June 24, 2005

Ann Sullivan
NASA Ames Research Center, Moffett Field, Calif.
Phone: 650/604-3039 or 650/604-9000
E-mail: Ann.Sullivan@nasa.gov

Bill McKee
Xerox Corporation, Rochester, N.Y.
Phone: 585/423-4476
E-mail: bill.mckee@usa.xerox.com

RELEASE: 05_38AR

NASA, XEROX TO DEMONSTRATE 'VIRTUAL CREW ASSISTANT'

Intelligent conversation with robots - long the bread and butter of 
science fiction authors - soon may take another step closer to 
reality for astronauts on the International Space Station 
(ISS).</br></br> Scientists from NASA Ames Research Center in 
California's Silicon Valley and Xerox Corporation, Rochester, NY, 
will demonstrate the sophisticated, voice-operated computer system on 
June 26 at the Association for Computational Linguists' 25th annual 
meeting at the University of Michigan, Ann Arbor. Called Clarissa, 
the system was developed in an effort to ease astronaut workload. 
</br></br> "Clarissa is a fully voice-operated 'virtual crew 
assistant,' enabling astronauts to be more efficient with their hands 
and eyes and to give full attention to the task while they navigate 
through the procedure using spoken commands," said Beth Ann Hockey, 
project lead on the team that developed Clarissa at NASA Ames. Plans 
call for ISS astronaut John Phillips to complete the Clarissa 
training procedure onboard the ISS as early as June 27 in preparation 
for later use of Clarissa. "This will be the first use of the system 
in space," Hockey said.</br></br> Clarissa is 'hands-free' and 
responds to astronauts' voice commands, reading procedure steps out 
loud as they work, helping keep track of which steps have been 
completed, and supporting flexible, voice-activated alarms and 
timers. Astronauts now perform about 12,000 complex procedures to 
maintain life-support systems, inspect space suits, conduct science 
experiments, perform medical exams and other routine tasks.</br></br> 
"Just try to analyze a water sample while scrolling through pages of 
a procedure manual displayed on a computer monitor while you and the 
computer float in microgravity," challenges astronaut Michael Fincke, 
who recently completed a six-month stay on the space station. "To be 
able to speak to the system and hear the step-by-step instructions 
while my hands are free to complete the procedure would be like 
having another crew member aboard."</br></br> Because the system is 
required to always be ready to accept a voice command, the original 
version tried to process all spoken words, including conversations 
between crew members. As a result, Clarissa had difficulty discerning 
between conversations and commands given to the system.</br></br> In 
2004, Clarissa lead implementer Manny Rayner of NASA Ames contacted 
Xerox researcher Jean-Michel Renders of Xerox Research Centre Europe 
about a possible collaboration. They hoped that Xerox's experience in 
machine learning, linguistics and text categorization would increase 
the system's accuracy on the 'open microphone' task.</br></br> "NASA 
wanted the system to be ready to assist at any time and without 
requiring artificial activation commands," said Renders. "Therefore, 
a simpler 'Star Trek' solution -- like having crew members address 
the computer by stating a specific word such as 'computer' before 
posing a question or speaking a command to the system -- wasn't a 
viable solution. We needed to improve the performance of the system 
in discriminating between commands and conversation."</br></br> The 
Xerox methodology allows Clarissa to more accurately analyze each 
utterance. It can recognize words, sentences and word context, and 
act on a variety of commands phrased in different ways. The system 
now looks at all the individual words within the sentence, takes into 
account the system's confidence that it has correctly recognized each 
individual word, and uses a sophisticated machine-learning algorithm 
to weigh the various pieces of positive and negative information. 
This significantly increases the system's ability to determine the 
difference between commands directed to the system and side 
conversations. The new improvements have boosted the success rate for 
correctly identifying system commands to 95 percent. </br></br> 
Clarissa currently supports about 75 individual commands, which can 
be accessed using a vocabulary of some 260 words. The team plans to 
increase the commands and add to the vocabulary in the future. "Some 
commands are rather simple, but others are quite complex," Hockey 
said. "A lot of the time, you're just saying 'next' or 'go to step 
eight'. But you also might need to say something like 'cancel the 
alarm at 10:25' or 'set challenge verify mode on steps three through 
fourteen." </br></br> "Working with Xerox on Clarissa shows the many 
benefits of forming collaborative partnerships between research 
organizations," said Hockey. "We are excited about the results." 
</br></br> For more information about the Clarissa project, go to: 
</br></br> 

http://tc.arc.nasa.gov/projects/clarissa/

</br></br> Images illustrating the Clarissa project can be found at: 
</br></br> 

http://www.nasa.gov/centers/ames/multimedia/images/2005/Clarissa.html

	
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