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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).

Since the introduction of ice crystal icing certification requirements [1], icing facilities have played an important role in demonstrating compliance of aircraft air data probes, engine probes, and increasingly, of turbine engines. Most sea level engine icing facilities use the freezing-out of a water spray to simulate ice crystal icing conditions encountered at altitude by an aircraft in flight. However, there are notable differences in the ice particles created by freeze-out versus those observed at altitude [2, 3, 4]. Freeze-out crystals are generally spherical as compared to altitude crystals which have variable crystalline shapes. Additionally, freeze-out particles may not completely freeze in their centres, creating a combination of super-cooled liquid and ice impacting engine hardware. An alternative method for generating ice crystals in a test facility is the grinding of ice blocks or cubes to create irregular shaped crystals.

Aerodynamic technologies for light-duty vehicles were evaluated through full-scale testing in a large low-blockage closed-circuit wind tunnel equipped with a rolling road, wheel rollers, boundary-layer suction and a system to generate road-representative turbulent flow. This work was part of a multi-year, multi-vehicle study commissioned by Transport Canada and Environment and Climate Change Canada, and carried out in cooperation with the US EPA, to support the evaluation of light-duty-vehicle greenhouse-gas-emission regulations. A 2016 paper reported drag-reduction measurements for technologies such as active grille shutters, production and custom underbody treatments, air dams, ride height control and combinations of these. This paper describes an extension to that work and addresses vehicle aerodynamics in three ways.

Current recommendations for restraining child occupants are based on biomechanical testing and data from national and international field studies primarily conducted prior to 2011. We hypothesized that analysis to identify factors associated with pediatric injury in motor-vehicle crashes using a national database of more recent police-reported crashes in the United States involving children under age 13 where type of child restraint system (CRS) is recorded would support previous recommendations. Weighted data were extracted from the National Automotive Sampling System General Estimates System (NASS-GES) for crash years 2010 to 2015. Injury outcomes were grouped as CO (possible and no injury) or KAB (killed, incapacitating injury, non-incapacitating injury). Restraint was characterized as optimal, suboptimal, or unrestrained based on current best practice recommendations. Analysis used survey methods to identify factors associated with injury.

The SAE G-27 committee was tasked by ICAO to develop a performance-based packaging standard for lithium batteries transported as cargo on aircraft. The standard details test criteria to qualify packages of lithium batteries & cells for transportation as cargo on-board passenger aircraft. Lithium batteries and cells have been prohibited from shipment as cargo on passenger aircraft since 2016. This paper summarizes the results of the tests conducted by Transport Canada and National Research Council Canada to support the development of this standard with evidence-based recommendations. It includes a description of the test specimens, the test set up, instrumentation used, and test procedures following the standard as drafted to date. The study considered several lithium-ion battery and cell chemistries that were tested under various proposed testing scenarios in the draft standard.

Recent field data have shown that the occupant protection in vehicle rear seats failed to keep pace with advances in the front seats likely due to the lack of advanced safety technologies. The objective of this study was to optimize advanced restraint systems for protecting rear seat occupants with a range of body sizes under different frontal crash pulses. Three series of sled tests (baseline tests, advanced restraint trial tests, and final tests), MADYMO model validations against a subset of the sled tests, and design optimizations using the validated models were conducted to investigate rear seat occupant protection with 4 Anthropomorphic Test Devices (ATDs) and 2 crash pulses.

Recent field data have shown that the occupant protection in vehicle rear seats failed to keep pace with advances in the front seats likely due to the lack of advanced safety technologies. The objective of this study was to optimize advanced restraint systems for protecting rear seat occupants with a range of body sizes under different frontal crash pulses. Three series of sled tests (baseline tests, advanced restraint trial tests, and final tests), MADYMO model validations against a subset of the sled tests, and design optimizations using the validated models were conducted to investigate rear seat occupant protection with 4 Anthropomorphic Test Devices (ATDs) and 2 crash pulses.

Occupant stature and body shape may have significant effects on injury risks in motor vehicle crashes, but the current finite element (FE) human body models (HBMs) only represent occupants with a few sizes and shapes. Our recent studies have demonstrated that, by using a mesh morphing method, parametric FE HBMs can be rapidly developed for representing a diverse population. However, the biofidelity of those models across a wide range of human attributes has not been established. Therefore, the objectives of this study are 1) to evaluate the accuracy of HBMs considering subject-specific geometry information, and 2) to apply the parametric HBMs in a sensitivity analysis for identifying the specific parameters affecting body responses in side impact conditions. Four side-impact tests with two male post-mortem human subjects (PMHSs) were selected to evaluate the accuracy of the geometry and impact responses of the morphed HBMs.

Law enforcement officers (LEO) make extensive use of vehicles to perform their jobs, often spending large portions of a shift behind the wheel. Few LEO vehicles are purpose-built; the vast majority are modified civilian vehicles. Data from the field indicate that LEO suffer from relatively high levels musculoskeletal injury that may be due in part to poor accommodation provided by their vehicles. LEO are also exposed to elevated crash injury risk, which may be exacerbated by a compromise in the performance of the occupant restraint systems due to body-borne equipment. A pilot study was conducted to demonstrate the application of three-dimensional anthropometric scanning and measurement technology to address critical concerns related to vehicle design. Detailed posture and belt fit data were gathered from five law enforcement officers as they sat in the patrol vehicles that they regularly used and in a mockup of a mid-sized vehicle.

The objective of this study is to develop a method that uses a combination of field data analysis, naturalistic driving data analysis, and computational simulations to explore the potential injury reduction capabilities of integrating passive and active safety systems in frontal impact conditions. For the purposes of this study, the active safety system is actually a driver assist (DA) feature that has the potential to reduce delta-V prior to a crash, in frontal or other crash scenarios. A field data analysis was first conducted to estimate the delta-V distribution change based on an assumption of 20% crash avoidance resulting from a pre-crash braking DA feature. Analysis of changes in driver head location during 470 hard braking events in a naturalistic driving study found that drivers’ head positions were mostly in the center position before the braking onset, while the percentage of time drivers leaning forward or backward increased significantly after the braking onset.

Passenger car side impact crash tests and sled tests were conducted to investigate the influence of booster seats, near-side occupant characteristics and vehicle interiors on the responses of the Q6/Q6s child ATD positioned in the rear, far-side seating location. Data from nine side impact sled tests simulating a EuroNCAP AEMD barrier test were analyzed with data obtained from 44 side impact crash tests. The crash tests included: FMVSS 214 and IIHS MDB, moving car-to-stationary car and moving car-to-moving car. A Q6 or prototype Q6s ATD was seated on the far-side, using a variety of low and high back booster seats. Head and chest responses were recorded and ATD motions were tracked with high-speed videos. The vehicle lateral accelerations resulting from MDB tests were characterized by a much earlier and more rapid rise to peak than in tests where the bullet was another car.

The aging population is a growing concern as the increased fragility and frailty of the elderly results in an elevated incidence of injury as well as an increased risk of mortality and morbidity. To assess elderly injury risk, age-specific computational models can be developed to directly calculate biomechanical metrics for injury. The first objective was to develop an older occupant Global Human Body Models Consortium (GHBMC) average male model (M50) representative of a 65 year old (YO) and to perform regional validation tests to investigate predicted fractures and injury severity with age. Development of the GHBMC M50 65 YO model involved implementing geometric, cortical thickness, and material property changes with age. Regional validation tests included a chest impact, a lateral impact, a shoulder impact, a thoracoabdominal impact, an abdominal bar impact, a pelvic impact, and a lateral sled test.

Eight whole fresh-frozen cadavers (6 female, 2 male) that were elderly and/or female were laterally impacted using UMTRI's dual-sled side-impact test facility. Cadavers were not excluded on the basis of old age or bone diseases that affect tolerance. A thinly padded, multi-segment impactor was used that independently measured force histories applied to the shoulder, thorax, abdomen, greater trochanter, iliac wing, and femur of each PMHS. Impactor plates were adjusted vertically and laterally toward the subject so that contact with body regions occurred simultaneously and so that each segment contacted the same region on every subject. This configuration minimized the effects of body shape on load sharing between regions. Prior to all tests, cadavers were CT scanned to check for pre-existing skeletal injuries. Cadavers were excluded if they had pre-existing rib fractures or had undergone CPR.

A laboratory study of posture and belt fit was conducted with 46 men and 51 women, 61% of whom were age 60 years or older and 32% age 70 years or older. In addition, 28% of the 97 participants were obese, defined as body mass index ≥ 30 kg/m2. A mockup of a passenger vehicle driver's station was created and five belt anchorage configurations were produced by moving the buckle, outboard-upper (D-ring), and outboard-lower anchorages. An investigator recorded the three-dimensional locations of landmarks on the belt and the participant's body using a coordinate measurement machine. The location of the belt with respect to the underlying skeletal structures was analyzed, along with the length of belt webbing. Using linear regression models, an increase in age from 20 to 80 years resulted in the lap belt positioned 18 mm further forward relative to the pelvis, 26 mm greater lap belt webbing length, and 19 mm greater shoulder belt length.

NHTSA estimates that more than half of the lives saved (168,524) in car crashes between 1960 and 2002 were due to the use of seat belts. Nevertheless, while seat belts are vital to occupant crash protection, safety researchers continue efforts to further enhance the capability of seat belts in reducing injury and fatality risk in automotive crashes. Examples of seat belt design concepts that have been investigated by researchers include inflatable, 4-point, and reverse geometry seat belts. In 2011, Ford Motor Company introduced the first rear seat inflatable seat belts into production vehicles. A series of tests with child and small female-sized Anthropomorphic Test Devices (ATD) and small, elderly female Post Mortem Human Subjects (PMHS) was performed to evaluate interactions of prototype inflatable seat belts with the chest, upper torso, head and neck of children and small occupants, from infants to young adolescents.

Lateral impact tests were performed using seven male post-mortem human subjects (PMHS) to characterize the force-deflection response of contacted body regions, including the lower abdomen. All tests were performed using a dual-sled, side-impact test facility. A segmented impactor was mounted on a sled that was pneumatically accelerated into a second, initially stationary sled on which a subject was seated facing perpendicular to the direction of impact. Positions of impactor segments were adjusted for each subject so that forces applied to different anatomic regions, including thorax, abdomen, greater trochanter, iliac wing, and thigh, could be independently measured on each PMHS. The impactor contact surfaces were located in the same vertical plane, except that the abdomen plate was offset 5.1 cm towards the subject.

This study evaluated the biomechanical performance of a rear-seat inflatable seatbelt system and compared it to that of a 3-point seatbelt system, which has a long history of good real-world performance. Frontal-impact sled tests were conducted with Hybrid III anthropomorphic test devices (ATDs) and with post mortem human subjects (PMHS) using both restraint systems and a generic rear-seat configuration. Results from these tests demonstrated: a) reduction in forward head excursion with the inflatable seatbelt system when compared to that of a 3-point seatbelt and; b) a reduction in ATD and PMHS peak chest deflections and the number of PMHS rib fractures with the inflatable seatbelt system and c) a reduction in PMHS cervical-spine injuries, due to the interaction of the chin with the inflated shoulder belt. These results suggest that an inflatable seatbelt system will offer additional benefits to some occupants in the rear seats.

The NASS-CDS (1998-2008) and CIREN datasets were analyzed to identify factors contributing to abdominal injury in crash environments where belt use and airbag deployment are common. In frontal impacts, the percentage of occupants sustaining abdominal injury is three times higher for unbelted compared to belted front-row adult occupants (p≺0.0001) at both AIS2+ and AIS3+ injury levels. Airbag deployment does not substantially affect the percentage of occupants who sustain abdominal injuries in frontal impacts (p=0.6171), while belt use reduces the percentage of occupants sustaining abdominal injury in both nearside and farside crashes (p≺0.0001). Right-front passengers in right-side impacts have the highest risk (1.91%) of AIS 3+ abdominal injury (p=0.03). The percentage of occupants with AIS 3+ abdominal injuries does not vary with age for frontal, nearside, or farside impacts.

This study outlines a protocol for image data collection acquired from human volunteers. The data set will serve as the foundation of a consolidated effort to develop the next generation full-body Finite Element Analysis (FEA) models for injury prediction and prevention. The geometry of these models will be based off the anatomy of four individuals meeting extensive prescreening requirements and representing the 5th and 50th percentile female, and the 50th and 95th percentile male. Target values for anthropometry are determined by literature sources. Because of the relative strengths of various modalities commonly in use today in the clinical and engineering worlds, a multi-modality approach is outlined. This approach involves the use of Computed Tomography (CT), upright and closed-bore Magnetic Resonance Imaging (MRI), and external anthropometric measurements.

The objectives of this study were to examine the response, repeatability, and injury predictive ability of the Hybrid III small-female dummy to static out-of-position (OOP) deployments using a depowered driver-side airbag. Five dummy tests were conducted in two OOP configurations by two different laboratories. The OOP configurations were nose-on-rim (NOR) and chest-on-bag (COB). Four cadaver tests were conducted using unembalmed small-female cadavers and the same airbags used in the dummy tests under similar OOP conditions. One cadaver test was designed to increase airbag loading of the face and neck (a forehead-on-rim, or FOR test). Comparison between the dummy tests of Lab 1 and of Lab 2 indicated the test conditions and results were repeatable. In the cadaver tests no skull fractures or neck injuries occurred. However, all four cadavers had multiple rib fractures.