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The present paper describes the system design for the Clear Vision auto defog system and the improvements made to the Integrated Dew Point and Glass Temperature (IDGT) sensor. The Clear Vision auto defog system has been implemented on a 2000 Cadillac DeVille. Preliminary validation tests demonstrate satisfactory performance.

A steering wheel is an indispensable component in an automobile. Although the steering wheel was invented about one hundred years ago and its structure has since become more and more complex with numerous innovations, documented analysis on steering wheel performance is very limited. Today, a steering wheel is not only a wheel that controls where your car goes; it also plays an important role in a vehicle occupant protection system. Therefore, many requirements have to be met before a steering wheel goes into production. With the development of computational mechanics and increasing computer capability, it has become much easier to evaluate the steering wheel performance in a totally different way. Instead of running prototype tests, steering wheel designs can be modeled virtually in various scenarios using finite element analysis, thus facilitating the development cycle.

Currently in the automotive industry, most software source code is manually generated (i.e., hand written). This manually generated code is written to satisfy requirements that are generally specified or captured in an algorithm document. However, this process can be very error prone since errors can be introduced during the manual translation of the algorithm document to code. A better method would be to automatically generate code directly from the algorithm document. Therefore, the automotive industry is striving to model new and existing algorithms in an executable-modeling paradigm where code can be automatically generated. The advent of executable models together with automatic code generation should allow the translation of model to code to be error free, and this error-free status can be confirmed through testing. A three-stage process is presented to functionally verify the model, functionally verify the automatically-generated code, and structurally verify the code.

Adhesive joining is a common autobody subassembly technique especially for outer panels, where visible spot welding is objectionable. To accommodate mass production with the use of certain adhesives very high thermal gradient usually exists, which may result in panel dimensional distortion and variation. The temperature distribution over location and over time are monitored, and its impact to panel dimension is investigated. Experimental results on the effect of the distance between panel and induction coil on the panel temperature is obtained. The thermal induced shape distortion is simulated with a simplified FEA model. The approach to improvement of the induction curing process is discussed.

Life cycle benefits of a chrome-free sealing wash were evaluated. Material consumption, disposal costs, water pretreatment, waste water treatment and product performance were used to compare a chrome-free product to traditional washes. Acquisition costs and vehicle weight impacts were also considered. The direction of domestic and international regulatory initiatives will play a significant part in the application of this study=s findings. The paper discusses the factors and decision process that led to the trial of chrome free rinse in a vehicle assembly plant and the results of this test. Durability testing was performed with current and evolving primer systems. Equivalent durability was shown with multiple supplier/multiple primer process combinations. The study indicated that chrome-free sealing wash would yield a small cost savings and a minor reduction in weight with equal performance to the current chrome containing process.

A new optimal control strategy for dealing with braking actuator failures in a vehicle equipped with a brake-by-wire and steer-by- wire system is described. The main objective of the control algorithm during the failure mode is to redistribute the control tasks to the functioning actuators, so that the vehicle performance remains as close as possible to the desired performance in spite of a failure. The desired motion of the vehicle in the yaw plane is determined using driver steering and braking inputs along with vehicle speed. For the purpose of synthesizing the control algorithm, a non-linear vehicle model is developed, which describes the vehicle dynamics in the yaw plane in both linear and non-linear ranges of handling. A control allocation algorithm determines the control inputs that minimize the difference between the desired and actual vehicle motions, while satisfying all actuator constraints.

Biodiesel has become a major alternative fuel for automotive applications demonstrated by its increasing presence in the market place. This paper summarizes test results for recently collected retail samples of biodiesel (B100) and blended biodiesel from the U.S. and the European Union to provide a snap shot of current fuel quality in each market. Properties reported included biodiesel content, oxidation stability, acid number, water, metals, and glycerin content. For B100, only total contamination measured as particulates was significantly lower for the EU than the U.S. For blends containing up to 5% biodiesel, there were significant differences between the U.S. and the EU in sulfur content, oxidation stability (Rancimat), cetane number, and cloud point. For blends higher than B5, present only in the U.S., pump labeling was found to be a poor indicator of biodiesel content.

The General Motors Allison Two-Mode compound split parallel hybrid EP system for transit buses has been in production for over three years, accumulating over 20 million fleet miles. During this period of operation, extensive fuel economy analysis has been performed over multiple use cycles in multiple locations. This paper describes the in-use fuel economy results, as well as the hybrid system mode operations, the component utilization, and the controls improvements to maximize the hybrid fuel economy. Actual in-use data will be presented from individual vehicles, as well as the fleet averages encompassing a broad range of duty cycles. A chassis dynamometer testing results are discussed as an alternative evaluation method.

A new turbocharged 2.2 liter engine has been developed by Chrysler Corporation. It is derived from the Chrysler 2.2 liter naturally aspirated four cylinder powerplant. A number of new and redesigned components were required to yield a durable, high performance production engine. The compact installation includes a watercooled turbocharger and multi-point fuel injection. Electronic controls are used to satisfy the demanding performance and durability requirements unique to the turbocharged powerplant.

As an essential dimension of product harmony and craftsmanship, product sound quality has drawn increasing attention from customers in recent years. To meet this customer requirement, Delphi Corporation has been taking a proactive role in understating customer preferences, improving designs, and developing a sound quality knowledge base for this purpose. This study investigates the characteristics of the glovebox closure sound that affects the customer's perception of the product harmony and craftsmanship. Previous research has indicated that the perceived closure sound quality is affected by the spectral balance, the occurrence of multiple impulses, and the duration of the closing event. The primary goal of this study is to explore how these parameters affect the perception of glovebox sounds and to what extent. A jury evaluation was conducted with a sequence of glovebox closure sounds, which were derived from an existing recording.

Some Electronic Throttle Control (ETC) Air Control Valves (ACV) on automotive internal combustion engines are susceptible to icing of the throttle valve. Ice formation can result in an increase in torque required to open or close the valve. Laboratory studies were conducted to improve the understanding of throttle valve icing on electronic throttle control valves with both aluminum and composite (plastic) bodies over various bore sizes (4 cylinder to 8 cylinder engines). Study results indicated that ice compression at the bore and valve gap, not ice adhesion, is the major contributor to the ETC-ACV icing phenomenon. In addition, testing of parts with various bore sizes, orientations and surface cleanliness resulted in further understanding of the icing issue.

The rheological behavior of automatic transmission fluids (ATF) ranges from moderately shear-thinning to Newtonian. However, no commercially available ATFs are known to display shear-thickening behavior. A theoretical investigation was performed to determine if any advantages could be derived from the use of shear-thickening ATF in automatic transmission components and subsystems. A series of theoretical shear-thickening, shear-thinning, and Newtonian fluids were modeled by a power law function and compared to a reference shear-thinning ATF in simplified representations of transmission components and subsystem geometries. The results indicate that a shear-thickening ATF with zero shear viscosity, infinite shear viscosity, and power of 417 mPa-s, 6.23 mPa-s, and 1.03(dimensionless), respectively, displays optimized behavior with respect to the reference shear-thinning ATF.

This paper presents the results of the design and development work on variable inlet guide vanes (VIGV) for use in the ERDA Upgraded Automotive Gas Turbine Engine. The feasibility of the concept of VIGV augmentation was carried out on ERDA Baseline engine hardware in compressor rig and complete engine testing. Included in the paper are discussions of this VIGV design philosophy, development logic and test results, and the critical areas of gas generator compressor and turbine matching combined with variable-nozzle power turbine and vehicle matching.

An assessment of Body-In-White quality and launch preparedness occurs at many intervals. This paper will focus on dimensional control activities that take place during the first pre-production pilot phase known as P0. (P-zero occurs approximately 35 weeks before volume production.) Two Process Assurance Body Build Systems (Tooling Build and Plate Build) have been used at Chrysler and the results have been documented. The Plate Build and Tooling Build activities provide the opportunity to uncover and resolve Product Design and Part Quality Issues. In addition, the Tooling Build process has proven to be an objective method of identifying and correcting tooling, gaging and process issues during the P0 Vehicle Build Program.

Electro-mechanical brakes (EMBs) are emerging as a new approach to enhance brake system features as well as braking performance. This paper takes a fresh look at the switched reluctance (SR) drive as a possible prime mover technology for EMB applications. The switched reluctance motor has attractive potential, in view of its robustness, dynamic bandwidth and fault tolerance. An overall assessment of the approach is made based on bench performance of a prototype EMB caliper with an SR drive executing typical braking patterns. It is shown that the SR motor can provide the required overall brake actuator performance. Various implementation options are examined to lower cost, with particular focus on electronic design, control algorithms and motor position sensing.

Using standard industry tests, the oxidation stability of General Motors current factory-fill automatic transmission fluid (ATF) was compared to that of a proposed factory-fill ATF to be introduced for the 1995 Model Year. Full-scale transmission tests and Aluminum Beaker Oxidation Tests run at various temperatures showed that a proposed factory-fill fluid is substantially more resistant to oxidation than the current factory-fill ATF. Using Total Acid Number increase (Δ-TAN) as the measure of oxidation, a minimum of 35% improvement was obtained with a proposed factory fill. This improvement at least doubles the time to “perceived fluid failure” (Δ-TAN = 2.5).

This study examines the effectiveness of gaseous oxygen at preventing embrittlement in steel associated with exposure to gaseous hydrogen under static loading conditions. Notched C-ring samples machined from 4340 steel and heat treated to HRC 51-53 were used to test the neutrality of an oxygen-hydrogen gas mixture similar to that which may be used as a generant in an air bag inflator. The 29 percent oxygen to hydrogen gas ratio of the gas mixture was found to be sufficient to protect the steel from hydrogen embrittlement under static loading conditions. This would indicate that any steel with a hardness of HRC 51 or lower would be safe to use in gas-based air bag inflators containing a oxygen to hydrogen gas ratio of 29 percent or higher.

Under a contract which began in November 1972, Chrysler Corporation has been conducting an automotive gas turbine improvement program for the Division of Transportation of the Energy Research and Development Administration. The final task of this program is to design, build, and demonstrate an Upgraded Engine. The design been accomplished and is described in this paper. It utilizes a number of improvements developed and verified on the Chrysler Sixth Generation “Baseline” engines, e.g. variable inlet guide vanes, water injection, ceramic regenerators, an integrated electronic control system, a free-rotor arrangement, a low emissions fixed geometry burner, and linerless insulation. Aerodynamic details to meet higher efficiency component specifications were provided by NASA Lewis. The design also incorporates a gas bearing on the rotor and improvements in arrangement and mechanical design.