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The objective of this paper is to describe the general methodology used by NHTSA to perform cost-effectiveness analyses and cost-benefit analyses. This general method will then be directed towards how one could analyze fire countermeasures, providing two analyses as examples. First, for crash related fires, NHTSA's 2003 analysis on fuel tank integrity will be used. Second, for non-crash related fires, NHTSA's 2001 analysis of radiator caps will be used. The paper will describe what data sources were used to determine the target population, the severity of injuries, the costs of burns by injury severity, the cost of the fire countermeasures, etc. While not analyzing any specific fire countermeasure, the methodology will be described in enough detail that others could potentially follow the methodology and make estimates for their own purposes.

In September 2009 the National Highway Traffic Safety Administration (NHTSA) published a report that investigated the incidence of fatalities to belted non-ejected occupants in frontal crashes involving late-model vehicles. The report concluded that after exceedingly severe crashes, the largest number of fatalities occurred in crashes involving poor structural engagement between the vehicle and its collision partner, present in crashes characterized as corner impacts, oblique crashes, impacts with narrow objects, and heavy vehicle underrides. By contrast, few if any of these 122 fatal crashes were full-frontal or offset-frontal impacts with good structural engagement, excepting crashes that were of extreme severity or the occupants that were exceptionally vulnerable. The intent of this research program is to develop a test protocol that replicates real-world injury potential in small overlap impacts (SOI) and oblique offset impacts (Oblique) in motor vehicle crashes.

The purpose of the study was to distinguish the role of vehicle structure in frontal impacts in published coded National Automotive Sampling System (NASS-CDS) data. The criteria used: Collision Deformation Classification (CDC) coding rules, crush profile locator data and the projected location of longitudinal structural members in models of vehicle class sizes used by NASS-CDS. Two classifiers were developed to augment the CDC system. The Coincidence classifier indicates the relationship between the quadrant of the clock face the crash vector originates in and the aspect of the end plane the center of damage is located. It has three values: Linear (12 o'clock impacts) Consistent and Variant ("oblique" Principal Directions of Force or PDOFs). The second classifier indicates the number of longitudinal members engaged: 0, 1 or 2. NASS-CDS data for sample years 2005 to 2009 was filtered for occupants involved in impacts with the highest ranked speed change assigned to the front-end plane.

Objectives. Examination of head injuries in the Pedestrian Crash Data Study (PCDS) indicates that many pedestrian head injuries are induced by a combination of head translation and rotation. The Simulated Injury Monitor (SIMon) is a computer algorithm that calculates both translational and rotational motion parameters relatable head injury. The objective of this study is to examine how effectively HIC and three SIMon correlates predict the presence of either their associated head injury or any serious head injury in pedestrian collisions. Methods. Ten reconstructions of actual pedestrian crashes documented by the PCDS were conducted using a combination of MADYMO simulations and experimental headform impacts. Linear accelerations of the head corresponding to a nine-accelerometer array were calculated within the MADYMO model's head simulation.

There are a number of characteristics that are unique to light emitting diodes (LEDs) that make it difficult to ascertain whether a motor vehicle lamp using them as light sources is in compliance with certain Federal and State regulations. The vast majority of these regulations were written for incandescent light sources and should be examined for possible changes to accommodate LEDs. The advantages of using LEDs instead of incandescent sources include longer life, faster illumination time, and lower energy use. Because of these factors, they are becoming more prevalent in vehicle lighting. The following factors should be addressed so as not to impede their increasing use.

The purpose of the study was to identify all small overlap impacts using published coded NASS-CDS data. Three sets of criteria were used: CDC measurements; crush profiles for frontal impacts; and crush profiles for oblique side impacts to the fender component. All criteria were applied to passenger and non-passenger cars and their different vehicle class sizes. Data were analyzed based on fatalities and different levels of MAIS trauma. The overall data set based on CDC codes for 2005 to 2008 NASS-CDS data had 9,206 MAIS=0; 13,522 MAIS=1-2; 3,600 MAIS=3-6; 1,092 MAIS=7; and 961 fatal cases. For the weighted ensemble, these data were: 5,800,295; 4,324,773; 269,042; 219,481; and 44,906 cases, respectively. However, these cases reduced to 1071, 1468, 364, 82, and 87 raw cases with the application of the CDC criteria for frontal impacts.

National Highway Traffic Safety Administration (NHTSA) has developed an Oblique Offset Moving Deformable Barrier test procedure. For this test procedure to be viable, it must be repeatable within each test facility and it must be reproducible between test facilities. Three tests of a single vehicle model were conducted at three different test facilities, a total of nine tests, to evaluate repeatability and reproducibility. The responses of the vehicle and its occupants were evaluated using three different methodologies to quantify the repeatability within a single test facility and reproducibility among the three test facilities. The first two methods evaluated the time-history of the measured data and the third method only used the peak values. Overall, this test series demonstrated repeatable and reproducible results for the OMDB, vehicle, and driver occupant in the oblique offset test procedure. The method using only the peak values indicates more variability.

The study reports on the results of frontal collisions with 16 cadavers and two Hybrid III dummies with impact velocities of 48 km/h to 55 km/h and a mean sled deceleration of 17 g; mounted to the sled was the front part of a passenger compartment. The cadavers were restrained in the driver position with either 3-point belts (6% and 16 % elongation) and/or air bag with knee bolster and one case was unrestrained. In most cases, both a 12-accelerometer thoracic array and 2 chest bands were employed. In some cases the acceleration at Th6 was measured. The cadavers were autopsied and the injury severity was rated according to the AIS 90. Maximum resultant Th1, Th6, and Th12 accelerations or sternum accelerations in x-direction ranged from 35g to 78g when using 3-point belts and produced injuries ranging from a few rib fractures to unstable chest wall (flail chest).

This paper reports the results of one of the tasks addressed in a coordinated NHTSA/MVMA side impact test procedure development program: the identification of specific tests which should be able to discriminate among vehicle designs having a significant effect on side impact injuries. Component and full vehicle crash tests addressing impacts between specific occupant body parts and vehicle regions are recommended for development. Advantages and disadvantages of component vs. full vehicle tests are discussed and areas needing further research to support side impact test development are recommended.

To improve the biofidelity of the currently available Hybrid III 10-year-old (HIII-10C) Anthropomorphic Test Device (ATD), the National Highway Traffic Safety Administration (NHTSA) has developed the Large Omnidirectional Child (LODC) ATD. The LODC head is a redesigned HIII-10C head with mass properties and modified skin material required to match pediatric biomechanical impact response targets from the literature. A dynamic, nonlinear finite element (FE) model of the LODC head has been developed using the mesh generating tool Hypermesh based on the three-dimensional CAD model. The material data, contact definitions, and initial conditions are defined in LS-PrePost and converted to LS-Dyna solver input format. The aluminum head skull is stiff relative to head flesh material and was thus modeled as a rigid material. For the actual LODC, the head flesh is form fit onto the skull and held in place through contact friction.

Testing vision-based advanced driver assistance systems (ADAS) in a Camera-in-the-Loop (CiL) bench setup, where external visual inputs are used to stimulate the system, provides an opportunity to experiment with a wide variety of test scenarios, different types of vehicle actors, vulnerable road users, and weather conditions that may be difficult to replicate in the real world. In addition, once the CiL bench is setup and operating, experiments can be performed in less time when compared to track testing alternatives. In order to better quantify normal operating zones, track testing results were used to identify behavior corridors via a statistical methodology. After determining normal operational variability via track testing of baseline stationary surrogate vehicle and pedestrian scenarios, these operating zones were applied to screen-based testing in a CiL test setup to determine particularly challenging scenarios which might benefit from replication in a track testing environment.

Finite element (FE) modeling is becoming an integral approach to the study of crashworthiness of vehicle structures and occupant interaction with the structure. Crashworthiness assessment of a vehicle using numerical techniques necessitates the development of not only an accurate and representative vehicle model, but also a robust occupant model. This paper describes the development of mathematical models to perform the complete side impact simulation. The fully developed model can be used to evaluate occupant compartment intrusion and to assess occupant protection countermeasures in various side impact scenarios. A baseline finite element model of the side impact dummy (SID) used in the United States safety regulation, FMVSS 214, Side Impact Protection [7], was refined and calibrated using dynamic material and sub-system test data. Lower extremity geometry was reverse engineered and suitable material models and joints were incorporated in the revised model.

This paper describes the design and development of an advanced instrumentation Moving Deformable Barrier (MDB) for use in research crash testing to address vehicle aggressitivity and compatability issues. The instrumented MDB design is an adaptation of the current Federal Motor Vehicle Safety Standard (FMVSS No. 214) MDB design and duplicates as closely as possible its physical and dynamic specifications. Forty-four equally spaced low weight triaxial load cells are placed behind the main body of the aluminum honeycomb structure. In addition, an equal number of string potentiometers are placed in the rear of the cart to measure the honeycomb crush. The triaxial load cells were specially designed to measure forces in both the longitudinal and shear directions. During the initial design stage, the number of load cells, their weight, placement, type, durability and measuring capacity were considered.

Posterior cruciate ligament (PCL) injuries, although rarely life threatening, affect the quality of life of the person who sustains the injury. The PCL is the primary restraint to posterior tibial translation and can be injured when the tibia moves posteriorly relative to the femur. This type of injury is common in frontal crashes where the tibia may impact the dashboard or steering column. To quantify what happens during dynamic loading of the tibial plateau, isolated cadaveric lower limbs (n = 14) were impacted at dynamic rates with a linear pneumatic ram. During the testing, a static load was applied to the quadriceps tendon to simulate active musculature. Forces as well as the stretch of the PCL were measured. The most common injuries were tibia fractures and PCL tears. The stiffness for the tests at impact velocities of 1.4 and 2.9 m/s were on average 120 N/mm and 141N/mm, respectively. A trend towards increasing femur force with increasing velocity was found.

Sloped medians provide a run-off area for errant vehicles so that they can be safely stopped off-road with or without barriers placed in the sloped median. However, in order to optimize the design of sloped medians and the containment barriers, it is essential to accurately model the behavior of vehicles on such sloped terrain surfaces. In this study, models of a vehicle fleet comprising a small sedan and a pickup truck and sloped terrain surface are developed in CarSim™ to simulate errant vehicle behavior on sloped median. Full-scale crash tests were conducted using the vehicle fleet driven across a 9.754 meters wide median with a 6:1 slope at speeds ranging from 30 to 70 km/h. Measured data such as the lateral accelerations of the vehicle as well as chassis rotations (roll and pitch) were synchronized with the vehicle motion obtained from the video data.

NHTSA has developed two different moving deformable barrier-to-vehicle test procedures to assess the vehicle and occupant response in narrow overlap motor vehicle crashes. An assessment of test repeatability is one of the requirements necessary to accept the test procedure as viable. Previous methodologies, coefficient of variation (CV) and similarity analysis were developed to assess the repeatability of vehicle and occupant response in motor vehicle crash tests for full frontal and 40% overlap tests procedures. These will be used for this assessment. Three repeat tests were performed in each test procedure, with all other factors held constant: vehicles of the same make, model, and model year; moving deformable barriers of the same mass, velocity, and barrier face properties; and the same occupant - a THOR 50th percentile adult male in the driver's seat.

In order to validate the operation of advanced driver assistance systems (ADAS), tests must be performed that assess the performance of the system in response to different scenarios. Some of these systems are designed for crash-imminent situations, and safely testing them requires large stretches of controlled pavement, expensive surrogate targets, and a fully functional vehicle. As a possible more-manageable alternative to testing the full vehicle in these situations, this study sought to explore whether these systems could be isolated, and tests could be performed on a bench via a hardware-in-the-loop methodology. For camera systems, these benches are called Camera-in-the-Loop (CiL) systems and involve presenting visual stimuli to the device via an external input.

The Test Device for Human Occupant Restraint (THOR) is an advanced crash test dummy designed for frontal impact. Originally released in a 50th percentile male version (THOR-50M), a female 5th version (THOR-05F) was prototyped in 2017 (Wang et al., 2017) and compared with biofidelity sub-system tests (Wang et al., 2018). The same year, Trosseille et al. (2018) published response corridors using nine 5th percentile female Post Mortem Human Subjects (PMHS) tested in three sled configurations, including both submarining and non-submarining cases. The goal of this paper is to provide an initial evaluation of the THOR-05F biofidelity in a full-scale sled test, by comparing its response with the PMHS corridors published by Trosseille et al. (2018). Significant similarities between PMHS and THOR-05F were observed: as in Trosseille et al. (2018), the THOR-05F did not submarine in configuration 1, and submarined in configurations 2 and 3.

Very little experimental research has focused on the kinematics, dynamics, and injuries of rear-seated occupants. This study seeks to develop a baseline response for rear-seated post mortem human surrogates (PMHS) in frontal crashes. Three PMHS sled tests were performed in a sled buck designed to represent the interior rear-seat compartment of a contemporary midsized sedan. All occupants were positioned in the right-rear passenger seat and subjected to simulated frontal crashes with an impact speed of 48 km/h. The subjects were restrained by a standard, rear seat, 3-point seat belt. The response of each subject was evaluated in terms of whole-body kinematics, dynamics, and injury. All the PMHS experienced excessive forward translation of the pelvis resulting in a backward rotation of the torso at the time of maximum forward excursion.

The National Highway Traffic Safety Administration has performed research investigating the Test Device for Human Occupant Restraint 50th male (THOR-50M) response in Oblique crash tests. This research is being expanded to investigate THOR-50M in the driver position in a 56 km/h frontal impact crash. Hybrid III 5th percentile adult female (AF05) anthropomorphic test devices (ATDs) were used in this testing to evaluate the RibEye Deflection Measurement System. The AF05 ATDs were positioned in the right front passenger and right rear passenger seating positions. For the right front passenger, the New Car Assessment Procedure (NCAP) seating procedure was used, except the seat fore-aft position was set to mid-track. For the right rear passenger, the seating followed the FMVSS No. 214 Side Impact Compliance Test Procedure. The NCAP frontal impact test procedure was followed with additional vehicle instrumentation and pre/post-test measurements.