New Robot Eats Metal for Fuel
Photo Credit: MTGR - robo-team.com
Fuel for small tech has always been an issue, limiting scale of small robots. Some have utilized solar power, some have utilized electric and gas fuel, and now some will be using metal. Engineering professor James Pikul recalls,
"This inverted relationship between computing performance and energy storage makes it very difficult for small-scale devices and robots to operate for long periods of time...There are robots the size of insects, but they can only operate for a minute before their battery runs out of energy."
Pikul's team at the University of Pennsylvania have found that they can power machines from the energy in oxidation. By simply breaking chemical bonds on the surfaces of metal, it re-forms new bonds that can propel the device forward. This process is very effective, resulting in a power density 10x bigger than the most efficient harvesters on the market, and a density 13x bigger than lithium-ion batteries.
The power device consists of a cathode (a junction that transfers electric current) connected to a layer of polymer chains called a "hydrogel" which create electrons when they drag over surfaces. When it touches metal, the metal reacts as an anode producing a current that can be harvested. The result leaves an oxidized metal surface with immediate microscopic rust. This is the same science used within a battery, except only half of the battery is constructed - the other half can be any metal the robot comes in contact with.
This new technology could change the way robots are designed. It could allow many to travel much longer distances than previously anticipated.
"As we get robots that are more intelligent and more capable, we no longer have to restrict ourselves to plugging them into a wall. They can now find energy sources for themselves, just like humans do."