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One of the most widely used computer simulation tools for hybrid electric vehicles (HEVs) is the ADvanced VehIcle SimulatOR (ADVISOR) developed by the National Renewable Energy Laboratory. The capability to quickly perform parametric and sensitivity studies for specific vehicles is a unique and invaluable feature of ADVISOR. However, no simulation tool is complete without being validated against measured vehicle data to insure the reliability of its predictions. This paper details the validation of ADVISOR using data from the Virginia Tech FutureCar Challenge Lumina, a series HEV. The modeling process is discussed in detail for each of the major components of the hybrid system: transmission; electric motor and inverter; auxiliary power unit (fuel and emissions); batteries; and miscellaneous vehicle parameters. The integration of these components into the overall ADVISOR model is also described. The results of the ADVISOR simulations are then explained.

This morning/afternoon I intend to look very briefly at the nature of patents and how they can be used as an integral part of the product development process. In particular I will look at three different forms of power and power storage currently being developed. These are lithium batteries, fuel cells and hybrid Vehicles. Within this paper I have looked at these developments in electric vehicle technology by using patent abstracts from 40 different issuing authorities over a five year period. To do this I have searched on-line using Derwent's World Patent Index (DWPI), a collection of 16 million patents abstracts going back some 40 years, and have used the various statistical analysis tools that are available with the file. From this analysis I have identified which companies are the major players in the development of each of the technologies I have focused upon.

The Formula Lightning is an exciting part of GMI Engineering & Management Institute's motorsports program. This project is an excellent opportunity for students to apply and test their acquired classroom skills in practical applications. Competing in six race events annually, students are exposed to high caliber competitions in engineering design, combined with the thrill of racing. The Formula Lightning is a unique high-speed electric vehicle. Most of the challenging engineering tasks lie within the drive train design and battery system efficiency. Part of the battery system design and development includes a quick and reliable technique for exchanging battery packs under race conditions. Designed and built by GMI students, this project encompasses all fields of engineering giving experience with mechanical and electrical design as well as project management and marketing.

A foundation of battery normalizations, modeling and control techniques is presented for charge sustaining HEV applications. Charge and voltage based battery state observers and controllers are compared. The voltage based technique is shown to provide robust state control, as it directly constrains terminal voltage. Additionally, it provides good power cycle efficiency, and is insensitive to the initialization and drift problems characteristic of charge based controllers. Special attention is given to VRLA batteries, and dynamic loads from typical driving cycles. Future work is introduced which identifies battery power capability and efficiency as possible state control variables. This work was supported by a Netherland-America Foundation Fellowship, and by the staff at the Technical University of Eindhoven, the Netherlands.

Design of electric cars faces a significant growth all over the world. Powered by rechargeable batteries these vehicles can contribute significantly to the reduction of the big cities' pollution. The shape of a vehicle in our times is of major importance for the market and it represents the car's philosophy and character. Styling requires the definition of the general dimensions and layout of the car in advance. Computer aided techniques were developed to support a systematic design process of E-240, a 2400 mm long electric mini-car, developed at the University of Patras.

The U.S. Army initiated program to assess the performance potential of a semiactive advanced suspension system for its combat vehicles is addressed. This paper is a continuation of SAE paper 970386, “Semiactive Suspension: A Mobility Case Study”, Saxon, N.L. and Meldrum, W.R. Jr. This year's paper addresses actual field testing of the semiactive hydropneumatic suspension versus a standard torsion bar passive suspension on two similarly weighted Bradley Fighting Vehicles. The hardware discussed will include semiactive external in-arm hydropneumatic suspension, computer controller, and dynamic track tensioner. The relative mobility of the two systems, passive and semiactive, is evaluated through various field tests such as ride, shock, slalom, and traverse testing.

This paper presents the algorithm for a Kalman filter active vehicle suspension design. Based on simulations, two main issues have been investigated, (a) the effects of disturbances from the changes in road input and the variations of vehicle parameters on state observer estimation, (b) the benefits of adaptation of an active suspension to the changes of road input and the variations of vehicle parameters. Simulations showed the significant vehicle performance improvement from adaptation to road input; however, an adaptive Kalman filter is not very necessary.

Wheelbase preview control system that uses state and input estimator to reconstruct state and preview information is proposed. Conventional preview control systems use Kalman-Bucy filters of augmented system, which is composed of dynamics of a vehicle and a road profile for estimation scheme. Use of road model makes control performance sensitive to model errors that are inevitable in real applications. Compared with the conventional preview control systems, the proposed control system adopts a state and input estimator to estimate state and road input simultaneously. The state and input estimator does not require a road model, which makes it not robust to road model errors. However, the state and input estimator is sensitive to measurement noises, since it uses inverse dynamics of a system to estimate unknown inputs.

Renewable sources of energy need to be developed to fulfill future energy demands in areas such as the Maldives where traditional sources of raw materials are limited or non-existent. This paper explores the use of an alternative fuel derived from coconut oil that can be produced in the Maldives and can be used in place of diesel fuel. The main advantage of this particular fuel is that it is a highly saturated oil with a calorific value close to standard diesel fuel. The viscosity of the crude coconut oil is much higher than standard diesel fuel. To reduce the viscosity and to make the oil more suitable for conventional diesel engines methyl esters were produced using the transesterification process (1). The engine performed well on the coconut oil methyl esters although there was a small reduction in power consistent with the lower calorific value of the alternative fuel. Comparative performance data together with the emission levels for the two fuels are presented.

A method for recycling of mixed color automotive thermoplastic scrap into appearance automotive interior parts has been developed and shown to satisfy the following three requirements: 1) material performance 2) color appearance, and 3) economically sound. The technique developed is based on minimal separation of the colors into hues (groups of similar colors) and repigmenting to the desired color. The studies included computer formulations, laboratory verifications and plant runs. Plant runs were carried out to produce automotive interior doors (base level S-truck) with polypropylene (PP) regrind and B-pillar 325 parts with acrylonitrile-butadiene-styrene (ABS) regrind at the Delphi - Adrian plant. Two colors, ruby red and medium gray, were selected because they are the most difficult colors to match. The results of the plant runs demonstrated that color matching can be successfully achieved.

Increasingly, vehicle engineers of all backgrounds are being taxed with restrictions on time, equipment and facilities due to competitive demands for cost and lead-time reductions. This has precipitated an industry-wide interest in processes which address these restrictions and allow engineers to “do more with less.” Vehicle sound system development is just one example of a standard, necessary phase of premium vehicle design subject to continuous cutbacks. This complex, time-consuming effort spans a variety of disciplines such as transducer design, psychoacoustics and digital filters. However, the most significant contribution to the overall performance exists in the tuning of such system parameters as equalization, crossovers, gain staging, time-alignment, and other vehicle-specific audio parameters.

Defining the wireless marketing is a challenge in today's world. Companies interested in capitalizing on the wireless market for automatic vehicle location (AVL) have a number of wireless options from which to choose. One of the most exciting wireless combinations is GPS (Global Positioning System) and cellular systems. The Global Positioning System (GPS)/cellular combination can be used to create Automatic Vehicle Location systems for a wide variety of applications, from fleet management to personal security. Unfortunately, no single wireless network fits all the possible AVL applications, and choosing the best network for an application is essential to system performance. This paper reviews the current wireless technologies available in the market-place, discusses why ATX chose the wireless technology it uses, and gazes into the crystal ball to forecast the future of wireless.

Many projecting rod-type antennas, which stick to vehicles, are spoiling vehicle proportion and making wind shield noise. A flat and low-profile antenna, especially which can be conform to the vehicle body's contours. This paper proposes a new flat and low-profile antenna. The developed Band-Combining Flat (BCF) antenna is composed of multiple antenna elements, each characterized by high gain but narrow bandwidth. In order to realize TV reception, we have developed a band combining technology for the plural antenna elements. The characteristics of the BCF antenna are verified on a surface of an actual vehicle. The BCF antenna has performance for fine reception of TV broadcasting in VHF and UHF bands with high gain characteristic.

A new type of antenna, installed on the rear glass of a vehicle, to receive both Band III and L band was developed. This antenna consists of a rectangular loop, inductance elements inserted in the loop and a monopole connected to the edge of the loop. It works, through the use of the elements, both as a one-wavelength loop antenna for Band III and a half-wave dipole for L band. This antenna is (1) conformal and (2) compatible with the defogger heater grid lines. As the results of an open site test, this antenna had a higher gain than that of commercially- available whip-type multiband antennas for both bands.

A compact cassette and compact disc (CD) mechanism mounting bracket was developed for an automotive radio. The bracket, a single die cast magnesium component, offers a light weight, rigid platform for simultaneously attaching both mechanisms to create a simple modular subassembly.

The diversity effectiveness represents the signal improvement by means of an antenna diversity arrangement expressed by an equivalent fictitious number of n decorrelated antennas. With a low-cost compact 4antenna-arrangement on the backlite the diversity effectiveness is considerably higher than with a 2antenna-system with one antenna on each of the front and the back window. This is evaluated from antenna measurements and computer simulation of a Rayleigh field. Further antenna arrangements are discussed. Complex antenna systems of this kind for FM-TV-antenna diversity and AM radio require a device for selftesting of operating functions for OEM production and customer service as well.

Audio demonstration is frequently controlled by the seller. The selling methods used tend to bias the listener toward the seller's system and often mask long-term satisfaction estimates. The paper documents frequently-used selling techniques and offers suggestions for successful auditioning.

The effect of friction modifiers on the low-speed frictional properties of automatic transmission fluids (ATFs) was investigated by scanning force microscopy (SFM). A clutch lining material was covered by a droplet of test ATF, and a steel tip was scanned over the sample. The scanning speeds were varied from 0.13 to 8.56 mm /sec, and the frictional force was deduced from the torsion of the SFM cantilever. A reduction in dynamic friction due to the addition of the friction modifier was clearly observed over the entire speed range. This indicates that the boundary lubrication mechanism is dominant under this condition, and therefore surface-active friction modifiers can effectively improve the frictional characteristics. The friction reduction was more pronounced at lower sliding speeds. Thus addition of friction modifiers produced a more positive slope in the μ-ν (friction vs. sliding speed) plots, and would contribute to make wet clutch systems less susceptible to shudder vibrations.

This paper describes the relationship between the design parameters used to define the geometry of an automotive torque converter and the resultant efficiency in relation to the internal flow characteristics. Taking the turbine bias angle and the contraction ratio of the pump flow passage as specific examples, the effects of each design parameter on the internal flow characteristics and the occurrence of loss were analyzed. A three-dimensional viscous flow analysis code was used in the numerical computation procedure and a method developed independently by the authors was used in the loss analysis. The flow near the wall was visualized experimentally using a technique resembling the so-called oil film method. The visualized results showed good qualitative agreement with the numerical analysis results.

Automatic transmissions equipped with Modulated Torque Converter Clutches (MTCC) require an effective combination of automatic transmission fluid (ATF) - friction material in order to maintain frictional integrity. However, in this study, thermal analysis has shown that ATFs can interact chemically with a friction material used in the MTCC under service conditions, potentially affecting the frictional characteristics. A technique was developed to evaluate friction material degradation. The results of this study showed that the friction material my be chemically altered by static aging in certain ATFs at elevated temperatures. The statically aged friction material samples exhibited thermal analysis signatures which were similar to identical material degraded during dynamometer and fleet vehicle tests. These vehicle tests resulted in deterioration in friction characteristics and experienced shudder.