RESEARCH & EVALUATION

Vehicle Safety Research

Vehicle Safety

Resources
Reports Library (rosap)

The Office of Vehicle Safety Research and supports U.S. DOT’s and NHTSA’s safety goals by conducting research and safety testing of motor vehicles and motor vehicle equipment. 

NHTSA’s recently published vehicle safety reports are listed chronologically below.



181 Results
Title Report

Variability Study for 50th Percentile Females and Males

The objective of this research is to use parametric human body models (HBMs) to understand how geometric variability among individuals who have the same sex, stature, and body weight may affect the impact responses and injury outcomes, focusing on the midsize male and midsize female populations. We first detailed the methods of quantifying the geometric variations in skeleton and external body surface in midsize male and midsize female occupants using principal component analysis, regression, and residual error analysis. Our findings revealed significant geometric variability in the ribcage and pelvis, whereas variations in the femur and tibia were minimal for both midsize males and females. Based on these geometric analyses, nine midsize male and nine midsize female geometry models were developed, focusing on ribcage and pelvis variations, which account for most of the observed geometric variability. The simplified Global Human Body Modeling Consortium midsize male model was then morphed to match the predicted geometries of the 18 HBMs. Subsequently, 162 impact simulations were conducted under nine impact conditions using the morphed HBMs. Overall, the component-level impact simulations demonstrated relatively small variations in HBM impact responses among models with the same sex, stature, and body weight. However, in the US-NCAP frontal crash simulations, notable variations in injury risk were observed, especially in the front passenger position. These results suggest that geometric variability, even among HBMs with the same sex, stature, and body weight, should not be overlooked when assessing injury risks in severe frontal crashes.

 DOT HS 813 836

NHTSA's DrIIVE Program: Alcohol-Impaired, Drowsy, And Distracted Driving Detection Algorithms

Third of three parts. Driver impairment from drowsiness, distraction, and alcohol intoxication accounts for a substantial percentage of motor vehicle crashes. NHTSA’s Driver Monitoring of Inattention and Impairment Using Vehicle Equipment (DrIIVE) program is aimed at detection and mitigation of driver impairment using data available from inside the vehicle. This project demonstrates that impairment from distraction, drowsiness, and alcohol-intoxication can be detected and, to a large degree, differentiated. Additionally, the project has demonstrated that, for drowsiness, staged alerts can improve driver lane keeping performance at least in the short term. The mitigation track and the general summary are covered in associated reports.

 DOT HS 813 564c

NHTSA's DrIIVE Program: Drowsy Driving Lane Departure Mitigation Countermeasures

Second of three parts. Driver impairment from drowsiness, distraction, and alcohol intoxication accounts for a substantial percentage of motor vehicle crashes. NHTSA’s Driver Monitoring of Inattention and Impairment Using Vehicle Equipment (DrIIVE) program is aimed at detection and mitigation of driver impairment using data available from inside the vehicle. This project demonstrates that impairment from distraction, drowsiness, and alcohol-intoxication can be detected and, to a large degree, differentiated. Additionally, the project has demonstrated that, for drowsiness, staged alerts can improve driver lane keeping performance at least in the short term. The detection track and the general summary are covered in associated reports.

 DOT HS 813 564b

NHTSA's DrIIVE Program: Phase 2 Summary

First of three parts. Driver impairment from drowsiness, distraction, and alcohol intoxication accounts for a substantial percentage of motor vehicle crashes. NHTSA’s Driver Monitoring of Inattention and Impairment Using Vehicle Equipment (DrIIVE) program is aimed at detection and mitigation of driver impairment using data available from inside the vehicle. This project demonstrates that impairment from distraction, drowsiness, and alcohol-intoxication can be detected and, to a large degree, differentiated. Additionally, the project has demonstrated that, for drowsiness, staged alerts can improve driver lane keeping performance at least in the short term. The detection track and the mitigation track are covered in associated reports.

 DOT HS 813 564a

Exploring Driver Adaptation to L2 Driving Automation Using Existing Naturalistic Driving Data

This research explored the concept of behavioral adaptation – how humans respond to introduction of a new technology that serves a specific need of the driver. Three existing naturalistic driving study databases were analyzed: (a) the L2 Naturalistic Driving Study, (b) the Virginia Connected Corridor Elite Naturalistic Driving Study, and (c) the Older Driver L2 Naturalistic Driving Study. The results illustrated an increase in eye off road metrics when L2 systems were active. Results further suggested that driver adaptation was present for high-risk secondary tasks, where there was a significant increase in engagement when L2 systems were active. Additionally, drivers set their vehicle speed above the speed limit more frequently over time, with higher speeds set when L2 systems were active.

 DOT HS 813 827

Considerations for Vehicles With Automated Driving Systems: Seating Preference Study

This VTTI study examined passenger seat belt behavior and seating preference in ADS-DVs with different seating arrangements: conventional, conventional with no manually operated controls, and an unconventional layout with a rear-facing and a forward-facing row of seats. They were recruited under the guise of testing rideshare applications in those three vehicles. Seat belt buckling was observed, with all passengers buckled in prior to requesting to start the ride on 94% of trips. Results also showed passengers preferred sitting in the front row in a conventional vehicle or in forward-facing seats of an unconventional seating layout.

 DOT HS 813 793

Comparative Analysis of Impedance and Gas Sensor Diagnostics for LFP/Graphite Cell Failures

This research investigated early detection of safety risks of lithium-ion battery packs in electric/hybrid vehicles, including rapid electrochemical impedance spectroscopy, sensing of volatile organic compounds, and hydrogen-gas-sensing technology. These sensors monitored four types of cells and packs for failure markers. It evaluated early detection methods during overtemperature and overcharge tests in Li-ion phosphate/graphite cells. The result showed that rapid electrochemical impedance spectroscopy consistently warned earlier for the overtemperature tests. For overcharge tests, volatile organic compound and H₂ gas sensors were more responsive, particularly in larger packs where venting occurred rapidly and before measurable impedance changes occurred.

 DOT HS 813 817

Evaluation of Heavy-Vehicle Collision Warning Interfaces – Follow-On Testing

This follow-on study to a 2015 report evaluated heavy-truck collision warning interfaces focused on the auditory and visual components of a forward collision warning system. This follow-up evaluated nighttime conditions and the implications of delaying the visual component of the alert. Overall, test drivers who received warning alerts responded significantly quicker than drivers who did not receive alerts, similar to the original testing. Delaying the visual component resulted in 100 percent of drivers looking forward to the road as their first response, but did not result in quicker brake response times versus when not delaying the visual alert.

 DOT HS 813 825

Conventional Vehicle Driver and Automated Driving System-Equipped Vehicle Interactions

This report describes findings of an on-road experiment that investigated drivers’ behaviors around a vehicle identified as a “self-driving” vehicle. Researchers collected data on public highways using a research vehicle, which on different drives had the outward appearance of either a conventional vehicle or an ADS mockup vehicle. During data collection trips on a fixed freeway route, the behavior of nearby drivers and their vehicles were observed and recorded. Observers noted that nearby drivers exhibited longer glances, more surprised expressions, and occasional gestures or even camera use when approaching or passing the mockup research vehicle, and drivers generally took longer to pass it. However, objective measures of potentially unsafe actions (e.g., cut-ins, tailgating) showed no statistically significant differences between the mockup research vehicle and conventional vehicle.

 DOT HS 813 751

Low-Cost Pedestrian Safety Zone Case Study

A previous study by Blomberg and Cleven (1998) developed a pedestrian safety zone approach in Phoenix, Arizona, and Chicago, Illinois, focusing on pedestrian safety countermeasures in subsets of the cities that had experienced a high number of crashes involving people 65 and older. It proved efficient deploying countermeasures, significantly reducing the targeted pedestrian crashes in Phoenix. This original zone process, however, still needed significant resources to address the entire city, and required a relatively long time to plan and implement. The primary objectives of the present study included adapting the previous zones approach to be implementable quickly by cities using their resources and demonstrating the resulting low-cost pedestrian safety zones approach in several cities. Three cities—Gainesville, Florida; Kalamazoo, Michigan; and Saint Paul, Minnesota—agreed to demonstrate the low-cost zones approach. Each site prepared a case study report documenting the activities reported here. The approach appeared flexible and effective in all three cities. The discussion section of this report includes ideas for supporting more widespread use of the technique.

 DOT HS 813 747