Vehicle Safety

Resources

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.

39 Results
System-Level RESS Safety and Protection Test Procedure Development, Validation, and Assessment–Final Report

The technical report, “System Level RESS Safety and Protection Test Procedure Development, Validation, and Assessment” was prepared for NHTSA by Argonne National Laboratory via Interagency Agreement DTNH22-15-X-00513. The project originally initiated in August 2015 with a cost of $550,000. The draft report was received by NHTSA in December of 2017 and circulated for agency comments. These comments were assessed, and appropriate revisions were included in this final report.

A Test Track Comparison of the Global Vehicle Target and NHTSA’s Strikeable Surrogate Vehicle

This report compares forward collision warning alert and crash imminent braking intervention onset timing elicited by the Global Vehicle Target Revision E (GVT) to that observed during identical tests performed with NHTSA’s strikeable surrogate vehicle benchmark using three light vehicles and three rear-end crash scenarios were used for this evaluation. A secondary objective of this study was to describe some of the test-track-based use considerations related to the GVT, namely the dynamic stability and in-the-field reconstruction time after being struck by a test vehicle. GVT stability was assessed using straight line and curved path maneuvers at various speeds and lateral accelerations. Reconstruction times were examined using different impact speeds, directions of impact, and assembly crew sizes. Analyses suggest the Mercedes C300 and Volvo S90 responded similarly to both the GVT and SSV, with the Volvo S90 responses being the most consistent.

Statistics of Light-Vehicle Pre-Crash Scenarios Based on 2011–2015 National Crash Data

This report defines a new set of 36 distinct pre-crash scenarios that represent the crash population of light-vehicles (LVs) based on data from the 2011-2015 Fatality Analysis Reporting System (FARS) and National Automotive Sampling System General Estimates System (GES) crash databases. LVs include all passenger cars, vans, minivans, sport utility vehicles, and light pickup trucks with gross vehicle weight ratings less than or equal to 10,000 pounds. Pre-crash scenarios describe vehicle movements and the critical event that made the crash imminent (i.e., something occurred that made the collision possible). The 36 pre-crash scenarios are arranged into nine groups: control loss, road departure, animal, pedestrian, pedalcyclist, lane change, opposite direction, rear-end, and crossing paths. These nine groups account for 24,534 (94%) fatal crashes and an estimated 5,020,000 (89%) of all police-reported crashes based on the yearly average of the 2011-2015 FARS and GES crash databases, respectively. This report also provides crash characteristics for each pre-crash scenario and group in terms of environmental conditions, road geometry, crash location, vehicle/crash-related factors, driver characteristics, attempted avoidance maneuver, traffic violations, and crash contributing factors.

Technical Evaluation Of the TRL Pedestrian Upper Legform

The upper legform impactor was introduced by Transport Research Laboratory (TRL) to address injuries to the upper leg, pelvis, and hip of a pedestrian when struck by a vehicle. It is new to NHTSA and was evaluated at its Vehicle Research and Test Center. There are two objectives of this study. Since the foam in the TRL upper legform impactor has a history of sensitivity to humidity, the first evaluates the impactor under different humidity conditions. Vehicle tests were also carried out to see if the upper legform sensitivity to humidity carries over to vehicle tests. The second objective evaluated sensitivity to vehicle bumper design, repeatability, reproducibility, durability, and biofidelity.

DC Charging Safety Evaluation Procedure Development, Validation, and Assessment; and Preliminary Draft AC Charging Evaluation Procedure

This report describes and validates a holistic collection of test procedures assessing safety hazards to electric vehicles while being charged. If not properly protected and controlled, vehicle charging using either AC or DC current can introduce hazards ranging from high-voltage exposure to the vehicle or damage to the battery. The tests procedures in this report have been independently developed using commonly accepted single-point failure modes and hazards identified in 24 separate FMEAs related to electric vehicle applications of Li-ion battery technology and the system’s ability to effectively detect and mitigate safety-relevant occurrences during charging.

Ford Safety Performance of Rechargeable Energy Storage Systems

This study of rechargeable energy storage systems (RESS) in electrified vehicles defines lithium ion battery performance-based safety metrics, safety performance test procedures, and metrics conducted at the vehicle level. Research involved identification, review, and assessment of existing test procedures to determine adequacy and applicability to this research. To define priority failure events in the RESS, a fault tree analysis (FTA) was conducted that lead to the identification of crush, overcharge and short circuits as principle fault mechanisms, and provided understanding of the key faults within those failure modes.  The testing included data acquisition for voltage, current, and temperature supported with photographic and video files. The results are reproducible and repeatable test procedures indicating threshold levels that should not be exceeded in a vehicle fault event.

Front Seat Modeling in Rear Impact Crashes: Development of a Detailed Finite-Element Model for Seat Back Strength Requirements

NHTSA contracted EDAG, Inc., to re-examine feasibility of increasing the seat back strength by developing a detailed finite-element model of a current vehicle front seat design that can be used with existing biofidelic rear impact dummies to study seat performance in rear impact crashes. Results are the finite-element models of a 2014 Honda Accord mid-size sedan representing typical front seats. Two front seat models were developed using LS-DYNA simulation code, a manually operated seat and a power-operated seat, both capable of simulating occupant kinematics and injury performance measures in rear impact and capable of responding to incremental impulses spanning from 17 km/hr up to 40 km/hr.

Rear Amber Turn Signal Lamps Confirmation Test - Example Measurements

This report summarizes an evaluated draft test procedure for confirming amber rear turn signal lamp color. It adapts existing test procedures from FMVSS No. 108, Lamps, reflective devices, and associated equipment, to accommodate testing the lamps as installed on the vehicle. Four vehicles were tested. Overall, the test procedure was found to be easy to carry out and effective in determining turn signal lamp color.

Traffic Jam Assist Test Development Considerations

This report summarizes three preliminary Traffic Jam Assist (TJA) test scenarios, discusses test results of three commercially available vehicles equipped with TJA, assesses real-world scenarios, and considers performance capabilities of the TJA systems presently available. The first scenario involved a lead vehicle accelerating to the desired speed and braking to a stop. In the second scenario, a lead vehicle abruptly changed lanes to suddenly reveal a stopped vehicle. The final scenario used a cut-in and deceleration maneuver performed at close range to the subject vehicle. The three vehicles tested were a 2017 Mercedes E300, a 2017 Tesla Model S 90D, and a 2017 BMW 540i xDrive. 

Pedestrian Protection – Assessment of the U.S. Vehicle Fleet

This study evaluated pedestrian protection in the U.S. vehicle fleet using established Euro NCAP pedestrian test procedures including lower legform and upper legform impacts to the front end of the vehicle and headform impacts to the hood and windshield. In general, global vehicles (models that include a U.S. variant and a European variant of the same vehicle) offer more pedestrian safety than vehicles marketed primarily in the U.S.   The second objective assessed equivalency of pedestrian protection in U.S. versus European variants of the same vehicle model. U.S. variants performed worse than European variants in the lower legform assessment, but no worse than (and perhaps slightly better than) non-global “passenger cars.” In upper legform tests, the global “passenger cars” perform very well, with U.S. and European variants performing equally as well.