peak door velocity is shown to correspond with more severe injury. Injury outcome is not, however, found to be sensitive to the door velocity at the time of first occupant contact. A larger initial offset generally is found to result in lower injury, even when the larger offset results in a higher door velocity at occupant contact, because the increased offset results in contact later in the door V-t profile - closer to the point at which the door velocity begins to decrease. Cases of contradictory injury criteria trends are identified, particularly in response to changes in the pad modulus.

Although filter class specifications have been defined for most anthropomorphic test devices, no recommendation exists for the instrumented upper extremity. A three-part study was performed to determine the best channel filter class (CFC) to use for the instrumented upper extremity. By analyzing frequency content of signals from accelerometers and load cells, filtering data through three of the four possible CFC's to compare effects on the signals, and performing an injury comparison between cadaver data and the filtered load cell data, CFC 600 was chosen and recommended as the optimum filter class to use for upper extremity testing.

Some rollover testing methodologies require specification of vehicle kinematic parameters including travel speed, vertical velocity, roll rate, and pitch angle, etc. at the initiation of vehicle to ground contact, which have been referred to as touchdown conditions. The complexity of the vehicle, as well as environmental and driving input characteristics make prediction of realistic touchdown conditions for rollover crashes, and moreover, identification of parameter sensitivities of these characteristics, is difficult and expensive without simulation tools. The goal of this study was to study the sensitivity of driver input on touchdown parameters and the risk of rollover in cases of steering-induced soil-tripped rollovers, which are the most prevalent type of rollover crashes. Knowing the range and variation of touchdown parameters and their sensitivities would help in picking realistic parameters for simulating controlled rollover tests.

This paper compares restrained Hybrid III and THOR thoracic kinematics and cadaver injury outcome in 30° oblique frontal and in full frontal sled tests. Peak shoulder belt tension, the primary source of chest loading, changed by less than four percent and peak chest resultant acceleration changed by less than 10% over the 30° range tested. Thoracic kinematics were likewise insensitive to the direction of the collision vector, though they were markedly different between the two dummies. Mid-sternal Hybrid III chest deflection, measured by the standard sternal potentiometer and by supplemental internal string potentiometers, was slightly lower (∼10%) in the oblique tests, but the oblique tests produced a negligible increase in lateral movement of the sternum. In an attempt to understand the biofidelity of these dummy responses, a series of 30-km/h human cadaver tests having several collision vectors (0°, 15°, 30°, 45°) was analyzed.

The goals of this study were to examine the dynamic force-deformation and kinematic response of a late model van subjected to an inverted drop test and to evaluate the accuracy of three-dimensional multi-point roof deformation measurements made by an optical system mounted inside the vehicle. The inverted drop test was performed using a dynamic rollover test system (Kerrigan et al., 2011 SAE) with an initial vehicle pitch of −5 degrees, a roll of +155 degrees and a vertical velocity of 2.7 m/s at initial contact. Measurements from the optical system, which was composed of two high speed imagers and a commercial optical processing software were compared to deformation measurements made by two sets of three string potentiometers. The optical and potentiometer measurements reported similar deformations: peak resultant deformations varied by 0.7 mm and 3 ms at the top of the A-pillar, and 1.7 mm and 2 ms at the top of the B-pillar.

The goal of this study is to present the methods employed and results obtained during the first six tests performed with a new dynamic rollover test system. The tests were performed to develop and refine test methodology and instrumentation methods, examine the potential for variation in test parameters, evaluate how accurately actual touchdown test parameters could be specified, and identify problems or limitations of the test fixture. Five vehicles ranging in size and inertia from a 2011 Toyota Yaris (1174 kg, 379 kg m₂) to a 2002 Ford Explorer (2408 kg, 800 kg m₂) were tested. Vehicle kinematic parameters at the instant of vehicle-to-road contact varied across the tests: roll rates of 211-268 deg/s, roll angles of 133-199 deg, pitch angles of -12 deg to 0 deg, vertical impact velocities of 1.7 to 2.7 m/s, and road velocities of 3.0-8.8 m/s.

Given the quantity and severity of head injuries to pedestrians in vehicle-to-pedestrian collisions, human pedestrian finite element models and pedestrian dummies must possess a biofidelic head/neck response to accurately reproduce head-strike kinematics and kinetics. Full-scale pedestrian impact experiments were performed on post-mortem human surrogates (PMHS) using a mid-sized sport utility vehicle and a small sedan. Kinematics of the head and torso were obtained with a six-degree-of-freedom (6DOF) cube, which contained three orthogonally mounted linear accelerometers and three angular rate sensors. The goal of the current study was to present a methodology for analyzing the data obtained from the sensors on each cube, and to use the kinematics data to calculate spatial trajectories, as well as linear velocities and angular accelerations of the head and T1 vertebra.

Previous studies utilizing the Polar-II pedestrian dummy have suggested the need for a more biofidelic pelvis design in order to improve the overall dummy response kinematics. The current Polar-II dummy pelvis is a rigid steel structure. A preliminary version of a modified deformable pelvis equipped with sensors for measuring internal deflection and load has been designed. The goal of this study was to assess the biofidelity of these two pelves in full-scale tests with the Polar-II dummy that mimic lateral pelvic impact tests on PMHS (post-mortem human subjects) reported in the literature. The force - time, deflection - time, and force - deflection histories were compared to new PMHS response corridors determined using a normalization technique. In all tests with both pelves, the initial response (i.e., the first 3 ms to 5 ms following initial dummy - impactor contact) appeared to be totally determined by the mechanical behavior of the flesh.

Current crash dummy biofidelity standards include the estimated effects of tensing the muscles of the thorax. This study reviewed the decision to incorporate muscle tensing by examining relevant past studies and by using an existing mathematical model of thoracic impacts. The study finds evidence that muscle tensing effects are less pronounced than implied by the biofidelity standard response corridors, that the response corridors were improperly modified to include tensing effects, and that tensing of other body regions, such as extremity bracing, may have a much greater effect on the response and injury potential than tensing of only the thoracic musculature. Based on these findings, it is recommended that muscle tensing should be eliminated from thoracic biofidelity requirements until there is sufficient information regarding multi-region muscle tensing response and the capability to incorporate this new data into a crash dummy.

The major car and crash related risk factors for Whiplash Associated Disorders (WAD) 1-3 long-term neck injuries in rear-end crashes are the shape of the crash pulse, the seat-force characteristics and the head restraint position. However, the specific roles of these factors are not yet fully understood, which makes it difficult to find adequate countermeasures and to design protective car seats. In order to study these issues, a mathematical MADYMO model of the first version of the Biofidelic Rear Impact Dummy (BioRID I) has previously been developed. In addition, a neck injury criterion, NICmax, has been proposed and evaluated by means of dummy, human and rear-end impact simulations. In this paper the MADYMO BioRID I and four car seats ranked differently according to a disability ranking list are used to study the influence of crash pulse, seat-force characteristics, and head restraint position on the NICmax in rear-end crashes.

Steering control devices are used by people who have difficulty gripping the steering wheel. These devices have projections that may extend up to 14 cm toward the occupant. Testing indicated that contact with certain larger steering control devices with tall rigid projections could severely injure a driver in a frontal collision. In order to reduce this injury risk, an alternative, less injurious design was developed and tested. This design, which included replacing unyielding aluminum projections with compliant plastic ones, produced significantly lower peak contact pressure and less damage to the chest of a cadaver test subject, while maintaining the strength necessary to be useful.

Some rollover test methods, which impose a touchdown condition on a test vehicle, have been developed to study vehicle crashworthiness and occupant protection in rollover crashes. In ground-tripped rollover crashes, speed, steering maneuver, braking, vehicle inertial and geometric properties, topographical and road design characteristics, and soil type can all affect vehicle touchdown conditions. It is presumed that while there may be numerous possible combinations of kinematic metrics (velocity components and orientation) at touchdown, there are also numerous combinations of metrics that are not likely to occur in rollover crashes. To determine a realistic set of touchdown conditions to be used in a vehicle rollover crash test, a lateral deceleration sled-based non-destructive rollover initiation test system (RITS) with a fully programmable deceleration pulse is in development.

The goal of this study was to evaluate the biofidelity of the three computational surrogates (GHBMC model, WorldSID model, and the FTSS ES-2re model) under the side impact rigid wall sled test condition. The responses of the three computational surrogates were compared to those of post mortem human surrogate (PMHS) and objectively evaluated using the correlation and analysis (CORA) rating method. Among the three computational surrogates, the GHBMC model showed the best biofidelity based on the CORA rating score (GHBMC =0.65, WorldSID =0.57, FTSS ES-2re =0.58). In general, the response of the pelvis of all the models showed a good correlation with the PMHS response, while the response of the shoulder and the lower extremity did not. In terms of fracture prediction, the GHBMC model overestimated bone fracture.

Frontal impacts with reclined occupants are rare but severe, and they are anticipated to become more common with the introduction of vehicles with automated driving capabilities. Computational and physical human surrogates are needed to design and evaluate injury countermeasures for reclined occupants, but the validity of such surrogates in a reclined posture is unknown. Experiments with post-mortem human subjects (PMHS) in a recline posture are needed both to define biofidelity targets for other surrogates and to describe the biomechanical response of reclined occupants in restrained frontal impacts. The goal of this study was to evaluate the kinematic and injury response of reclined PMHS in 30 g, 50 km/h frontal sled tests. Five midsize adult male PMHS were tested. A simplified semi-rigid seat with an anti-submarining pan and a non-production three-point seatbelt (pre-tensioned, force-limited, seat-integrated) were used.

Forced dorsiflexion in frontal vehicle crashes is considered a common cause of injury to the ankle joint. Although a few studies have been published on the dynamic fracture tolerance of the ankle in dorsiflexion, this work reexamines the topic with increased statistical power, adds an evaluation of articular cartilage injury, and utilizes methods to detect the true time of fracture. The objective of this study was to measure the response and injury tolerance of the human ankle in a loading condition similar to that found in a vehicle crash with toepan intrusion. A test fixture was constructed to apply forefoot impacts to twenty cadaveric lower limbs, that were anatomically intact distal to the femur mid-diaphysis. Specimen instrumentation included implanted tibial and fibular load cells, accelerometers, angular rate sensors, and an acoustic sensor. Following the tests, specimens were radiographed and dissected to determine the extent of injury.