Effects of controlling chaotic vocal fold vibrations on finite element generated vowels

Abstract

Lumped mass models of the vocal folds have been widely used to analyze the physics of human phonation. This is a strongly non-linear process that results in regular selfoscillations of the vocal folds. However, various factors such as polyps, excessive subglottal pressure, etc., can alter such motion and make it chaotic. Ideally, it would be possible to use a smart material to control the dynamics of the vocal folds and restore its regularity. In this paper, we will see the effects of such a control strategy on the generation of vowels. The chaotic and the controlled train of glottal pulses will be imposed as boundary conditions at the glottis of a three-dimensional model of the vocal tract (VT). Then, the finite element method will be used to solve the wave equation inside the VT and the spectra and sound of the generated vowels will be compared to check the performance of the chaos control strategy on phonation.