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Since the invention of the internal combustion engine, the contact between piston ring and cylinder liner has been a major concern for engine builders. The quality and durability of this contact has been linked to the life of the engine, its maintenance, and its exhaust gas and blowby emissions, but also to its factional properties and therefore fuel economy. While the basic design has not changed, many factors that affect the performance of the ring/liner contact have evolved and are still evolving. This paper provides an overview of observations related to the lubrication of the ring/liner contact.

This paper describes the development of a generic test cell software designed to overcome many vehicle-component testing difficulties by introducing modern, real-time control and simulation capabilities directly to laboratory test environments. Successfully demonstrated in a transmission test cell system, this software eliminated the need for internal combustion engines (ICE) and test-track vehicles. It incorporated the control of an advanced AC induction motor that electrically simulated the ICE and a DC dynamometer that electrically replicated vehicle loads. Engine behaviors controlled by the software included not only the average crankshaft torque production but also engine inertia and firing pulses, particularly during shifts. Vehicle loads included rolling resistance, aerodynamic drag, grade, and more importantly, vehicle inertia corresponding to sport utility, light truck, or passenger cars.

Until recently, U.S. government efforts to dramatically reduce emissions, greenhouse gases and vehicle fuel consumption have primarily focused on passenger car applications. Similar aggressive reductions need to be extended to heavy vehicles such as delivery trucks, buses, and motorhomes. However, the wide range of torques, speeds, and powers that such vehicles must operate under makes it difficult for any current powertrain system to provide the desired improvements in emissions and fuel economy. Hybrid electric powertrains provide the most promising, near-term technology that can satisfy these requirements. This paper highlights the configuration and benefits of a hybrid electric powertrain capable of operating in either a parallel or series mode. It describes the hybrid electric components in the system, including the electric motors, power electronics and batteries.

Hybrid electric propulsion has matured to the point that it is in production for small vehicle platforms. Work still needs to be done on adapting the technology for heavier weight classes. The dramatic increase in fuel efficiency, the exhaust emission reductions and the availability of an on-board source of high-power electrical energy for auxiliary systems are important for the commercial and military market. The U.S. Army's National Automotive Center (NAC) in Warren, MI, and United Defense L.P. (UDLP) in San Jose, CA, have developed a series hybrid 20-ton tracked military vehicle to explore this technology. This paper describes this work and its application to the other hybrid programs.

The utilization of commercially based technologies has the ability to greatly reduce the time and cost of military vehicle development. Commercially based technologies also enable the transition of a high level of capability into the military vehicle inventory and to the Army's ultimate customer, the soldier. The Army's National Automotive Center (NAC) has created SmarTruck, a light truck platform enhanced for military concept exploration. SmarTruck is outfitted with telematics, safety, and non-lethal weapon systems technology. It is a prime example of the NAC's central focus, which is dual-use commercial technology transfer. At the core of success for SmarTruck is the application of telematics technologies including embedded diagnostics, advanced electronic architectures, tele-maintenance, and wireless communications.

This paper will describe the Army's Vehicle Intelligence Program and discuss some of the VI technologies being considered for use within the Army's Tactical Wheeled Vehicle fleet. It will describe some initial modeling efforts that focus on the fuel efficiency impacts of selected VI technologies and will suggest the impacts of an integrated and networked fleet with regard to logistics. Lastly, it will identify several areas of AVIP research that are being considered in the near term. All of these programs impact directly on the 21st Century (21T) Truck program. [1]