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This paper presents the possibility of utilizing shock absorbers to decrease the aggresivity of a large car towards a small car at an impact of 40 mph. Reduction of such aggresivity would result in more damage to the large car, thereby reducing the impact on the small car. The conclusions demonstrate a definite decreased aggresivity of the larger car. Increase of the shock stroke does cause the large car to be crushed more in car-to-car collision. However, this occured at speeds below 25 mph, not the 40 mph as set by the study.

The purpose of this paper is to illustrate the use of Taguchi experimental methods as a development tool for designing a manufacturing process for inner door panels. Through analysis of experimental results, it was possible to identify critical manufacturing variables, as well as demonstrate inherent process capability.

A new tool for analyzing transmissions that use planetary gearsets is presented. With this tool, entire transmissions are usually represented by a single lever, and the calculation of most characteristics is as simple as summing moments of a lever. A miniature cookbook of levers, for various planetary arrangements is included which can be helpful in selecting a planetary to achieve the desired objectives of a user.

THIS paper describes the springs, control system, and ride of the air suspension system on the 1958 Buick. The system is a semiclosed one, providing a variable-rate suspension, automatic leveling and trim control, and manual lift. The latter feature is a knob below the instrument panel which can be operated when necessary to cope with unusual clearance conditions. The car remains at the same height with loads of up to five passengers and 500 lb in the trunk. The authors describe the road-holding ability of a car with this suspension system as excellent.

The object of this paper is to present an overview of the procedure leading to the selection of suspension system pivot points, show how to resolve terrain and maneuver loads at the tire contact patch to the vehicles' structure, illustrate the modeling technique used for stress analysis of suspension system components, and illustrate a few examples of suspension system models used to aid in the solution of ride and handling problems.

This paper describes some methods for greatly reducing or possibly eliminating subjective tuning of suspension parts for ride and handling. Laptop computers can now be used in the vehicle to guide the tuning process. The same tools can be used to select solutions that reduce sensitivity to production and environmental variations. OBJECTIVE Reduce or eliminate time required for tuning of suspension parts for ride characteristics. Improve the robustness of ride performance relative to variations in ambient temperature and production tolerances. PROBLEM REQUIRING SOLUTION AND METHOD OF APPROACH Traditional development programs for new vehicles include time-consuming subjective ride evaluations. One example is shock absorber tuning. Even if sophisticated models define force-velocity curves, numerous hardware iterations are needed to find valvings that will reproduce the curves. Many evaluation rides are needed to modify the valvings to meet performance targets.

A good manager knows how to administer, direct, and allocate the resources of his organization to the best advantage. The main resources available to him are money; facilities, equipment, and material; people; time; information; and company reputation or image. These resources all interact to create conflicting demands. It is the job of the management scientist to resolve these conflicts satisfactorily through the application of quantitative techniques, some of which are described.

Typically, “Reliability and Maintainability (R&M)” is perceived as a tool for products alone. Putting emphasis on reliability only at the cost of maintainability is another archetype. Inclusion of both reliability and maintainability (R&M) in all the phases of the machinery and equipment (M&E) life cycle is required in order to be world competitive in manufacturing. R&M is mainly a design function and it should be a part of any design review. Inclusion of the R&M concept early in the life cycle of M&E is key to cost effective and competitive manufacturing. Neither responsive manufacturing nor preventive maintenance can raise it above the level of inherent R&M.

Resin transfer molding (RTM) is the process of choice for the Body Panels of the Viper Sports car. The objective of this paper is to outline the reasons for the choice of RTM, and discuss development of technology for Class A surfaces and the paint system. Accomplishments to date and finally the work yet to be completed will also be defined. Conclusions from the work to date indicate that the RTM process enables a reduction in vehicle development time through faster prototypes and tool build times and that high quality, Class A surfaces can be successfully achieved even with epoxy tools. Additional work is ongoing to reduce cycle times and finishing costs, and to improve the in-process dimensional stability.

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.

Higher horsepower per liter engines have put more demand on the crankshaft, often requiring the use of forged steel. This paper examines cost reduction opportunities to offset the penalties associated with forged steel, with raw material and machinability being the primary factors evaluated. A cost model for crankshaft processing is utilized in this paper as a design tool to select the lowest cost material grade. This model is supported by fatigue and machinability data for various steel grades. Materials considered are medium carbon, low alloy, and microalloy steels; the effects of sulfur as a machining enhancer is also studied.

The Paint Technology Globalization effort is recognized as an important step of accomplishing the leveraging of worldwide resources of both engineering and purchasing in order to improve General Motor's competitiveness. The process used, the benefits derived, the current status of the effort, and the expected results (deliverables) are discussed. These include common materials, processing, and equipment paint specifications to be included in purchasing bid packages.

A front suspension laboratory test procedure was developed to reproduce time-correlated fatigue damaging events from a light truck road durability test. Subsequently, the performance of front suspension systems for the GMT 400 light truck program were evaluated in terms of customer reliability. Both prototype and pilot testing, as well as computer modeling, were used in the evaluation.

Saturn currently injection molds and paints PPE+PA66 exterior body panels in its Spring Hill, TN facility. These manufacturing operations result in a continuous stream of waste material that needs to be responsibly and economically managed. This paper will summarize the process that General Motors and Saturn used to evaluate and validate the use of post-industrial painted PPE+PA66 reprocessed material in Saturn and General Motors' wheel trim applications (wheel covers). Not only did this project increase the amount of recycled content in General Motors' vehicles, but it also provided Saturn Corporation with a favored outlet for an internal waste stream.

Proper performance of a vehicle's suspension system is required to ensure safe, comfortable operation of a vehicle. A suspension-testing device that can determine the condition of the suspension system, specifically the dampers, has been designed. The tests described by this paper seek to evaluate the performance of the device by testing vehicles and comparing to other methods of measuring suspension system performance that are currently in use. The suspension-testing device has the ability to discover degraded performance of the suspension system through a 2-minute test with the vehicle in operating condition.

Electro-Motive Division of GM jointly with HRL Laboratories have developed a software tool, called TechPro, which assists in troubleshooting of diesel locomotives. The tool has been tested extensively in the field for the last two years. It has improved significantly the quality of diagnosis of locomotives. The tool is based on Graphical Probabilistic Models and Case Data Bases. We will discuss the design of the tool, its performance and will show its relevance to diagnosis of automobiles.

Truck driver shin-knee and stomach postion tools have been developed to describe where certain percentages of truck drivers position there knees and stomachs in various workspace arrangements. Separate equations describe the accommodation level for driver populations with male to female ratios of 50/50, 75/25, and a range from 90/10 to 95/5. These equations can be used as a design tool to locate the curves in vehicle space to describe the region behind which the given populations shin-knees, and stomachs would be located. Equations and curves are provided for both the left leg, which operates the clutch, and the right leg, which operates the accelerator.

Truck driver eye and head position tools have been developed to describe where certain percentages of truck drivers position there eyes and heads in various workspace arrangements. Separate equations describe the accommodation level for driver populations with male to female ratios of 50/50, 75/25, and a range from 90/10 to 95/5. These equations can be used as a design tool to locate the curves in vehicle space to describe the region behind which the given populations eyes and heads would be located. Equations and curves are provided for both the drivers eye and head in the side view. It has become increasingly apparent that there is a need for improved methods of accommodating truck drivers in heavy truck cab design. Currently, practices used in the automobile industry for passenger car design are utilized for the design of heavy trucks. These practices.

In many instances, automotive companies wish to create both a left-hand drive and a right-hand drive version of the same vehicle. When the vehicle has relatively low sales volumes, it is imperative to reduce investment costs wherever possible. One successful - if challenging - way is by producing the instrument panel system for both versions off the same tooling. This feat was accomplished in the case of the '97 Jeep® Wrangler, saving the company approximately $7 million.

To satisfy the objectives of Chrysler's new generation of compact vehicles, a unique front suspension system was created. This system has achieved an outstanding level of ride comfort while providing significant advantages in the basic vehicle packaging. The key to the system is the transverse torsion bar and bushings which serve the dual function of suspension spring and fore and aft restraint for the lower control arm. Producing this torsion bar in mass production required advances in both engineering and manufacturing technology.