MODÉLISATION ARTICULATOIRE DU CONDUIT VOCAL

Abstract
Recently, there is see renewed interest in the representation of speech at the articulatory level. For such a representation, it is essential to have a parsimonious model which is capable of describing accurately and meaningfully the states of the vocal tract during speech production. In this paper, first we briefly review various types of models proposed in the past. Then we focus our attention to a specific type of articulatory models, which are derived from a factor analysis of sagittal X-ray film data. The advantage of this type of model is that the vocal tract profiles are specified by a small number of the model parameters, less than 10, and their values can be directly calculated, not estimated, from data. Second, we describe the particular relationships between the model parameters and acoustics parameters (formant frequencies) that suggest acoustic compensation between different articulators as the lower jaw and tongue-body. Our analysis of X-ray data shows that such compensation is actually used in speech production, and that the larger variability in articulatory "targets" than in acoustic ones is, in part, due to compensation.