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“There's nothing new under the sun,” the old proverb says. But you only have to read a magazine, scan a periodical, listen to the radio, watch television, or glance at the multitude of ads that promise that such and such product is the latest trend or has up-to-date, state-of-the-art technology, to seemingly prove the old proverb wrong. However, old proverbs become old because they withstand the test of time. In this case, a hasty judgement should be withheld. Currently, as in the past, the above holds true for car radios as well. Whether in the United States, Europe, Canada or Latin America, the public has always been susceptible to last minute technological advances. It is curious then, that as far as car radio styling is concerned, their appearance has been typically rather conservative, and that it is only recently that styling has begun to change to be more in tune with the times.

A cycle counting algorithm that will reduce a complex history into a series of discrete cycles is presented. The cycles determined by this technique are defined as closed stress-strain hysteresis loops of the type obtained from constant amplitude tests. Using the computer cycle counting algorithm, life predictions were made and compared with experimental results. These predictions were found to be typically within a ±3 factor of error. Also, the computer counting method was found to yield more accurate life predictions when compared to the histogram and range counting methods.

Automakers have the opportunity to utilize bio-based composite materials to lightweight cars while replacing conventional, nonrenewable resource materials. In this study, Life Cycle Assessment (LCA) is used to understand the potential benefits and tradeoffs associated with the implementation of bio-based composite materials in automotive component production. This cradle-to-grave approach quantifies the fiber and resin production as well as material processing, use, and end of life for both a conventional glass-reinforced polypropylene component as well as a cellulose-reinforced polypropylene component. The comparison is calculated for an exterior component on a high performance vehicle. The life cycle primary energy consumption and global warming potential (GWP) are evaluated. Reduced GWP associated with the alternative component are due to the use of biomass as process energy and carbon sequestration, in addition to the alternative material component's lightweighting effect.

This paper provides an overview of the dual EGO sensor method for OBD-II catalyst efficiency monitoring. The processes governing the relationship between catalyst oxygen storage, HC conversion efficiency, and rear EGO sensor response are reviewed in detail. A simple physical model relating catalyst oxygen storage capacity and rear EGO sensor response is constructed and used in conjunction with experimental data to provide additional insight into the operation of the catalyst monitor. The effect that the catalyst washcoat formulation has in determining the relationship between catalyst oxygen storage capacity and HC conversion efficiency and its impact on the catalyst monitor is also investigated. Lastly, the effects of catalyst failure mode, fuel sulfur, and the fuel additive MMT on the catalyst monitor's ability to properly diagnose catalyst function are discussed.

This paper begins with a comparison of the automotive power supply and loads in the early 1950's (near the end of the six-volt era) to the modern counterpart in the early 1990's (possibly near the end of the 12-volt era). A typical power supply specification sheet is developed based on the in-vehicle performance characteristics. From this summary, two attributes are noted: first, the system voltage is not very stable and second, transient protection is limited. With this awareness and the knowledge that the power supply of the future will need architectural change, a review of the design assumptions using a total system view and a long term outlook is advanced. Using a rule based design process and employing available technology to enhance the power system architecture, a number of elements are proposed for consideration in new designs.

The present work discusses an objective test and analysis method developed to quickly quantify steering gear rattle noise heard in a vehicle. Utilizing envelope analysis on the time history data of the rattle signal, the resulting method is simple, fast, practical and yields a single-valued metric which correlates well to subjective measures of rattle noise. In contrast to many other rattle analysis methods, the approach discussed here is completed in the time domain. As applied to rattle noise produced by automotive electric steering systems, the metric produced with this analysis method correlates well with subjective appraisals of vehicle-level rattle noise performance. Lastly, this method can also be extended to rattle measurements at the component and subcomponent level.

Variable amplitude torsion, bending, and combined torsion and bending fatigue tests were performed on an axle shaft. The moment inputs used were taken from the respective history channels of a cable log skidder vehicle axle. Testing results indicated that combined variable amplitude loading lives were shorter than the lives of specimens subjected to bending or torsion alone. Calculations using strain rosette readings indicated that principle strains were most active around specific angles but also occurred with lesser magnitudes through a wider angular range. Over the course of a biaxial test, cyclic creep narrowly limited the angles and magnitudes of the principal strains. This limitation was not observed in the calculated principal stress behavior. Simple life predictions made on the measured strain gage histories were non-conservative in most cases.

Side impact collisions account for about 29% of all vehicle occupant fatalities and for about one-fifth of all the “harm” to vehicle occupants. This paper addresses many aspects of side impact induced injuries which vehicle planners and designers may choose to consider during the evolution of a vehicle design. The proposed NHTSA side impact test, side impact dummies, the biomechanics of different human body areas and general concepts for increased occupant protection are discussed from a theoretical point of view. It is believed that this paper or a future update of it, can only become a useful tool when there is general agreement that it reflects solid biomechanical direction which in turn, can be reflected in actual, practicable, responsible hardware design.

Emerging markets and South America in particular, have quickly become the cornerstone of major automotive companies in recent years. Currently, all major players are located in the region, and this has created an excellent environment for developing market-tailored products. The trend in the design and technology community is one which allows the final customer to improve his own safety and reduce overall power consumption. Throughout the entire automotive industry, the lighting system has always had a very important role to play during its long history. In the past 50 years, vehicular lighting has achieved an important status due to its close relationship by enhancing passenger and vehicle security. In addition, there is still room for improvement in the halogen front lighting system. Particularly, it is of utmost importance to highlight the implementation of NEO (new efficient optics).

It is frequently desirable to construct a characterization of vehicle deceleration which is significantly simplified from its actual time history. A number of interesting techniques have been developed to perform this characterization based upon polynomial and Fourier-type series approximations and utilizing goodness of fit criteria related to both least squared error and the satisfaction of boundary conditions. Extensive mathematical occupant simulations indicate that characterizations involving as few as four parameters are adequate to describe the primary effects of complex vehicle deceleration time histories as they influence occupant dynamics with conventional restraint systems.

The objectives of this study were a) to determine how expert judges categorized valid Integrated Vehicle-Based Safety Systems (IVBSS) Forward Collision Warning (FCW) events from review of naturalistic driving data; and b) to determine how consistent these categorizations were across the judges working in pairs. FCW event data were gathered from 108 drivers who drove instrumented vehicles for 6 weeks each. The data included video of the driver and road scene ahead, beside, and behind the vehicle; audio of the FCW alert onset; and engineering data such as speed and braking applications. Six automotive safety experts examined 197 ‘valid’ (i.e., conditions met design intent) FCW events and categorized each according to a taxonomy of primary contributing factors. Results indicated that of these valid FCW events, between 55% and 73% could be considered ‘nuisance alerts’ by the driver.

The Composite Lightweight Automotive Suspension System is a composite rear suspension knuckle/tieblade consisting of UD prepreg (epoxy resin), SMC (vinylester resin) carbon fibre and a steel insert to reduce the weight of the component by 35% and reduce Co2. The compression moulding manufacturing process and CAE optimisation are unique and ground-breaking for this product and are designed to allow high volume manufacture of approx. 30,000 vehicles per year. The manufacturing techniques employed allow for multi-material construction within a five minute cycle time to make the process viable for volume manufacture. The complexities of the design lie in the areas of manufacturing, CAE prediction and highly specialised design methods. It is a well-known fact that the performance of a composite part is primarily determined by the way it is manufactured.

The work force in design and drafting is undergoing the most dramatic change in its history with the advent of Computer Graphics. The computer and CRT are replacing the traditional T, square, pencil, and compass. Work is being accomplished by one person where manually it would have required several. Even the end product is changing from layouts and details to digital data and mathematical surfaces. Retraining the highly skilled and experienced work force is the key to taking full advantage of this rapidly expanding technology.

Over the past several years a task group within the SAE Automotive Corrosion and Protection (ACAP) Committee has conducted extensive on-vehicle field testing and numerous accelerated lab tests with the goal of establishing a standard accelerated test method for cosmetic corrosion evaluations of finished aluminum auto body panels. This project has been a cooperative effort with OEM, supplier, and consultant participation and was also supported in part by DOE through USAMP (AMD 309). The focus of this project has been the identification of a standardized accelerated cosmetic corrosion test that exhibits the same appearance, severity, and type of corrosion products that are exhibited on identical painted aluminum panels exposed to service relevant environments. Multi-year service relevant exposures were conducted by mounting panels on-vehicles in multiple locations in the US and Canada.

The development of vehicular gas turbine engines to operate at temperatures up to 2500°F has been in progress for some time. The purpose of this paper is to review the rationale behind this engine, to highlight the major hot flowpath components being developed, and to provide information on the progress of this program.

TWENTY-FIVE-YEAR statistics, detailed in this paper, show declining accident and fatality rates despite radical increase in vehicle registrations and annual vehicle miles. The author shows how the passenger-car industry has built safety into vehicles to the point where-as an example-only 14% of accidents on the Pennsylvania Turnpike over its 13-year history were attributed to vehicle failures. Paralleling these efforts and the increasing emphasis on safer highways, better traffic management and driver education, are extensive studies aimed at bypassing the human factor and increasing human safety in automotive vehicles. Among those described here are crash investigations, laboratory tests of safety devices, and establishment through various other means of design criteria for human impact tolerance.

A new P/M part is created due to one of three reasons: 1) Cost savings over a manufacturing method for a current part, 2) Cost savings over an alternative method to manufacture a new part or, 3) it's the only practical way to manufacture the part. In today's quality conscious atmosphere at Ford the suppliers of P/M parts should be aware of their responsibilities in producing a P/M part to required standards. The producer must become involved in early feasibility issues, prove process capability and maintain capability on an ongoing basis. A case history of such an evaluation will be discussed from initiation through a second generation design.

A new, low cost method to determine the accumulated structural loads in service (not to predict component fatigue life) that requires practically no on-board instrumentation is discussed. This method makes use of S/N fatigue life gages with high-gain mechanical multipliers bonded to a component. Permanent change in gage resistance results from the number of component load cycles and their magnitudes. These resistance change data are then used to reconstruct the load range history. The computer program on this method is listed in the Appendix. Results of laboratory tests conducted to validate the new method and evaluate the behavior of the multipliers over a practical range of operating temperature and strain magnitude and frequency are presented. The component load range distribution estimated by this method is compared to that measured by conventional methods for a vehicle operating on a proving ground route.

In this paper a diagnostic design process is proposed for developmental vehicles where mainstream design process is not well-suited. First a review of current practice in on-board vehicle fault diagnostics design is presented with particular focus on the application of this process to the development of the Ford Escape Hybrid Electric Vehicle (HEV) program and a demonstration Fuel Cell Electric Vehicle (FCEV) program. Based on the review and evaluation of these experiences, a new tool for diagnostics design is proposed that promises to make the design more traceable, to reduce the repetition of work, and to improve understandability and reuse.

An overview of the current status and emerging trends in durability-related technologies is presented as an introduction to a series of papers covering applications of durability analysis in design. Problems of information management associated with technology integration are discussed along with the probable impact of new design tools on product development and validation.