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With the increasing number of air bags being used in vehicles there has been a corresponding increase in the number of occupants injured or even killed due to air bag deployment, particularly under out-of-position conditions. Current publications addressing the dangers of air bag deployment has led to worldwide public uncertainty on the safe use of these passive restraint components. A main goal of the air bag module development must be to balance the out-of-position risks with the overall occupant protection performance to reach the highest biomechanical quality. Further considerations must be given to the development and production costs, quality and styling of the air bag module and steering wheel. Design, function, cost and styling have competing impact during the product development phase. Economic and efficiency factors require new production and manufacturing of systems that use pre-assembled components as assembly groups, such as the so called “high level assemblies.”

Current restraint systems with pretensioner, belt force limiter and airbag are not only designed for a crash test such as FMVSS 208. Automobile manufacturers carry out test configurations over and above these parameters to check the effectiveness of restraint systems, for instansce: NCAP, frontal crash with 40% offset against a deformable barrier, which is a provision of the ECE-R 94 and a binding prescription for all new European vehicles as of October 1998. However it is not possible to cover the entire spectrum of accident configurations found in real-world accident occurrences. In the development of restraint systems with reference to aspects of occupant biomechanics, the possibilities on the testing side for reproducing reality are particularly limited. Aside from the 50%-HYBRID III dummy as occupant of average size and weight, only the two extremes of the occupant - 5% female dummy and 95% male dummy - are used.

After analyzing existing vehicle motion data for low speed rear-end impacts, this paper develops an efficient mathematical model to simulate such testing. The proposed idealization is believed to be as simple a model as is possible for delivering reasonable time history responses of the two vehicles involved, i.e. a linear two-degree of freedom mass/spring/dashpot system. A closed-form solution of the equations is then developed and numerical results based upon it are compared to the time histories of the actual vehicle motions and peak loads. Experimental data is used to determine the effective stiffness and damping for the two degree of freedom model. Comparisons of results obtained from the analysis with scaled test data agree favorably, thus identifying the basic design parameters which could be used to minimize vehicle damage and passenger loading.

Bridge the interface barriers between customer & manufacturer and between manufacturer & supplier. Value Analysis/Value Engineering (VA/VE) provides a common measure and a method to tie customer value to product design, manufacturer processes and supplier processes. This approach fine tunes the entire value-adding chain to deliver superior customer value and minimize costs. This paper shows how to: Use Customer Value Analysis to develop a value based competitive strategy. Use VA/VE to align products, services and processes to fulfill that strategy. Use joint manufacturer & supplier VA/VE to integrate supplier processing with product design and competitive strategy. The paper concludes with a case example.

The increased focus on occupant protection by automobile manufacturers combined with incessant consumer demand for safety features such as dual airbags has posed design engineers with major challenges in the field of Instrument Panel (IP) design. Typically, airbags are designed to deploy when the speed of the automobile is above 13 mph in a frontal impact. The airbag door should meet head impact requirements for unbelted occupants involved in low speed impacts (<15mph) when airbags are not deployed. This paper describes how computer aided engineering (CAE) simulation techniques were used in improving the design of the passenger airbag door of a full size van for head impact performance. Fewer tests were conducted primarily for validation, which resulted in significantly less prototypes, costs and time.

This paper demonstrates how to use advanced finite element modeling techniques such as airbag modeling, material plasticity with consideration of failure and effects of temperature and strain rates, surface to surface sliding contact treatment, nonlinear transient dynamics, and so on, to perform structural analysis of airbag modules. A technique to calculate the transient dynamic loads on the structure of an airbag module is first demonstrated. The dynamic transient loads on the structure are calculated by an integrated airbag modeling and sliding contact treatment with the structural model of the airbag module. Other techniques for modeling special design features of the airbag module, such as tear seam, tear tie, and hinge on a cover, press fit of a gas defuser, housing, connections of each component, and so on are also illustrated and discussed. All modeling techniques are illustrated by analysis examples in product development.

The questions of how to price a product-line across segments and to price an element of the line within a segment is explored here using the market for family automobiles as a test case. Monroe's (1990) psychometric model is considered for pricing between segments and the demand model of Cook and Kolli (1994) and Donndelinger and Cook (1995) is used to study pricing within segments. The segmentation of the market for family automobiles is rationalized by sorting vehicles into groups having similar prices and overall values. A rule of thumb is introduced for pricing in a dynamic market in which the values, costs, and prices of the competing products are volatile as a result of intense competition generating product improvements on a continuing basis.

Capturing the cost and schedule savings available by the best use of first tier suppliers is a key goal of any assembler (prime contractor) of manufactured products. Ensuring database commonality is a key enabling practice in reaching this goal. In this paper, a simple supplier cost model is presented, and its implications as to supplier strategy are discussed. A number of different supplier strategies are reported on, based on case studies. The types and amounts of information which will be easily available to the assembler are qualified. The impact of supplier strategy on database commonality is described.

There has always been great interest in reducing cost while enhancing value and thereby increasing productivity. Although some feel innovation, quality, and firm value may suffer when productivity gains and cost reduction are emphasized, many feel value-based decision-making techniques may help the process. In this study, the discretionary investment decisions made by the management teams using value-based decision making are examined. The results show that pursuit of cost-reduction strategies and incremental improvement strategies did not inhibit the pursuit of function-increase and innovative strategies. The results also showed that varying the performance criterion used as the principal measure of goal achievement appeared to alter management decisions. The effect seemed to be more evident in the priority assigned to innovative alternatives and in the timing of their implementation than in the investment in incremental improvement.

The Value Engineering (VE) process. and therefore. the equation “Value = Function/Cost” is being used in the auto industry quite extensively. However. there are significant differences in the use of “tost” between the automobile industry and the more traditional users of the V.E. process: e.g.. defense. and construction. The tendency in the automobile industry has been to use a per unit variable cost. This approach, while giving adequate results for comparative purposes, is not technically correct. since the cost should include the total life cycle cost. Under some circumstances. this simplified approach could give erroneous results, for example, when incremental investment is a significant consideration in the decision-making process. This paper will suggest a method for establishing a total life cycle cost for use in the Value Engineering equation in Value Engineering an automotive component system.

Engineers, marketing specialists, and planners responsible for making the numerous cost/benefit trade-offs that arise in the development of a new product need to understand how the attributes of the product generate value to the customer. A recently proposed methodology for benchmarking product value is tested here using five family automobiles competing in the middle product segment. Reasonable agreement is found between value differences estimated from an analysis of demands and prices and those estimated from attribute differences. This finding supports the use of the methodology in forecasting the demands and profits of future products based upon the improvements expected in their attributes.

Product engineers and product planners are routinely faced with trade-off decisions involving the cost of adding a product feature or modifying an existing feature versus its added value to the customer. The purpose of this paper is to assess the use of a personal computer (PC) for surveying respondents' willingness to pay (WTP) for four options - two-tone color, 4x4 drive, sporty trim package, and extended cab -- available on the base 1997 Ford F-150 truck. The results show that the respondents' stated WTP reflected the value of the options as determined from their prices and fraction of sales.

In developing new products and improving existing products, engineers make numerous trade-offs between the cost of a new or modified feature and its value to the customer. One method for estimating value is to ask potential customers their willingness to pay (WTP) for the product change. Their stated WTP may, however, depend upon how the question is framed. Mail survey techniques based upon simulated choice experiments were used for estimating value to the customer. The main objective was to explore how the framing of the survey questions affected the WTP response and if one or more of the methods provided simulated responses in reasonable agreement with actual buyer behavior. It was found that the best way to frame the questions was to give respondents multiple choices for price of the alternative versus the baseline product as opposed to having a choice of only one price or having to write in a price representing their WTP.

This paper summarizes an investigation of the changes in combustion and particulate emissions caused by thermal barrier coatings placed in the combustion chamber of a diesel engine. The engine was a Yanmar TS 180 single cylinder diesel utility engine with a continuous rating of 15 HP (11.2 kw) @2400 RPM. The test protocol was the International Standards Organization (ISO) 8178 Standard Type-E3 test which simulates a marine diesel engine. Total particular matter emissions were measured by collection on Pallflex, filters via fractional sampling using a Sierra Instruments BG-1 Micro-Dilution Test Stand. The engine was operated with and without the thermal barrier coatings. The coated parts are the piston crown, the cylinder head (fire deck), and the valves. Scanning electron micrography (SEM) provided analysis of particulate size, microscopic structure and elemental composition of the particulate samples.

Dealership's management must be innovators in today's competition. They must increase customer satisfaction by creating Value-Added service and product and also increase total dealership profit. The basic premise of using “Value-Added” is also called Common Sense Management (CSM). CSM can be then defined as: A business is a system of resources used for creating value. Management's function in the business is to find ways to increase system productivity, where system Productivity = Value Created divided by Resources Expended ( ). This is a relatively easy formula to learn, but not many businesses today live by it. Value-added management (VAM) is then the system that seeks to increase value while simultaneously eliminating waste. VAM can include a variety of quality tools and processes, such as total quality management (TQM), value-based decision making, and reengineering.

An old and a new diesel engine and three diesel engine fuels were compared regarding the concentration of particles in diluted exhaust immediately after dilution and after 40 seconds of aging. The flow of dilution air was adjusted to give a particle concentration of about 2 mg/m3. Filters were weighed and analysed with a Scanning Electron Microscope. The mean volume of soot particles were in the range 0.01-0.05 ·m 3, the mean weight, 10-40 femtogram. The mean density of the particles was found to be 1.7. In the different experiments the densities of the particles varied considerably indicating complicated agglomeration and adsorption-desorption processes. The new engine emitted significantly lower concentrations of particles than the old engine when measured in the dilution tunnel. The new engine was not better than the old and worn engine when results obtained after aging of the particles in the chamber were compared.

This paper reviews the trend in worldwide exhaust emission regulations for heavy-duty diesel engines and common key technologies that must be developed and applied in order to meet these regulations. The common key technologies are intake and exhaust system with turbocharger and intercooler, electronically controlled high-pressure fuel injection system, exhaust gas recirculation, and exhaust gas after-treatment devices. This paper also introduces test results of common key technologies, concepts for low-emission heavy-duty diesel engines, and the possibilities for meeting future exhaust emission legislation is described.

Some catalysts such as copper zeolites have shown promise for direct NO decomposition and selective NO reduction via hydrocarbons in lean exhausts. This paper describes modeling calculations for the performance of a Cu-ZSM-5 NOx reduction catalyst. The numerical model simulates the multi-component transport and reaction processes that occur within a catalyzed monolith support. The surface boundary conditions for the reacting species are satisfied through use of multi-dimensional Newton-Raphsson iteration. The model is used to formulate global rate expressions for the oxidation of C3H6 and the reduction of NO by adjusting kinetic parameters until predicted conversion efficiencies match experimental data. Then the numerical model is compared to data from higher space velocities to test the validity of the kinetic model. The comparison at higher space velocity shows reasonable agreement, although additional optimization of the kinetic parameters is possible.

Experimental catalysts for the reduction of oxides of nitrogen (NOx) were evaluated on a 258-horsepower (192 kW) direct-injection heavy-duty diesel engine. An experimental reductant delivery system provided supplementary hydrocarbons for the reduction of NOx. Initially, diesel fuel was used as the supplementary reductant. Early experiments resulted in a 10 to 17 percent reduction in NOx emissions when tested using the heavy-duty engine transient Federal Test Procedure (FTP), and a 30 to 40 percent reduction at selected steady-state catalyst inlet temperatures. A fuel economy penalty of five percent was measured for initial FTP experiments. Emissions of total hydrocarbons (HC), carbon monoxide (CO), and particulate matter (PM) tended to increase during initial experiments with the addition of the supplemental reductant, but these emissions decreased with the incorporation of improved catalyst formulations and reductant fuel spray calibrations.

Measurement procedures for the legal limitation of emissions from heavy duty engines should adequately reflect the actual use of such engines in practice. Equally important is the possibility to monitor the emision performance of certified engines on the market. This paper gives a short overview of the experiences with the Dutch in-use compliance program for HD vehicles. The results indicate that such a monitoring of the existing fleet is of great importance for the national authorities. This means that any measurement procedure envisaged for legislation purposes should take account of the requirement of relatively easy monitoring of the emission behaviour in service just as much as the requirement of adequate simulation of practical vehicle operation.