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An electro-mechanical variable speed transmission (eVT) is proposed for hybrid electric vehicles. The transmission is comprised of a pair of planetary gear trains interconnected with two electric machines and clutches. With on-board energy storage devices, the transmission combines, in a compact unit, independent speed-ratio control and power regulation between the engine and drive wheels. It offers a highly integrated, efficient and low cost solution to hybrid electric vehicles. Operating principles of the transmission were outlined. Virtual transmission and vehicle prototypes were built with EASY5. Simulations were conducted to evaluate its performance in context of a hybrid electric vehicle. Comparisons were made against non-hybrid vehicles equipped respectively with eVT and four-speed automatic transmission, and against the production hybrid vehicle Prius. Results showed superior performance of the proposed eVT in hybrid vehicle.

Design of suspension systems for Heavy Trucks is always challenging due to the heavy loads the system is exposed to and the long life requirements for the total system. Historical solutions were over designed structures to get the needed life and reliability. This always meant heavier parts. In today's economy, the vehicle weight of commercial heavy trucks is a very important feature for our customers and the end user. Lighter, well-designed suspension components provide better ride quality to the drivers through lower un-sprung weight, lower initial costs and greater payloads. The latest available structural optimization techniques are a business requirement for tomorrow's products. This paper describes the developed methodology used by DANA Engineers to design a weight optimized upper control arm for Commercial Heavy Trucks in step by step fashion. The method starts with determining the loads on the component part.

An electro-mechanical infinitely variable transmission (eVT), comprising a pair of planetary trains interconnected with two electric machines and clutches, has been proposed. The transmission leverages the advantages of an output power-split configuration for low-speed operation and a compound power-split configuration for high-speed operation. It is capable of being operated in a number of operating modes including an eVT only mode and a hybrid mode when equipped with on-board energy storage devices. The transmission provides a compact, highly efficient and potentially low cost driveline solution for both conventional vehicles and hybrid electric vehicles. A virtual transmission prototype was built in EASY51. A base vehicle model was also constructed in EASY5 environment with Ricardo Powertrain Library components.

The Advanced Vehicle Concepts Team (AVCT) at the University of Idaho (UI) modified a 2002 Ford Explorer to meet the objectives of the 2002 FutureTruck competition. The challenge was to improve fuel economy, decrease emissions, perform work safely, provide a high quality education, increase public awareness, and project a positive image. AVCT used a business-oriented, multi-disciplinary approach to address the general objectives. For the performance objectives, the team used a combination of simulations, experiments, and modeling. The resulting configuration is a low voltage, mild parallel hybrid incorporating a 4.0-liter, V6 Ford engine and a direct current, electric motor. The first prototype resulted in a 22% increase in fuel economy and a substantial reduction in greenhouse gas emissions except for hydrocarbons. An engine sensor malfunction was the suspected cause of increased hydrocarbon emissions.

Three currently available hydromechanical transmissions have been considered, all targeted at the off-highway market. For the purposes of this paper, these are designated Types “A”, “B” and “C”. Each unit has discreet qualities and types of application, and further differences will be highlighted. To provide a reference, a conventional six speed power-shift transmission has also been included, with a down-stream range change unit, held in “Hi” range; designated type “X”. The problem Ricardo have addressed in this paper is how to compare and contrast the qualities of these units for a potential user, who may not be familiar with off-high-way applications. The example considered in this study is a mobile rough-terrain crane manufacturer, contemplating a 25 tonne machine with a 193 kW engine and an on-highway max. speed of 75 kph.

The design objective of the Spicer S400-S axle program was to develop a light weight, lower torsional vibration, long life tandem drive axle for the heavy truck industry. This was accomplished with the incorporation of a number of new product features and technical advancements, both in design and manufacturing. These include: reduced standouts for improved interaxle driveline angles use of finite element analysis fixed pinion mounting optimization of lube flow and direction of lubrication optimized gear design for improved strength and noise reduction. This paper focuses on these features and also on the development process for the axle, including the use of simultaneous engineering. Utilizing simultaneous engineering, the S400-S was developed from concept to full production in fifteen months.

A math model of vehicle handling demonstrates the desirability of a controllable biasing device for all wheel drive (AWD) cars. Several devices can provide the traction benefits of AWD. However, there is a potential for shifting wheel torque during braking and thereby destabilizing the vehicle. A controlled clutch is shown to improve traction while retaining the nominal stability of the vehicle in braking.