A British-built robot generates its own power by gobbling flies, but it has a stinky downside — it needs human sewage as bait to catch the insects and then digest them.
EcoBot II, made by robotics experts at the University of the West of England in Bristol, tucks into the flies in eight microbial fuel cells which are loaded with human sewage.
Bacteria in the sewage munch on the soft tissues of flies, releasing enzymes that break down the hardened shell, made from a sugary substance called chitin, which comprises the insects’ hard exterior, the exoskeleton.
Sugar molecules released from the degraded chitin are then absorbed and used as energy by the bacteria, which in so doing release electrons that are harnessed to generate current, the British weekly New Scientist reports in next Saturday’s issue.
The point behind the experiment is, ultimately, to create ”release and forget” roving droids that are almost completely autonomous. They could be sent into dangerous or inhospitable areas, which points to a wide range of military, security or industrial uses.
EcoBot II is a long way from that.
It takes 12 minutes to muster up enough energy to take a tiny step forward and radio its position back to base — a top speed of just 10cm per hour.
But it is very energy efficient, travelling around for five whole days on just eight fat flies, one in each fuel cell.
So far, the researchers are manually feeding EcoBot with dead bluebottles. They are working on the next step, which is to make the droid predatory, using the sewage as bait to catch the flies.
Researchers in Florida are also working on a robot — a train-like device called Chew Chew — that uses microbial fuel cells for its power, New Scientist says.
But in Chew Chew’s case, the bacteria feed on sugar cubes.
Ecobot’s advantage is that it can use unrefined fuel from sources in the wild. – Sapa-AFP