Mechanical model of vocalization created

Scientists have created a mechanical model of the process required for producing speech.

When people speak, sing, or shout, they produce sound by pushing air over their vocal folds -- bits of muscle and tissue that manipulate the air flow and vibrate within it.

When someone has polyps or some other problem with their vocal folds, the airflow can be altered, affecting the sound production.

"Voice disorders affect 30 percent of the general population and up to 60 percent of educators. The objective of our work is to develop a detailed understanding of the phonation process, which will enable the development of computational models," said George Washington University professor Michael Plesniak.

In order to better characterize the physics of this process, the researchers investigated the velocity field and flow structures in the airflow that occur when a person speaks.

They constructed a mechanical model of the vocal folds that had motorized, programmable components that can alter their shape and motion in various ways to mimic vocal folds.

By placing this model in a wind tunnel, they examined normal vocalization and common pathologies like the formation of polyps and cysts.

Plesniak said that an important feature of the model is that it is seven-and-a-half times larger than the actual physiology, which allows the dynamics to be studied in greater detail.

He added that the ultimate goal is to create tools to help surgeons make preoperative assessments of how a vocal tract surgery will affect an individual's voice.