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Diesel engine control has already become complex, and in order to meet future emissions standards (such as Euro 4) it is likely to be the control system that will provide the needed performance increment. Common rail fuel injection offers yet more degrees of freedom which will need to be exploited as new emissions standards emerge. Whatever the emissions standards, there is a need to reduce risk at the earliest stages in the development of the powertrain. This will involve early and extensive simulation of the powertrain including its control system, sensors and actuators. What is the best way to achieve this using current tools? The result lies in a combination of a phenomenological model of the engine and a flexible controls environment. To illustrate the principles of developing prototype control systems, we will use the example of the CPower environment, which is a combination of a detailed engine simulation code (GT-Power) and the Simulink simulation environment.

Electronic throttle control is increasingly being considered as a viable alternative to conventional air management systems in modern spark-ignition engines. In such a scheme, driver throttle commands are interpreted by the powertrain control module together with many other inputs; rather than directly commanding throttle position, the driver is now simply requesting torque - a request that needs to be appropriately interpreted by the control module. Engine management under these conditions will require optimal control of the engine torque required by the various vehicle subsystems, ranging from HVAC, to electrical and hydraulic accessories, to the vehicle itself. In this context, the real-time estimation of engine and load torque can play a very important role, especially if this estimation can be performed using the same signals already available to the powertrain control module.

In this paper, the prototypes of electric cars done by the Engineering & Infrastructure Transportation Area in the Department of Mechanical Engineering of the University of Zaragoza is presented. The project started in 1993, the initial stage started doing calculation and construction of prototype I which was used as a technological demonstrator. The prototype I, was a very simplified electric vehicle with particular performance qualities. Prototype II has the features of an urban car comparable to the current combustion cars for urban purposes. A program of testing will be done in order to find problems that can be corrected for the prototype III, in which all the parameters analyzed will be corrected for a serial manufacture.

This paper describes SHEV, a computer program created to simulate hybrid electric vehicles. SHEV employs the time-stepping technique in order to evaluate energy flow in series hybrids, and makes use of a unique method in order to speed up the fuel economy estimation. This estimation method is a refinement of the “state of charge matching” method and is explained in detail. The graphic user interfaces employed in SHEV make it easy to use and give it a look similar to regular Windows‚ applications. This paper also gives some examples of the screens created by the program, depicts its main flowchart, and describes a battery model optimized for this application.

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.