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Glass fiber reinforced plastic of polyamide is applied as one of the materials used for the high strength exterior parts of a motorcycle, such as a rear grab rail or a carrier, to which both strength and good exterior appearance are required. However, Glass Fiber reinforced Polypropylene (PPGF), which is relatively inexpensive material, has a property that the contained glass fibers are prone to be exposed at the surface and, therefore, the requirements for good appearance are hardly met by using PPGF. In this study, Heat and Cool molding method (H&C molding) was employed to realize a cost reduction by using PPGF yet without applying painting process, and the established method was applied to mass production while fulfilling the requirements for a good exterior appearance. In H&C molding, the metal molds are heated up by steam and cooled down by water after molding.

Brake pad to rotor adhesion following exposure to corrosive environments, commonly referred to as “stiction”, continues to present braking engineers with challenges in predicting issues in early phases of development and in resolution once the condition has been identified. The goal of this study took on two parts - first to explore trends in field stiction data and how testing methods can be adapted to better replicate the vehicle issue at the component level, and second to explore the impacts of various brake pad physical properties variation on stiction propensity via a controlled design of experiments. Part one will involve comparison of various production hardware configurations on component level stiction tests with different levels of prior braking experience to evaluate conditioning effects on stiction breakaway force.

When using aluminum for vehicle body parts to reduce weight, the high pressure die casting (HPDC) is widely applied due to its adaptability to thin-wall products, near-net-shape castability, and short casting cycle time. Since a hollow construction is advantageous to increase stiffness of body parts, there has been a need of development of techniques for casting of hollow parts by HPDC. So far, hollow casting by HPDC has been realized for small parts using sand cores. When applying that method to large parts, however, it is necessary to increase filling speed. When the filling speed is increased, the core tends to break. In this project, we have developed a method to estimate changes of pressure distribution when filling molten metal by the casting simulation in order to analyze damages to the core. Through the analysis, we discovered occurrence of impulsive pressure waves.

Currently, there is a growing demand for application of plastic coverings for motorcycles in the market. Accordingly, decorative features for plastic coverings are increasingly important to enhance the attractiveness of exterior designs of those motorcycles. Under these circumstances, the magnetically formed decorative painting had been adopted to a mass-production model sold in Thailand in 2008. Magnetically formed decorative painting is a method in which the design patterns are formed by painting a material that contains flakes movable along with magnetic fields, while applying magnetic sheets in the ornamenting design shapes underneath the part being painted. It offers a three-dimensional appearance even though its surface has no protrusions or indentations. The degree of three-dimensionality on the paint surface appearance was defined as “plasticity” [1] (a term used in pictorial arts).

There are a couple of ways to manufacture aluminum cylinder blocks that have a good balance between productivity and abrasion resistance. One of them is the insert-molding of a sleeve made of PMC (Powder Metal Composite) by the HPDC (High Pressure Die Casting) method. However, in this method, cracks are apt to occur on the surface when the PMC sleeve is extruded and that has been a restriction factor against higher extrusion speed. The authors attempted to raise this extrusion temperature by eliminating the Cu additive process from the aluminum alloy powder in order to raise its melting point by approximately 50 °C. This enabled the wall of the extruded sleeve to be thinner and the extrusion speed to be higher compared to those of a conventional production method while avoiding the occurrence of surface cracks.

The new die cast (HPDC) wheel alloy has been developed using recycled aluminum to attain considerable reduction of energy at the time of material production to make large contribution to the reduction of CO2 emissions. The material for motorcycle body parts, especially for wheels, requires a sufficient elongation property. However, when recycled aluminum, which contains large amount of impurities, is used as main raw material, the intermetallic compounds crystalize out and the elongation property is deteriorated. Accordingly, we firstly made the investigations on the elements contained in a recycled aluminum and it was clarified that the elongation property was correlated to the shape of crystallized iron-based intermetallic compounds.

Gasoline includes various kinds of chemical species. Thus, the reaction model of gasoline components that includes the low-temperature oxidation and ignition reaction is necessary to investigate the method to control the combustion process of the gasoline engine. In this study, a gasoline combustion reaction model including n-paraffin, iso-paraffin, olefin, naphthene, alcohol, ether, and aromatic compound was developed. KUCRS (Knowledge-basing Utilities for Complex Reaction Systems) [1] was modified to produce paraffin, olefin, naphthene, alcohol automatically. Also, the toluene reactions of gasoline surrogate model developed by Sakai et al. [2] including toluene, PRF (Primary Reference Fuel), ethanol, and ETBE (Ethyl-tert-butyl-ether) were modified. The universal rule of the reaction mechanisms and rate constants were clarified by using quantum chemical calculation.

A common occurrence in computer aided design is the need to make changes to an existing CAD model to compensate for shape changes which occur during a manufacturing process. For instance, finite element analysis of die forming or die tryout results may indicate that a stamped panel springs back after the press line operation so that the final shape is different from nominal shape. Springback may be corrected by redesigning the die face so that the stamped panel springs back to the nominal shape. When done manually, this redesign process is often time consuming and expensive. This article presents a computer program, FESHAPE, that reshapes the CAD or finite element mesh models automatically. The method is based on the technique of volume morphing pioneered by Sederberg and Parry [Sederberg 1986] and refined in [Sarraga 2004]. Volume morphing reshapes regions of surfaces or meshes by reshaping volumes containing those regions.

At the early design stage it is easier to achieve impacts on the brake noise. However most noise analyses are applied later in the development stage when the design space is limited and changes are costly. Early noise analysis is seldom applied due to lack of credible inputs for the finite element modeling, the sensitive nature of the noise, and reservations on the noise event screening of the analysis. A high quality brake finite element model of good components’ and system representation is the necessary basis for credible early noise analysis. That usually requires the inputs from existing production hardware. On the other hand in vehicle braking the frequency contents and propensity of many noise cases are sensitive to minor component design modifications, environmental factors and hardware variations in mass production. Screening the noisy modes and their sensitivity levels helps confirm the major noisy event at the early design stage.

The mechanism of noise production in engine accessory drive belts was discussed. Applying geometric considerations to the transversal vibration of the belt, which is one cause of belt noise, the research showed that vibration of the belt is affected by fluctuations in the rotational speed of the crankshaft, and that the amplitude of the vibrations fluctuates cyclically. The cycle of this amplitude fluctuation is synchronous with engine speed, and for a 3-cylinder gasoline engine, its frequency is the (1.5*n)th engine rotation order. The spectrum pattern of belt vibration therefore shows components of the natural frequency±(1.5*n)th orders. The research demonstrated that at engine speeds at which the natural frequency±(1.5*n)th orders and the (1.5*n)th order frequencies, the engine excitation orders, are identical, multiple engine orders excite resonance in the belt, producing a high degree of belt vibration.

This paper illustrates a methodology in which complete material-manufacturing process cases for closure panels, reinforcements, and assembly are modeled and compared in order to identify the preferred option for a lightweight closure design. First, process-based cost models are used to predict the cost of lightweighting the closure set of a sample midsized sports utility vehicle (SUV) via material and process substitution. Weight savings are then analyzed using a powertrain simulation to understand the impact of lightweighting on fuel economy. The results are evaluated in the context of production volume and total mass change.

While the industry has recognized the value of modeling and code generation, the role of verification has taken a limited second tier role. Model Based Testing (MBT) is typically discussed in the context of automation of testing activities to eliminate the burden of generation and execution of tests. Unfortunately, this objective of effort minimization has skewed solutions away from using quality as a guiding metric. Alternatively, we have identified the simple objective of increasing the quality of testing practices and productivity of developers. In the following paper we introduce the integration of traditional software quality practices of functional, unit, and regression testing with the automated, model-driven world. This approach enables a quantitative approach to model driven software quality. The result is a robust technique that enables confident use of model-based development for production applications.

Laminated steel has been increasingly applied in automotive products for vibration and noise reduction. One of the major challenges the laminated steel poses is how to simulate forming processes and predict formability severity with acceptable correlation in production environment, which is caused by the fact that a thin polymer core possesses mechanical properties with significant difference in comparison with that of steel skins. In this study a cantilever beam test is conducted for investigating flexural behavior of the laminated steel and a finite element modeling technique is proposed for forming simulation of the laminated steel. Two production panels are analyzed for formability prediction and the results are compared with those from the try-out for validation. This procedure demonstrates that the prediction and try-out are in good agreement for both panels.

Managing (minimizing and optimizing) the total mass of a vehicle is recognized as a critical task during the development of a new vehicle, as well as throughout its production lifecycle. This paper summarizes a literature review of, and investigation into, the strategies, methods and best practices for achieving low total mass in new vehicle programs, and/or mass reductions in existing production vehicle programs. Empirical and quantitative data and examples from the automotive manufacturers and suppliers are also provided in support of the material presented.

Achieving optimum results and developing systems that are towards production intent is a challenge that the General Motors Sequel platform not only overcame, but also enhanced by providing an opportunity to achieve maximum integration of new technologies. Implementation of these new technologies during this project enabled us to understand the impact and rollout for future production programs to enhance performance and add features that will enable General Motors to make quantum leaps in the automotive industry. Presented are aspects, objectives and features of the Sequel's advanced Brake-By-Wire system as it migrates from concept towards production readiness. Also included in the paper are the objectives for system design; functional/performance requirements and the desired fault tolerance. The system design, component layout, control and electrical system architecture overviews are provided.

In GM R&D Powertrain/Engine Control Group, rapid prototyping controller (RPC) systems with Matlab/Simulink are used extensively to design, simulate and implement advanced engine control algorithms and models. However, those RPC systems use powerful microprocessors with large amounts of RAM contrary to engine control modules (ECM) in production vehicles. Therefore, a thorough analysis on the comparatively much more complicated algorithms and models cannot be performed during the research stage, since there are not enough tools to enable the smooth transition from Matlab/Simulink to the production type processor. The Real-Time Interface (RTI) Blockset for a production like microprocessor would close the transition gap between rapid prototyping controller systems and production type microprocessors by leveraging the power and popularity of Matlab/Simulink in control engineering world and automatic code generation tools.

Cylinder pressure data is so completely integral to the combustion system development process that ensuring measurements of the highest possible accuracy is of paramount importance. Three main areas of the pressure measurement and analysis process control the accuracy of measured cylinder pressure and its derived metrics: 1) Association of the pressure data to the engine's crankshaft position or cylinder volume 2) Pegging, or referencing, the pressure sensor output to a known, absolute pressure level 3) The raw, relative pressure output of the piezoelectric cylinder pressure sensor Certain cylinder pressure-based metrics, such as mean effective pressures (MEP) and heat release parameters, require knowledge of the cylinder volume associated with the sampled pressure data. Accurate determination of the cylinder volume is dependent on knowing the rotational position of the crankshaft.

A rapid prototyping controller (RPC) based, full-authority, diesel control system is developed, implemented, tested and validated on FTP cycle. As rapid prototyping controller, dSPACE Autobox is coupled with a fast processor based slave for lower level I/O control and a collection of in-house designed interface cards for signal conditioning. The base software set implemented mimics the current production code for a production diesel engine. This is done to facilitate realistic and accurate comparison of production algorithms with new control algorithms to be added on future products. The engine is equipped with all the state-of-the art subsystems found in a modern diesel engine (common rail fuel injection, EGR, Turbocharger etc.).

A case study on halfshaft design was presented to illustrate the application of axiomatic design principles in problem solving at General Motors. The halfshaft design was analyzed to identify design parameters to decouple insertion and retention forces. Design changes were made and implemented in production.

This paper describes the Human Factors (HF) research undertaken to support the new midgate incorporated in the Chevrolet Avalanche. This concept had several unique user interfaces not previously used in vehicle design and required several Human Factors studies to assess the usability of this concept. In addition, this paper discusses developing a protocol for conducting iterative Human Factors studies to assess the usability impact of product changes within the strict production program time lines.