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Impacts between passenger vehicles and heavy vehicles are uniquely severe due to the aggressivity of the heavy vehicles; this is a function of the difference in their geometry and mass. Side crashes with heavy vehicles are a particularly severe crash type due to the mismatch in bumper/structure height that often results in underride and extensive intrusion of the passenger compartment. Underride occurs when a portion of one vehicle, usually the smaller vehicle, moves under another, rendering many of the passenger vehicle safety systems ineffective. Heavy vehicles in the US, including single-unit trucks, truck tractors, semi-trailers, and full trailers, are currently not required to have side underride protection devices. The NTSB, among other groups, has recommended that side underride performance standards be developed and that heavy vehicles be equipped with side underride protection systems that meet those standards.

Aircraft seating systems are evaluated utilizing a variety of impact conditions and select injury measures. Injury measures like the Head Injury Criterion (HIC) are evaluated under standardized conditions using anthropomorphic test devices such as those outlined in 14 CFR part 25. An example test involves decelerating one or more rows of seats and allowing a lap-belted ATD to engage components in front of it, which typically include the seatback and its integrated features. Examples of head contact surfaces include video monitors, various plastic and composite fascia, and a wide range of seat back materials. The HIC, and other injury measures such as Nij, can be calculated during such impacts. It has been shown in other safety applications that the friction between a headform and contact surface can affect the test results.

Aircraft seating systems are evaluated utilizing a variety of impact conditions and selected injury measures. Injury measures like the Head Injury Criterion (HIC) are evaluated under standardized conditions using anthropomorphic dummies such as those outlined in 14 CFR part 25. An example test involves decelerating one or more rows of seats and allowing a lap-belted dummy to impact components in front of it, which typically include the seatback and its integrated features. Examples of head contact surfaces include video monitors, a wide range of seat back materials, and airbags. The HIC, and other injury measures such as Nij, can be calculated during such impacts. A minimum test pulse, with minimum allowable acceleration vs time boundaries, is defined as part of the regulations for a frontal impact. In this study the effects of variations in decelerations that meet the requirements are considered.

More than 900,000 long-haul sleeper cabs are projected to be on the road by 2030. About half of heavy truck occupant fatalities occur in rollovers. This paper discusses the current status of rollover protection systems for occupants in sleeper cabs and describes the outcomes from example crashes with sleeper cab occupants. A virtual testing methodology for evaluation of current designs under rollover conditions and restraint tests utilizing dummies and humans also are described. The paper includes discussion of finite element models used and their validation. Examples of results associated with various restraint system configurations are presented. The results show that incorporating effective lateral restraint is important in providing protection to sleeper cab occupants under rollover conditions.

Rollover test equipment is of interest in the development of rollover protection system designs. The Controlled Rollover Impact System (CRIS) by Exponent and the Jordan Rollover System (JRS) from the original founder of VIA Systems represent two such systems available. The two systems represent significantly different approaches to the same problem; the CRIS utilizes a structure moving over the ground, while the JRS utilizes a rotating vehicle over a moving ground. Finite Element (FE) modeling of CRIS impacts has been presented previously. In this paper, the ability to model the JRS system is demonstrated. A Finite Element model of the JRS was created and compared with an over-the-ground rollover under the same conditions. An analysis using Finite Element models of a production and roll-caged vehicles and Hybrid III dummies with the CRIS and JRS devices under the same impact conditions then was conducted. The results of the analysis are provided and discussed.

The Federal Motor Vehicle Safety Standard 226 (FMVSS 226) ejection mitigation standard proposes to measure the performance of ejection mitigation countermeasures (like side curtain airbags) in side impacts and rollovers. An ejection impactor, consisting of a head form attached to a shaft, is propelled at the airbag system at different locations, and the ability of the system to prevent complete or partial ejection out of the side window portals is documented. The friction between the head form and airbag can affect the performance of the airbag to retain the impactor, particularly when the impactor strikes at the bottom of the airbag near the windowsill level. In this study, friction tests were conducted to measure the friction coefficients between a head form scalp material and airbag fabric, human hair and airbag fabric, and human skin and airbag fabric.

The objective of this study was to demonstrate the ability to reproduce the impact environment occurring in rollover crash tests. There are over 26,000 fatalities and serious injuries annually occurring in rollover accidents in the United States [1]. Many of these are to restrained occupants and their head and spinal injuries have been associated with contact with the roof structure. Finite element models of the Hybrid III dummy and vehicles were used to model the rollover crash tests conducted for Ford. The rollover crash tests involved a production vehicle in a baseline form and one with a roll cage added to it. The impact conditions were incorporated and the results compared with the published test results. The results show that finite element modeling can reproduce the results from rollover crash tests.

A typical production transit bus with vertical pillars of small section size, low gauge and low strength steel, exhibits extensive lateral pillar side-sway collapse (matchboxing) in rollover impacts. This matchboxing allows rollover of the bus onto its roof. LS-DYNA simulations demonstrate that roof pillars of high strength steel or inexpensive E-glass fiber reinforced polymer (FRP) pultrusions can prevent matchboxing and arrest the rollover of the bus. However, for the same space envelope, pultruded FRP pillars can be at least 41% lighter than high strength steel square tubes exhibiting the same bending moment capacity.