The Technology Behind the Fly-Eating Robot
In our news article, “Some Robots Eat Dust – Others, Flies“, we featured a box-shaped robot that, well, processed dead flies and used the produced chemicals to fuel itself in order to hunt for more bugs. Perhaps you’d want to read more about a technology that makes this possible.
One of the major advantages of human beings over robots is our superior ability to adapt & find means to survive on our own. Most of today’s robots need a source of energy to drive them. Now, there’s a big difference between the Roomba’s auto docking feature and actually seeking out its own source of energy, whether there’s a dock available or not.
Introducing microbial fuel cells (MFC).
Just like all batteries, a fuel cell has two electrodes, a positive one and a negative one. For electricity to be produced, electric current or the flow of charged particles must exist. Thus, this fuel cell must also have an electrolyte which will take care of transporting the charged particles from one electrode to the other. It also needs a catalyst to split up the proton and electron (the charged particles that I mentioned) from a fuel source.
In this particular fuel cell, bacteria found in sludge serves as the catalyst. It separates the proton and the electron found in the fuel – the fly – in one electrode. The electron flows into the circuit while the proton (hydrogen) moves in the opposite direction. Both of them then move towards a compartment containing the other electrode. When they combine with O2 found in that compartment, water is produced.
The entire process continues to make a closed circuit.
The current technology still has some major limitations. One of them is the amount of energy produced – it cannot support large continuous movements. That is why in most cases, such as in the news article, only the conveyor-belt portion is the one moving; not the entire robot.
Nevertheless, MFC technology is a very promising one. Imagine an iRobot Dirt Dog capable not only of eating dust, but all the bugs in the house as well.
