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The need for expert systems in the Heavy Truck and Bus Industry is rapidly approaching a critical point in time. This time reference is the revised emission standards and requirements for heavy duty diesels. This need is related to the influx of electronically controlled engines and their companion the electronically controlled transmission as well as the present shortage of skilled mechanics. This paper discusses the conceptual approach and reasons that expert systems are well suited as a diagnostic aid for vehicular repair. This paper also discusses the implementation of a commercially available expert system for the diagnosis of class 7 and 8 vehicles. The body of this paper will be divided into four discussions. First, applicability of AI/KB programs used for vehicle diagnostics. Second, the use of expert systems to diagnose electronically controlled power modules and their related interactivities with the vehicle.

This paper will discuss how the selection and specification of a motor fuel delivery truck or tractor/trailer can effect the safety of transporting, loading and unloading fuel. During these processes, several circumstances present themselves which could lead to explosion and fire. Ignition sources and component selections which minimize the danger posed by these ignition sources will be discussed. This paper applies to all MC-306 tank trucks and trailers, aircraft refueling tracks, and mobile dispensing carts using hydrant fueling systems (See Appendix 1).

The subject of alternate fuels has been addressed for the past 20 years in an effort to solve emissions and world fuel supply concerns. A recent study of the available literature and technology to date pointed out a need for a single source of information for the fleet operator. This paper will be divided into discussions of emissions requirements, world fuel supplies, alternate fuel options and the technical concerns to the fleet operator.

After fleet vehicles have been in service for several years, the operator is faced with the task of deciding when to replace these vehicles. This decision is based on the analysis of several parameters. These are salvage value, current interest rates, and maintenance costs. However, retiring the vehicle does not have to be the only alternative faced by the operator. The concept of Complete Vehicle Remanufacture (CVR) can be a cost-effective solution. The body of this paper will discuss the analysis of determining when to retire a certain vehicle from its' original manufactured state, as well as the feasibility of remanufacturing that vehicle and the steps involved in this process. The advantages to the CVR process such as economics, operating cost savings, vehicle reliability and the concern over liability and accident prevention will be discussed.

With the use of digital audio tape recorders and piezo accelerometers, a practical field-ready method of determining occupant loading has been developed for heavy truck and equipment ride evaluation. The primary objective in determining ride quality is to verify the accelerations transferred to the occupant through the seat. These accelerations can then be compared to occupant threshold limits to assist the engineer in determining ride quality. The acquisition of acceleration data can be done incrementally for each component of the vehicle, from the ground up to the seat cushion. This allows for an in-depth analysis of suspension and frame components which can then be used to fine tune the design. A secondary use of this method is to evaluate the interaction of contributing components to overall ride quality. Specifically, tires, shock absorbers, air bellows, spring rates, fifth wheel position and front axle position can be evaluated with this field ready method.

When faced with an engine failure, the initial problem to solve is how to repair it. This translates into the choices of; in-house or external repair. With current labor rates as they are, most operators cannot afford to rebuild an engine themselves. Parts acquisition, shop space, technical knowledge, tooling and the fact that in-house rebuilds do not carry a warranty all act to sway the operator to external sources for assistance. An additional, but equal, concern is how much will the engine cost to repair. The body of this paper will discuss the technology involved in producing remanufactured engines. Topics covered are cost analysis, remanufacture specifications and process and fleet operational logistics using remanufactured engines.

Emission standards derived to protect the environment have driven engine manufacturers to accelerate their efforts in engine emission development in order to meet the mandated standards. This paper will outline the current and upcoming emission standards, the technology involved in accomplishing the requirements and the solutions to in-service engines meeting their emission standards. The paper targets the fleet operator to provide a single source of information in an effort to alert them to upcoming requirements and what can be expected when specifying equipment for procurement. The technology discussed in this paper varies in its application for several engine makes and models. Since technology transfers from application to application it is vital that these ideas and concepts be explained.

For over a decade engine manufacturers have been pursuing alternative fuel strategies for vehicle powertrains. First came the discussion of fuel selection. Next, whether or not these alternative fuels can provide the utility offered by traditional diesel. Finally, the footrace of technology and hardware to provide utility, reliability and maintainability with the use of alternative fuels. Now the day has come where many alternative fuels are a practical reality. The body of this paper will discuss the utilization of natural gas as an alternative fuel. This paper targets the fleet operator in an effort to provide a single source of information in a concise format. A discussion of emission standards, engine operational strategies, component technology, fuel characteristics and the utility of using natural gas as a fuel will be addressed. The understanding of present and future engine development is of great importance to a successful fleet operation.

The need to reduce the injury to pedestrians that are run over or pinned beneath a bus is an ongoing concern for transit authorities and other operators. Occasionally, a pedestrian will be run over by the right rear wheel while exiting the rear door. This accident occurs in various scenarios such as when people exit the bus and become entangled in the door grab bars, or when they fall between the curb and the bus while it approaches or departs. With all scenarios, the S-1 Gard acts similar to a cow catcher, pushing the fallen pedestrian out and away from the rear tire. This paper will: outline various incident scenarios, evaluate the S-1 Gard's performance in a city environment, review installation of the guard as well as its maintenance requirements. The purpose of this paper is to bring to the attention of transit authorities and shuttle operators the overall value of this device.