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The SAE J826 H-point machine was designed to measure occupant accommodation dimensions relative to a loaded seat. It has become an intrinsic part of various crash dummy set up processes, but it has never had a formal calibration procedure. Whilst H-point location appears to be consistent from one device to another, the weight hanger locations show greater variability, and this can consequently affect the height and backset measurements of head restraints taken with a head restraint measuring device mounted upon the weight hangers. This paper describes the development of a calibration procedure and jig to measure the location of the weight hangers so that adjustments can be made if necessary. This procedure and calibration tool will enable more consistent seat evaluations, dummy set up, and consistently effective anti-whiplash seat designs.

Anthropometric test devices (ATDs) instrumented with potentiometers and accelerometers are used regularly to assess thoracic injury risk in side impact crash tests. Measurements from these sensors are compared with injury assessment reference values (IARVs) for lateral loading to establish the risk of injury for humans subjected to similar impacts. In crash tests, the deflections and deflection rates derived from these two types of sensors (potentiometers vs. accelerometers) have varying degrees of agreement. In some cases, differences can be relatively large. In the past, it was unclear whether the reason for the differences was off-axis loading that misaligned the accelerometers used in the calculation, an inherent inability of the potentiometer to capture high deflection rates under certain conditions, or some other phenomenon.

The Insurance Institute for Highway Safety installed a variety of infant, toddler, and booster restraints in vehicles subjected to high-speed frontal offset crash tests to assess the effects of severe crashes on the structural integrity of the restraints and their associated hardware (harnesses, buckles, clips, etc.). The child restraints were inspected before and after each test, and all damage was recorded. In some of the tests, forces and accelerations were recorded on the appropriate size child dummy properly secured in the child restraint. After a single severe crash, most restraints had sustained some damage, albeit minimal. Repeated tests indicated that these child restraints could withstand the forces of an additional crash with only minor additional damage. Dummy injury results suggest that current injury risk curves overstate the risk of neck injury to most properly restrained children.

The knee and ankle joint pivots of the Hybrid III dummy's leg are positioned in approximately the same orientation as the knee and ankle joint rotation centers of a human in a normal driving posture. However, the dummy's leg assembly is not simply a straight member between these two pivots. It is a zigzag-shaped solid link composed of one long straight section in the middle and short angled sections at either end, which form the pivots. The upper and lower tibia load cells are mounted on the straight middle section, making the upper tibia load cell location anterior to the line between the ankle and knee pivots and the lower tibia load cell location slightly posterior to the line between the pivots. Hence, an approximately vertical force on the foot can act along the line behind the upper tibia load cell and in front of the lower tibia load cell, creating bending moments.

This study, which is an extension of an earlier study, examined an additional 64 frontal crashes of airbag-equipped vehicles in the 1997-98 National Automotive Sampling System Crashworthiness Data System (NASS/CDS) in which the driver died. The principal cause of death in each case was determined based on an examination of the publicly available case materials, which primarily consisted of the crash narrative, the injury/source summary, and photographs of the crashed vehicle. Results were consistent with the earlier analyses of the 1990-96 NASS/CDS files. In the combined data set (1990-98), gross deformation of the occupant compartment was the leading cause (42 percent) of driver deaths in these 116 frontal crashes. The force of the deploying airbag (16 percent) and ejection from the vehicle (13 percent) also accounted for significant portions of the driver deaths in these frontal crashes. There continues to be little or no evidence that airbags deploy with too little energy.

A review of 39 driver fatalities in 1990-93 cars with air bags from the National Accident Sampling System indicated most of these fatalities were due to causes unrelated to frontal air bag performance. Two-thirds occurred in side-impact or rollover crashes, in which air bag effectiveness is limited; of 15 frontal crash fatalities, 6 died of causes unrelated to the frontal impact and 5 in cars with severe intrusion. The remaining four fatalities, three of whom were unbelted, were in moderate to high severity crashes which could have been survivable; however the deploying air bags, instead of protecting, probably contributed to the fatal injuries. A similar review of 12 fatalities of unbelted drivers in cars without air bags revealed 3 could have been prevented by air bags, but 4 were in crashes that could have put them in position to be injured by the air bag.

Data on deaths of car occupants during the calendar year 1975 were obtained from the National Highway Traffic Safety Administration's Fatal Accident Reporting System, and national vehicle registration counts were obtained from R. L. Polk National Profile as of July 1, 1975. Occupant deaths per 10,000 registered cars in the 1971 through 1974 model years were examined by vehicle size. Occupant death rates generally increase as car size decreases. The relationship between smaller cars and increased deaths is especially pronounced in frontal crashes, and in car into other vehicle crashes. Because of this, increased occupant crash protection in frontal crashes-such as provided by air bags and passive seat belts-could substantially reduce much of the disadvantage presently faced by occupants of small cars.

Using data from the National Automotive Sampling System/Crashworthiness Data System (NASS/CDS) for1995-96, this study updates previous analyses of driver fatalities in airbag-equipped vehicles in the NASS/CDS database for 1989-93 and 1989-94. A total of 59 cases of frontal crashes of airbag-equipped vehicles with driver fatalities were identified in these 8 years of NASS/CDS data, but in 9 cases the fatalities were not related to the impacts (e.g., fire, medical condition). Vehicle intrusion was the cause of the fatal injuries in 27 cases, and 7drivers died from injuries sustained when they were either partially or totally ejected from their vehicles. There was one case in which the airbag did not deploy, although the crash conditions indicated it should have. One driver died from contact with a nonintruding vehicle surface, and the causes of the fatal injuries in 5 cases were unknown.

After decades of focus on car designs that improve the crash protection of occupants in their own cars, some theorists have refocused their attention on vehicle aggressivity, or more generally, the compatibility of vehicles when they crash with each other. Real-world fatal crash data reveal important issues of compatibility related to the broad mix of types and sizes of vehicles in the fleet. However, these data also show that incompatibility among passenger vehicles has accounted for only a small proportion of crash fatalities on U.S. roads and that modifications of the more aggressive vehicles, though appropriate and necessary, will have relatively small effects. Interventions to curtail the development and sale of the largest and heaviest passenger vehicles would be ineffective.

In 2012, the Insurance Institute for Highway Safety (IIHS) began a 64 km/h small overlap frontal crash test consumer information test program. Thirteen automakers already have redesigned models to improve test performance. One or more distinct strategies are evident in these redesigns: reinforcement of the occupant compartment, use of energy-absorbing fender structures, and the addition of engagement structures to induce vehicle lateral translation. Each strategy influences vehicle kinematics, posing additional challenges for the restraint systems. The objective of this two-part study was to examine how vehicles were modified to improve small overlap test performance and then to examine how these modifications affect dummy response and restraint system performance. Among eight models tested before and after design changes, occupant compartment intrusion reductions ranged from 6 cm to 45 cm, with the highest reductions observed in models with the largest number of modifications.

A BioRID (biofidelic rear impact dummy) representing a 50th percentile adult male was seated in the front passenger seat of six new vehicle models in a series of low-speed crash tests. The neck injury criterion (NIC) and other dummy responses that may indicate whiplash injury risk were recorded. Both front-into- rear and rear-into-barrier tests with an average velocity change of 11 km/h were conducted. Head restraints were tested in both adjusted (up) and unadjusted (down) positions. Damage to all models was minor, and longitudinal vehicle accelerations were low (less than 7 g). Neck extension angles and bending moments were much less than injury assessment reference values (IARV) (80 degrees and 57 Nm, respectively), indicating low risk of hyperextension injuries. Neck tension and transverse forces also were less than IARVs used to indicate the risk of more serious neck injuries.

The Insurance Institute for Highway Safety (IIHS) is investigating small overlap crash test procedures for a possible consumer information program. Analysis of real-world small overlap crashes found a strong relationship between serious head and chest injuries and occupant compartment intrusion. The main sources of serious head injuries were from the A-pillar, dash panel, or door structure, suggesting head trajectories forward and outboard possibly bypassing the airbag. Chest injuries mainly were from steering wheel intrusion and seat belt loading. In developing this program, two test dummies were evaluated for predicting occupant injury risk: midsize male Hybrid III and THOR. In the collinear small overlap crash tests conducted here, results from the two dummies were similar. Both predicted a low risk of injury to the head and chest and sometimes a high risk of injury to the lower extremities. Head and torso kinematics also were similar between dummies.

The Insurance Institute for Highway Safety (IIHS) has recently developed and evaluated a new side impact barrier to represent the front profile of pickup trucks and sport utility vehicles for a new consumer information program. In the development of this program, two dummies were considered for assessing driver injury risk in side-struck vehicles: EuroSID-2 (50th percentile male dummy) and SID-IIs (5th percentile female dummy). The purpose of this study was to compare injury responses and kinematics for these two dummies in side impact crash tests. The findings suggest that SID-IIs will be more effective in driving relevant improvements in side impact crash protection.

The Insurance Institute for Highway Safety (IIHS) has been conducting frontal offset crash tests of new passenger vehicles and providing comparative crashworthiness information to the public since 1995. This program has resulted in large improvements in frontal crashworthiness largely because vehicle structures have been redesigned to prevent significant collapse of the occupant compartment. In late 2002, IIHS began a side impact crash test program in which the side-impacting barrier has been designed to simulate the geometry of the front ends of SUVs and pickups, which pose a much larger threat in side impacts than the lower front ends of cars. It is anticipated that this program, too, will result in changes in vehicle structure, in this case the structure of the vehicle side pillars and door hardware. Good performance in the side impact test also is likely to require installation of side airbags (or comparable system) to protect the head and/or chest.

The occupants of passenger vehicles struck in the side by another vehicle are more likely to be fatally injured than are occupants of the striking vehicle. The risk of fatality in a side-struck car is higher still when the striking vehicle is a pickup or utility vehicle rather than a passenger car of the same mass. This suggests there are other factors inherent to pickup and utility vehicle design in addition to mass that contribute to this increased risk. In this paper, results are presented from a series of six 90-degree, front-to-side crash tests conducted with both vehicles moving. The side-struck vehicle, a Mercury Grand Marquis with a BioSID (biofidelic side impact dummy) in the driver position, was moving at 24 km/h (15 mi/h) in all tests.

Automatic emergency braking and forward collision warning (FCW) reduce the incidence of police-reported rear-end crashes by 27% to 50%, but these systems may not be effective for preventing rear-end crashes with nonpassenger vehicles. IIHS and Transport Canada evaluated FCW performance with 12 nonpassenger and 7 passenger vehicle or surrogate vehicle targets in five 2021-2022 model year vehicles. The presence and timing of an FCW was measured as a test vehicle traveling 50, 60, or 70 km/h approached a stationary target ahead in the lane center. Equivalence testing was used to evaluate whether the proportion of trials with an FCW (within ± 0.20) and the average time-to-collision of the warning (within ± 0.23 sec) for each target was meaningfully different from a global vehicle car target (GVT).

The Insurance Institute for Highway Safety (IIHS) introduced its updated side-impact ratings test in 2020 to address the nearly 5,000 fatalities occurring annually on U.S. roads in side crashes. Research for the updated test indicated the most promising avenue to address the remaining real-world injuries was a higher severity vehicle-to-vehicle test using a striking barrier that represents a sport utility vehicle. A multi-stiffness aluminum honeycomb barrier was developed to match these conditions. The complexity of a multi-stiffness barrier design warranted research into developing a new dynamic certification procedure. A dynamic test procedure was created to ensure product consistency. The current study outlines the process to develop a dynamic barrier certification protocol. The final configuration includes a rigid inverted T-shaped fixture mounted to a load cell wall. This fixture is impacted by the updated IIHS moving deformable barrier at 30 km/h.