From GammaSquad:

I would have gladly rallied first for some kind of “Happy Ending” bot to be invented, but one can’t complain too loudly when witnessing what the UK’s Bristol Robotics Lab has been up to recently. BRL’s director, Chris Melhuish, along with Loannis Leropoulos and other researchers, have proudly taken a giant step forward on the trail to building completely self-sustaining robots. The team has created a synthetic gut which allows their quaint EcoBot III to consume nutrients and then, every 24 hours, crap out the excess waste. My kind of robot.

At the start of the digestive process the robot feeds itself by moving into contact with a dispenser. This pumps a nutrient-rich solution of partially processed sewage into its “mouth” where it is distributed into 48 separate MFCs [microbial fuel cells -Ed.] within the robot. This fluid is a concoction of minerals, salts, yeast extracts and other nutrients. As unappetising as this mixture sounds, for the culture of microbes in the robot’s stomach it is ambrosia itself.

“Diarrhoea-bot would be more appropriate,” Melhuish admits. “It’s not exactly knocking out rabbit pellets.” Even so, he says, it marks the first demonstration of a biomass-powered robot that can operate unaided for some time. [Newsscientist]

While the concept of robots who consume their own energy source isn’t exactly new, up until now no other researchers have addressed the issue of the waste that is produced during the consumption process. EcoBot III has already impressed studies by surviving for up to seven whole days on its own, feeding and watering itself periodically.