Advances in combined electro-optical palatography

This paper describes the development of a device that combines the electropalatographic measurement of tongue-palate contact with optical distance sensing to measure the mid-sagittal contour of the tongue and the position of the lips. The device consists of a thin acrylic pseudopalate that contains both contact sensors and optical reflective sensors. Application areas are, for example, experimental phonetics, speech therapy, and silent speech interfaces. With regard to the latter, the prototype of the system was applied to the recognition of vowels from the sensor signals. It was shown that a classifier using the combined input data from both the contact sensors and the optical sensors had a higher recognition rate than classifiers based on only one type of sensory input.