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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.

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.

Properly restraining a child in an automotive seat may require the use of a weight- and size-appropriate Child Restraint System (CRS). Proper installation of the CRS is a critical part of protecting a child during a motor vehicle collision. During a collision, child occupants sometimes exert enough force on the restraint system to generate load marks on the CRS and the vehicle restraint system. These marks are often relied upon by investigators to determine if the child occupant was properly restrained at the time of the collision. This paper is an observational study of the load marks generated from sled testing that was conducted using Hybrid III 3-year-old and 6-year-old Anthropomorphic Test Devices (ATDs). Tests were conducted with various child restraint systems that were installed in accordance with the manufacturer's recommendations as well as installed improperly. Additional tests were conducted with the ATDs without the use of a CRS.

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.

This study investigates the technique used and forces applied on the latch plate and buckle during typical seat belt operation and driving conditions. These techniques and forces are relevant to whether the latch plate can be partially engaged with the buckle during typical operation and whether the latch plate will dislodge during vehicle operation. In addition to studying the insertion of the latch plate, we examined the tensile forces that are applied to the latch plate and buckle during typical, non-crash driving conditions, and how these forces compare to the performance requirements established by the National Highway Traffic Safety Administration (NHTSA) as part of Federal Motor Vehicle Safety Standards (FMVSS) 209. These tensile forces are important in understanding whether the latch plate is likely to dislodge from the buckle if it is in a position of partial engagement.

Sound localization of a backup alarm is important in situations when vehicles are reversing. Previous work has demonstrated the effects of ambient noise level and the spectral content of the backup alarm on localization. In the current study, we investigate the effects of backup alarm mounting location on localization performance. To address this question, we asked blindfolded listeners to localize backup alarms installed in positions that provided either direct (e.g., installed on the outer rear aspect of the vehicle) or indirect (e.g., installed within the inner frame rails of the vehicle) sound propagation paths to the listener. Additionally, we explored the effects of ambient noise level and the direction of origin of the alarm (behind, in front of, or to the left or right of the listener), and the interactions among all three factors (alarm location, ambient noise, and alarm direction relative to the listener).

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.

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.

Obesity is a growing problem in the general population. Recent studies have suggested a link between occupant anthropometry and injury risk in motor vehicle accidents. Adult subjects covering a range of heights, weights, and body mass index (BMI) were seated in passenger cars and asked to adjust the seat and restraint to a comfortable driving position. Differences75 in driver position and clearance measures between normal weight, overweight, and obese occupants were assessed. Occupant height was found to be a good predictor of some seating position and clearance measures, while BMI was found to be a better predictor of others. Relationships were also found relating waist circumference to measures of seating position and clearance. The results of this study are essential in developing quantitative models to investigate relationships between anthropometry and injury potential.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.