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In the United States, there are two leading frontal crash consumer information rating systems for light vehicles. The first is the National Highway Traffic Safety Administration's New Car Assessment Program (NCAP). The second rating system comes from the Insurance Institute for Highway Safety (NHS). For vehicle manufacturers, performing well in these rating systems has become an integral part of their safety program and the design of their vehicles. However, there has been much debate on the impact of these rating systems on vehicle design characteristics, specifically, their effects on frontal stiffness to improve these ratings. Increased frontal stiffness in light trucks and vans (LTVs) has been shown to increase LTV aggressivity in LTV-car crashes, which is a concern. This paper focuses on how frontal stiffness relates to occupant compartment intrusion by vehicle type.

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.

NHTSA has recently released the documentation for manufacture and use of the Thor-Lx Hybrid III retrofit (Thor-Lx/HIIIr), an advanced lower extremity device that fits on the Hybrid III 50th percentile male dummy at the distal femur. In order to compare the response of the Thor-Lx/HIIIr and the Denton leg in the vehicle crash environment, NHTSA conducted a series of vehicle crash tests where 40 percent of the vehicle’s frontal structure along the driver’s side engaged the EU deformable barrier. The test series consisted of 4 pairs of crash tests using a belted Hybrid III 50th percentile adult male dummy in the driver’s position. Pairs of tests were conducted under identical crash conditions using the same vehicle make, model, and model year with the Denton legs on the dummy in one test and the Thor-Lx/HIIIr legs on the dummy in the other test. This paper presents a detailed analysis of the responses of the Hybrid III dummy and the two types of legs in the paired crash tests.

Globally, many jurisdictions are working toward greenhouse gas (GHG) emissions standards for medium- and heavy-duty vehicles that will take effect in the next decade and require GHG reductions of up to 25% from 2017 legislated levels. While diesel engines will require increasingly complex improvements, high pressure direct injection (HPDI) of natural gas can provide GHG reductions of approximately 20% (75% or more with renewable natural gas / bio-methane) while preserving the same power density, torque and performance as diesel. This paper will provide an overview of the improvements in the Westport™ HPDI 2.0 components as well as performance and emissions results demonstrated to-date. The potential and challenges of higher injection pressures will be explored while also investigating sources of and methods to eliminate methane venting on the vehicle.

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.

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.