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Accurate evaluation of vehicles' transient total power requirement helps achieving further improvements in vehicle fuel efficiency. When operated, the air-conditioning (A/C) system is the largest auxiliary load on a vehicle, therefore accurate evaluation of the load it places on the vehicle's engine and/or energy storage system is especially important. Vehicle simulation models, such as "Autonomie," have been used by OEMs to evaluate vehicles' energy performance. However, the load from the A/C system on the engine or on the energy storage system has not always been modeled in sufficient detail. A transient A/C simulation tool incorporated into vehicle simulation models would also provide a tool for developing more efficient A/C systems through a thorough consideration of the transient A/C system performance. The dynamic system simulation software MATLAB/Simulink® is frequently used by vehicle controls engineers to develop new and more efficient vehicle energy system controls.

The paper addresses compressor body temperature (crankcase) importance to the vehicle AC system long-term durability. Majority of OEM vehicle test evaluation is to see if AC system can pass compressor discharge temperature and discharge pressure targets. Most OEMs adopt 130°C max compressor discharge temperature and 2350 kpag head pressure as the target. From the field, although some of the compressor failure results from a high compression ratio, and compressor discharge temperature that are caused by the poor front end airflow, etc., high percentage compressor failed systems exhibit not too high compression ratio and compressor discharge temperature, but having the trace of high temperature in the shaft area, gasket area, etc. With introducing more and more variable swash plate compressor applications, OEMs start to see more and more compressor failures that are not related to a high compressor discharge temperature but the trace of high compressor body temperature.

Estimation and prediction of residual life and reliability are serious concerns in life cycle management for aging structures. Laboratory testing replicating fatigue loading for a typical military aircraft wing skin was undertaken. Specimens were tested until their fatigue life expended reached 100% of the component fatigue life. Then, scanning electron microscopy was used to quantify the size and location of fatigue cracks within the high stress regions of simulated fastener holes. Distributions for crack size, nearest neighbor distances, and spatial location were characterized statistically in order to estimate residual life and to provide input for life cycle management. Insights into crack initiation and growth are also provided.

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.

SAE ARP 4260 Photometric and Colorimetric Measurement Procedures for Airborne Electronic Flat Panel Displays [1] has recently been revised. This new revision reaffirms that ARP 4260 is pertinent to the aviation industry, changes the content to keep up with the state of the art, and adds clarification where needed. ARP 4260 contains methods used to measure the optical performance of airborne electronic flat panel display systems and is referenced in SAE ARP 4256, Design Objectives for Liquid Crystal Displays for Part 25 (Transport) Aircraft [2] and in SAE AS 8034, Minimum Performance Standard for Airborne Multipurpose Electronic Displays [3].

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].

This paper discusses the problem of obtaining electric machines (EM) for advanced electric drives (AED) used in more electric architecture (MEA) applicable to aircraft, spacecraft, and military ground vehicles. The AED are analyzed by those aspects of Six Sigma theory that relate to critical-to-quality (CTQ) subjects. Using this approach, weight, volume, reliability, efficiency, and cost CTQ are addressed to develop a balance among them, resulting in an optimized system. The influence of machine controllers and system considerations is discussed. As a part of the machine evaluation process, speeds, bearings, complexities, rotor mechanical and thermal limitations, torque pulsations, currents, and power densities are considered. A methodology for electric machine selection is demonstrated. An example of high-speed, high-performance machine application is shown. A system approach is used for overall electric machine selection and optimization.

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

High-power LEDs and LED headlamps have become a serious consideration for the automotive industry. White LEDs have achieved the required performance for initial automotive headlamp applications. However tradeoffs among several attributes such as efficiency, cost, weight and performance profoundly affect LED headlamp development and need to be addressed by vehicle manufacturers, lamp set makers and LED source suppliers in order for LED headlamps to be effective. The solutions to these tradeoffs relates to the behavior of the LED sources, the thermo-mechanical integration of LEDs in a headlamp environment and input from the vehicle manufacturer regarding styling and packaging for an LED headlamp on the respective targeted vehicles.

Recent advances in the state of the art of space-borne data processors and signal processors have occurred that present some unprecedented constraints relating to their power needs. Such processors include the class of multiprocessors providing computational capabilities in the billions of floating point operations per second. Processors of this type tend to require use of modern radiation tolerant or radiation hardened integrated circuits requiring very low voltage power supplies that place considerable challenge on power distribution and conversion within those processing payloads. The primary challenges are efficient conversion of power from the spacecraft power bus to these low voltages and distribution of the very high accompanying currents within the payload while maintaining proper voltage regulation (typically +/− 5%). Some integrated circuits require 10 Amps or more at 1Volt, as an example [3], [6].

Up to date, computer aided engineering (CAE) has been used in improvement of design quality and reduction of cost and delivery time. Although it has been widely accepted as a standard product development tool by the engineering community, CAE still faces many challenges in improving simulation process efficiency through process integration and automation, and simulation accuracy by analytical model/physical testing correlation. CAE engineers are constantly improving the accuracy of their analytical models through test correlation to deliver higher confidence for their analysis result. Although laboratory testing has provided an effective way to accelerate product development, analytical simulation of the lab test has been used frequently to further reduce the development cost and time throughout many industries. This paper presents a case study of CAE correlation of a finite element (FE) model of an automotive beam axle assembly in a laboratory test environment.

Computational Fluid Dynamics (CFD) is an integral part of product development at Visteon Climate Systems with a validated set of CFD tools for airflow and thermal management processes. As we increasingly build CAE capabilities to design not only thermal comfort, but quiet systems, developing noise prediction capabilities becomes a high priority. Two Broadband Noise Source (BNS) models will be presented, namely Proudman's model for quadrupole source and Curle's boundary layer model for dipole source. Both models are derived from Lighthill's acoustic analogy which is based on the Navier-Stokes equations. BNS models provide aeroacoustic tools that are effective in screening air handling systems with higher noise levels and identifying components or surfaces that generate most of the noise, hence providing opportunities for early design changes. In this paper, BNS models were used as aeroacoustic design tools to redesign an automotive HVAC center duct with high levels of NVH.

Steer-by-wire systems (SBW) offer the potential to enhance steering functionality by enabling features such as automatic lane keeping, park assist, variable steer ratio, and advanced vehicle dynamics control. The lack of a steering intermediate shaft significantly enhances vehicle architectural flexibility. These potential benefits led GM to include steer-by-wire technology in its next generation fuel cell demonstration vehicle, called “Sequel.” The Sequel's steer-by-wire system consists of front and rear electromechanical actuators, a torque feedback emulator for the steering wheel, and a distributed electronic control system. Redundancy of sensors, actuators, controllers, and power allows the system to be fault-tolerant. Control is provided by multiple ECU's that are linked by a fault-tolerant communication system called FlexRay. In this paper, we describe the objectives for fault tolerance and performance that were established for the Sequel.

An algorithm, which determines the range of a preceding vehicle by a single image, had been proposed. It uses a “Range-Window Algorithm”. Here in order to realize higher robustness and stability, the pattern matching is incorporated into the algorithm. A single camera system using this algorithm has an advantage over the high cost of stereo cameras, millimeter wave radar and non-robust mechanical scanning in some laser radars. And it also provides lateral position of the vehicle. The algorithm uses several portions of a captured image, namely windows. Each window is corresponding to a predetermined range and has the fixed physical width and height. In each window, the size and position of objects in the image are estimated through the ratio between the widths of the objects and the window, and a score is given to each object. The object having the highest score is determined as the best object. The range of the window corresponding to the best object becomes an estimated range.

Virtual design validation of an air induction system (AIS) requires a proper finite element (FE) assembly model for various simulation based design tasks. The effect of the urethane air filter seal within an AIS assembly, however, still poses a technical challenge to the modeling of structural dynamic behaviors of the AIS product. In this paper, a filter seal model and its modeling approach for AIS assemblies are introduced, by utilizing the feature finite elements and empiric test data. A bushing element is used to model the unique nonlinear stiffness and damping properties of the urethane seal, as a function of seal orientation, preloading, temperature and excitation frequency, which are quantified based on the test data and empiric formula. Point mobility is used to character dynamic behaviors of an AIS structure under given loadings, as a transfer function in frequency domain.

Tuned mass dampers are frequently used in vehicles to resolve vibration issues arising from problematic torsional modes. The design of a tuned damper is straightforward, but evaluating its effect on other system modes is time consuming. An upfront design tool will accelerate the process of designing and evaluating the damper's affect on system level dynamic characteristics. Computer aided engineering tools have been developed to design a tuned torsional damper using two different approaches. In the first approach, a two-degree of freedom torsional system model is utilized. In the second approach, a detailed finite element model of a driveline system is considered. In the second approach, the effect of the damper to the vehicle driveline system response at the hypoid pinion nose and other desired locations is studied to assess the effectiveness of the damper design. In both approaches, the damper rotational inertia is considered as a design variable.

Determination of the critical speed of a driveshaft is critical for development and validation of its design for use in a vehicle because of its destructive effects. Typical calculations to determine critical speed are either over simplistic and not very accurate or very complicated requiring CAE software and capabilities. An analytical five-section non-prismatic beam model was developed to fill in this gap. The model was developed to compute the critical speed in a worksheet and proven to be as or more accurate as utilizing FEA methods. The model worksheet calculates the critical speed for one-piece conventional driveshafts and adapted for Visteon's Slip-In-Tube (SIT) driveshafts.