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A time-efficient throttle flow data collection method is described. It uses a sonic nozzle flow bench to measure air flow as a function of throttle angle and pressure in a manner analogous to on-engine dynamometer throttle flow characterization. Opening each sonic nozzle combination, then recording throttle downstream pressure and computed nozzle flow allows data to be taken in a fraction of the time normally needed. Throttle flow modeling considerations are then discussed.

Blow moulding is one of the most important polymer processing methods for producing complex thermoplastic automotive parts. Contrary to injection molding, little attention has focused on process control and simulation of blow molding processes. Yet, there are still several problems that affect the overall success of forming these parts. Among them are thermally induced stresses, relevant shrinkage and part warpage deformations caused by inappropriate mold design and/or processing conditions. Tolerance issues are critical in automotive applications and therefore part deformation due to solidification needs to be controlled and optimized accordingly. The accurate prediction tool of part deformation due to solidification, under different cooling conditions in automotive formed parts, is important and highly suited for part designers to help achieve an efficient production.

On current competitive scenario for road load transportation in Brazilian market, the operational costs should be reduced as much as possible. The suspension system commonly used on road commercial trucks is based on leaf spring use and Hotchkiss concept for axle locating devices. The use of leaf springs without bolt attachment eyelets are still common for rear suspension systems. When using the leaf spring with direct contact to the brackets, wear plates are placed between them to work as wear elements due to the friction between the parts. The friction will cause wear on the parts, and the wear plate is designed to suffer the damages of this friction instead of the leaf spring, being the cheapest element and can be easily replaced. When the system works on a severe contamination environment with high levels of grit and dirt, the degradation of the parts are accelerated.

As part of a continuing Ford Motor Company program to improve the seating packages of production cars, a simplified in-plant method was developed to check seating variations in production vehicles. The method also provided information helpful in determining causal factors when any irregularities were found. Equipment necessary for checking was designed to be easily transported to any site.

It is generally accepted that all postures obtained from motion capture technology are realistic and accurate. Physical props are used to enable a subject to interact more realistically within a given virtual environment, yet, there is little data or guidance in the literature characterizing the use of such physical props in motion capture studies and how these effect the accuracy of postures captured. This study was designed to evaluate the effects of various levels of physical prop complexity on the motion-capture of a wide variety of automotive assembly tasks. Twenty-three subjects participated in the study, completing twelve common assembly tasks which were mocked up in a lab environment. There were 3 separate conditions of physical props: Crude, Buck, and Real. The Crude condition provided very basic props, or no props at all, while the Buck condition was a more elaborate attempt to provide detailed props. Lastly, the Real condition included real vehicle sections and real parts.

Wavelets are a powerful mathematical tool used to multi-resolution time-frequency decomposition of signals, in order to analyze them in different scales and obtain different aspects of the information. Despite being a relatively new tool, wavelets have being applied in several areas of human knowledge, especially in signal processing, with emphasis in encoding and compression of image, video and audio. Based on a previous successful applications (FRAZIER, 1999) together a commitment to quality results, this paper evaluates the use of the Discrete Wavelet Transform (DWT) as an compression algorithm to reduce the amount of data collected in road load signals (load history) which are used by the durability engineering teams in the automotive industry.

Over the past five years, the US Automotive Materials Partnership (USAMP) has brought together representatives from DaimlerChrysler, General Motors, Ford Motor Company and over 40 other participant companies from the Mg casting industry to create and test a low-cost, Mg-alloy engine that would achieve a 15 - 20 % Mg component weight savings with no compromise in performance or durability. The block, oil pan, and front cover were redesigned to take advantage of the properties of both high-pressure die cast (HPDC) and sand cast Mg creep- resistant alloys. This paper describes the alloy selection process and the casting and testing of these new Mg-variant components. This paper will also examine the lessons learned and implications of this pre-competitive technology for future applications.

Advances in digital and analog electronics have drastically changed car radio circuitry. Improvements in miniaturization of electrical and mechanical components have radically altered their size and styling. Computer modeling of the vehicle's interior environment has optimized car radio acoustics. It seems that the list of modern break-throughs is never ending. It is the intent of this paper to show that many of the technical marvels of today's car radios were first applied years, even decades, ago. From those early concepts, and their current revivals, a projection into the future of automobile radios will be made. As previously mentioned [1]: “If history teaches anything, it teaches the potential for repetition.”

Recently, control of the gas-exchange process has come into focus as a critical element of the development process for internal combustion (IC) engines. The information learned in various engine development organizations worldwide has recently been put into practice via the introduction of many variable valve control strategies. The intention of these strategies ranges from simple enhancement of volumetric efficiency to completely controlling the combustion process at various engine speeds. The challenge to engine designers is mainly to reduce the relatively high masses of the valve actuating elements while increasing the stiffness to positively affect the dynamic behavior of the valve actuation system. Other benefits of a light-weight valve train is the reduction of the required energy to displace the valve element, which results in a more compact (lighter) cylinder head construction.

Until recently, tool & die making was a very traditional industry, relying on extensive know-how accumulated over decades of practice. Essentially, it remained a two stage-process: engineering/manufacture, followed by tryout/productionization. Improvements focused on engineering and production methods, but tryout remained the exclusive domain of the die maker. At last, advances in computer modeling methods and the adoption of aggressive lean management principles have brought transformational changes to the tryout phase. At the same time, new safety and weight imperatives have increased the penetration of advanced materials, whose formability characteristics are quite different from mild steels. This paper will explore how these advanced materials affect this transformation.

Due to the challenges in quantifying hand loads in manufacturing environments it is often assumed that the load is evenly distributed between the hands, even when handling parts with non-uniform mass distribution. This study estimated hand loads for six female subjects, when handling a custom part in 8 different configurations (2 weights, 4 CofM locations). The calculated hand loads varied from 20 to 50% of the weight being handled. The magnitude of asymmetrical hand loading depended on both the part orientation and the location of the CoM. Based on this study the knowledge of part weight, CofM location and hand positioning will allow the users of digital human models to perform more realistic and reliable task analysis assessments as the force distributions will be more representative of the actual loading rather than simply assuming the load is evenly distributed between the hands.

While SAE double inverted flares have been in use for decades, leaking joints continue to be a problem for OEMs in production settings consuming time and energy to detect and correct them before releasing vehicles from the assembly plant. It should be noted that this issue is limited to first-time vehicle assembly; once a flared brake tube joint is sealed at the assembly plant it remains sealed during normal customer usage. From their inception through the late 1980s most brake tubes have been 3/16″ nominal diameter. With the advent of higher flow requirements of Traction Control and Yaw/Stability control systems, larger tubes of 1/4″ and 5/16″ size have also been introduced. While it was known that the first-time sealing capability of the 3/16″ joint was not 100%, leakers were generally containable in the production environment and the joint was regarded as robust.

The performance of a vehicle’s Automatic Speech Recognition (ASR) system is dependent on the signal to noise ratio (SNR) in the cabin at the time a user voices their command. HVAC noise and environmental noise in particular (like road and wind noise), provide high amplitudes of broadband frequency content that lower the SNR within the vehicle cabin, and work to mask the user’s speech. Managing this noise is a vital key to building a vehicle that meets the customer’s expectations for ASR performance. However, a speech recognition engineer is not likely to be the same person responsible for designing the tires, suspension, air ducts and vents, sound package and exterior body shape that define the amount of noise present in the cabin. If objective relationships are drawn between the vehicle level performance of the ASR system, and the vehicle or system level performance of the individual noise, vibration and harshness (NVH) attributes, a partnership between the groups is brokered.

Traditionally, door seals are designed to achieve good wind noise performance, water leakage and door closing effort in a vehicle design and development process. However, very little is known concerning the effect of door seal design on vehicle squeak and rattle performance. An earlier research work at Ford indicates a strong correlation between the diagonal distortions of body closure openings (in a low frequency range 0 - 50 Hz) and overall squeak and rattle performance. Another research at Ford reveals that relative accelerations between door latch and striker in a low frequency region (0 - 50 Hz) correlate well with door chucking performance. The findings of this research work enable engineers to assess squeak and rattle and door chucking performance using vehicle low frequency NVH CAE models at a very early design stage.

Ported shroud compressor covers recirculate low momentum air near the inducer blade tips, and the use of these devices has traditionally been confined to extending the low-flow operating region at elevated rotational speeds for compressors on compression-ignition (CI) engines. Implementation of ported shrouds on compressors for spark-ignition (SI) engines has been generally avoided due to operation at pressure ratios below the region where ported shrouds improve low-flow range, the slight efficiency penalty, and the perception of increased noise. The present study provides an experimental investigation of performance and acoustics for a SI engine turbocharger compressor both with a ported shroud and without (baseline). The objective of implementing the ported shroud was to reduce mid-flow range broadband whoosh noise of the baseline compressor over 4-12 kHz.

Technical Standards are essential for the expanded use of any engineering material. The Society of Automotive Engineers (SAE) Iron and Steel Castings Committee has been reworking existing, (and issuing new), standards for automotive iron and steel castings. This paper will review the status of the SAE standards for Ductile Iron, Austempered Ductile Iron (ADI), Compacted Graphite Iron (CGI) and high Silicon-Molybdenum (Si-Mo) Ductile Iron, Gray Iron and Steel Castings. The SAE Standards, (and draft standards), will be critically compared to those for ASTM and ISO. Salient differences in the standards will be discussed and implications to design engineers will be addressed. Comparisons to other, competitive materials (and their standards) will be made.

The aerodynamic development and characteristics of a four-passenger advanced concept automobile are described. An overview of the areas of the vehicle design which were dealt with to obtain a drag coefficient value of 0.153 is provided. The interior packaging philosophy is outlined which led to the potential for packaging four to six passengers within an extremely low drag automobile. Parametric shape studies of the major surface design elements are documented from the contributing development testing. The particular design treatments adopted and the rationale behind the choice of design are examined for each of the aerodynamically-sensitive areas of the vehicle. Examinations of the unique solutions to vehicle cooling, ramp and curb clearance, front wheel skirting and vehicle attitude are presented. Full scale wind tunnel data is shown for the configurations examined and vehicle stability parameters compared with conventional vehicles.

Globalization in the automotive industry has resulted in a tremendous competitive advantage to those companies who can internally communicate ideas and information effectively and in a timely manner. This paper discusses one such effort related to objectively testing vehicles for steering and handling characteristics by implementing standard test procedures, data acquisition hardware and analysis methods. Ford Motor Company's Vehicle Dynamics Test Section has refined a number of test procedures to the point that, with proper training, all design and development engineers can quickly acquire, analyze and share test results. Four of these procedures and output are discussed in detail.

In this paper, a systems engineering approach is explored to evaluate the effect of design parameters that contribute to the performance of the embedded Automatic Speech Recognition (ASR) engine in a vehicle. This includes vehicle designs that influence the presence of environmental and HVAC noise, microphone placement strategy, seat position, and cabin material and geometry. Interactions can be analyzed between these factors and dominant influencers identified. Relationships can then be established between ASR engine performance and attribute performance metrics that quantify the link between the two. This helps aid proper target setting and hardware selection to meet the customer satisfaction goals for both teams.

This paper will discuss the vehicle top-down design approach that includes the non-linearity and sub-system interactions such as tire and road, (left and right) interaction between two or more parts connected by bushings, springs, bolts, stabilizer-bar, etc… The proposed method would allow for the inclusion of realistic boundary conditions and proper load simulation, and it would provide the ability to visualize and evaluate dynamic structural phenomena and complex component interaction. This approach would also facilitate the evaluation of design changes that may affect load propagation and/or load magnitude. All of the advantages of the sub-system analysis method mentioned above would allow for a greater understanding of the sub-system as a whole and help correctly identify the design requirements needed for the individual components that make up such chassis subsystems.