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The Multi Material Lightweight Vehicle (MMLV) developed by Magna International and Ford Motor Company is a result of a US Department of Energy project DE-EE0005574. The project demonstrates the lightweighting potential of a five passenger sedan, while maintaining vehicle performance and occupant safety. Prototype vehicles were manufactured and limited full vehicle testing was conducted. The MMLV vehicle design, comprised of commercially available materials and production processes, achieved a 364kg (23.5%) full vehicle mass reduction, enabling the application of a 1.0-liter three-cylinder engine resulting in a significant environmental benefit and fuel reduction. The three key requirements of structural performance evaluation for vehicle development are NVH, durability and safety.

Sampling-based methods are general but time consuming for solving a Reliability-Based Design Optimization (RBDO) problem. In order to alleviate the computation burden, score function together with the Monte Carlo method was used to compute the stochastic sensitivities of reliability functions. In literature, re-weighting schemes were shown to converge faster than the regular Monte Carlo method. In this paper, a reweighting scheme together with score function is employed to perform sampling-based stochastic sensitivity analysis to improve the computational efficiency and accuracy. An analytical example is used to show the advantages of the proposed method. Comparisons to the conventional methods are made and discussed. Two RBDO problems are solved to demonstrate the use of the proposed method.

Incremental Sheet Forming (ISF) is an emerging sheet metal prototyping technology where a part is formed as one or more stylus tools are moving in a pre-determined path and deforming the sheet metal locally while the sheet blank is clamped along its periphery. A deformation analysis of incremental forming process is presented in this paper. The analysis includes the development of an analytical model for strain distributions based on part geometry and tool paths; and numerical simulations of the forming process with LS-DYNA. A skew cone is constructed and used as an example for the study. Analytical and numerical results are compared, and excellent correlations are found. It is demonstrated that the analytical model developed in this paper is reliable and efficient in the prediction of strain distributions for incremental forming process.

The integration of a HIL system involves many software and hardware elements. During the integration process, various errors may occur. In this paper, the Design For Six Sigma (DFSS) methodology is applied to develop an integration process for a generic type of HIL system. The development follows the DCOV (Design, Characterize, Optimize and Verify) four-phase approach. The result is an efficient process proven to meet the customer's needs, reduce integration errors and deliver a high quality HIL system within less time.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)/coir fiber composites were prepared via both conventional and microcellular injection-molding processes. The surface of the hydrophilic coir fiber was modified by alkali and silane-treatment to improve its adhesion with PHBV. The morphology, thermal, and mechanical properties were investigated. The addition of coir fiber (treated and untreated) reduced cell size and increased cell density. Further decrease in cell size and increase in cell density were observed for treated fibers compared with PHBV/untreated fiber composites. Mechanical properties such as specific toughness and strain-at-break improved for both solid and microcellular specimens with the addition of coir fibers (both treated and untreated); however, the specific modulus remained essentially the same statistically while the specific strength decreased slightly.

Design for Six Sigma (DFSS) has evolved as a worthy predecessor to the application of Six-Sigma principles to production, process control, and quality. At Lawrence Livermore National Laboratory (LLNL), we are exploring the interrelation of our current research, development, and design safety standards as they would relate to the principles of DFSS and Six-Sigma. We have had success in prioritization of research and design using a quantitative scalar metric for value, so we further explore the use of scalar metrics to represent the outcome of our use of the DFSS process. We use the design of an automotive component as an example of combining DFSS metrics into a scalar decision quantity. We then extend this concept to a high-priority, personnel safety example representing work that is toward the mature end of DFSS, and begins the transition into Six-Sigma for safety assessments in a production process.

This paper describes the steps utilized in the development of the Flex Fuel program by the Ford South America Product Development team to implement a reliability plan. A reliability plan, understood as series of tools to avoid failure mode occurrence, is particularly important when introducing a new technology. Robustness, as the ability of a system to perform its intended function in the presence of variable operational conditions, is contained in the reliability concept and is a key aspect of this plan. Several factors that could affect the vehicle performance were listed, classified and prioritized in order to establish a preventive action plan. The tools were used first at the vehicle level, and then cascaded down to subsystem and component level. Also, with the results of this analysis, design verification methods were enhanced to capture real world usage conditions.

The objective was to engineer a world-class supercar body that faithfully reproduces the 2002 Concept and pays homage to the 1960's road racer. The car had to be designed, developed and launched in 24 months, while meeting tough requirements for function, weight, occupant package and aerodynamics. Challenging features such as the cantilevered door, “clamshell” engine decklid and a deeply contoured hood were to be included. This paper will discuss how a dedicated team of enthusiasts can have a flexible approach to the engineering process, material selections and manufacturing processes to achieve the designer's vision in 24 months (Figure 1).

The Vehicle Exhaust Emissions Simulator was developed to evaluate the performance of vehicle emissions sampling and analytical systems. The simulator produces a representative tailpipe volume flow rate containing up to five emission constituents, injected via mass flow controllers (MFCs). Eliminating the variability of test results associated with the vehicle, driver, and dynamometer makes the simulator an ideal quality control tool for use in commissioning new test cells, checking data correlation between test cells, and evaluating overall system performance. Earlier vehicle emissions simulators being used in the industry were primarily for checking Constant Volume Samplers (CVSs) and Bag Benches but they did not have the ability to properly simulate tailpipe volume.

Sliding door designs are applied to rear side doors on vans and other large vehicles with a trend towards dual sliding doors with power operation. It is beneficial for the vehicle user to reduce the weight of and space occupied by these doors. Alcoa, in conjunction with Ford, has developed a multi-product, multi-material-based solution, which significantly reduces the cost of an aluminum sliding door and provides both consumer delight and stamping-assembly plant benefits. The design was successfully demonstrated through a concept readiness/technology demonstration program.

A method to predict gap distribution, can deformation and mounting force of catalytic converter during assembling and operation cycles has been developed using ABAQUS contact algorithm with user subroutine for material properties. Inherent in the methodology is the constitutive model for both vermiculite mat and wire mesh mounting materials, which is able to describe their nonlinear and thermal behaviors and shows good agreement with test results. A design optimization procedure is presented to achieve uniform gap design of can and substrate. The technology will enable engineers to generate robust converter can designs, substrate shape and stamping tools for minimum manufacturing failure rate and maximum durability performance once a mounting material is selected.

A compact in-situ tensile stress fixture was designed for the study of the combined effects of stress and automotive environments on structural glass fiber-reinforced composite materials. With this fixture, a standardized 300 hour laboratory screening test was developed to compare the residual property loss of composite materials due to concurrent exposure to stress and environment. It is of great importance that the data gathered in the laboratory have correlation to on-vehicle (in-service) performance, and that both lab and real world data be taken with a test system (in-situ test fixtures) capable of providing accurate and consistent results under either test condition.

In design for durability, it is generally believed that a compressive mean stress is beneficial and a tensile mean stress is detrimental. Quantitatively the effect of mean stress on fatigue life however is still inconclusive and may very well depend on both the material used and the loading conditions. Over the years, many models have been proposed to help predict mean stress effects. For example, in the long life region, Goodman's formula is widely used, while the Smith-Watson-Topper damage parameter seems the most popular for use in computerized local strain based fatigue tools. In this paper, several frequently cited mean stress correction methods together with the most recent crack closure based method are compared in various ways. Particular emphasis is given to the effect of yield level mean stresses, which has been traditionally neglected but is of practical importance to the ground vehicle industry.

The Bag Mini-diluter (BMD) is a proportional exhaust sampling system that is being studied as an improved measurement system for ultra-low level vehicle exhaust emissions. The traditional method for sampling vehicle exhaust has been the constant volume sampler (CVS) technique. This method dilutes the entire exhaust output from the vehicle, meters the mixture, and then takes a proportional sample for measurement. In contrast, the Mini-diluter sampling method meters a small sample of raw exhaust, and then dilutes this sample to a fixed dilution ratio. This approach offers new opportunities to improve the quality of the sample measurement at very low levels, which will be crucial for accurate vehicle exhaust emission measurements on vehicles that meet the ULEV and SULEV standards. A number of test programs have compared the performance of the Mini-diluter to the CVS on vehicles certified to Tier 1 and LEV standards, and the results demonstrated favorable correlation.

Road to rig problems exist as long as vehicles are being tested. Many approaches and methods exist to produce test cycles for rigs or test tracks, in order to produce viable results for the generation of statements concerning such crucial aspects as durability and fuel consumption. Modern model strategies again demand shorter–than–ever development periods, whilst meeting better–than–ever the needs and demands of special target groups. Therefore, the testing methods must also be refined, in order to gain a closer correlation to the customer's vehicle deployment. The approach introduced here makes use of real–world customer data for obtaining a closer look at how the vehicle is used by different customer groups, in different countries. The data is collected by small and unobtrusive dataloggers installed in customer vehicles. As these customers are using their own vehicles in everyday life, being unaware of the acquisition process, a database of real customer usage is generated.

Since the door glass windows are used regularly, they have a great influence on the vehicle owner's perception of vehicle quality. Today's customers demand that moveable door window glass operates smoothly. Experimental methods have been developed to evaluate window glass smoothness and positional stability. This paper presents experimental results that quantify the chattering and positional stability of the window glass. For window glass smooth operation and tracking, the measurements were taken on glass chatter, glass velocity, motor current, motor voltage, and glass stall force. The change in glass position was measured on the vehicle during several stages of four poster durability testing to evaluate window glass positional stability during road induced vibrations. Using these experimental methods, the designers should be able to evaluate several window glass functional requirements and achieve cost/time savings.

Many studies suggest that lean-NOx SCR proceeds via oxidation of NO to NO2 by oxygen, followed by the reaction of the NO2 with hydrocarbons. On catalysts that are not very effective in catalyzing the equilibration of NO+O2 and NO2, the rate of N2 formation is substantially higher when the input NOx is NO2 instead of NO. The apparent bifunctional mechanism in the SCR of NOx has prompted the use of mechanically mixed catalyst components, in which one component is used to accelerate the oxidation of NO to NO2, and another component catalyzes the reaction between NO2 and the hydrocarbon. Catalysts that previously were regarded as inactive for NOx reduction could therefore become efficient when mixed with an oxidation catalyst. Preconverting NO to NO2 opens the opportunity for a wider range of SCR catalysts and perhaps improves the durability of these catalysts. This paper describes the use of a non-thermal plasma as an efficient means for selective partial oxidation of NO to NO2.

Obstacle detection technology has made significant progress in the last five years in the important product areas of quality, performance and affordability. Ford Motor Company's market research indicates that our customers are very interested in new safety features. Drivers consider obstacle detection and collision warning technology as the next breakthrough in safety technology. Ford recognizes the importance of moving from the collision mitigation to the collision avoidance paradigm. Fortunately, the first step in collision avoidance can be taken by equipping the vehicle with reliable and affordable obstacle detection sensors

The demand for highly flexible manipulation of plant growth generations, modification of specific plant processes, and genetically engineered crop varieties in a controlled environment has led to the development of a Commercial Plant Biotechnology Facility (CPBF). The CPBF is a quad-middeck locker playload to be mounted in the EXPRESS Rack that will be installed in the International Space Station (ISS). The CPBF integrates proven ASTROCULTURE” technologies, state-of-the-art control software, and fault tolerance and recovery technologies together to increase overall system efficiency, reliability, robustness, flexibility, and user friendliness. The CPBF provides a large plant growing volume for the support of commercial plant biotechnology studies and/or applications for long time plant research in a reduced gravity environment.

Students, as members of Team Paradigm, at the University of Wisconsin-Madison have designed a charge regulating, parallel hybrid electric Dodge Intrepid for the 1997 FutureCar Challenge (FCC97). The goals for the Wisconsin “FutureCow” are to achieve an equivalent fuel consumption of 26 km/L (62 mpg) and Tier 2 Federal Emissions levels while maintaining the full passenger/cargo room, appearance, and feel of a stock Intrepid. These goals are realized through drivetrain simulations, a refined vehicle control strategy, decreased engine emissions, and aggressive weight reduction. The vehicle development has been coupled with 8,000 km of reliability and performance testing to ensure Wisconsin will be a strong competitor at the FCC97.