Many researchers have seen in the articulation an intermediate level of representation. In the gestural phonetic theory, units are articulatory gestures. In order to assess this theory with observed parameters, we have defined a robust labelling system (AMULET) of the multi sensor ACCOR speech database. Main articulatory gestures searched are Voice Onset and Voice Termination on both acoustic and laryngographic signals. We present here two efficient Voiced/Unvoiced/Silence detectors for the acoustic signals and a third one for the laryngographic signal.