Some would argue that the biggest obstacle robotics currently faces isn't the Uncanny Valley or suppressing the urge to destroy all humans—it's keeping their batteries charged. The newest version of the EcoBot may have the answer—it eats poop. Our poop.
Powering robots is pretty straightforward—either have a whole bunch of spare AA's on hand or train it to plug into a wall socket like a Roomba. But if you're taking your robot on a trip to say, the ISS, neither of these options proves tenable. But what if the robot could power itself from fecal matter generated by the station's crew? Well, it could run indefinitely.
The EcoBot is an energetically autonomous robot that powers itself by consuming waste matter. The robot is now on its third iteration. The original ran on refined sugar with an E. coli engine and the second ran on shrimp husks and dead flies using a sludge microbe generator. However, neither of these designs were truly self-sufficient because they had no means of expelling waste—robopoop, if you will. But the EcoBot-III does, and that makes it the world's first fully energy-autonomous robot ever built. It's even housebroken. Instead of simply shitting willy-nilly all over the floor, it uses a litterbox. And here it is pooping:
The EcoBot-III can operate for up to seven days at a time, collecting fuel and water from the area, then running it through a series of 48 Microbial Fuel Cells, then expelling the waste at the end of the day. "Robots that eat biological fuels could find enough fuel almost anywhere," said John Greenman, a microbiologist at the Bristol Robotics Laboratory where the robots are being developed. "There is organic matter anywhere on Earth - leaves and soil in the forest, or even human waste such as urine and feces."
As for longevity, since the process doesn't involve mechanization, an EcoBot could theoretically run for years. "We know MFCs will last as long as they're fed; there's nothing mechanical to go wrong with them," Greenman told InnovationNewsDaily. "They could go 20 or 30 years. As long as the microbes grow, they can keep going." So, as long as there are humans around, the EcoBot will continue to live. That's certainly one way to keep HAL from murdering your crew. [Technabob - Geekosystem - Scientific American - Wikipedia]