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In order to introduce Dana's Variglide Continuously Variable Planetary (CVP) technology to the mobility industry, Dana has produced demonstrator transmissions for use in a rear wheel drive C-class car and in a fork lift truck. The intention is to illustrate how the CVP can be combined with conventional transmission technology to produce either a continuously variable transmission with the ratio range comparable to that of the latest step ratio transmissions, or used in a simple IVT configuration for off-highway applications. The co-axial design of the CVP allows it to package well into current drivetrain solutions. The ratio control of the device is fast, precise, and stable and the CVP does not require high power consumption for clamping. Multiple power flow configurations of the CVP are shown to blend well with current conventional transmission technology as well as future hybrid configurations.

This paper describes advances in variable speed supercharging, including benefits for both fuel economy and low speed torque improvement. This work is an extension of the work described in SAE Paper 2012-01-0704 [8]. Using test stand data and state-of-the-art vehicle simulation software, a NuVinci continuously variable planetary (CVP) transmission driving an Eaton R410 supercharger on a 2.2 liter diesel was compared to the same base engine/vehicle with a turbocharger to calculate vehicle fuel economy. The diesel engine was tuned for Tier 2 Bin 5 emissions. Results are presented using several standard drive cycles. A Ford Mustang equipped with a 4.6 liter SI engine and prototype variable speed supercharger has also been constructed and tested, showing low speed torque increases of up to 30%. Dynamometer test results from this effort are presented. The combined results illustrate the promise of variable speed supercharging as a viable option for the next generation of engines.

Infinitely variable transmission (IVT) characteristics are typically obtained by utilizing a planetary gear set in a split-power transmission configuration. The spherical traction CVT developed by Fallbrook Technologies is kinematically analogous to a variable planetary gear set. The combinations of multiple inputs, outputs, and different internally parallel architectures combine to create hundreds of CVT, IVT, and/or split-power configurations. The variable planetary configuration is inherently power dense and creates a compact, low cost IVT, potentially without the need for dual paths. The control of this novel variator is inherently stable because ratio control is independent of load.

A new rolling traction CVT design based on spherical torque transfer components has been developed by Motion Technologies, LLC. Improved efficiencies and significantly improved power densities have been demonstrated. Ratio control of this CVT is very simple, in contrast with more complex controls required for other rolling traction type CVTs. Both the single cavity and dual cavity designs of the Motion CVT have coaxial input and output shafts. The input and/or output may also be offset to accommodate other automobile drivelines. These characteristics, combined with low manufacturing cost, make the Motion CVT a very reasonable option for automotive and other vehicle applications.

The 1990's have witnessed widespread proliferation of inexpensive, inertia-loaded chassis dynamometers. Previously, chassis dynos were not accessible to the general public. Thanks to this proliferation, there is now a core audience of knowledgeable auto enthusiasts who have chassis dyno results for their cars, but little understanding of the difference between these results, SAE net HP and actual power delivered to ground. This audience consists of trend leaders and early adopters, the customers most sought after by the OEMs. This paper derives the loss sources present in these tests, and illustrates the difference between the different reference frames for power measurement.