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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.

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.

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).

Vision plays a key role in the safe and proper operation of vehicles. To safely navigate, drivers constantly scan their environments, which includes attending to the outside environment as well as the inside of the driver compartment. For example, a driver may monitor various instruments and road signage to ensure that they are traveling at an appropriate speed. Although there has been work done on naturalistic driver gaze behavior, little is known about what information drivers glean while driving. Here, we present a methodology that has been used to build a database that seeks to provide a framework to supply answers to various ongoing questions regarding gaze and driver behavior. We discuss the simultaneous recording of eye-tracking, head rotation kinematics, and vehicle dynamics during naturalistic driving in order to examine driver behavior with a particular focus on how this correlates with gaze behavior.

The usage of rearview camera displays and their effectiveness on drivers' capability to avoid unexpected obstacles during four common backing tasks (i.e., parallel parking, backing between two vehicles, backing down a driveway, backing out of a garage) was evaluated on a closed-course with stationary confederate vehicles, signage, and lane markings. The obstacle consisted of either a stationary or a moving target that appeared to the rear of the test vehicle. Eye movements and vehicle dynamics measurements (i.e., longitudinal acceleration, brake displacement) were recorded, in addition to obstacle hit/avoidance rates. Performance was assessed for four rearview camera (RVC) conditions: small center-stack display (SD), large center-stack display (i.e., navigation screen) (LD), in-mirror display (IMD), and no display (ND).

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.

Despite public expectations that autonomous vehicles should be able to avoid most accidents, the existing fleet of autonomous test vehicles has demonstrated this is simply not the case. An explanation for some of these accidents has been that these vehicles do not drive like humans and therefore do not exhibit certain driving patterns expected by human drivers. With the high likelihood of a gradual integration of autonomous vehicles into our traffic system in the future, there will be a need for such vehicles to adapt to, and mimic, human driving. Although much work has been done to understand human behavior and performance in driving, it has been mostly geared towards defining human capabilities and limitations. Little work has been done on the interactions between human-driven and autonomous vehicles.

Certain ankylosing spondyloarthropathies such as ankylosing spondylitis (AS) or diffuse idiopathic skeletal hyperostosis (DISH) can substantially alter clinicopathologic spine biomechanics as well as injury mechanisms in rear-end motor vehicle collisions. AS is an inflammatory disease which can lead to structural impairments of the spine secondary to flowing ossification along the spinal column, including ossification across the spinal discs, facet joints, and ligaments, and it has also been associated with diffuse osteoporosis of the spine. DISH is characterized by excess bone formation along the spinal column, encompassing the annulus and forming the thickest and strongest bridging osteophytes over adjacent vertebral bodies at the level of the disc space. In both conditions the spine is mechanically stiffened and generally more kyphotic than a healthy spine.

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.

Although great progress has been made to improve the safety and performance of autonomous vehicles with the ultimate goal of meeting the public expectation of preventing most accidents, the current fleet of autonomous vehicles being tested continues to demonstrate that we still remain distant from that holy grail. One rationalization for some of these accidents has been that different maneuvers performed by such cars are not human-like (i.e. they do not display certain driving patterns to which human drivers are accustomed to). With that in mind, it would be hard to dispute the need for such vehicles to adapt to and somewhat imitate human driving in order to gradually integrate human-driven traffic in the future.

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.

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.

Low-speed sideswipe collisions between tractor-semitrailers and passenger vehicles may result in large areas of visible damage to the passenger vehicle. However, due to the extended contact that occurs during these impacts, it is typical in these incidents for the crash pulse duration to be long and the vehicle accelerations to be 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 the occupant responses during these types of collisions. The test vehicles included a van semitrailer pulled by a tractor and three identical mid-sized sedans. The occupants of the sedans included an instrumented Hybrid III 5th -percentile-male anthropomorphic test device (ATD) in the driver's seat and an un-instrumented Hybrid III 5th -percentile-female ATD in the left rear seat.