Effect of Mechanical Properties On the Dynamics of Self-Oscillating Synthetic Vocal Folds

Abstract

Abstract This study focuses on the measured changes in dynamic behavior exhibited by eight synthetic vocal fold models with varying mechanical properties. Uniaxial tensile testing was conducted to determine changes in mechanical properties in materials made from silicone rubber and polydimethylsiloxane (PDMS) with varying mixing ratios. The results of the mechanical testing showed that the elastic modulus, E, varied from 20.6 kPa to 437.4 kPa, the measured Poisson ratios, \nu, spanned the range of 0.43 to 0.48, and the density ,?_VF, varied from 0.86 to 1.02 g/cm^3 across the eight samples. Vocal fold models were dynamically tested using a custom built experimental setup that supplied a heated and humidi?ed air ?ow to the synthetic vocal folds. The resulting sounds were recorded and analyzed in order to identify the change in fundamental frequency which spanned 66.8 Hz to 342.6 Hz across the eight samples. Additionally, a mathematical aeroelastic model of phonation was implemented to further investigate the relationship between the mechanical properties and phonation frequency. Finally, a proof-of-concept magnetic actuation method was demonstrated by using magnetic elastomers to deform the synthetic vocal folds through the use of an electromagnet.