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As part of the International Lubricant Standardization and Approval Committee's (ILSAC) goal of developing a global automatic transmission fluid (ATF) specification, members have been evaluating test methods that are currently used by various automotive manufacturers for qualifying ATF for use in their respective transmissions. This report deals with comparing test methods used for determining torque capacity in friction systems (shifting clutches). Three test methods were compared, the Plate Friction Test from the General Motors DEXRON®-III Specification, the Friction Durability Test from the Ford MERCON® Specification, and the Japanese Automotive Manufacturers Association Friction Test - JASO Method 348-95. Eight different fluids were evaluated. Friction parameters used in the comparison were breakaway friction, dynamic friction torque at midpoint and the end of engagement, and the ratio of end torque to midpoint torque.

One of the primary reasons that FMVSS 111 currently requires flat rearview mirrors as original equipment on the driver's side of passenger cars is a concern that convex mirrors might reduce safety by causing drivers to overestimate the distances to following vehicles. Several previous studies of the effects of convex rearview mirrors have indicated that they do cause overestimations of distance, but of much lower magnitude than would be expected based on the mirrors' levels of image minification and the resulting visual angles experienced by drivers. Previous studies have investigated mirrors with radiuses of curvature up to 2000 mm. The present empirical study was designed to investigate the effects of mirrors with larger radiuses (up to 8900 mm). Such results are of interest because of the possible use of large radiuses in some aspheric mirror designs, and because of the information they provide about the basic mechanisms by which convex mirrors affect distance perception.

A hybrid Finite Element Analysis (hybrid FEA) formulation has been developed in the past for computing the mid-frequency vibration of systems that contain one type of energy. The hybrid FEA is based on characterizing as long members in a system all the members that contain a large number of wavelengths within their dimension. All the remaining members are considered as short. The Energy Finite Element Analysis (EFEA) is employed for modeling the behavior of the long members, while the conventional FEA method is utilized for modeling the short members. In this paper the hybrid FEA formulation is extended to plate structures that are spot-welded to a frame comprised by tubular members. The new formulation is validated by comparing the hybrid FEA solution to results produced by very dense conventional FEA models in the mid-frequency range.

A new development in the area of the hybrid Finite Element Analysis (hybrid FEA) is presented. The hybrid FEA method combines the conventional FEA method with energy FEA (EFEA) for analysis of systems that contain both flexible and stiff members, and is suitable for mid-frequency computations. A formulation for analyzing flexible plates spot-welded to stiff beams when the excitation is applied on the stiff members is developed. Conventional FEA models are employed for modeling the behavior of the stiff members in a system. Appropriate damping elements are introduced in the connections between stiff and flexible members in order to capture the presence of the flexible members during the analyses of the stiff ones.

This study was designed to provide photometric information about current European low-beam headlamps. The sample included 20 low-beam headlamps manufactured for use on the 20 best-selling passenger vehicles for calendar year 1999 in 17 European countries. These 20 vehicles represent 47% of all vehicles sold in these countries. The lamps were purchased directly from vehicle dealerships, and photometered in 0.25° steps from 45° left to 45° right, and from 5° down to 7° up. The photometric information for each lamp was weighted by 1999 sales figures for the corresponding vehicle. The results are presented both in tabular form for the 25th-percentile, the median (50th-percentile), and the 75th-percentile luminous intensities, as well as in graphical form (for the median luminous intensities).

Vehicle motions can adversely affect the ability of a driver or occupant to quickly and accurately push control buttons located in many advanced vehicle control, navigation and communications systems. A pilot study was conducted using the U.S. Army Tank Automotive and Armaments Command (TACOM) Ride Motion Simulator (RMS) to assess the effects of vertical ride motion on the kinematics of reaching. The RMS was programmed to produce 0.5 g and 0.8 g peak-to-peak sinusoidal inputs at the seat-sitter interface over a range of frequencies. Two participants performed seated reaching tasks to locations typical of in-vehicle controls under static conditions and with single-frequency inputs between 0 and 10 Hz. The participants also held terminal reach postures during 0.5 to 32 Hz sine sweeps. Reach kinematics were recorded using a 10-camera VICON motion capture system. The effects of vertical ride motion on movement time, accuracy, and subjective responses were assessed.

Rapid change is a way of life in Chrysler. Facing increasing competition, we realize that the traditional practices are no longer sufficient. Accordingly, a new process using simultaneous engineering (SE) teams in conjunction with reliability tools has been used to design and develop a new family of Chrysler engines. These SE teams include representatives from engine engineering, vehicle platform engineering, electrical engineering, manufacturing, reliability & service engineering, finance and suppliers. The SE teams maximize the use of up-front engineering tools, such as Finite Element Analysis (FEA), Digital Model Assembly (DMA), Variation Simulation Analysis (VSA) and Rapid Prototyping with StereoLithography (SLA), Laminated Object Manufacturing (LOM), etc. The new process combines these up-front engineering activities and the appropriate reliability testing as an integral part of the reliability growth process. It enhances the design decisions made with reliability.

Current automotive design practices related to driver visibility are based on static laboratory studies of mostly straight ahead viewing that were conducted by Meldrum and others beginning in 1962. These individual studies have never been replicated either in the lab or in actual driving situations to determine the validity of their procedures. After a thorough review of the literature related to driver eye location and a statistical analysis of previous static eye location data, an experimental design is proposed to determine dynamic eye location distribution characteristics. This design will provide information on: (a) the relationship of static anthropometric measurements to dynamic eye location; (b) the difference between dynamic on-the-road eye location versus static in-the-lab eye location distributions: (c) the effect of different types of vehicle seating package parameters on eye location; and, (d) a validation of previous static eye location studies.

In this paper, the available correlations proposed in the literature for the gas-side heat transfer in the intake and exhaust system of a spark-ignition internal combustion engine were surveyed. It was noticed that these only by empirically fitted constants. This similarity provided the impetus for the authors to explore if a universal correlation could be developed. Based on a scaling approach using microscales of turbulence, the authors have fixed the exponential factor on the Reynolds number and thus reduced the number of adjustable coefficients to just one; the latter can be determined from a least squares curve-fit of available experimental data. Using intake and exhaust side data, it was shown that the universal correlation The correlation coefficient of this proposed heat transfer model with all available experimental data is 0.845 for the intake side and 0.800 for the exhaust side.

A formulation that accounts for manufacturing variability in the analysis of structural/acoustic systems is presented. The methodology incorporates the concept of fast probability integration with finite element (FEA) and boundary element analysis (BEA) for producing the probabilistic acoustic response of a structural/acoustic system. The advanced mean value method is used for integrating the system probability density function. FEA and BEA are combined for producing the acoustic response that constitutes the performance function. The probabilistic acoustic response is calculated in terms of a cumulative distribution function. The new methodology is used to illustrate the difference between the results from a probabilistic analysis that accounts for manufacturing uncertainty, and an equivalent deterministic simulation through applications. The probabilistic computations are validated by comparison to Monte Carlo simulations.

An advanced three-way converter system with significant improvements in light-off performance, conversion efficiency, thermal stability and physical durability at high operating temperature is described. The converter system is comprised of a light-weight ceramic substrate with high surface area triangular cell structure, a new catalyst formulation with enhanced thermal stability and good substrate compatibility, and a durable packaging design which together lead to consistent improvements in high temperature performance and durability. Experimental data including FTP performance, canning trials, and high temperature vibration and thermal shock tests for both the advanced and standard three-way converter systems are presented.

Automotive exhaust emission regulations are becoming progressively stricter due to increasing awareness of the hazardous effects of exhaust emissions. The main challenge to meet the regulations is to reduce the emissions during cold starts, because catalytic converters are ineffective until they reach a light-off temperature. It has been found that 50% to 80% of the regulated hydrocarbon and carbon monoxide emissions are emitted from the automotive tailpipe during the cold starts. Therefore, understanding the catalytic converter characteristics during the cold starts is important for the improvement of the cold start performances This paper describes a mathematical model that simulates transient performances of catalytic converters. The model considers the effect of heat transfer and catalyst chemical reactions as exhaust gases flow through the catalyst. The heat transfer model includes the heat loss by conduction and convection.

A hybrid finite element formulation for analyzing flexible plates connected to stiff frame was developed. The excitation was considered to be applied on the stiff members. Conventional FEA models were employed for modeling the behavior of the stiff members in a system. Appropriate damping elements were introduced in the connections between stiff and flexible members in order to capture the presence of the flexible members during the analyses of the stiff ones. Once the vibration of the stiff members and the amount of power dissipated at the damping elements was identified, an EFEA analysis was performed in order to determine the amount of vibrational energy in the flexible members. The hybrid FEA is applied to a Body-In-White (BIW). The results of the hybrid FEA are compared with results from very dense conventional finite element analyses.

This paper assesses the potential for car and light truck fuel economy improvements by 2010-15. We examine a range of refinements to body systems and powertrain, reflecting current best practice as well as emerging technologies such as advanced engine and transmission, lightweight materials, integrated starter-generators, and hybrid drive. Engine options are restricted to those already known to meet upcoming California emissions standards. Our approach is to apply a state-of-art vehicle system simulation model to assess vehicle fuel economy gains and performance levels. We select a set of baseline vehicles representing five major classes - Small and Standard Cars, Pickup Trucks, SUVs and Minivans - and analyze design changes likely to be commercially viable within the coming decade. Results vary by vehicle type.

Five small two-stroke engine designs were tested at different air/fuel ratios, under steady state and transient cycles. The effects of combustion chamber design, carburetor design, lean burning, and fuel composition on performance, hydrocarbon and carbon monoxide emissions were studied. All tested engines had been designed to run richer than stoichiometric in order to obtain satisfactory cooling and higher power. While hydrocarbon and carbon monoxide emissions could be greatly reduced with lean burning, engine durability would be worsened. However, it was shown that the use of a catalytic converter with acceptably lean combustion was an effective method of reducing emissions. Replacing carburetion with in-cylinder fuel injection in one of the engines resulted in a significant reduction of hydrocarbon and carbon monoxide emissions.

The transient cone angle of a pressure swirl spray from an injector for gasoline direct injection engines was measured from 2D Mie scattering images. Iso-octane was used as the fluid that was delivered at room temperature for two different static pressures, 5MPa and 8.5MPa. The iso-octane was injected into a chamber at room temperature and ambient pressure. After a rapid initial increase, the cone angle oscillates before stabilizing to a steady-state value very close to the nominal cone angle. The period of the oscillation was found to correlate well with oscillations measured in the fuel line pressure.

A combination of imaging techniques for investigations of highly transient processes and cyclic variations in internal combustion engines is presented. The single high-speed camera setup uses a CMOS camera combined with a two-stage image-intensifier and two excimer lasers. Fuel mixing, ignition and combustion were monitored via planar laser induced fluorescence imaging of toluene as a tracer that was added to iso-octane in combination with the simultaneous recording of light emission from the spark plasma and OH* chemiluminescence of the developing flame. Image frame rates of 12 kHz for hundreds of cycles were achieved. Application to misfire events in a spray-guided gasoline direct-injection engine is described to illustrate the merits of the technique.

The Federal Motor Vehicle Safety Standards currently require driver-side rearview mirrors to be flat. For rearview mirrors of typical size, this requirement normally results in a blind zone on the driver side that is large enough to conceal an average size passenger car. In recent years a number of studies have suggested that nonplanar rearview mirrors may be an effective solution to this problem. This paper reviews the evidence on possible effectiveness of nonplanar mirrors, assesses the strength of that evidence, and makes tentative recommendations. The main conclusion is that the use of nonplanar mirrors would probably result in a net gain in safety, but that the effectiveness of the mirrors is likely to depend on details of how they are implemented. Issues that should be resolved by additional research (some of which is already underway) are: (1) How would U.S. drivers respond to a mixed fleet of vehicles, some of which had flat mirrors and some of which had nonplanar mirrors?

The target cascading methodology is applied to the conceptual design of an advanced heavy tactical truck. Two levels are defined: an integrated truck model is represented at the top (vehicle) level and four independent suspension arms are represented at the lower (system) level. Necessary analysis models are developed, and design problems are formulated and solved iteratively at both levels. Hence, vehicle design variables and system specifications are determined in a consistent manner. Two different target sets and two different propulsion systems are considered. Trade-offs between conflicting targets are identified. It is demonstrated that target cascading can be useful in avoiding costly design iterations late in the product development process.

In this paper, an analytical method is proposed for determining the stress distributions in steering knuckle/tapered stud assemblies. The method is based on solutions of the plane stress thick cylinder interference fit problem with modifications to account for the effects of stud taper and dissimilar component materials. The analytical solutions are applied to knuckle/tapered stud assemblies. The results from the analytical solutions are compared to those from a finite element analysis. It is shown that the analytical and FEA results are in good agreement for several load and frictional conditions, and the hoop and radial stress solutions presented in this paper are good engineering solutions to the knuckle/tapered stud problem where the draw distance is provided.