Vocal exercise support systems

When the interaction between the vocal fold vibration and the vocal tract resonance increases during an exercise and the trainee achieves effective phonation, she or he feels strong vibrations around the lips. This feeling is thus used as a target of the exercise. We developed Smart Tube, a simple and low-cost system that provides biofeedback on the amplitude and frequency of the vibrations on the wall of the tube which are caused by the phonation.

Smart Tube is controlled through a small and inexpensive microcontroller board, Arduino Uno, which makes it handy and cost-effective. This system measures the vibration of the wall by an acceleration pickup and provides feedback through the number of lit LEDs and their color in real-time as shown in the following figure.

In tube phonation, a trainee must maintain phonations through a tube or straw for repeated intervals lasting between 5-10 s. It is usually recommended that there be 50 exercise phonations per day for one month (a total of 1,500 exercises); however, it is difficult to keep the trainee motivated during this period. So, we developed a biofeedback system, Straw fighter, based on a gamification framework and incorporates enjoyment and addictiveness of games into daily vocal exercises.

Straw fighter supports vocal (re)habilitation through a shooting game as shown in the following photo in which a user hits the enemy by phonating into a straw. It was implemented using an M5Stack Basic, which makes it convenient and cost-effective. It uses a plastic straw and the vibration of the straw is measured by an on-board acceleration sensor attached to the straw.