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This study was conducted to develop and validate a multidimensional measure of shift quality as perceived by drivers during kick-down shift events for automatic transmission vehicles. As part of the first study, a survey was conducted among common drivers to identify primary factors used to describe subjective gear-shifting qualities. A factor analysis on the survey data revealed four semantic subdimensions. These subdimensions include responsiveness, smoothness, unperceivable, and strength. Based on the four descriptive terms, a measure with semantic scales on each subdimension was developed and used in an experiment as the second study. Twelve participants drove and evaluated five vehicles with different gear shifting patterns. Participants were asked to make kick-down events with two different driving intentions (mild vs. sporty) across three different speeds on actual roadway (local streets and highway).

Determination of the sound transmission loss (STL) of a vehicle component that has a large aperture, such as an air exhauster or an air extraction opening, always presents a challenge to an acoustics engineer. The complexity of the aperture's physical conditions cannot be easily solved with conventional, analytical or numerical methods. A systematic study of investigating the transmission loss characteristics of the large aperture is presented in this paper. Both conventional potential noise reduction predictions of large apertures and SEA simulations were performed. Transmission losses with different acoustic treatments were measured and predicted when using AutoSEA2. Finally, correlation between measured results and predications were developed. The ultimate goal of this study is to reduce the costly transmission loss measurements with correlated analytical estimations

A systematic benchmarking study was performed to investigate the acoustic performance of production floor coverings (i.e. carpets) of vehicles. A larger number of passenger cars including compact, mid-size, full size, and a truck were selected. The floor coverings were removed from these vehicles and evaluated both on absorption and sound transmission loss (STL) performances. The methodology used and the experimental results are presented in this paper. It was discovered that the design of the carpet is more important than the materials used. In addition, a carpet with highest absorption does not necessarily have the best STL and vice versa. However, an optimum design could achieve high performance in both categories.