A continuous speech dialog system for the oral control of a sonar console

We present in this paper an application of a continuous speech understanding system to the control of a sonar console by a human operator. This application is really useful since it does correspond to a practical need of the operator who has his eyes busy looking at the sonar screen. It presents three original features: - the acoustic-phonetic decoding part of the system is not based on a classical phoneme labeling process but it yields for each segment of speech a set of acoustic phonetic labels that describe this segment very precisely. This phonetic labeling is associated with a special procedure for lexical access; - the system is actually a man-machine dialog system and not only a system capable of understanding a single sentence as it is often the case. The history of the dialog is used as a special knowledge source during the understanding process. This point highly increases the overall performance of the system; - the understanding process, and particularly the emission of hypotheses, is based on the knowledge about the language (lexicon and syntax) but also on the context of the dialog ; pragmatic knowledge is thus intimately associated with the analysis of a sentence. The paper presents the architecture of the system and its various components. It also discusses experimental results obtained in a multispeaker mode.