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Vehicle rollovers are one of the more severe crash modes in the US - accounting for 32% of all passenger vehicle occupant fatalities annually. One design enhancement to help prevent rollovers is Electronic Stability Control (ESC) which can reduce loss of control and thus has great promise to enhance vehicle safety. The objectives of this research were (1) to estimate the effectiveness of ESC in reducing the number of rollover crashes and (2) to identify cases in which ESC did not prevent the rollover to potentially advance additional ESC development. All passenger vehicles and light trucks and vans that experienced a rollover from 2006 to 2015 in the National Automotive Sampling System Crashworthiness Database System (NASS/CDS) were analyzed. Each rollover was assigned a crash scenario based on the crash type, pre-crash maneuver, and pre-crash events.

This study used finite element (FE) simulations to analyze the injury mechanisms of driver spine fracture during frontal crashes in the World Endurance Championship (WEC) series and possible countermeasures are suggested to help reduce spine fracture risk. This FE model incorporated the Total Human Model for Safety (THUMS) scaled to a driver, a model of the detailed racecar cockpit and a model of the seat/restraint systems. A frontal impact deceleration pulse was applied to the cockpit model. In the simulation, the driver chest moved forward under the shoulder belt and the pelvis was restrained by the crotch belt and the leg hump. The simulation predicted spine fracture at T11 and T12. It was found that a combination of axial compression force and bending moment at the spine caused the fractures. The axial compression force and bending moment were generated by the shoulder belt down force as the driver’s chest moved forward.

Lower extremity injuries in frontal automotive crashes usually occur with footwell intrusion where both the knee and foot are constrained. In order to identify factors associated with tibial shaft injury, a series of numerical simulations were conducted using a finite element model of the whole human body. These simulations demonstrated that tibial mid-shaft injuries in frontal crashes could be caused by an abrupt change in velocity and a high rate of footwell intrusion.

JAMA (Japan Automobile Manufactures Association, Inc.)'s guideline for car navigation systems is being decided on displayed the amount of information while driving. The position of a display and the estimated equation, which could be applied from a passenger car to a heavy truck, was studied. The evaluation index was the distance which drivers could become aware of a preceding vehicle by their peripheral vision, because car accidents while drivers glance at an in- vehicle display are almost the rear end collisions. As the results, the lower limit of a position of an in-vehicle display for a passenger car was 30 degrees, and a heavy truck was 46 degrees.

In the present investigation, a numerical model of side impact dummy (DOT-SID) is developed using TNO's MADYMO-3D multi-body features. During the model construction phases, relevant dummy components are individually modeled and are verified against empirical test results. The completed DOT-SID model is then integrated into a padded impactor model to simulate secondary-impact. Computations are run for several input force-deflection distributions, in conjunction with other parameters. From the results, occupant responses to various thoracic input are quantitatively sought, and the effectiveness of the MADYMO DOT-SID model as a vehicle development tool is assessed.

A new automotive interior component material, TSOP-5 has been developed by refining the technology utilized to develop TSOP-1, the high modulus and high flow material for bumper covers. This new interior component material has excellent molding capability (MI=30dg/min.) yet still maintains high impact resistance which enables the material to be used in areas such as the dash board as well as trim covers requiring to meet the FMVSS 214, the new side impact regulation or the FMVSS 201, the new soft upper trim regulation.

A cooperative research program has been completed evaluating the relative impact of fuel composition and engine design features on the emissions and fuel economy of a Toyota light-duty diesel truck. The fuel set was blended from commercially available refinery stocks and consisted of eight fuels with independently varying 10% and 90% distillation temperatures and aromatic content. The engine design variables included two compression ratios and three injector types with different fuel flow characteristics, and three injection timings. The main fuel effects observed were increasing hydrocarbon and particulate emissions with increasing aromatic content and, to a much lesser degree, increasing emissions with increasing 10% and 90% point. Changing from the standard fuel injectors to the reference injectors, which had both a higher nozzle opening pressure and a higher initial fuel flow rate, resulted in a substantial reduction in all emissions and improvements in fuel economy.

This paper describes a three-dimensional crash simulation program code-named ‘CRASH’ and its evaluation. This program predicts body deformation behavior of an automotive vehicle in a crash. In the program the body is represented by a structure consisting of beam elements. The inelastic deformation is calculated with the simplified constitutive equation using the yielding function. Reduced load carrying capacities due to local deformations are considered by means of representative static load-deformation curves obtained by experiments. Deformation behavior of the structural members with the above properties are analyzed with direct integration scheme taking the strain rate effects into consideration. Large displacements of structural members are also accurately calculated with the coordinate transformation matrices taking account of the finite rotations.