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The two major transportation industries of America, automobile manufacturing and highway building, have coexisted for a century. Now, more is being asked of this partnership. A growing population that desires a growing economy is confidently predicting the need to make more trips but is not satisfied with the vision of building more roads and highways on which to make them, nor are they satisfied with their safety while on the road. The challenge is improve safety and use more efficiently what we have already built: Hence the USDOT's strategy: to apply automation technology advances to both the vehicles and the highway - and, most importantly, to integrate the two into a vehicle-highway system. Further, to bring about this merger of industries within a framework specifically designed to invite and utilize the participation of all stakeholders interested in this national investment.

A cast skin instrument panel has been developed that passes a heat age test of 21 days at 121 degrees centigrade, 1993 kJ/m Xenon Arc exposure and 200,000 Langleys of Arizona exposure. The instrument panel showed acceptable color change and no cracking or shrinkage of the skin was seen after the Arizona aging. This panel was developed by careful selection of the vinyl compound and polyurethane foam and no topcoats were used on the PVC skin to control color or gloss.

A unique approach to intercity highway transportation entitled PAC-ITS: Packet Autopiloted Cruiseway - Intelligent Transportation System, has been detailed in a recently completed contract for the National Automated Highway System Consortium (NAHSC). The PAC-ITS concept focuses on: (1) improving the productivity of intercity travel (2) facilitating increased highway speeds in a safe and environmentally permissible manner; and (3) minimizing automation complexities. Key concept features include: Use of PAC-ITS convoys which are composed of a mix of 15 or 20 vehicles - personal cars, buses and freight units - electronically and mechanically linked together. Interconnection of all vehicle power trains and brakes enabling unified convoy acceleration and braking. Individual active lateral guidance for each convoy vehicle Professional “pilot” control of each convoy from a specially equipped lead vehicle.

This paper describes a joint development and testing program between Tier I suppliers and a North American automotive company to determine the efficacy of a new generation of cure-in-place gasketing materials (CIPG) as flange seals for water pumps. Employing a systems approach to validate design and process test procedures, the program demonstrated that this chemically-based material provides superior performance in applications requiring resistance to powertrain fluids. When combined with proper flange design, process controls, and dispensing systems, it proved robust and economical. Compared to the sealing methods and material it replaced, the new CIPG compound delivers improved processing, manufacturing flexibility, and enhanced quality.

AVCS applications for productivity enhancement can be implemented now to produce a positive return on investment, unlike systems developed for the consumer automobile market which will not be commercially available in the near term. This area of development has been previously neglected because commercial vehicle and transit operators have been unaware of the maturity of AVCS technologies. AVCS researchers have focused almost exclusively on safety applications. It is widely believed that barriers to many AVCS applications are more due to institutional, economic, and legal issues than technology limitations. In order to sustain and accelerate the AVCS deployment process, it is desirable to demonstrate the benefits of AVCS in the very near future.

The rear crankcase is a challenging application for radial lip seals. High repair costs make it desirable to seal this area over the life of the engine. One step towards this goal is the combination of sealing system components into one module. Limitations of the elastomeric sealing lip lead to the incorporation of PTFE elements. The recent development of a thermoplastic flange material meeting the high requirements for thermal, chemical and mechanical stability results in weight and cost reduction with a high degree of sealing reliability.

Conventional practice is for automotive engine lubrication filter designers to include many devices in a typical “spin-on” filter. These include the filter element housing, tapping plate, and internal components, such as, an anti-drainback valve, the filter element structural support, the filter media and in some cases, the safety relief valve. Understanding the interaction of all these components before a prototype is built greatly aids in achieving a functional, cost effective solution to meet required flow and pressure drop, filtration efficiency, and contaminant capacity requirements for a particular filter. Furthermore, the investment in modeling a specific filter design enables variations or modifications to be made to the original design very easily and at little cost. This paper presents a detailed mathematical flow model that was developed for a new type of dual flow filter.

System contamination caused by contaminates or small particles built-in, self-generated, or inhaled from environment presents severe problems. The problems include but are not limited to the malfunctioning of valves, pumps, seals and injectors or lock-up of these components; increased wear of bearings, piston rings, and other friction components; and degradated machine performance. In general, system contamination changes a deterministic system into a stochastic system and shortens machinery service life. In this paper, these contamination problems are discussed in categories and associated analysis, testing and computer modeling methodologies are also discussed.

Heavy duty engine and driveline radial lip seals have numerous applications where severe environmental conditions are known to exist. The most severe conditions are associated with construction, mining, agricultural, military and industrial applications. Under these severe conditions, traditional elastomeric and PTFE dust lips are not capable of providing adequate protection for the oil seal. A new heavy duty excluder sealing system for radial lip seals has been designed and developed as a solution to premature failure due to extreme environmental contamination. Laboratory test equipment, test procedures, and comparative test results, including bench tests and field evaluation are presented as well as some of the design variations required due to various installation schemes.

Effects of spray characteristics for stratified combustion of direct injection gasoline engine have been researched. The highly functional piezoelectric (PZT) injector was selected for this research. A hole and swirl nozzle were examined in a wide range of fuel pressure. The hole nozzle aims to make stratified mixture formation by vaporizing fuel on the piston, and the swirl nozzle aims to do so in the air above the piston by utilizing the spray characteristic of lower penetration and higher dispersibility. Both sprays could realize stable stratified combustion. The stability mainly depends on the combination of spray characteristic and piston cavity shape, and the swirl air motion which strength changes corresponding to engine operating conditions. The hole nozzle requires high, and the swirl nozzle less fuel pressure. Even by a large amount of EGR, stratified combustion has the advantage of combustion stability, and is useful to reduce exhaust emissions, especially NOx emissions.

The reliability, efficiency and ecological parameters of diesels are mainly determined by their operational perfomance in unstable conditions when the air supply to cylinders lags as compared to the fuel supply. Hereat, the excess air coefficient decreases, which results in decreasing the fuel consumption efficiency as well as the exhaust gas smoke. The aforesaidnecessitates the adjustment of the fuel feed depending upon the amount of the air supplied into cylinders. The modelling of the diesel controller system for the rotation frequency regarding the adjustment of the fuel feed depending upon the supercharging pressure is considered. The mathematical model of the diesel is based on calculating the gas - dynamic processes in each cycle of the cylinder operation, which makes it possibleto take into account the nonlinear characteristics of the diesel in different operational conditions as well as the discreteness of the fuel injection.

The refinement of heat release analysis stems from the recognition that a combustion system is intrinsically non-linear. Thus, as appropriate for such an entity, its properties are expressed in terms of a thermochemical phase (or state) space, of which the thermodynamic aspects are exposed on a so-called Le Chatelier diagram, providing the fundamental background for the development of micro-electronic control to attain the most effective utilization of fuel. Implementation of this method of approach is illustrated by the analysis of the exothermic process taking place in two typical internal combustion engines, spark-ignition and diesel.

This paper describes an experimental investigation to explore and optimise the performance, economy and emissions of a direct injection gasoline engine. Building on previous experimental direct injection investigations at Ricardo, a single cylinder engine has been designed to accommodate common rail electronically controlled fuel injection equipment together with appropriate port configuration and combustion chamber geometry. Experimental data is presented on the effects of chamber geometry, charge motion and fuel injection characteristics on octane requirement, lean limit, fuel consumption and exhaust emissions at typical automotive engine operating conditions. The configuration is shown to achieve stable combustion at air/fuel ratios in excess of 50:1 enabling unthrottled operation over a wide operating range. Strategies are demonstrated to control engine out emissions to levels approaching conventional port injected gasoline engines.

Driveline control is a challenging area. With traditional fuel metering systems, driveline oscillations may follow load disturbances or changes in accelerator position. This problem, emphasized with increased engine power, together with overall increased performance demands leads to a need for more advanced driveline control. The main contribution of the paper is a strategy for fuel metering with active handling of driveline resonances, reducing wheel speed oscillations. Experiments and modeling using a 6x2 heavy truck lead to a linear model capturing the significant torsional resonances in the driveline. A formulation tractable for analysis, design, and implementation is developed. Field trials show that the engine can be controlled to reduce low frequency driveline oscillations, also when facing engine torque restrictions due to diesel smoke reduction. The system thus improves both performance and driveability.

Meeting future exhaust emission and fuel consumption standards tor passenger cars will require refinements in how the combustion process is carried out in spark ignition engines. A direct injection system decrease fuel consumption under road load cruising conditions, and stratified charge of the fuel mixture is particularly effective for ultra lean combustion. To achieve stable combustion at an ultra lean air fuel ratio, fuel spray speed, angle, droplet diameter and in-cylinder air behavior must be optimized. In this paper, the engine system which has an injector and spark plug located in the center of combustion chamber, and has a flat type piston was investigated. We adopted a swirl type injector (fuel pressure 5MPa) which gave a droplet diameter of 20 μ m. Swirl air motion was applied in the cylinder to concentrate the fuel mixture at its cylinder center. Fuel spray speed was decreased to under 30m/s to keep the mixture at the top of the cylinder.

A new 2.0 ℓ DOHC 4-valve direct injection (DI) gasoline engine has been developed which features new technologies such as swirl intake ports to produce an optimum swirl in the cylinder by variable controlled swirl control valve, pistons with a concave combustion chamber, and high pressure fuel injection system to provide a fine fuel-air mixture cloud in the combustion chamber. These all help to control fuel-air mixture preparation and flame propagation under ultra lean, stratified combustion at partial loads. NOx emission is reduced by using an electrically controlled EGR system and an NOx storage-reduction catalyst. At higher loads, a homogeneous mixture is obtained with direct injection during the intake stroke. A seamless output torque transition between stratified charge and homogeneous charge condition is achieved by an electronic throttle control system.

This paper discusses the development of a 1994 Ford Taurus vehicle model for the National Advanced Driving Simulator's planned vehicle dynamics simulation, NADSdyna. The front and rear suspensions of the Taurus are modeled using recursive rigid body dynamics formulations. To complement vehicle dynamics, subsystems models that include steering, braking, and tire forces are included. These models provide state-of-the-art high fidelity vehicle handling dynamics for real-time simulation. The realism of a particular formulation depend heavily on how the parameters are obtained from the physical system. Therefore, the development of a data set for a particular model is as important as the model itself. The methodology for generating the Taurus data set is presented. The power train model is not yet included, so the simulation is run with the vehicle either at constant speed or decelerating.

The major problems of the various mixture formation concepts for direct injection gasoline engines that have been proposed up to the present were caused by the difficulties of preparing the mixture with adequate strength at spark plug in wide range of engine operating conditions. Novel combustion control technologies proposed by Mitsubishi is one of the solution for these problems. By adopting upright straight intake ports to generate air tumble, an electromagnetic swirl injector to realize optimized spray dispersion and atomization and a compact piston cavity to maintain charge stratification, it has become possible to achieve super-lean stratified combustion for higher thermal efficiency under partial loads as well as homogeneous combustion to realize higher performance at full loads. GDI™ (Gasoline Direct Injection) engine adopting these technologies is developed. At partial loads, fuel economy improvement exceeding 30 % is realized.

This paper presents an evaluation of a vehicle dynamics model intended to be used for the National Advanced Driving Simulator (NADS). Dynamic validation for high performance simulation is not merely a comparison between experimental and simulation plots. It involves strong insight of vehicle's subsystems mechanics, limitations of the mathematical formulations, and experimental predictions. Lateral, longitudinal, and ride dynamics are evaluated using field test data, and analytical diagnostics. The evaluation includes linear and non-linear range of vehicle dynamics response.

As part of the National Advanced Driving Simulator (NADS) program, the Vehicle Research and Test Center (VRTC) in East Liberty, Ohio is evaluating the NADS vehicle dynamics software. As part of VRTC's effort, an extensive vehicle testing program to provide data for the simulation evaluation was performed. This paper describes VRTC's testing of a 1994 Ford Taurus GL passenger car. Each of the test maneuvers run by the Taurus are described, along with instrumentation setup, control actuation, test conditions, and driver procedures. The test data reduction and processing are detailed. Sample results of the testing and an analysis of test repeatability and measurement noise are also presented.