ASA 124th Meeting New Orleans 1992 October

3pSP11. Modal analysis of a finite element simulation of the vocal folds.

David A. Berry

Ingo R. Titze

Dept. of Speech Pathol. and Audiol., Natl. Ctr. for Voice and Speech, Univ. of Iowa, Iowa City, IA 52242

Hanspeter Herzel

Humboldt Univ., Invalidenstr. 42, 0-1040 Berlin, Germany

Katharina Krischer

Princeton Univ., Princeton, NJ 08544

A modal analysis is made of a biomechanical simulation of the vocal folds. The dominant modes of the finite element simulation are computed by performing a principal components analysis on the time-varying nodal coordinates of the model. For simulations of normal phonation, the model---which contains many degrees of freedom---is reduced to essentially two dominant modes corresponding to those predicted by Titze and Strong [``Normal modes in vocal cord tissues,'' J. Acoust. Soc. Am. 57, 736--744 (1975)]. Additional modes are needed to explain simulations of pathological voice. The dominant modes from the various simulations will be displayed and discussed. The ability of traditional vocal fold models to capture these modes will also be considered. [This research was supported by Grant No. P60 DC00976-0X from the National Institutes on Deafness and Other Communication Disorders.]