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In this paper, loads acting on driveline components during an entire proving ground (PG) durability schedule are used to demonstrate the methodology of optimizing driveline performance reliability using both physical and computational methods. It is well known that there is an effect of driver variability on the driveline component loads. Yet, this effect has not been quantified in the past for lack of experimental data from multiple drivers and reliable data analysis methods. This paper presents the data reduction techniques that are used to identify the extreme driver performance and to extrapolate the short-term measurement to long-term data for driveline performance reliability. The driveline loading variability is made evident in the rotating moment histogram domain. This paper also introduces the concept for a simulation model to predict the driveline component loads based on a complete proving grounds schedule. A model-to-test correlation is also performed in this paper.

During the initial vehicle design phase and as the first prototypes are built, extensive on-board instrumentation and data acquisition is required at the proving grounds (PG). The data is used for various types of testing and analysis. During this phase of development very few parts and assembly components are available for physical test. The objective is to develop a component test for the truck box. This test can be run without suspension parts during the early stages of the vehicle development. A further objective is to correlate the test to FEA models and actual Proving Ground full vehicle test results.

Throughout its history, the automobile has served the utilitarian purpose of transportation quite well. However, until recently, vehicle occupants have had little else to do while proceeding from point "A'' to point "B.'' The phenomenal improvements in computing and communication technologies promise to evolve the driving experience. Like never before, new opportunities to make driving more efficient and engaging are becoming available. The challenge will be to develop the right combination of technology, safety, design and user interface that creates a product popular with customers.

This paper will provide an overview of the need, requirements, and constraints governing the development and application of polymer composites in automotive body components. It will discuss the efforts underway to lead and support the technology developments required for the cost-effective application of these new materials in mass-produced vehicles. The requirements and constraints of customer-driven, mass-produced, energy-efficient vehicles with uncompromised cost, capacity and performance, drive careful consideration of an injection-molded thermoplastic approach to a composite automotive body. Recent progress with this approach will be reported and some next steps examined.

An assessment of stamped part quality and launch readiness occurs at many intervals. This paper will focus on dimensional control activities that take place after Stamping Dies are constructed, but prior to producing the stamped parts. Die certification and die repeatability measurements have been performed at DaimlerChrysler and the results are documented. This die certification process provides an opportunity to uncover and resolve die machining issues with respect to the part math model or pre-engineered compensation model prior to producing parts. Additionally, the die repeatability process is performed to determine the ability of the die gaging to locate the incoming in-process material consistently. This paper will explain the die certification and die repeatability processes and share what we have learned. It will describe the processes, the tools, the participants, the sites, the benefits, and the measurement equipment.

In this paper, responses from a vehicle's suspension, chassis and body, are used to demonstrate a methodology to optimize physical test results. It is well known that there is a variability effect due to an increase of wheel unsprung mass (due to loads measurement fixturing), tire pressure, speed, etc. This paper quantifies loading variability due to Wheel Force Transducer (WFT) unsprung mass by using a rainflow cycle counting domain. Also, presents a proving ground-to-test correlation study and the data reduction techniques that are used in road simulation test development to identify the most nominal road load measurement. Fundamental technical information and analytical methodology useful in overall vehicle durability testing are discussed. Durability testing in a laboratory is designed to correlate fatigue damage rig to road. A Proving Ground (PG) loading history is often acquired by running an instrumented vehicle over one or more PG events with various drivers.

Even with the rapidly evolving computational tools available today, suspension design remains very much a black art. This is especially true with respect to road cars because there are so many competing design objectives. In a racecar some of these objectives may be neglected. Even still, just concentrating on maximizing road-holding capability remains a formidable task. This paper outlines a procedure for establishing suspension parameters, and includes a computational example that entails spring, damper, and anti-roll bar specification. The procedure is unique in that it not only covers the prerequisite vehicle dynamic equations, but also outlines the process that sequences the design evolution. The racecar design covered in the example is typical of a growing number of small open wheel formula racecars, built specifically for American autocrossing and British hillclimbs.