Search

Your search keyword '"Lawless, Martin S."' showing total 23 results
Start Over Author "Lawless, Martin S."
23 results on '"Lawless, Martin S."'

2. Impact of wearing a head-mounted display on localization accuracy of real sound sources

Author

Poirier-Quinot David and Lawless Martin S.

Subjects
binaural, localization, head-mounted display, Acoustics in engineering. Acoustical engineering, TA365-367, Acoustics. Sound, QC221-246
Abstract

For augmented reality experiences, users wear head-mounted displays (HMD) while listening to real and virtual sound sources. This paper assesses the impact of wearing an HMD on localization accuracy of real sources. Eighteen blindfolded participants completed a localization task on 32 loudspeakers while wearing either no HMD, a bulky visor HMD, or a glass visor HMD. Results demonstrate that the HMDs had a significantly impact on participants’ localization performance, increasing local great circle angle error by 0.9°, and that the glass visor HMD demonstrably increased the rate of up–down confusions in the responses by 0.9–1.1%. These results suggest that wearing an HMD has a sufficiently small impact on real source localization that it can safely be considered as an HMD-free condition in most but the most demanding AR auditory localization studies.

Published
2023
Full Text
View/download PDF

11. Application of a dual stage exhaust system using expansion chambers for Formula SAE.

Author

Philipson, Yuval and Lawless, Martin S.

Subjects
EXHAUST systems, RESONATORS, ACOUSTIC filters, ITERATIVE methods (Mathematics), GAS flow
Abstract

Typical vehicle mufflers utilize a series of expansion chambers and resonators to reduce engine noise. Both components behave like acoustic filters by changing the impedance of the exhaust system. Expansion chambers act as low-pass filters, which mitigate noise above a cut-off frequency determined by the geometry of the chamber. Meanwhile, resonators target specific frequencies to attenuate like a notch-filter. The present work explored tuning a muffler system containing an expansion chamber and a resonator to reduce engine noise of a Formula SAE racecar. The exhaust system design was completed using custom MATLAB scripts, Ricardo WAVE, and iterative prototyping. After determining the frequencies where the engine produced maximum sound output, the components were fabricated to damp the amplitude of the offending frequencies. The transmission loss of the prototype exhaust system was tested in an anechoic chamber by measuring the frequency responses of each separate component and the entire system. Based on this experimentation, the exhaust system had an expected overall transmission loss of 25 dB. Installed on the vehicle, the operational transmission loss was 17 dB. This discrepancy is likely due to operational conditions that could not be replicated in the laboratory experiment, such as increased temperature and gas flow. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

23. HRTF Performance Evaluation : Methodology and Metrics for Localisation Accuracy and Learning Assessment

Author

Poirier-Quinot, David, Katz, Brian F.G., Stitt, Peter, and Lawless, Martin S. S.

Subjects
Technology & Engineering
Abstract

Through a review of the current literature, this chapter defines a methodology for the analysis of HRTF localisation performance, as applied to assess the quality of an HRTF selection or learning program. A case study is subsequently proposed, applying this methodology to a cross-comparison on the results of five contemporary experiments on HRTF learning. The objective is to propose a set of steps and metrics to allow for a systematic assessment of participant performance (baseline, learning rates, foreseeable performance plateau limits, etc.) to ease future inter-study comparisons.

Published
2020

Catalog

Books, media, physical & digital resources
See catalog results