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An advanced Variable Valve Actuation (VVA) system is optimized for response time in order to provide robust switching at high engine speeds. The VVA system considered is Cylinder Deactivation (CDA) for the purpose of improving fuel economy. Specifically, a Switching Roller Finger Follower (SRFF) on a Dual Overhead Camshaft (DOHC) engine is optimized for cylinder deactivation. The objective of this work is to (1) improve the latch response time when the system response is the slowest, and (2) balance the “ON” and “OFF” response time. A proper tradeoff was established to provide the minimum switching time such that deactivation and reactivation occurs seamlessly and in the right sequence. The response time optimization is accomplished while maintaining the existing packaging space of the overhead. A camshaft with a single lobe per SRFF device on a type II valvetrain was used as the baseline configuration for this study.

A part-task simulator has been developed which concentrates on the functions related to transmission gear shifting in heavy duty trucks. By avoiding the complexity of full-feature simulators, a simple and cost-effective tool has been produced which allows training of the driver and study of the powertrain in a controlled environment. The components and operation of this new simulator are described, along with present and potential applications.

An existing pass by noise data acquisition system was upgraded to provide the sophisticated data analysis techniques and test site efficiency required to comply with the current and future drive by noise regulations. Use of six sigma tool such as voice of the customer helped in defining the customer requirements which were then translated into the desired engineering characteristics using QFD. Pugh concept matrix narrowed down the best option suitable for the test site modifications taking into account the critical constraints such as test complexity, system cost & transparency to the existing drive by noise setup. Features of the new system include data telemetry, frequency analysis, portability and efficient data management through the use of advanced data acquisition system. Wireless mode of the data transmission helped significantly avoid most of the test site modifications, which in turn helped to reduce the overall system implementation cost.

Eaton has been working on technologies for cost effective, reliable and safe Automated Mechanical Transmissions (AMTs) since the mid 1970's. The company has introduced three different systems since the late 1980's, but all three systems were constrained by the lack of precise engine speed control during shifting. With the advent of electronic engine controls the constraint has been removed and precise engine speed control during shifting can be easily accomplished. The result is a simplified system that is powerfully intelligent and fully capable of automatic shifting i.e., the transmission system determines when to shift and executes the shift without any driver inducement across the broad spectrum of truck usage. This paper discusses some of the AMTs available to the truck market, showing how the system benefits both the OEM and the end user.

Commercial vehicle operators and governments around the world are looking for ways to cut down on fuel consumption for economic and environmental reasons. Two main factors affecting the fuel consumption of a vehicle are the drive route and the driver behavior. The drive route can be specified by information such as speed limit, road grade, road curvature, traffic etc. The driver behavior, on the other hand, is difficult to classify and can be responsible for as much as 35% variation in fuel consumption. In this work, nearly 600,000 miles of drive data is utilized to identify driving behaviors that significantly affect fuel consumption. Based on this analysis, driving scenarios and related driver behaviors are identified that result in the most efficient vehicle operation. A driver assistance system is presented in this paper that assists the driver in driving more efficiently by issuing scenario specific advice.