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This paper describes the evaluation methodology for the Intelligent Cruise Control (ICC) Field Operational Test (FOT). The primary purpose of the evaluation is to assess safety impacts of the ICC system. Other benefits, such as convenience and comfort, as well as impacts of the system, e.g., fuel consumption and emissions, are also being assessed. The ICC system incorporates a forward looking sensor and a headway controller with a conventional cruise control system, to automatically maintain a headway (with accelerator and downshift control inputs) between the ICC-equipped vehicle and a vehicle that precedes the equipped vehicle. The FOT will collect daily usage experiences from up to 162 lay drivers, each of whom will drive one of 10 ICC equipped vehicles for periods of 2 or 5 weeks. Data collection is scheduled to last 12 months. Each of the 10 vehicles has a data collection system that will support the evaluation.

As Intelligent Transportation Systems (ITS) become more prevalent, the need to archive data from field tests becomes more critical. These data can guide the design of future systems, provide an information conduit among the many developers of ITS, enable comparisons across locations and time, and support development of theoretical models of driver behavior. The National Highway Traffic Safety Administration (NHTSA) is interested in such an archive. While a design for an ITS data archive has not yet been developed, NHTSA has supported the enhancement of the Test Planning, Analysis, and Evaluation System (Test PAES), originally developed by Calspan SRL Corporation for the U. S. Air Force Armstrong Laboratory, for possible use in such an archive. On a single screen, Test PAES enables engineering unit data, audio, and video, as well as a vehicle animation, to be time synchronized, displayed simultaneously, and operated with a single control.

This paper will review the role of zirconium oxide in automotive systems. Zirconium oxide has been used and been considered for use in many different applications within automotive systems. Examples include ceramics for engine liners, ionic conductors for oxygen sensors, piezoelectrics for a variety of sensors and as an ingredient of autocatalysts. In the first three examples, ceramics, ionic conductors and piezoelectrics, the known properties of zirconium oxide containing systems have been applied to solve problems in the automobile. In the last the use of zirconia here has created an interest outside automotive applications. This paper will also show how a knowledge of zirconia in one field can produce benefits in another and that through this synergy improved products can be brought to the marketplace

This paper presents the methodology and initial results of an effectiveness estimation effort applied to lane change crash avoidance systems. The lane change maneuver was considered to be composed of a decision phase and an execution phase. The decision phase begins when the driver desires to perform a lane change. It continues until the driver turns the handwheel to move the vehicle laterally into the new lane or until the driver decides to postpone the lane change. During the decision phase, the driver gathers information about the road scene ahead and either present or upcoming traffic or obstacles in the destination lane. The execution phase begins when the driver starts the move into the new lane and continues until the vehicle has been laterally stabilized in the destination lane. If the driver aborts the lane change once started, the maneuver execution phase concludes when the vehicle has been laterally stabilized in the original lane.

Research in Intelligent Transportation Systems (ITS) has been increasingly focussed on the development of Collision Avoidance Systems (CAS). A CAS would reduce the incidence of collisions by providing warnings to the driver to take evasive action. Because single vehicle roadway departures, also known as Run-off-Road (ROR) events, are a cause of a significant portion of vehicle accidents and fatalities, an effective CAS for ROR can potentially improve highway safety dramatically. The development of performance specifications for CAS for ROR events is a part of an ongoing three-phase program for NHTSA (National Highway Traffic Safety Administration). This paper focusses on the development and application of a powerful simulation tool, RORSIM, for CAS assessments over a wide range of environmental, roadway, driver, vehicle and CAS operating conditions. The results of CAS effectiveness studies are presented.

This document presents preliminary guidelines for a forward looking collision warning system. The intent of a forward looking collision warning system is to eliminate or mitigate vehicular rear-end collisions through driver notification or warning. All aspects of performance are addressed including general system requirements, driver / vehicle interface methodology, collision dynamics, standardized testing and estimation of associated benefits. This guideline is intended to be used by manufacturers and developers of vehicular based forward looking collision warning systems as a tool to 1) standardize system requirements; 2) standardize driver interface and control among systems developed by different manufacturers; 3) standardize testing to be used in verifying proper operation of the forward-looking collision warning systems and; 4) measure the system benefits prior to widespread deployment of such systems.

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.