The strength of this new system lies in a machine learning algorithm that researchers have been working on for several years. This algorithm can (within limits) process articulatory movements that users cannot achieve when they start to use the system. This property is indispensable for the targeted therapeutic applications. The algorithm exploits a probabilistic model based on a large articulatory database acquired from an "expert" speaker capable of pronouncing all of the sounds in one or more languages. This model is automatically adapted to the morphology of each new user, over the course of a short system calibration phase, during which the patient must pronounce a few phrases.