Event

Spoken Dialogue Systems for Space and Lunar Exploration

Jim Hieronymus

NASA Ames Research Center, Mountain View, California

Tuesday, January 27, 2009
12:30

Building spoken dialogue systems for space applications requires systems which are flexible, portable to new applications, robust to noise and able to discriminate between speech intended for the system and conversations with other astronauts and systems. Our systems are built to be flexible by using general typed unification grammars for the language models which can be specialized using example data. These are designed so that most sensible ways of expressing a request are correctly recognized semantically. The language models are tuned with extensive user feedback and data if available. The International Space Station and the EVA Suits are noisy (76 and 70 dB SPL). This noise is best minimized by using active noise canceling microphones which permit accurate speech recognition. Finally open microphone speech recognition is important to hands free, always available operation. The EVITA system has been tested in prototype lunar space suits in the Arizona desert. Using an active noise canceling head mounted microphone in a pressurized suit, the lowest word error rate was 3.6 % for a 2500 word vocabulary. A short clip of the surface suit spoken dialogue system being used in a field test will be shown.