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The next generation in Europe of city bus control systems design will focus on system data exchange, power control and diagnostic for vehicle electronics. This will be the basis for improved functionality of city vehicles in order to fulfill any government regulations, reduced development cost, and allow an increased flexibility in the new functions capability. The focus of this paper is to review the principle design structure of ACTIA's new multiplex control system; door control, lights control, extension to the J1939 standard, instrumentation and their applications.

Every year the trucking industry demands lighter weight and lower cost truck components. But it is very difficult to achieve both these targets. This paper describes the example of a suspension system design which was conducted by computer simulation, so called CAE. The computer simulation by FEM was used completely to decide the detailed shape of each part. This paper also introduces a casting method to strengthen the aluminum alloy cast using high pressure during casting. By using this method, products have a precise metallographic structure. As a result, both the development cost and period were reduced by over the half the time required of the current system and lighter and strong parts were created.

A generic articulated heavy vehicle model, applied to a tractor semi trailer combination is modelled on an approach characterised by simplicity. Yet, the handling characteristics accuracy serves well within the frequency domain of interest. Possessing the capacity of performing in real time simulation up to the limits of yaw and roll stability, its simplicity derives advantages offering effective parameter variation possibilities at an elevated educational level. As an example, better understanding of the expected wheel angle deviation from the current wheel spindle angle is achieved through an extension of the model. Validated against field experiments of lane change manoeuvring under high friction conditions up to the limit of roll stability, it also compan?s well against a more complex computer model.

An In-Vehicle Data Acquisition/Monitoring Device (Data Logger) has been developed to be used for evaluating the performance of alternators during vehicle operation. It can be linked to other controllers and electronic devices for exchange of information through the use of a serial communication port. By utilizing a microcontroller, eight analog and three TTL level signals are measured and recorded in non-volatile EEPROM memory devices. The system measures temperatures of critical components, system voltage and rotational speed.

The flexibility of flat bed trailers is shown to be an important consideration in determining the static roll threshold for a loaded Class 8 tractor trailer. The development of an easy to use static roll threshold model using Microsoft® Excel's nonlinear equation solution capability provides a tool that should be useful to the trailer designer, dock loading manager and the traffic safety manager responsible for the training of drivers. It can be seen for low stiffness flat bed trailers that the trailer torsional stiffness is a more important parameter than typical suspension or tire stiffness. Further, even for “stiff” flat bed trailers the use of the rigid body roll criteria (T/2h) or the 2-D “planar” model can produce significant error in many practical loading configurations.

A closed-loop articulated vehicle-driver model, incorporating the path errors, lateral accelerations of the two units and the rate of steering, is proposed to study the directional control behavior of the driver. The closed-loop driver-vehicle model is formulated upon integrating the yaw-plane model of a five-axle articulated vehicle and a comprehensive driver model. The driver model, incorporating the delays associated with the limb movement and muscle activities, is developed with an objective to minimize the lateral acceleration of vehicle, and the lateral position and orientation errors between the previewed and the actual path of the tractor. Various parameters required to describe the driver's contributions are identified through minimizing a weighted performance index subject to an array of limit constraints established from the reported data.

Relative rollover conditions of a heavy vehicle are analyzed to establish an array of potential dynamic rollover indicators towards development of an early warning device. A relative roll instability indicator defined as Roll Safety Factor (RSF) is proposed and shown to be a highly reliable indicator regardless of vehicle configurations and operating conditions. The correlation of various potential rollover indicators with the roll safety factor are then investigated for a 5-axle tractor semi-trailer combination using a comprehensive directional dynamic analysis model to determine the reliability of the proposed indicators over a range of operating conditions. The indicators are further examined in terms of measurability, lead time, and potential for application in an early warning system. The study shows that the trailer lateral acceleration and axle roll angles are closely correlated with the RSF.

Hundreds of millions of micromachined, piezoresistive Manifold Absolute Pressure (MAP) sensors have been produced to reduce pollution and improve fuel efficiency in engine control systems. Other vehicle applications for micromachined pressure sensors include monitoring turbo pressure, barometric pressure, fuel tank leakage, fuel rail pressure and tire pressure. Exhaust gas recirculation and even door compression for side impact detection are employing micromachined silicon pressure sensors. Piezoresistive pressure sensors have dominated the automotive market to date. Practical micromachined capacitive pressure sensors have recently been developed and could replace the piezoresistive sensor in many applications. This paper will examine the advantages of both pressure sensing technologies, and discuss applications that an inexpensive capacitive pressure sensor will open up.

An automotive Coolant Level Sensor has been developed which eliminates the diffusion of water through the housing. This enables the Coolant Level Sensor to survive in high temperature/pressurized environments.

The PACCAR Digital Message Center (DMC) is a truck computer with a 40-character vacuum-fluorescent display in the dash panel. Designed to OEM specifications, it serves to integrate the many data display requirements of heavy trucks into a single device. To meet customers' ergonomic expectations, consideration was given to information navigation, the display technology, the number of keys, the size of each key, the key labeling, and the keys' tactile feedback. The product was designed to be used by operators (clock/alarm, messaging, fuel economy information), service technicians (diagnostics and maintenance) and fleet managers (trip recording and fuel management). Configurability and software upgradeability were also important considerations.

This technical paper discusses the need for a retrofit program using improved technology to eliminate the use of axle nuts having the potential for failure. A review of the history of wheel end problems on highway trailers is also a portion of this presentation. Knowledge of newly perceived operational conditions will be presented along with recommendations on how they might be addressed. With review of this material, those interested in highway safety will be apprised of up-to-date information that will enable appropriate remedial action to be initiated.

Presented in this paper is a new multiplex communications technology that economically permits a two-way transfer of information (data) between a tractor and trailer(s) through the standard SAE J560 connector. Power Interval Communications Technology (PICT) is a single wire, serial communication system that is transmitted over the existing turn signal circuit. This paper will show the basic approach of the PICT system and the major advantages it offers. PICT allows the use of the current SAE J560 connector to provide an in-cab trailer ABS fault indication. PICT, transmitted over the turn circuit, is compatible with all tractor and trailers, old and new, because this circuit is common to all vehicles. PICT is a very economical solution because no twisted pair communications wiring is required, no in-line switched communications techniques are required, no sophisticated interface circuitry is required, and no additional connections are required between the tractor and trailer.

A major task of road and airfield maintenance for transportation departments in the Northern United States and in cold regions globally is snow removal. In addition, there is a service industry built on snowplow equipped light trucks to remove snow from vehicle serviceways and parking lots. Thus, a source of stresses on a truck frame are the forces applied by the plow. Unfortunately, very little research has been performed to provide design models that will predict these forces. In this paper, both theoretical and experimental work on developing expressions for snowplow forces will be discussed.

In this paper, the features of V3300 heavy-duty diesel engine series and the technologies to achieve the concepts are introduced. V3300 series is the vertical water-cooled 4 cycle IDI diesel engine for agricultural and industrial use. Its output is the highest in our company's IDI diesel engines. V3300 series was developed based on the concepts of our conventional series (low vibration, low noise, clean exhaust emissions and good fuel efficiency). V3300 series adopts 3 valves system for the first time in agricultural and industrial diesel engines. This 3 valves system is composed of 2 intake valves and 1 exhaust valve per cylinder. V3300 series also adopts the new combustion system which succeeded to the KUBOTA's original combustion system. The volumetric efficiency, the fuel efficiency and the exhaust emission performance are improved by these systems. The comfort level is achieved by reduction of the vibration and the noise by adoption of the built-in balancer.

MAN and Shell have jointly investigated the effect of fuel properties on exhaust emissions from advanced engine technologies. MAN Nutzfahrzeuge AG, the Austrian subsidiary Steyr Nutzfahrzeuge AG and Deutsche Shell AG started this bilateral cooperation in 1990 with the objective of identifying key fuel properties that influence emissions from a MAN heavy-duty engine meeting the EURO-I legislation. The intention of that investigation was to determine the effect of cetane number, total and poly-aromatics content and backend distillation [T90] on particulates and gaseous emissions. In parallel both companies participated in the EPEFE (European Program on Emissions, Fuels and Engine Technologies) program which provided a broader understanding of fuel effects on emissions with different engine technologies under European test conditions.

A program to explore the effects of natural and additive-derived cetane on various aspects of diesel performance and combustion has been carried out. Procedures have been developed to measure diesel engine fuel consumption and power to a high degree of precision. These methods have been used to measure fuel consumption and power in three heavy-duty direct-injection diesel engines. The fuel matrix consisted of three commercial fuels of cetane number (CN) of 40-42, the same fuels raised to CN 48-50 with a cetane improver additive, and three commercial fuels of base CN 47-50. The engines came from three different U.S. manufacturers and were of three different model years and emissions configurations. Both fuel economy and power were found to be significantly higher for the cetane-improved fuels than for the naturally high cetane fuels. These performance advantages derive mainly from the higher volumetric heat content inherent to the cetane-improved fuels.

The 70 Series 4WD tractors offered by John Deere has been replaced by a new 9000 product line as part of the continuous improvement process to meet customer needs and provide a product with maximum value to our customers. The new model lineup is 260, 310, 360, and 425 engine HP. All models are powered by John Deere engines with the largest 3 models using the new 10.5L and 12.5L engines. The new line of 9000 Series tractors is a styled tractor family which uses many of the 8000 Series Row Crop tractor concepts and designs. This new product line provides improved operator comfort, enhanced operator conveniences, and simplified serviceability.

Importance of detecting obstacles around construction machines increase rapidly. The millimeter-wave radar is the most useful sensor to keep to detect obstacles in the current technologies. because of its good performance under severe conditions. The signal processing algorithm of this radar is developed, for the using in working conditions by means of eliminating signal fluctuations and instabilities caused by its environments. The developed millimeter-wave radar has a reasonable performance, for example, detecting the rear side of automobiles and many types of construction machinery from the distance of 100m.

Stress affects each of us regardless of who we are or what we do. Our bodies have developed intricate systems to respond to stress. These systems were developed during human kinds infancy to assist us to respond to life threatening situations. In today's world we face much different threats than our early counterparts. Regardless, our bodies haven't caught up to our current lifestyles. Our body systems still react to a deadline the same as a Saber Toothed Tiger attack. Until it catches up we need to learn about these responses and what we can do to control them.

A new series of compact excavators has been developed with enhanced performance to compete against tractor loader backhoes. At the heart of this design is a unique hydraulic circuit that provides the necessary hydraulic pressures and flow rates. This circuit also provides the simultaneous operation of many vehicle functions while minimizing the pump capacity requirements. This feature has been termed multifunction operation. The hydraulic circuit and its development are detailed.