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In this study, the occupant containment characteristics of automotive laminated safety glass in side window applications was evaluated through two full-scale, full-vehicle dolly rollover crash tests. The dolly rollover crash tests were performed on sport utility vehicles equipped with heat-strengthened laminated safety glass in the side windows in order to: (1) evaluate the capacity of laminated side window safety glass to contain unrestrained occupants during rollover, (2) analyze the kinematics associated with unrestrained occupants during glazing interaction and ejection, and (3) to identify laminated side window safety glass failure modes. Dolly rollovers were performed on a 1998 Ford Expedition and a 2004 Volvo XC90 at a nominal speed of 43 mph, with unbelted Hybrid II Anthropomorphic Test Devices (ATDs) positioned in the outboard seating positions.

Crash tests of vehicles by striking deformable barriers are specified by Government programs such as FMVSS 214, FMVSS 301 and the Side Impact New Car Assessment Program (SINCAP). Such tests result in both crash partners absorbing crush energy and moving after separation. Compared with studying fixed rigid barrier crash tests, the analysis of the energy-absorbing behavior of the vehicle side (or rear) structure is much more involved. Described in this paper is a methodology by which analysts can use such crash tests to determine the side structure stiffness characteristics for the specific struck vehicle. Such vehicle-specific information allows the calculation of the crush energy for the particular side-struck vehicle during an actual collision – a key step in the reconstruction of that crash.

Crash tests of vehicles by striking deformable barriers are specified by Government programs such as FMVSS 214, FMVSS 301 and the Side Impact New Car Assessment Program (SINCAP). Such tests result in both crash partners absorbing crush energy and moving after separation. Compared with studying fixed rigid barrier crash tests, the analysis of the energy-absorbing behavior of the vehicle side (or rear) structure is much more involved. Described in this paper is a methodology by which analysts can use such crash tests to determine the side structure stiffness characteristics for the specific struck vehicle. Such vehicle-specific information allows the calculation of the crush energy for the particular side-struck vehicle during an actual collision – a key step in the reconstruction of that crash.

One element of primary interest in the analysis and reconstruction of vehicle collisions is an evaluation of impact severity. The severity of an impact is commonly quantified using vehicle closing speeds and/or velocity change (delta-V). One fundamental methodology available to determine the closing speed and corresponding velocity change is an analysis of the collision based on a combination of the principles of Conservation of Momentum and Conservation of Energy. A critical element of this method is an assessment of the amount of kinetic energy that is dissipated during plastic structural deformation (crush) of the involved vehicles. This crush energy assessment is typically based on an interpolation or an extrapolation of data collected during National Highway Traffic Safety Administration (NHTSA) sponsored crash testing at nominal speeds of 30 or 35 mph.

Low- to moderate-speed motor vehicle collisions are common roadway occurrences that are generally associated with low rates of reported injury. While such complaints are generally infrequent, claims of injuries resulting from low- to moderate-speed motor vehicle collisions persist. A limited body of literature using quantitative techniques and full-scale crash tests is available to assess the injury potential associated with such collisions. Prior studies have analyzed occupant kinematics and kinetics as well as human injury risk in low- to moderate-speed collisions with older vehicle vintages but do not assess the effects of updated vehicle interior designs and occupant protection devices reflective of efforts to optimize occupant kinematics and reduce occupant loading and injury risk in more modern vehicles.

The process of design inherently involves consideration of risk trade offs; intervening to reduce one risk often increases another. In addition to creating a design for the intended function of the product, a rational process of risk management involves prediction of risk through design analysis, statistical evaluation of the history of similar products, and potentially multidisciplinary teams to address diverse causes of risk. As a case study, this paper examines the benefits of using one class of fire retardant to reduce risk of vehicle fire injuries and the countervailing health risk due to increased quantities of fire retardants released in the interior environment. Data sources for fire and health risk were researched and interpreted for use in the analysis. Information needed to reduce the uncertainties in the risk predictions are identified for future refinements to the conclusions.

A substantial percentage of serious and fatal injuries sustained by motor vehicle occupants occur in lateral impact collisions, and approximately one third of these injuries involve a far-side occupant. A center airbag, deploying inboard of the front seat occupants, has been integrated into certain vehicles to reduce far-side occupant excursion, to limit occupant interactions with the vehicle interior and/or another occupant, and to reduce occupant loading and injury potential. A series of sled tests was conducted to better understand the efficacy and limitations of a center airbag under a variety of high-speed lateral impact conditions in an environment outside of the production design. A production-level driver’s seat equipped with a seat-mounted center airbag was installed onto an open-air sled. A 50th percentile male SID H-3 was placed in the seat and restrained by a three-point seat belt equipped with retractor and buckle pretensioners.

Test methods for vehicle safety development are either based on the movement of a vehicle into a stationary barrier or the movement of a barrier into a stationary vehicle. When deemed necessary, a two-moving-vehicle impact is approximated by modifying the impact motion between the moving and stationary objects. For example, the Federal Motor Vehicle Safety Standard (FMVSS) 214 side-impact crash test procedure [1] approximates the lateral impact of a moving vehicle into the side of another moving vehicle by using a moving barrier with wheels crabbed so that the velocity vector of the barrier is not collinear with its longitudinal axis. Such approximations are valid when the post-impact motions of the two vehicles are not to be evaluated. Similarly, the published data indicates that historic analyses of motorcycle accidents and the advancements in motorcycle safety designs have been based, in large part, on single-moving-vehicle crash tests.

There is a paucity of data regarding the potential for pediatric cervical spine injury as a result of acceleration of the head with no direct impact during automotive crashes. Sled tests were conducted using a 3-year-old anthropomorphic test device (ATD) to investigate the effect of restraint type and crash severity on the risk of pediatric inertial neck injury. At higher crash severities, the ATD restrained by only the vehicle three-point restraints sustained higher peak neck tension, peak neck extension and flexion moments, neck injury criterion (Nij) values, peak head accelerations, and HIC values compared to using a forward-facing child restraint system (CRS). The injury assessment reference values (IARVs) for peak tension and Nij were exceeded in all 48 and 64 kph delta-V tests using any restraint type.

Low-speed sideswipe collisions between tractor-semitrailers and passenger vehicles can result in large movements and extensive areas of visible damage to the passenger vehicle. However, depending on the specifics of the collision, the resulting crash pulse may be extended, and the vehicle accelerations correspondingly low. Research regarding the impact environment and resulting injury potential of the occupants during these types of impacts is limited. Five full-scale crash tests utilizing a tractor-semitrailer and a passenger car were conducted to explore vehicle responses during these types of collisions for both the passenger car and the tractor-trailer. The test vehicles included a loaded van semitrailer pulled by a tractor and three identical mid-sized sedans. Instrumentation on the sedans included accelerometers and rotational rate sensors, and the vehicle and occupant kinematics were recorded using onboard and off-board real-time and high-speed video cameras.

With growing environmental concerns associated with gas-powered vehicles and busier city streets, micro-mobility modes, including traditional bicycles and new technologies, such as electric scooters (e-scooters), are becoming solutions. In 2018, e-scooter usage overtook other shared micro-mobility modes with over 38 million e-scooter trips taken. Concurrently, the societal concern regarding the safety of these devices is also increasing. To examine the types of injuries associated with e-scooters and bicycles, the National Electronic Injury Surveillance System (NEISS), a probability sample of US hospitals that collects information from emergency room (ER) visits related to consumer products, was utilized. Records from September 2017 to December 2018 were extracted, and those associated with powered scooters were identified. Injury distributions by age, sex, race, treatment, diagnosis, and location on the body were explored.

Occupant ejection may occur during planar and rollover collisions. These ejections can be associated with serious/fatal injuries. Occasionally, occupants will allege that they were wearing a seatbelt immediately before the ejection occurred. Some accident investigators have opined that a seatbelt became disengaged due to collision forces and/or occupant interactions, leaving the occupant essentially unrestrained and exposed to ejection from the vehicle. We present three case studies of collisions with documented seatbelt disengagement at or during the collision, as well as three controlled tests. The release of the seatbelt was always associated with dire consequences for the occupant's outboard upper extremity. Evidence of seatbelt webbing interaction with the occupant was always evident, and the interaction of the belt with the vehicle interior trim was also apparent.

It is widely accepted that a motorcycle helmet will reduce the risk of a serious brain injury during an accident through energy dissipation. Currently, there is no literature on what happens to a motorcycle helmet after repeated significant impacts or why it cannot be re-used according to the DOT label. It is also unclear experimentally if the foam liner is permanently affected after repeated impacts. In this study, we repetitively dropped one style of DOT-approved motorcycle helmet using a drop tower system in accordance with FMVSS 218. Helmeted Hybrid III and magnesium headforms were dropped onto a flat anvil with contact to the apical region of the helmets. Strips of pressure-indicating film were placed in the mid-sagittal plane between the foam liner and the headform. Headform accelerations and head injury criterion (HIC) for the Hybrid-III headform were calculated for each drop test. There was a trend for maximum headform acceleration to increase with the number of impacts.

Frontal crashes are the most common crash mode in the US vehicle fleet, and a large proportion of these crashes are “fender-benders” or low-speed collisions. This, among other considerations, led the Insurance Institute for Highway Safety (IIHS) to conduct a series of low-speed front and rear bumper impact tests. These crash tests have been performed on passenger vehicles manufactured by various manufacturers since 1970 and continuing through the 2009 model year. Test data and video for individual tests are available through IIHS’s online data portal, most extensively for model years 2007 to 2009. While IIHS’s test protocol varied over the years, these tests specified, in part, a full engagement impact of the tested vehicle into a rigid, bumper-shaped barrier covered with an energy absorber. Although IIHS reported the closing speed for each test, they did not report the separation speed or crash pulse duration.

Over the past decade, there has been an increase in awareness and concern about the occurrence and long-term effects of concussions. Traumatic brain injury (TBI)-related emergency department (ED) visits associated with motor vehicle collisions, including patients with a diagnosis of concussion or mild TBI (mTBI), have increased while deaths and hospital admissions related to TBI have decreased. The diagnostic criteria for concussion have evolved and broadened, and based on current assessments and diagnostic imaging techniques, there are often no objective findings, yet a diagnosis of concussion may still be rendered. Clinical assessment of concussion may be based only on patient-reported symptoms and history, making it difficult to objectively relate the reported increase in TBI-related ED visits due to motor vehicle collisions to specific collision parameters.

The subject of whether roof deformation in and of itself causes occupant injury in rollover accidents has been emotionally, scientifically and legally contested for decades. Since the publication of the earliest scientific research on the issues of automobile roof strength and non-ejected passenger protection in rollover crashes, the two views have been generally diametrically opposed to one another, and the debate continues. In order to gain perspective on the subject, the question must be answered as to how effective past and current automotive vehicle roof structures, designed to meet current government and industry standards, have proven to be in protecting vehicle occupants during real-world accidents involving the rollover of the vehicle they occupy.

Decades after their introduction, seat belts remain the most important safety innovation in automotive history. Seat belt usage remains the single most effective way to minimize the risk of injury or death in severe crash events. Despite having matured, seat belts continue to evolve and improve and are expected to play an equally critical role in future passenger vehicles as increasing automation leads to changes in occupant compartment design and occupant-to-vehicle interaction. In this paper, an overview of major technical milestones in the development of seat belts is presented, ranging from the earliest lap belts to today’s systems that seamlessly synthesize and integrate information from a variety of sensors to prepare the restraints for an imminent crash. A brief overview of contemporary regulatory events is also provided, illustrating how regulatory actions have followed and occasionally driven the development and proliferation of various aspects of occupant restraints.

Federal Motor Vehicle Safety Standard No. 213 specifies requirements for child restraint systems used in motor vehicles and was first introduced by the National Highway Safety Bureau in 1971. In 1981, the standard was modified to require dynamic testing of child restraints. Over the following 21 years, Standard No. 213 was modified on numerous occasions, most recently in June of 2003. This paper outlines the history of Standard No. 213 with a discussion of the changes that have been proposed, the comments submitted to NHTSA in response to these proposed changes, and NHTSA's final decision (rule making) regarding which changes to adopt. Detailed discussion is included regarding NHTSA's May 2002 proposal to change the crash pulse, test dummies, injury criteria, and test bench required as part of the dynamic testing. The 2002 proposal also included expansion of the standard to cover child restraints for children weighing up to 65 pounds.

Field accident data and vehicle crash and sled testing indicate that occupant kinematics, loading, and associated injury risk generally increase with crash severity. Further, these data demonstrate that the use of restraints, such as three-point belts, provides mitigation of kinematics and reduction in loading and injury potential. This study evaluated the role of seat belts in controlling occupant kinematics and reducing occupant loading in moderate severity frontal collisions. Frontal tests with belted and unbelted anthropomorphic test devices (ATDs) in the driver and right front passenger seats were performed at velocity changes (delta-Vs) of approximately 19 kph (12 mph) and 32 kph (20 mph) without airbag deployment. At the lower-moderate severity (19 kph), motion of the belted ATDs was primarily arrested by seat belt engagement, while motion of the unbelted ATDs was primarily arrested by interaction with forward vehicle structures.

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.