Real-time control of a 2D animation model of the vocal tract using optopalatography

This paper presents an animated 2D articulation model of the tongue and the lips for biofeedback applications. The model is controlled by real-time optopalatographic measurements of the positions of the upper lip and the tongue in the anterior oral cavity. The measurement system is an improvement on a previous prototype with increased spatial resolution and an enhanced close-range behavior. The posterior part of the tongue was added to the model by linear prediction. The prediction coefficients were determined and evaluated using a corpus of vocal tract traces of 25 sustained phonemes. The model represents the tongue motion and the lip opening physiologically plausible during articulation in real-time.