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Rapid Prototyping, Fabrication and Tooling is a process that blends a series of technologies (machines, tools, and methods) capable of generating physical objects directly from a CAD database. The process dramatically reduces the time spent during product development by allowing for fast visualization, verification, iteration, optimization, and fabrication of parts and tools. Many new techniques of tooling have been and are being developed by using rapid fabricated parts. These are having a dramatic impact on both timing and costs throughout the automotive industry. One area that these methods can be utilized to their full potential is motorsports. Of particular interest is the growing use of bridge tooling to provide first article through production intent parts that promote cost effective changes.

Computers have made an impact in nearly every facet of professional racing. Most of the progress in the coming years will come as the tools that are in common use today, control systems, measurement tools, CAD, CAM, CFD, and the like, evolve and mature. This Paper argues that true innovation in the near future will come in the form of tools that help improve the two dominant facets that make a car faster - the ability of the driver and the intuition of the race engineer. The paper is divided into two parts, the first looks at the subject of information in racing1 and the second how this information infrastructure provides fertile ground for innovation with respect to driver and race engineer understanding.

Designing for optimal performance across a variety of situations involves compromise decisions. Through the investigation of a two-variable optimization of a vehicle for two different “races” the importance of this compromise design is underscored. The use of Pareto-minimal solution techniques, borrowed from game theory, aid in the design process by limiting the number of possible compromise designs, highlighting which solution applies for a given situation and providing some insight to the sensitivity of the design.

The design process followed for the design of a Formula-SAE engine is described. Current rules and past competition results were used to constrain the powertrain system. This system consists of the intake system, engine, transaxle, and exhaust system. Intake restrictor design is discussed. Options were compared using a friction analysis. Computer simulations were used to develop brake power and torque graphs. An analysis of thrust vs velocity graphs with those torque curves have been developed. This process serves as a useful tool in understanding the tradeoffs such as the number of cylinders, piston speed, cylinder size, etc; and how they can be used to develop a competitive package.

A unique differential assembly was needed for the Lawrence Technological University (LTU) SAE Formula race car. Specifically, a differential was required that had torque sensing capabilities, perfect reliability, high strength, light weight, the ability to withstand inertia and shock loading, a small package, no leaks, the ability to support numerous components. In that regard, an existing differential was selected that had the torque sensing capabilities, but had deficiencies that needed to be fixed. Those deficiencies included the following: Differential unit was over 4 kg unmounted, with no housing. This was considered too heavy, when housed properly. Bearing surface was provided on only one end of the carrier. This design provides insufficient bearing surface to support either the differential housing or half-shafts The internal drive splines integral to the case are not optimized for a perpendicular drive/axle arrangement, such as, a chain drive.

A computer model was developed to help predict injury potential to race drivers during crash events. The model is based on MADYMO3D, a multi-body simulation software. The main input to the model is the 3-D crash pulse as measured by an impact sensor implemented jointly by Ford and CART, Inc. The race driver is represented by the HYBRID-III dummy data set. Dynamic tests were conducted to determine the restraint system and helmet force-deformation characteristics. The model output consists of estimates of the Head Injury Criterion (HIC), head and chest accelerations, neck loads and moments, and lumbar loads. The model was exercised using seven crash pulses from the 1997 CART season and results were compared with reported injuries.

There are a number of benefits from Ford Motor Company's participation in motorsports. This paper will describe how an engineering team developed a CAE process to assist in the design of a race car to meet impact requirements, with the technology transfer benefit of improved impact performance of composite structures in passenger cars. In 1997/98, a CAE process was developed and applied in the design and test of Formula One race car composite impact structures. For this particular engineering effort, a Ford proprietary software program, COMP-COLLAPSE, was the primary analysis tool that was utilized to successfully predict impact performance. As a result, COMP-COLLAPSE was used extensively in the design of race car composite impact structures. There were two beneficiaries from this effort: Race Vehicles: Improved vehicle impact performance as well as design improvement in crush efficiency, packaging, weight, and manufacturing.

It is common practice for countries to have general access “workhorse” vehicles which are subject to one set of limits and limited access vehicles subject to a different and higher set of limits. The first option for improving productivity is usually a simple combination representing economies of scale using existing trailer units. An alternative to this practice, already being adopted in most countries, is the use of innovative vehicles. As part of nations' size and weight systems, processes for reviewing and changing limits are becoming more selective and are using elements of performance-basing. There is persuasive evidence from a number of countries that current size and weight systems are extremely effective for the simple considerations of vehicle width and height, and for pavement wear. A misplaced emphasis is placed on overall length in some countries and low-speed offtracking is a well-recognized, but very poorly controlled, performance measure.

The U.S. Department of Transportation's Comprehensive TS&W Study addressed the safety impacts of potential changes to TS&W limits from two perspectives: (1) the assessment of crash information and exposure data (vehicle miles traveled), and (2) the evaluation of stability and control performance of several truck configurations in terms of static roll stability, rearward amplification, and load transfer ratio. This paper addresses the analytical approach used to evaluate safety impacts from the latter perspective. The vehicle performance measures were estimated using simulation models. Several vehicle parameters were varied in a large parametric analysis for use in the study.

This paper reports on the analysis of mechanisms concerning the engine exciting force and the rotational couple of forces. Because the new V10 engine has the biggest power and displacement which is 441kw and 30 litters respectively, its exciting force of 2.5th and 5th orders are very large. On the other hand, as the V-bank angular is 80 degrees, the additional 1st order yawing vibration is also occurred by the generation of the rotational couple of forces. So, the optimum design is needed to reduce these vibrations by the frequency response analysis when these forces are added to the engine crank shaft. Finally, the vibration level could be reduced much lower than the lower-powered engine by the optimum design of engine mounting by using the FEM and the adoption of the new mechanism for the cancellation of a rotational couple of force.

The SAE J1739 standard for failure mode and effects analysis is modified and extended to the analysis of software designs. Two techniques are presented for using a software DFMEA (design failure mode and effects analysis) formalism: 1) using analysis and design tools and 2) using actual code. With a DFMEA, the software engineering team can anticipate software problems, can improve test design, can analyze software for potential safety and hazard issues, and can document analysis, design, and code walk-throughs. Output analysis is used for the following: data context, data flows, software and hardware interfaces, and various levels of software configuration categories in order to systematically develop the software DFMEA. Also examined is the use of the software DFMEA with other techniques that are frequently used to study software safety issues; for example, fault trees and flow diagram methods.

This research project examined truck size (dimensions) and weight regulation in other countries, worldwide, to identify size and weight regulations that are based on standards of truck performance. The study revealed that some countries have begun to account for differences in vehicle performance in their size and weight regulations. The potential U.S. role of 24 noted performance-based standards was examined comparing enforcement issues versus the benefits associated with each noted standard and groups of standards. Based on a preliminary analysis, the analysis revealed that the benefits attributable to 12 of the noted standards may be equal to or greater than their enforcement issues, and thus may be more easily implemented into the U.S. Truck Size and Weight Framework.

This paper outlines Pi Technology's approach to testing high-reliability automotive software. Based on data collected during an engine controller development, it discusses the value of different types of testing at various stages of the design process and when errors are found. The team structure used for embedded systems is discussed to provide the context in which software development occurs.

Considerable debate has focused on the safety of commercial heavy trucks, and particularly on the question of whether allowing truck sizes and weights to increase would degrade safety. Efforts to answer that question have centered on two approaches, crash data analyses and, comparative analyses of the safety-related engineering performance capabilities of various truck configurations. This paper summarizes recent crash data analysis work, while a companion paper to this one, (“Vehicle Stability and Control Research in the U.S. Comprehensive Truck Size and Weight Study, SAE Paper No. 982819), addresses what can be learned from engineering analysis of this issue. Together, these two approaches yield insights into the potential safety outcomes that could result if truck size and weights requirements were changed. Some outcomes might not be positive. This paper concludes with a discussion of the conditions under which positive outcomes might be possible.

This paper describes the analytical framework underlying the U.S. Department of Transportation's (DOT's) 1998 Comprehensive Truck Size and Weight (TS&W) Study. The purpose of the Study is to provide a policy architecture within which the Nation's current body of TS&W laws may be assessed. The analytical framework provides a structure for assessing the impact of alternative TS&W policy options. Data and analytical tools have been developed to evaluate critical impact areas: highway agency costs (pavement preservation, bridge protection and geometric requirements), safety of the system, environmental quality, energy consumption, traffic flow, rail and shipper costs. The DOT identified a set of illustrative core scenarios for initial evaluation. Scenarios were specified using a building block approach which includes configuration, highway network and geographic options.

This paper will demonstrate an integrated approach to product development and documentation using IQ-FMEA quality software1. This approach begins with the creation of a system structure and assigning functions or requirements to these structural elements; the structure is subsequently expanded through the incorporation of potential failures which are linked to these functional requirements. This expanded system provides the necessary inputs for the development of structurally-linked cause-effect function and failure networks which can be transferred directly and automatically into Design Failure Modes and Effects Analysis (DFMEA) forms. Data can easily be selected from DFMEAs or underlying structures to create Process FMEAs (PFMEAs) using Drag & Drop technology.

The modal-scaling technique is just a treatment of normal mode results to find stresses in an object responding in its global modes under given boundary and input environment. It takes the stresses from a normal mode run and scales them according to reaction forces either measured in testing or obtained otherwise at the boundaries. This technique is a better alternative and supplement to the traditional quasi-static g loading technique in two aspects. It finds stresses in actual global response modes, while the quasi-static g loading technique finds stresses in approximated global response modes simulated by applying a uniform g loading throughout the object. Additionally, it can find stresses beyond the three principal global response modes (roll, pitch, and bounce) that the quasi-static g loading technique is typically not capable of.

This paper explores the costs and benefits of using graphics as part of the embedded systems modeling and simulation effort. It defines the term “simulation graphics” and positions it in the context of the overall development process. Finally, it offers guidelines for how and when to use graphics to optimize the cost- benefit ratio.

The analysis of automotive circuits presents several unique challenges to design and test engineers. One of these challenges is prevalence of multiple technologies in automotive systems. This limits the use of simulation on these systems, since most simulation products are effective only in one technology. This paper demonstrates how a mixed-technology simulator can be applied to automotive systems, both for design analysis and testing. The Saber simulator was used because of its unique capabilities in the simulation and analysis of mixed-signal and mixed-technology systems.

An oxidation catalyst for diesel engines has been tested in the North American market with proven satisfactory initial performance and durability tests of vehicles but has yet to be evaluated by its bench durability tests due to shorter test duration. Therefore, the oxidation catalyst, durability tested by vehicle and bench, was subjected and the test data were analyzed to clarify its degradation mechanism and set up outlooks for evaluation of its durability by bench tests.