Page 35 of NASA mentions CHEW CHEW robot..Here is an article about it.

Meat-eating robot has (g)astronomic potential

July 21, 2000 
Web posted at: 3:28 PM EDT (1928 GMT) 
LONDON (Reuters) -- Man really is in danger of being swallowed up by technology after U.S. scientists announced on Wednesday they had designed a robot that runs on meat.
Dubbed Chew Chew the "gastrobot," a 12-wheeled train-like robot runs on a microbial fuel cell, which breaks down food with bacteria and converts it into electrical energy, according to a report in New Scientist magazine.
The cell works by producing enzymes that break down carbohydrates, releasing energy, inventor Stuart Wilkinson of the University of South Florida in Tampa told the magazine.
"The ideal fuel in terms of energy gain, is meat. Vegetation is not nearly as nutritious," Wilkinson said. "Changing food into electricity isn't unique. What I've done is to make it small enough to fit in a robot.
Chew Chew eats sugar cubes but early applications for gastrobots may include lawnmowers which eat grass clippings, New Scientist said.
But Chew Chew's diet is refined compared to that of a gastrobot being developed at the University of the West of England -- it eats slugs.
Wilkinson is jokingly aware of the dangers of giving gastrobots a taste for meat: "Otherwise they'll notice there's an awful lot of humans running about and try to eat them."
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