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The British Columbia vehicle emissions inspection and maintenance, I/M, program, AirCare, has monitored the performance of technicians and repair centres since program inception. The purpose of performance monitoring is to oversee the effectiveness of technicians who are certified to perform emissions related repairs after a vehicle has failed the initial I/M inspection. Since June, 1995, the Program Administration Office, PAO, has been working on refining the parameters used to assess repair effectiveness. This paper describes the development and implementation of Repair Effectiveness Indices to monitor the effectiveness of repairs performed by the certified automotive repair industry with respect to the AirCare Program. Repair Effectiveness Indices, REIs, apply to certified repair technicians and repair centres and are provided to the technicians and repair centres on a regular basis.

This paper proposes a new approach for vehicle location for Intelligent Transportation Systems, the Visual Protocol System (VPS). VPS has three key system components a protocol for the presentation and interpretation of information within a visual scene, standards for roadway labels, and an in-vehicle system composed of hardware and software to implement the visual protocol and feed information to an in-vehicle navigation system. This concept has an advantage of low cost when compared with active roadside beacons, and a very great advantage of multiple use potential and expandability when compared with single-use GPS technology.

A method for assessing the annual mileage of a fleet of vehicles has been developed, which depends on tracking individual vehicles from year to year. Although significant data manipulations are required, the method is more reliable than previous sampling methods, and it has shown that these sampling methods actually underestimate annual mileage. The method has been used to show that annual mileage is related to model year, engine size, net weight, and historical mileage; and that vehicles which pass emissions inspection tend to have slightly lower mileages; but there is very wide variation about the mean. The most significant factor in determining the total annual mileage for a particular vehicle group is simply the number of vehicles in that group.

A Kenworth T800 heavy duty dump truck operating on compressed natural gas has been in service with the city of Surrey, British Columbia. The truck uses a Cummins L-10-300G engine, a dedicated spark ignition engine. Fuel is stored in Dynetek high capacity cylinders, and a data logging system is fitted to monitor performance and fuel consumption of the truck. The truck is used in municipal service moving gravel and asphalt to work sites. A typical day's use is about 200 km. The truck has been modified significantly throughout the project. A stoichiometric natural gas engine has been replaced with a lean burn engine and the fuel capacity has been increased. One of the key findings in the demonstration has been that fueling stations must have their storage sized to the fuel capacity of the largest vehicle in order to allow reasonable refueling times.

A new injector has been designed for sequential injection of high-pressure natural gas and a quantity of liquid diesel fuel directly into diesel engine cylinders late in the compression stroke. Injected a few degrees before the natural gas, the pilot liquid fuel auto-ignites and serves, as it burns, to ignite the gaseous fuel which enters the chamber as an underexpanded sonic jet generating high local turbulence. Tests on a single-cylinder two-stroke engine with full electronic control have demonstrated the capability of this fueling method to nearly match conventional diesel engine efficiency over a wide range of load and substantially reduce the emissions of oxides of nitrogen (NOx), particulate mater (PM) and carbon dioxide (CO2).

In this paper a study of the squish-generated charge motion in the combustion chamber of a natural gas engine is reported. A combination of both numerical simulations and actual engine tests was used to correlate the turbulence level at the spark plug location with performance and cylinder pressure data for three different chamber configurations. The higher-turbulence combustion chamber showed an average 1.5% reduction in brake specific fuel consumption in comparison with the lower turbulence level combustion chambers. The emission levels from the high-turbulence case were, however, generally higher than those from the lower-turbulence combustion chambers.

Conformable tanks are being developed for alternate-fuel vehicles to address the issues of range and packaging of pressurized fuel storage systems Installation of an aluminum conformable tank on a propane-powered vehicle within the same volumetric envelope as the gasoline tank has demonstrated a range increase of over 40% compared to conventional cylindrical tanks Injection-molded plastic conformable tanks for propane and adsorbed natural gas are currently under development to increase vehicle range at reduced cost The potential for improvements in storage capacity at the higher pressures required for compressed natural gas storage has also been demonstrated through the use of advanced composite materials

Rapid bus applies rapid transit thinking to bus operation. Designed to revitalize bus services, rapid bus is targeted at corridors where conventional bus service has reached saturation, while investment in high capacity rail transit cannot be justified for financial reasons. Rapid bus uses new technology and rail based marketing to grow ridership in medium density markets.

THE PROBLEM - Due to our modern technologies and societal desires, we have created a comfortable low density lifestyle that is the envy of the world. However, the population has increased to a point where certain areas such as the major cities in the US and the world are congested with private vehicles moving from low density living areas to high density working areas using an enormous amount of ever more scarce fuel and polluting the atmosphere. People in these places loose valuable productive time in their lives. The commuting time has increased from minutes to hours. The solution used to solve congestion and poor societal conditions in the past was to use Cost Effective Mass Transportation.

This paper is the first in a series of papers describing the approach used to establish the benefit of forward collision warning systems and to identify the specific types of forward impact crashes that collision avoidance systems would be most effective in preventing or mitigating. Classes were identified for forward impact events and then the population of each crash type was determined. Further analysis was performed on the 1992 General Estimates Systems electronic database to estimate the damage or loss associated with each crash type. Velocity distributions necessary for effectiveness models were also derived from the database. Later papers will describe and present a methodology to use this classification approach in the development of a simulations program to further refine the population of events that could be prevented and/or the degree of mitigation attributable to a collision warning system.

With the development and introduction of advanced vehicle control systems such as intelligent cruise control (ICC) and forward collision avoidance systems (FCAS), many safety and human factors issues specific to these control systems are being raised. This paper addresses some issues that, to date, are still matters for discussion and consideration amongst system designers. Aimed principally at the implementation of ICC, some items naturally lend themselves to the design of forward collision avoidance systems as well. Specific issues discussed include: seat belt lock-out systems, foot placement sensing, and adjustable headway.

This paper continues the analysis of data published previously, focusing on steering wheel behavior and its correlation with driver fatigue (as measured by EEG, heart rate, and subjective evaluation of drowsiness from video). New steering-based weighting functions devised from observed changes in steering wheel motions are presented. Significant correlations between the weighting functions and the measures of driver fatigue suggest that some of the functions could form the basis of a fatigue-detection algorithm.

A variable stability test bed is under development for the National Highway Traffic Safety Administration (NHTSA). The Variable Dynamic Testbed Vehicle (VDTV) is being designed for research and testing of advanced collision warning and avoidance technologies being developed by industry and most likely being made available to consumers in the near future. The VDTV will also be used by NHTSA in support of the Automated Highway System (AHS) Program and possibly by the AHS program directly. The VDTV will have advanced dynamic subsystems that can be varied by on on-board programmable computer Suspension, steering, throttle, and braking will thus be controlled through selected algorithms that may be changed to provide a reasonably broad range of vehicle dynamic characteristics. The vehicle is inherently a drive-by-wire system, is instrumented for both vehicle and human factor measurements, and is therefore ideally suited to many Intelligent Transportation Systems (ITS) applications.

This paper presents a look-ahead driver model with potential application to autonomous cruising of vehicles on highways. The driver model has two physically meaningful parameters: the look-ahead distance and the steering sensitivity. The two parameters are scheduled with respect to the vehicle speed using a preprocessor that converts open-loop steering response data to pseudo-closed-loop steering response data. Sample simulations with a realistic three-dimensional multibody vehicle model are presented for a lane-change scenario. The results indicate that the proposed driver model performs well for a wide range of vehicle speeds.

An important basis of the technology strategy of the Partnership of a New Generation of Vehicles (PNGV), is the assumption that major advances in a number of different technologies must be made, before the realization of most of the challenging goals of the new generation of vehicles. One of those technologies is the reliance on lightweight alternative materials in order to produce lightweight components to achieve the projected fuel economy increases. However, this push toward lightweight components should not be on the basis of sacrificing vehicle performance, handling, reliability or safety. Toward this objective, engineers frequently are relying on super-fast computers as well as new approaches to achieve a new generation of designs of automotive components, based on some form of optimization techniques. These techniques however, usually imply increasing the number of constraints imposed on a particular design objective, which is the weight of the vehicle in this case.

This study evaluates a prototype, light-duty natural gas vehicle using lean-burn technology. Emissions and fuel economy for lean-burn operation are compared to that of stoichiometric operation. The vehicle is a sub-compact, 1991 Chevrolet Turbo Sprint. Multi-port natural gas injection was used to fuel the engine at a relative air/fuel ratio of 1 4. The main analysis evaluates emissions and fuel economy of lean-burn operation using California Air Resources Board specified emission-testing fuel. Comparisons are made to stoichiometric natural gas and gasoline operation. As well, engine-out versus tail-pipe emissions are presented, along with a brief analysis of emission sensitivity to fuel composition. Lean-burn results show a 33 3% improvement in fuel economy over Transport Canada's gasoline results and a 9 5% improvement over stoichiometric operation on natural gas.

The regenerated diesel engine offers the substantial performance advantages that are thermodynamically available when thermal regeneration is applied to a reciprocating internal combustion engine. This paper describes this new form of reciprocating engine and provides an update of the results of feasibility studies and development efforts now in progress. This regenerated engine R&D is being accomplished under a jointly funded, integrated effort involving the US Navy, Caterpillar Inc., the ReJen Co., NASA, and Ultramet Inc. This paper describes only the R&D efforts performed at ReJen and Ultramet.

In the past decade many in-cylinder approaches were proposed for simultaneous reduction of NOx and smoke with various degrees of success in operation. In this paper, results from a novel and promising technique referred to as Interacting-Sprays injection concept is presented. A single-cylinder compression-ignition two-stroke research engine with optically-accessible head, mounted on a high-speed CFR engine crankcase was used to investigate the combustion and emission characteristics of this injection system. The Interacting-Sprays injection system produces two separate independently-control led sprays with a good degree of adjustability with regard to their fuel quantities and injection timings. The impingement schedule of the two sprays on each other at the right time and place in the combustion chamber is the key to the success of the Interacting-Sprays system.

A new form of variable geometry, extended expansion, four-stroke internal combustion engine is described that is unable to employ squish over the full operating range. Accordingly a prediction was made of the influence of squish on the production of kinetic energy available for turbulence generation in a representative spark-ignition engine. It was found that the contribution of kinetic energy useable during the combustion process was commonly in the region of about 6% of that due to induction. It was, therefore, deduced that for typical spark-ignition engines the major benefit derived from the provision of squish surfaces is the resultant compactness of the combustion zone. Several techniques to counter the penalty resulting from the elimination of squish were reviewed. It was found that the most promising device was a turbulator incorporating low-pressure, compressed air, injection into the cylinder at the end of induction.

An electronic fuel/air mixture controller has been developed which is designed to reduce exhaust emissions on small utility engines. Lean Power Corporation has conducted a field study using this controller in cooperation with the United States Postal Service. Additional laboratory testing was performed in cooperation with the U.S. Environmental Protection Agency using the SAE J1088 test procedure. In this study, electronic air/fuel mixture controllers were installed and exhaust emissions evaluated on a sample of lawnmowers and engines. A significant reduction was achieved in Carbon Monoxide and the sum of Hydrocarbons plus Oxides of Nitrogen with the electronic mixture controller.