3D Palatography

International audienceIntroduction: Palatography has been widely used to investigate consonants articulation. This technique has however some drawbacks since its records the linguo-palatal contact pattern and most often does not take into account the shape of the palatal vault.This makes difficult to compare palatographic patterns across speakers.To alleviate this limitation, we propose a method to obtain a more realistic information about the articulation which copes with individual morphological differences. From a metrologic study based on plaster casts and a number of articulatory “prints”, we develop a method to obtain a 3D representation..Method: The method we propose to measure the shape of the palate, is based on the projection of a structured light (a grid) onto the palate. We observe that the projected grid is distorded as a function of the palatal shape. As the palate is not flat, columns and rows of the grid are modified and are not straight lines anymore. Taking into account these distortions permits the computation of the palate shape.This morphological information gained by this method can be used in static as well as in electyropalatography. Results: This method has been tested on known shapes, and is presently tested on artificial palates.Conclusions: This method could initiate new studies, by enabling measurements such as the surface, the position, the symmetry of the linguo-palatal contact and would improve intra and inter speakers comparisons. References: [1]A. MARCHAL. La palatographie, Paris: Editions du CNRS ( Collection Sons et Paroles), p 31, 1988. [2]Y.I KUZMIN. « Mobile palatography as a toll for acoustic study of speech sound ». Proc. 4th International Congress Acoustic. Compenhagen: 1-3. [3]W.K KYDD & D.A BELT« Continuous Palatography». Journal of speech and Hearing Research, 29:489-494. [4]G. WITTING. « New techniques of palatography». Studia Lignuistica, 7:54-68.R