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The primary function of a gauge and information display cluster is to report to the driver the current state of the different systems of the vehicle and particularly to report out of range performance conditions. This paper will examine one implementation of the instrument cluster as a node on the J1939 data link as it relates to that functionality. Traditionally clusters have received their information from a variety of sensors requiring a substantial number of connections. Once the cluster is installed in the vehicle, changing the configuration may only be accomplished by means of a hardware change.

The increasing complexity of the electrical and electronic systems on trucks requires a more sophisticated electrical control system. Replacing many of the discrete electronic controls and wiring with a central Electrical System Controller (ESC) allows for easier integration of system components and improved system response. The use of software control within the Electrical System Controller, provides opportunities for enhanced system capabilities and a fluid platform for future development. This paper examines the software architecture employed within an Electrical System Controller and also examines the factors that govern the software's design. These include a requirement for the ESC to be highly configurable to accommodate a variety of features desired by customers.

Engineering tests that do not impact business decisions waste time, budgets and morale. This paper will consider input and output information for the test process-specifically in vehicle dynamics and structural integrity labs. Uncontrolled test processes are unlikely to fulfill expectations. Conversely, the process may be closely defined in a widespread specification, and yet not answer the question at hand. Potential downstream impacts of loosely defined technical details will be discussed. Topics include selection of transducers, recording parameters, filtering and analysis techniques. Physics of common environmental loading are presented, along with implications for both the test plan and later use of the test data. Case studies as both a truck, bus and railroad test services provider and consumer will be discussed.

The increased use of power field-effect transistors instead of power relays for controlling electrical loads on vehicles has created an opportunity for the development of a software based virtual fuse. This development has several important aspects to the vehicle OEM. Not only will the cost of the fuse be saved along with the cost of the fuse holder, but also perhaps the largest cost associated with using a traditional fuse: the wiring to and from the fuse. In commercial vehicles, the variability of one vehicle to the next may force different circuits to occupy the same physical space on the different vehicles. These differing circuits may also require different values of fuse elements. Ensuring that the correct fuse value is installed under these conditions can be a difficult task at best. Having a software based virtual fuse that can be programmed to match the vehicle configuration can eliminate having an unprotected circuit due to an assembly error.

With the added complexity of vehicle multiplexed systems, the task of accurately diagnosing vehicle electrical failures is daunting at best. Integration of smart controllers into the electrical system provide the added flexibility and capability of detecting and monitoring operating conditions. This paper discusses one approach to detecting and displaying vehicle electrical diagnostic information either directly to the driver/technician via on-board driver information systems or indirectly via off-board service tools.

Increasingly, manufacturers are looking to computer simulation methods to accurately assess ride quality potential of new vehicle designs as they are being developed. This requires detailed multi-body dynamic models to be developed with sufficient fidelity to replicate ride relevant phenomenon. These models must have the capability to: Represent the distributed mass and elasticity of the vehicle structures (e.g. frame ladder, cab, and trailer). Include the non-linear behavior of shock absorbers and elastomeric components. Reproduce the fundamental system dynamics that influence ride. Provide output of the acceleration, velocity, and displacement measures needed to compute ride quality. This paper discusses the development of an ADAMS multi-body dynamic model of a tractor semi-trailer for use as a predictive tool in evaluating ride quality design improvements.

Effective application of human figure models to truck interior design requires accurate data on the postures and positions of truck drivers. Errors in positioning of figure models propagate to errors in reach, visibility, and other analyses. This paper describes methods used in a recent study to measure in-vehicle driving postures in Class 6, 7, and 8 trucks. A three-dimensional coordinate measurement machine was used to measure body landmark locations after a driver completed a short road course. The data were used to validate posture-prediction models developed in a previous laboratory study. Vehicle calibration, driver selection, and testing methods are reviewed.

This paper discusses an analytical tool that has been developed to predict what types of interior sound package treatments may be necessary in a truck cab to meet a predetermined target sound level at the driver location. The steps that were taken to develop this tool involved a combination of experimental measurement and analytical based studies. Measurements were conducted to identify the acoustic strengths of the major noise paths through which sound travels from outside to inside the truck. These findings were then used to develop a sound package that reduced the vehicle interior noise to meet the target. Measurements were primarily made on a chassis roll dynamometer with final road verification to substantiate the dynamometer data. Data obtained from these measurements were also used in the analytical model that predicts the impact of various acoustics parts in the vehicle, and has the capability to optimize the sound package treatment in the vehicle.