Experimental study of self-oscillations of the trachea–larynx tract by laser doppler vibrometry

摘要: We study the acoustical and mechanical vibration fields generated when Italian speakers emit vowels in order to individuate role played by trachea speech production mechanism. Specifically, experimental series regard vibrations along trachea–larynx tract measured using non-contact laser Doppler vibrometry (LDV), contemporaneously we acquire field means of a set microphones. The apparatus consists two LDV systems microphones: this allows have synchronized recorded signals be compared, thus get information about propagation. lasers are pointed thorax scanning tracheal tract. observe that displays significant self-oscillations cannot avoided production. In particular, clear self-oscillation at frequency related pitch is extracted independent component analysis. Thanks systems, oscillations start before those larynx acoustic oscillations, indicating oscillation upward propagating. These experiments support hypothesis further hydrodynamic instability should advocated mechanism level. Moreover, pitch, typically looking inter-times signals, directly obtained measuring trachea.