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Updated: May 16, 2026
10:13
Hemi-laryngeal Setup for Studying Vocal Fold Vibration in Three Dimensions
Published on: November 25, 2017
Vibrational dynamics of vocal folds using nonlinear normal modes
Alan P Pinheiro1, Gaëtan Kerschen
1LaPSE Laboratory, Federal University of São João del Rei, Brazil. alan@ufsj.edu.br
Medical Engineering & Physics
|December 11, 2012
Summary
This study reveals complex nonlinear vibration patterns in vocal folds using a two-mass mechanical model. Findings include frequency-energy dependence and modal interactions, enhancing our understanding of voice production mechanics.
Area of Science:
- Biomechanics of voice production
- Nonlinear dynamics in biological systems
Background:
- Vocal fold vibration exhibits nonlinear characteristics, observed in physical models and theoretical studies.
- Understanding these nonlinear phenomena is crucial for voice production research.
Purpose of the Study:
- To investigate the nonlinear modal behavior of vocal folds using a two-mass mechanical model.
- To analyze the impact of structural nonlinearity on vocal fold tissue dynamics.
Main Methods:
- Application of nonlinear normal mode theory to a two-mass mechanical model of the vocal folds.
- Analysis of the free response of the conservative system at various energy levels for 16 subjects.
Main Results:
- Observed frequency-energy dependence, indicating that vibration frequency changes with energy input.
- Identified subharmonic regimes, modal interactions, entrainment, and bifurcations in vocal fold dynamics.
- Demonstrated complex nonlinear phenomena arising from the structural nonlinearity of vocal fold tissues.
Conclusions:
- The two-mass mechanical model effectively captures complex nonlinear dynamics in vocal fold vibration.
- Nonlinear normal mode theory provides valuable insights into the mechanics of voice production.
- Results contribute to a deeper understanding of the physical basis of voice disorders and therapeutic interventions.
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