  The Intelligent Voice Prosthesis is a communication tool which reconstructs
the meaning of an ill-structured sequence of icons or symbols, and expresses
this meaning into sentences of a Natural Language (French). It has been
developed for the use of people who cannot express themselves orally in natural
language, and further, who are not able to comply to grammatical rules such as
those of natural language. We describe how available corpora of iconic
communication by children with Cerebral Palsy has led us to implement a simple
and relevant semantic description of the symbol lexicon. We then show how a
unification-based, bottom-up semantic analysis allows the system to uncover the
meaning of the user's utterances by computing proper dependencies between the
symbols. The result of the analysis is then passed to a lexicalization module
which chooses the right words of natural language to use, and builds a
linguistic semantic network. This semantic network is then generated into
French sentences via hierarchization into trees, using a lexicalized Tree
Adjoining Grammar. Finally we describe the modular, customizable interface
which has been developed for this system.
