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To understand how the passenger compartment cavity interacts with the surrounding panels (roof, windshield, dash panel, etc) a numerical panel contribution analysis was performed using FEA and BEA techniques. An experimental panel contribution analysis was conducted by Reiter Automotive Systems. Test results showed good correlation with the simulation results. After gaining some insight into panel contributions for power train noise, an attempt was made to introduce beads in panels to reduce vibration levels. A fully trimmed body structural-acoustic FEA model was used in this analysis. A network of massless beam elements was created in the model. This full structural-acoustic FEA model was then used to determine the optimal location for the beads, using the added beams as optimization variables.

Environmental costs are a delayed financial burden that result from product decisions made early in the product life cycle--early material choices may create regulatory and waste management costs that were not factored into the acquisition cost. This paper outlines a step-wise approach to determine decision points; environmental, health, safety and recycling (EHS&R) cost drivers that affect decisions; and sources of information required to conduct a Life Cycle Management (LCM) review. Additionally, how LCM fits into the larger concurrent engineering framework is illustrated with an electrocoat primer example. Upstream and downstream supply chain processes are reviewed, as well as organizational challenges that affect the decision process.

In recent years, strict weight reduction targets have pushed auto manufacturers to use lighter gauge sheet steels in all areas of the vehicle including exterior body panels. As sheet metal thicknesses are reduced, dentability of body panels becomes of increasing concern. Thus, the goal becomes one of reducing sheet metal thickness while maintaining acceptable dent resistance. Most prior work in this area has focused on quasi-static loading conditions. In this study, both quasi-static and dynamic dent tests are evaluated. Fully assembled doors made from mild, medium strength bake hardenable and non-bake hardenable steels are examined. The quasi-static dent test is run at a test speed of 0.1 m/minute while the dynamic dent test is run at a test speed of 26.8 m/minute. Dynamic dent testing is of interest because it more closely approximates real life denting conditions such as in-plant handling and transit damage, and parking lot damage from car door and shopping cart impact.

Fastener failure due to hydrogen embrittlement is of significant concern in the automotive industry. These types of failures occur unexpectedly. They may be very costly to the automotive company and fastener supplier, not only monetarily, but also in terms of customer satisfaction and safety. This paper is an overview of a program which one automotive company initiated to minimize hydrogen embrittlement in fasteners. The objectives of the program were two-fold. One was to obtain a better understanding of the hydrogen embrittlement phenomena as it relates to automotive fastener materials and processes. The second and most important objective, was to eliminate hydrogen embrittlement failures in vehicles. Early program efforts concentrated on a review of fastener applications and corrosion protection systems to optimize coated fasteners for hydrogen embrittlement resistance.

Environmental issues continue to emerge as a significant concern of the public today. End-of-pipe controls have proven to be costly solutions and have not addressed the root causes of environmental issues. Pollution prevention programs better address concerns and produce more cost-effective solutions. Additionally, regulations can no longer be addressed in isolation. Industry must view regulatory requirements as other business matters are addressed. The integration of regulatory requirements into the business plan focuses the cost of compliance on appropriate products or processes and exposes formerly hidden costs. For highly outsourced OEM's, supplier participation is critical to the success of any program. The bounds of Early Supplier Involvement (ESI) are extended through an integrated global raw material strategy that encompasses regulated substance control, material selection and rationalization, and design for recyclability/separability.

The bounds of Early Supplier Involvement (ESI) are extended through an integrated global raw material strategy which encompasses regulated substance control, material selection and rationalization, and design for recyclability/separability. A life cycle management (LCM) model is used to evaluate environmental, health, safety and recycling (EHS&R) issues in a systematic business decision framework.

Voltage and current surges are a major concern when it comes to ensuring the functional integrity of electrical and electronic components and modules in an automobile system. This paper presents a computer simulation study for analyzing the effect of high voltage spikes and current load dump on a new Integrated Driver/Receiver (IDR) IC, currently being developed for a J1850 Data Communication Bus in an automobile. It describes the modeling and simulation of the protection structure proposed for the device. The simulation study yields a prediction of current and voltage capability of the protection circuit based on thermal breakdown and transient responses of the circuit. Two levels of modeling, namely, the behavioral level model and the component level model, are used to generate the simulation results. Experimental data will be acquired and used to validate the simulation model when the actual device becomes available.

Basic procedures are described for the design and development of flexible drive plates that couple automatic transmissions to engines. An innovative combination of analysis and test techniques were employed during the development of a drive plate for a turbocharged diesel truck engine when premature failures occurred. FEA (finite element analysis) was expanded from use as a preliminary design tool to the prediction of high stress conditions and the loading that caused them. A laboratory test was developed to rapidly assess drive plate design changes based on these FEA predictions.

The impact response of foam is investigated using Finite Element Analysis (FEA). A procedure will be described for determining the material constants used in the FEA material models. The procedure uses compressive uniaxial, force versus displacement, and triaxial, pressure versus volume-change, data. After the material model is constructed using the uniaxial and triaxial data, FEA is used to predict the results of a free-moving-mass striking rigidly backed foam. The limitations of the current material models are also addressed.

Seats play an important role in determining customer satisfaction and safety. They also represent three to five percent of the overall vehicle cost and weight. Therefore, automotive manufacturers are continuously seeking ways to improve the areas of comfort, safety, reliability, cost and weight within the seat system. The purpose of this paper is to review the development of an automotive front seat constructed of injection molded nylon frames and metal mechanisms. This development program was initiated for the purpose of reducing vehicle weight while increasing the reliability and safety of the front seats. This paper will review the material and process selection decision, a design overview, the performance criteria and the results of tests performed on the injection molded front seats.

This paper presents a method of accounting for sample variability and sample size in establishing the acceptable bogey levels. The technique makes use of the statistical tolerance theory which accounts for the variability of the sample mean and standard deviation by determining a K-factor adjusted for sample size. The result is a tolerance that is reasonably assumed to cover a specified fraction of the population of parts. The technique, although not as simple as a fixed bogey, does discriminate between designs with different levels of energy management robustness.

New methods are required for implementing the proliferation and sophistication of electronic controls and features to meet the customer's quality expectations. Vehicle electronic integration provides a potential solution for reconciling the seemingly contradictory objectives of high quality at reasonable cost. No module can be considered independently with this global approach. OEM subsystem and component suppliers' devices will need to play in concert with the overall vehicle's electrical/electronic strategy. Some new, separately packaged electronic features may eventually be assimilated within the framework of other electronic controllers.

A highly competitive market and increased emphasis on quality have gear designers searching for additional tools to produce accurate gearsets in a condensed timeframe. To meet this challenge, a Graphics Engineering method has been developed to enhance traditional gear design techniques. Graphics Engineering links interactive graphics, finite element analysis and solid modeling into a graphics/analysis development package. Starting with gear and cutter data derived by conventional techniques, it provides cutter paths and involute profiles for geometry, strength, and physical property analysis. The comprehensive data obtained through Graphics Engineering provides a powerful tool for the gear designer to increase gearset accuracy and reduce design iterations.

There is a major problem in maintaining the records of the more than 275 million vehicles presently registered throughout the world. Monitoring the life of a given vehicle from its fabrication to its destruction can best be accomplished by the inner facing of major computer programs and a uniform system for vehicle identification. The Vehicle Identification Number (VIN) is the legal identification of the vehicle. Every manufacturer has the responsibility of assigning a unique VIN to each vehicle, in compliance with numerous procedures, standards and laws. The VIN is attached to the vehicle, stamped and embossed on components, and printed on tamper resistant labels. It is printed on hundreds of documents and maintained in numerous files.

Starting in 1965 and continuing through 1972, the Radio Committee of the Motor Vehicles Manufacturers Association (MVMA) has been the coordinator of a number of electromagnetic research projects. These investigations have included extensive applications of the updated SAE Standard, Measurement of Electromagnetic Radiation From Motor Vehicles (20-1000 MHz)-SAE J551a. Furthermore, there were joint testing programs with the Electronic Industries Association which encompassed measuring degradation in the performance of Land Mobile Radio Service receivers resulting from varying levels of impulsive-type radiation from motor vehicles. In addition, efforts were expended in using statistical approaches for testing a number of hypotheses covering a conversion of impulsive vehicle noise data to the interference potential to Land Mobile receivers.

A procedure has been developed for measuring the relative visibility of automotive instrument panel graphics and components. Through use of a Luckiesh-Moss Visibility Meter, discreet values of visibility can be assigned to visual targets and related to driver reaction time. Also, eyes off the road lapsed time boundaries may be established which will define visibility requirements necessary to serve the total driver population. These requirements can be translated into meaningful guidelines or standards for visibility attributes such as size, shape, color, contrast, and position of graphics, controls, and indicators. How visibility measurements are made and interpreted and the visibility measuring facility are discussed in this paper.

The paper outlines testing, development, and operation of the first production four-wheel slip control system for passenger cars in the United States. The Chrysler Corp. calls the system “Sure-Brake,” but it is more generally known as “anti-skid.” The first portion of the paper deals with considerations that led Chrysler into the Sure-Brake system, the philosophy behind the system, and a detailed explanation of its operation. The second portion deals with the development and testing of the system, leading to its release as an option on the 1971 Imperial. The testing program introduced a new dimension to brake engineering. Before the advent of wheel slip control systems, many thousands of brake tests were conducted but were always terminated at the point of skid. These tests were also conducted mainly on black top or concrete roads. For the first time, thousands of stops were made at maximum deceleration on every available surface.

This paper describes techniques that predict and analyze dynamic response of vehicles traversing random rough surfaces. Road irregularities are statistically classified by frequency and amplitude distribution. This classification determines the nature of random inputs to mathematical vehicle models and allows computer prediction of dynamic response of a simulated vehicle. Once inputs and models are defined, parametric analysis with output criteria specified statistically can be performed. This allows prediction of vehicle riding quality and evaluation of design concepts. Statistical analysis of accelerometer measurements on actual vehicles permits verification of the design process and meaningful comparison between vehicles.

Present techniques for classification and analysis of surface roughness are based on a trace of surface profile, or a measure of arithmetic mean, or rms value of the profile height, but this information is not adequate, and a new technique has been developed to classify surface roughness based on frequency content of the variance of the surface profile. A digital computer frequency filter has been devised to allow differentiation between roughness height and waviness or general surface contour. Three representative surfaces have been measured and classified according to this analysis and data are presented in support for roughness classification techniques.

IN 1951 Chrysler Corp. began working on a new torsion suspension. In this paper the authors describe details of the development and design of the suspension, now available on 1957 cars. The authors claim the Torsion-Aire suspension has the following advantages: reduced highspeed float, boulevard harshness, impact harshness, road noise, body roll, nose dive, and acceleration squat; better directional stability and cornering ability; fewer lubrication points; and a better balanced ride. The main feature of the front suspension is the use of torsion bars. One of the principal advantages of torsion bars is their weight: 10 lb as compared to 15.8 lb for a 1956 production coil spring.