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The major targets of transmission design today are higher efficiency, higher torque capacity and reduced size. Increasingly smaller transmissions with higher torque lead to increasing operating temperatures. This trend is further intensified by the use of noise abatement devices and improved aerodynamic body styling that reduces the airflow around transmissions. The friction in the transmission is responsible for temperature increase and efficiency losses, and thus the reduction of friction is the main measure in order to improve the efficiency and to keep the operating temperature low. The lubricant influences and is subjected to all changes of operating conditions. Higher operating temperatures result in a higher consumption of friction modifiers, extreme pressure and anti wear additives, higher corrosion and oxidation rates, and a thinner oil film separating the various components.

The efficiency of lubricated machine elements such as transmissions, crankcase engines, and hydraulic pumps depends strongly on the friction properties of the lubricant employed. For the design of modern, highly efficient lubricants it is thus essential to understand the influence of the components of the lubricating fluid in terms of film formation and consequent friction. The influence of Polyalkylmethacrylate (PMA) Viscosity Index Improvers on those important parameters has been studied by means of optical interferometry and friction testing. Low friction coefficients and positive contributions to the boundary film thickness of the lubricant were obtained when composition and architecture of the polymeric VII were appropriately designed.

This paper is the third in the series of documents designed to record the progress on the SAE Plug-in Electric Vehicle (PEV) communication task force. The initial paper (2010-01-0837) introduced utility communications (J2836/1™ & J2847/1) and how the SAE task force interfaced with other organizations. The second paper (2011-01-0866) focused on the next steps of the utility requirements and added DC charging (J2836/2™ & J2847/2) along with initial effort for Reverse Power Flow (J2836/3™ & J2847/3). This paper continues with the following: 1. Completion of DC charging's 1st step publication of J2836/2™ & J2847/2. 2. Completion of 1st step of communication requirements as it relates to PowerLine Carrier (PLC) captured in J2931/1. This leads to testing of PLC products for Utility and DC charging messages using EPRI's test plan and schedule. 3. Progress for PEV communications interoperability in J2953/1.

The noise and ride behavior of a vehicle can be significantly affected by vibrations transferred from the engine through the engine mounts to the chassis. Considering the engine, engine mounts, and chassis as individual components limits the potential gains on the overall vehicle performance. By describing the engine, engine mounts, and chassis as a vibrational system, emphasis can be placed on the capacity for engine mounts to improve the vibrational characteristics of a vehicle. The focus of this paper is on the role of engine mounts in the optimization process of vehicle vibrational and acoustic behavior. Passive, semi-active, and fully active engine mount designs are discussed. Characterization of the different effects of these types of mounts on noise and vibration performance is provided based upon analytical and experimental results.

The ride and noise behavior of a vehicle can be significantly affected by vibrations transferred from the engine to the chassis through the engine mounts. For this reason, special attention has to be paid to the design of the engine mount system right from the beginning of a new car development program. Only optimizing the engine mount while considering it as an isolated component limits the potential gains in regard to the overall vehicle performance. Therefore, right from the conception phase, the mounting system has to be considered as an integral part of the vehicle vibrational system. With the suggested approach, based on analytical and experimental results, the optimization of the mount system can lead to a good overall vehicle performance at low cost. The focus of this paper is placed on the role of engine mounts in the optimization process of the vehicle vibrational and acoustic behavior.

The ride and noise behavior of a vehicle is significantly affected by vibration transferred from the engine to the chassis through the engine mounts. In this paper conception and design strategies for engine mount systems based upon calculation and experimental methods are discussed. Analyses for static and dynamic engine loads and for idle shake vibrations are presented. The finite element analysis is applied to optimize a mount's rubber spring geometry. Furthermore, the role of the transfer path analysis in the optimization of an engine mount system is illustrated. Passive and semi-active engine mounts that significantly improve the isolation of the idle shake vibration will be discussed. Finally, fully active vibration absorbers which can be applied to solve noise problems, even at a late stage of a new car development program will be presented.

A vehicle's structure vibration leads to perceivable accelerations at the steering wheel, the seat rails and the floor panels; additionally, these vibrations cause structure borne noise which contributes to the sound pressure level in the passenger's compartment. The perceivable structure accelerations and the sound pressure level constitute criteria for evaluating a vehicle's noise and vibration behavior. Consequently, improving the noise and vibration behavior is tantamount to reducing the vibration amplitudes of the vehicle structure. The operating engine causes engine mount forces which provoke the structure vibration. After the engine mount forces are calculated, the structure vibrations are simulated with a vehicle structure model described by transfer functions that relate the engine mount forces to the accelerations of all selected structure points where the vibration is supposed to be analyzed.

Polyalkylmethacrylates (PAMAs) are widely used as viscosity index improvers and dispersant boosters in engine, transmission and hydraulic oils. They have been shown to be able to adsorb from oil solution on to metal surfaces, to produce thick, viscous boundary films. These films enhance lubricant film formation in slow speed and high temperature conditions and thus produce a significant reduction of friction and wear. In a recent systematic study a range of dispersant and non-dispersant PAMAs has been synthesized. The influence of different functionalities, molecular weights and architectures on both boundary film formation and friction has been explored using optical interferometry and friction-speed charting. From the results, guidelines have been developed for designing PAMAs having optimal boundary lubricating properties. In the current paper the film forming, friction and wear properties of solutions of two functionalised PAMAs is first described.

Viscosity index improvers based on poly(alkyl methacrylates) as well as polyolefins have been well known to the industry as key additives to formulate lube oils for decades. Recent efforts to combine these two chemistries to prepare well-defined comb polymer architectures have led to a performance breakthrough. Specifically, the concept of temperature dependent comb polymer coil expansion and collapse allows to achieve extraordinary viscosity temperature properties. Viscosity indices and thickening efficiencies are well beyond the levels achievable by conventional chemistries at the same shear stability level. After a general introduction of viscometric key properties, the paper describes synthetic pathways towards these novel comb polymers. Standard radical polymerization of polyolefin macromonomers with alkyl methacrylate backbone comonomers is the most straightforward process for their preparation, and allows for an easy transfer to manufacturing.