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In automotive infotainment systems, multiple types of digital audio signals are usually present. Some come from internal sources, such as a CD or USB stick, and some come from external sources, such as an internet stream or digital radio. These sources usually have different sample-rates, and may also be different from one or more system sample-rates. Managing and transporting these signals throughout the system over different sample-rate domains require detailed upfront architecture analysis and correct system design to ensure signal quality is maintained to the desired level. Incorrect design can add significant user-perceivable noise and distortion. This paper examines the key analysis factors, the effects of poor design and the approaches for achieving robust signal handling and ensuring desired signal quality.

In this paper, an analytical procedure for prediction of shell radiated noise of air induction systems (AIS) due to engine acoustic excitation, without a prototype and physical measurement, is presented. A set of modeling and simulation techniques are introduced to address the challenges to the analytical radiated noise prediction of AIS products. A filter seal model is developed to simulate the unique nonlinear stiffness and damping properties of air cleaner boxes. A finite element model (FEM) of the AIS assembly is established by incorporating the AIS structure, the proposed filter seal model and its acoustic cavity model. The coupled acoustic-structural FEM of the AIS assembly is then employed to compute the velocity frequency response of the AIS structure with respect to the air-borne acoustic excitations.

First LED headlamps will be released into the market in 2007. Special permissions allow this introduction although the official regulation is still under discussion in ECE. The LED technology for front lighting has entered into a new phase from theoretical, prototype status to real and practical applications. Additionally in Europe the legislation, which is under preparation, defines LED modules with one or more LED chips in a row which should be replaceable. With this boundary conditions headlamp suppliers needs to balance between an attractive and innovative styling, demanded by car manufacturers and the light performance to gurantee good visibility at night. The paper describes the methods how to design an LED headlamp with high efficiency by keeping in mind the parameters: packaging, weight, styling and light perfromance. Results with specific design proposals are shown.

Light Emitting Diodes (LEDs) are fast becoming the preferred light sources for automotive lighting applications. They emit light at cone angles equal (hemispherical) or less (conical) than 2Π radians. One way for efficiently collecting and collimating light from LED light sources is to use Near Field Lenses (NFLs). NFLs are collimators using refraction and total internal reflection (TIR) to efficiently collect and direct light. They tend to have thick sections and therefore require challenging molding techniques, and they may have the LED source optically coupled directly into them. Beside these functional aspects, NFLs offer unique styling for different lighting functions such as those in rear combination lamps (RCLs), front turn signal lamps, daytime running lamps (DRLs) and headlamps.

During last 10-15 years we could have seen quite big changes in automotive lighting. The most important changes are: a) plastic materials mostly removed metal and glass material from lighting products raised heat issue of plastics materials b) escalation of competition between lighting suppliers (globalization, merging, …) decrease of time and cost for development of the new product as much as possible

A practical and low cost Blind Spot Monitoring system is proposed. By using a single camera, the range and azimuth position of a vehicle in a blind spot are measured. The algorithm is based on the proposed RWA (Range Window Algorithm). The camera is installed on the door mirror and monitoring the side and rear of the host vehicle. The algorithm processes the image and identifies range and azimuth angle of the vehicle in the adjacent lane. This algorithm is applied to real situations. The 388 images including several kinds of vehicles are analyzed. The detection rate is 86% and the range accuracy is 1.6[m]. The maximum detection range is about 30[m].

As global automobile manufacturers prepare for the phase-out of R134a in Europe, they must address the issue of using the new refrigerant for European sales only or launching the product worldwide. Several factors play into this decision, including cost, service, risk, customer satisfaction, capacity, efficiency, etc. This research effort addresses the minimal vehicle-level hardware differences necessary to provide a European solution of R1234yf while continuing to install R134a into vehicles for the rest of the world. It is anticipated that the same compressor, lubricant and condenser; most fluid transport lines; and in most cases the evaporator can be common between the two systems.

This paper presents the results of a human factors flight test evaluation of a display of Enhanced Traffic Situational Awareness on the Airport Surface with Indications and Alerts (SURF IA). The study is an element of the FAA-sponsored Surface Conflict Detection and Alerting with Consideration of Arrival Applications program. The objective of the flight test was to conduct a comparative evaluation of two candidate SURF IA displays: a detailed Airport Surface Situation Awareness (ASSA) display and a runways-only Final Approach Runway Occupancy Awareness (FAROA) display. Six pilots with a current Air Transport Pilot Certificate each completed 18 scenarios. A Beechcraft King Air C-90 and a Cessna Citation Sovereign aircraft were deployed for the flight tests. The scenarios were conducted at Seattle-Tacoma International Airport and at Snohomish County Paine Field Airport, with each aircraft acting as ‘traffic’ for the other aircraft.

This paper presents new concepts for improving management of the electrical load power regeneration of an aircraft. A novel electrical system that allows for load regeneration back to the distribution bus is described. This approach offers the benefits of reduced weight, volume, and cost, as well as improved reliability. Also described is an electrical machine control mechanism that creates motor power to run the prime mover (i.e., the main engine to dissipate the regenerated power). Instead of main engine generation, this approach can be applied to an auxiliary power unit (APU) or power and thermal management system (PTMS). Background information regarding the regeneration concept is presented. The concept definition and the various modes of operation of the improved system are analyzed and described in detail. Results from the dynamic simulation of the system model are included.

In Brazil the market for plastic parts molds, in last few years had become very competitive, with several Vehicle Operations and a big number of a different models, and with today total market volume it means low volumes productions for each model. This market demands for good toolshops and at the same time a big pressure to reduce investments, one of the most important. Plastic components usage in the car, is increasing overtime, with new applications for Exterior, interior and powertrain, requiring new technologies for Injection molding processing and making molds to be more complex. The development of plastic parts in Brazil has its own characteristics, strengths and weaknesses. In fact a big and heterogeneous market. This paper intends to present an analysis of development of plastic parts in Brazil, considering the development of mold tooling locally, focusing the automotive market.

This paper presents an unambiguous and intuitive method for identification of steering column resonant (SCR) mode of vibration. One simple but overlooked technique to determine the SCR mode in-vehicle is to provide local stiffnesses of the body locations where the Instrument Panel (IP) attaches, to the IP suppliers to be used in their design and development. This paper describes how this technique is useful in predicting the first few important in-vehicle steering column modes for different classes of vehicles, with examples presented in each class. The results obtained from such analyses are compared against those from direct in-buck simulations. This technique is not limited to its application in developing IP systems, but can easily be extended to include other systems such as seats, fuel tanks, etc. Also it is shown that a design optimization analysis may be performed using these attachment stiffnesses as design variables resulting in a system level solution.

Flow noise from automotive HVAC (Heating, Ventilating and Air Conditioning) systems is one of the major considerations of occupant comfort. The noise generated at high blower speed is a major contributor to the vehicle interior noise. This paper reviews automotive HVAC air rush noise prediction models for estimating register, buck (air handling subsystem) and vehicle noise levels. The vehicle noise prediction method correlates well with measured noise levels at driver right ear location: with a standard deviation of 1.31 dB where standard deviation is the difference between measured and predicted noise levels for a sample size of 10 vehicles.

Automotive gear oil development has expanded beyond the historical requirements of emphasizing wear protection to encompass modern needs for fuel economy and limited slip frictional properties. This paper describes the development process of a new generation, fuel efficient gear lubricant for use in light duty vehicles. A systematic formulation approach was used, encompassing fluid viscometrics and additive optimization. Performance testing in both laboratory and vehicle tests is described. Though standard GL-5 tests were used to confirm oxidation, wear and corrosion performance, emphasis is given to those methods used for optimizing fuel economy.

Stabilizer bars in a suspension system are supported with bushings by a frame structure. To prevent the axial movement of the stabilizer bar within the bushing, several new stabilizer bar-bushing systems have been developed. The new systems introduce permanent compressive force between the bar and the bushing thereby preventing the relative movement of the bar within the bushing. This mechanical bond between the bar and the bushing can eliminate features such as grippy flats, collars etc. In addition, by controlling the compression parameters, the properties of the bushing such as bushing rates can be tuned and hence can be used to improve the ride and handling performance of the vehicle. In this paper, nonlinear CAE tools are used to evaluate one such compressively loaded bushing system. Computational difficulties associated with modeling such a system are discussed.

Interior compartment doors are required by Federal Motor Vehicle Safety Standard (FMVSS) 201, to stay closed during physical head impact testing, and when subjected to specific inertia loads. This paper defines interior compartment doors, and shows examples of several different latches designed to keep these doors closed. It also explores the details of the requirements that interior compartment doors and their latches must meet, including differing requirements from automobile manufacturers. It then shows the conventional static method a supplier uses to analyze a latch and door system. And, since static calculations can't always capture the complexities of a dynamic event, this paper also presents a case study of one particular latch and door system showing a way to simulate the forces experienced by a latch. The dynamic simulation is done using Finite Element Analysis and instrumentation of actual hardware in physical tests.

Past and current practice in this industry for measuring individual loudspeaker drive units has included great freedom in choice of chamber type and baffling. Many of these methods do not yield the true acoustical response of the loudspeaker free from acoustical artifacts. In fact, international loudspeaker measurement standards and many carmaker specifications allow test set-ups that significantly mask the true response of the loudspeaker. This paper is intended to drive awareness of this issue in the industry in an effort to promote a new standard for measurement.

The purpose of this study is to develop specifically a correlation between Exhaust Manifold Cracking Laboratory Test results and 150,000 mile customer fleet usage test results. The study shows that the exhaust manifold design meets the reliability requirements of 10 years or 150,000 miles, given 90th percentile customer usage without an evidence of cracking or audible leaks. This correlation between the Lab Test and the customer Fleet results has been expressed as an acceleration factor. An acceleration factor is the ratio of how much quicker the engine dynamometer test ( i.e. Lab Test ) can accumulate the effect of customer usage over time versus the customers themselves. The acceleration factor is provided for useful life time period of 10 years or 150,000 miles. The recommended acceleration factor, determined in this study, is 38 to 1, comparing the engine dynamometer test ( i.e. Lab Test ) results to 150,000 mile modular truck customer fleet field results.

Recycled resins can meet performance requirements on products which were initially designed for virgin materials. Olefinic instrument panel (I/P) scrap is being recycled from the Mazda Tribute and the Ford Escape into glove box bins. As a result, a quality part is being supplied to the customer and Visteon's Saline Plant has realized both increased plant operating efficiencies and landfill cost avoidance. The development process is described including: plant regrind sources, part molding and testing.

Previously we reported to the SAE 2000 basics in selection of various colored and un-colored/natural nylon 6 (polyamide - PA 6) based plastics for laser welding technology. Later we presented to Antec1 2001 and to SAE 2002 our developments of colored in black through-transmissible grades of PA 6 plastics, which were specially tailored for the specifics of the design and laser welding technology. In this current paper, we will try to enhance the understanding of the engineering community regarding the usefulness and applicability of laser welding technology, developed colored thermoplastics, and its increasing use in various automotive and transportation applications.

Previously we reported to SAE 2002 the basic principles in materials selections for the fastening of plastics. In this current paper, we will try to increase the understanding of the automotive community regarding the usefulness and applicability of aluminum made self-tapping screws in the fastening of various thermoplastic components. Utilization of the light alloys for the manufacturing of fasteners for plastic applications allowed us to manage efficiently the stiffness considerations, short- and long-term performance of the assembled plastic components. The results presented in this study will help designers, technologists, thermoplastic and fastener developers and fastener manufacturers, to optimize mechanical performance of assembled automotive components, where self-tapping screws will be used.