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The HELP Program and Crescent Demonstration Project is a bi-national multi-jurisdictional cooperative research and demonstration project involving the public and private sectors in an application of advancing technologies in the creation of an integrated heavy vehicle management system with applications to both highway and vehicle systems. This initiative is a leading example of the Intelligent Vehicle Highway Systems (IVHS) in commercial vehicle operations (CVO). The selected technologies are being integrated into a heavy vehicle management system. These technologies include: (1) automatic vehicle identification (AVI), (2) weigh-in-motion (WIM), (3) automatic vehicle classification (AVC), (4) data communication networks and systems integration. The program, initiated approximately eight years ago, consists of three phases which include assessing the feasibility of the concept, technical studies involving laboratory and field tests, and, lastly, the demonstration phase.

A fiber optic instrumented spark plug was used to make time-resolved measurements of the fuel vapor concentration history near the spark gap in a four-valve DISI engine. Four different bulk flow were investigated. Several early and late injection timings were examined. The fuel concentration at the spark gap was correlated with IMEP. Emissions of CO, HCs, and NOx were related to the type of bulk flow. For both early and late injection the CoVs of fuel concentration were generally lowest for the weakest bulk flow which resulted in a stable stratification. Strong bulk flows convected the inhomogeneities through the measurement area near the spark plug resulting in both large intracycle and cycle-to-cycle variation in equivalence ratio at the time of ignition.

Cylinder liner rotation (Rotating Liner Engine, RLE) is a new concept for reducing piston assembly friction in the internal combustion engine. The purpose of the RLE is to reduce or eliminate the occurrence of boundary and mixed lubrication friction in the piston assembly (specifically, the rings and skirt). This paper reports the results of experiments to quantify the potential of the RLE. A 2.3 L GM Quad 4 SI engine was converted to single cylinder operation and modified for cylinder liner rotation. To allow examination of the effects of liner rotational speed, the rotating liner is driven by an electric motor. A torque cell in the motor output shaft is used to measure the torque required to rotate the liner. The hot motoring method was used to compare the friction loss between the baseline engine and the rotating liner engine. Additionally, hot motoring tear-down tests were used to measure the contribution of each engine component to the total friction torque.

This paper provides an exposition of the basic and some refined inertial critical speed estimation formulas. A literature review of existing inertial formulas for estimating critical cornering speed were identified for the ultimate purpose of developing a useful, compact, and more accurate speed estimation formula. Background information is presented covering the general definitions and utility of critical speed formulas. First, as a point of reference, the basic critical speed formulas are derived. Included is a list of the key assumptions on which the basic formulas are based. It is shown that the basic formulas are founded on the fundamental principles of physics and engineering mechanics; namely, Newton's Second Law and centrifugal force.

This paper presents the results of original research conducted to evaluate the braking characteristics of passenger vehicles equipped with anti-lock braking systems (ABS) as a function of brake-pedal application force. The conditions studied in this paper are for braking on a dry, level roadway without any steering input. The objective of the paper is to study the effect of brake-pedal application force on the braking systems of common vehicles currently in-use. Comparisons are made between ABS and locked-wheel braking for each vehicle. The subject of this paper is part of the general topic of passenger vehicle dynamics and stability. Knowledge of how a vehicle performs under a variety of braking conditions is important for a variety of applications such as 1) intelligent vehicle highway systems, 2) vehicle stability and control, 3) vehicle dynamics, and 4) accident reconstruction.

This paper presents the results of original research conducted to evaluate the braking characteristics of passenger vehicles equipped with anti-lock braking systems (ABS) as a function of tire inflation pressure. The conditions studied in this paper are for braking on a dry, level roadway without any steering input. The objective of the paper is to study the effect of tire inflation pressure on the braking systems of common vehicles currently in-use. Comparisons are made between ABS and locked-wheel braking for each vehicle. The subject of this paper is part of the general topic of passenger vehicle dynamics and stability. Knowledge of how a vehicle performs under a variety of braking conditions is important for a variety of applications such as 1) intelligent vehicle highway systems, 2) vehicle stability and control, 3) vehicle dynamics, and 4) accident reconstruction.

This paper presents the results of original research conducted to evaluate the braking characteristics of passenger vehicles equipped with anti-lock braking systems (ABS) as a function of vehicle speed at the beginning of a braking maneuver. The conditions studied in this paper are for braking on a dry, level roadway without any steering input. The objective of the paper is to study the effect of vehicle speed on the braking systems of common vehicles currently in-use. Comparisons are made between ABS and locked-wheel braking for each vehicle. The subject of this paper is part of the general topic of passenger vehicle dynamics and stability. Knowledge of how a vehicle performs under a variety of braking conditions is important for a variety of applications such as 1) intelligent vehicle highway systems, 2) vehicle stability and control, 3) vehicle dynamics, and 4) accident reconstruction.

The basic process of spark ignition in engines has changed little over the more than 100 years since its first application. The rapid evolution of several advanced engine concepts and the refinement of existing engine designs, especially applications of power boost technology, have led to a renewed interest in advanced spark ignition concepts. The increasingly large rates of in-cylinder dilution via EGR and ultra-lean operation, combined with increases in boost pressures are placing new demands on spark ignition systems. The challenge is to achieve strong and consistent ignition of the in-cylinder mixture in every cycle, to meet performance and emissions goals while maintaining or improving the durability of ignitor. The application of railplug ignition to some of these engine systems is seen as a potential alternative to conventional spark ignition systems that may lead to improved ignition performance.

This paper covers briefly the theory of tire-road friction, coefficient of friction measurement techniques, and the vagaries of tire-road friction as they relate to critical speed estimation. A literature review of tire-road friction studies was conducted to identify the primary factors effecting the tire-road coefficient of friction. Background information is presented covering general definitions and the connection between the basic critical speed formulas and the coefficient of friction. The primary components of tire-road friction, adhesion and hysteresis, are discussed along with minor effects such as tearing, wear, waves, and roll formation. Common coefficient of friction field measuring techniques are described, including the skid-to-stop test and drag sled. Influential factors such as tire characteristics, tire inflation pressure, road conditions, and dynamic factors are reviewed.