Vocalization Control of a Mechanical Vocal System under Auditory Feedback

2002 ◽  
Vol 14 (5) ◽  
pp. 453-461 ◽  
Author(s):  
Yoshio Higashimoto ◽  
◽  
Hideyuki Sawada ◽  

We are developing a mechanical model of a human vocal system based on mechatronics technology. Although various ways of vocal sound production have been actively studied, mechanical construction is considered to advantageously realize natural vocalization with its fluid dynamics. In voice generation, analysis of the behavior of the vocal cords and the vocal tract are required in a mechanical system. Furthermore, fluid mechanics are less stable, making control more difficult. Several motors are used to manipulate the mechanical vocal system. A neural network works to establish relations between motor positions and produced vocal sounds by auditory feedback in the learning phase. In speech performance, the mechanical system is able to vocalize while vocal pitches and phonemes are adaptively controlled by auditory feedback control. This paper presents the construction of a mechanical vocal system and its adaptive acquisition of vocalization skills.

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Christopher Bergevin ◽  
Chandan Narayan ◽  
Joy Williams ◽  
Natasha Mhatre ◽  
Jennifer KE Steeves ◽  
...  

Khoomei is a unique singing style originating from the republic of Tuva in central Asia. Singers produce two pitches simultaneously: a booming low-frequency rumble alongside a hovering high-pitched whistle-like tone. The biomechanics of this biphonation are not well-understood. Here, we use sound analysis, dynamic magnetic resonance imaging, and vocal tract modeling to demonstrate how biphonation is achieved by modulating vocal tract morphology. Tuvan singers show remarkable control in shaping their vocal tract to narrowly focus the harmonics (or overtones) emanating from their vocal cords. The biphonic sound is a combination of the fundamental pitch and a focused filter state, which is at the higher pitch (1–2 kHz) and formed by merging two formants, thereby greatly enhancing sound-production in a very narrow frequency range. Most importantly, we demonstrate that this biphonation is a phenomenon arising from linear filtering rather than from a nonlinear source.


2019 ◽  
Author(s):  
Christopher Bergevin ◽  
Chandan Narayan ◽  
Joy Williams ◽  
Natasha Mhatre ◽  
Jennifer Steeves ◽  
...  

AbstractKhoomei is a unique singing style originating from the Central Asian republic of Tuva. Singers produce two pitches simultaneously: a booming low-frequency rumble alongside a hovering high-pitched whistle-like tone. The biomechanics of this biphonation are not well-understood. Here, we use sound analysis, dynamic magnetic resonance imaging, and vocal tract modeling to demonstrate how biphonation is achieved by modulating vocal tract morphology. Tuvan singers show remarkable control in shaping their vocal tract to narrowly focus the harmonics (or overtones) emanating from their vocal cords. The biphonic sound is a combination of the fundamental pitch and a focused filter state, which is at the higher pitch (1-2 kHz) and formed by merging two formants, thereby greatly enhancing sound-production in a very narrow frequency range. Most importantly, we demonstrate that this biphonation is a phenomenon arising from linear filtering rather than a nonlinear source.


2005 ◽  
Vol 83 (7) ◽  
pp. 721-737
Author(s):  
H Teffahi ◽  
B Guerin ◽  
A Djeradi

Knowledge of vocal tract area functions is important for the understanding of phenomena occurring during speech production. We present here a new measurement method based on the external excitation of the vocal tract with a known pseudo-random sequence, where the area function is obtained by a linear prediction analysis applied to the cross-correlation between the sequence and the signal measured at the lips. The advantages of this method over methods based on sweep-tones or white noise excitation are (1) a much shorter measurement time (about 100 ms) and (2) the possibility of speech sound production during the measurement. This method has been checked against classical methods through systematic comparisons on a small corpus of vowels. Moreover, it has been verified that simultaneous speech sound production does not perturb significantly the measurements. This method should thus be a very helpful tool for the investigation of the acoustic properties of the vocal tract in various cases for vowels.


2019 ◽  
Author(s):  
Alan Taitz ◽  
Diego E Shalom ◽  
Marcos A Trevisan

Silent reading is a cognitive operation that produces verbal content with no vocal output. One relevant question is the extent to which this verbal content is processed as overt speech in the brain. To address this, we investigated the signatures of articulatory processing during reading. We acquired sound, eye trajectories and vocal gestures during the reading of consonant-consonant-vowel (CCV) pseudowords. We found that the duration of the first fixations on the CCVs during silent reading are correlated to the duration of the transitions between consonants when the CCVs are actually uttered. An articulatory model of the vocal system was implemented to show that consonantal transitions measure the articulatory effort required to produce the CCVs. These results demonstrate that silent reading is modulated by slight articulatory features such as the laryngeal abduction needed to devoice a single consonant or the reshaping of the vocal tract between successive consonants.


Author(s):  
Andrzej Stefanski ◽  
Jerzy Wojewoda ◽  
Tomasz Kapitaniak ◽  
John Brindley

Abstract Properties of chaos synchronization have been used for estimation of the largest Lyapunov exponent of a discontinuous mechanical system. A method for such estimation is proposed and an example is shown, based on coupling of two identical systems with dry friction which is modelled according to the Popp-Stelter formula.


Sign in / Sign up

Export Citation Format

Share Document