Industrial robots could ‘eat metal’ to power themselves

A fundamental manufacturing shift is on the horizon, some say. It’s where robots run all elements of our future factories. The machines will operate using brain-copying artificial intelligence and handle not only manufacturing processes, but also supply-chain logistics, planning, and other roles formerly performed by humans.

This vision of the future anticipates an industrial workplace where Internet-connected machines will mimic humans, yet do the jobs more precisely, faster and cheaper than humans.

And the human-copying element may not end there. Researchers at the University of Pennsylvania are suggesting that robots could end up eating like humans, too.

Robots will “eat metal for energy,” according to a news article published in Medium. The researchers’ vision for a “metal-air scavenger” could solve one of the quandaries of future IoT-enabled factories. That quandary is how to power a device that moves without adding mass and weight, as one does by adding bulky batteries.

The answer, according to the University of Pennsylvania researchers, is to try to electromechanically forage for energy from the metal surfaces that a robot or IoT device traverses, thus converting material garnered, using a chemical reaction, into power.

“Robots and electronics [would] extract energy from large volumes of energy dense material without having to carry the material on-board,” the researchers say in a paper they’ve published in ACS Energy Letters.

It would be like “eating metal, breaking down its chemical bonds for energy like humans do with food.” Batteries work by repeatedly breaking and creating chemical bonds.

The research references the dichotomy between computing and power storage. Computing is well suited to miniaturization, and processers have been progressively reduced in size while performance has increased, but battery storage hasn’t. You need a bigger battery for more energy.

Even if swarming, industrial robots became the size of insects (I’ve written about the possibility), there’s an issue powering the nano devices – the required size of the power source would defeat the object of the miniaturization. The battery alone could crush the device, and even if it didn’t, the machine would need excessive amounts of energy to move, because of the battery mass. This conundrum is one of the reasons there’s an emphasis in IoT development to find ways to harvest energy ambiently.

However, with ambient power – such as is found in solar or potentially magnetism, for example – power density comes into play. That’s where the harvesting technology can’t pull enough energy out of the environment, or it does it so slowly that it’s not as power-effective as traditional batteries.

Enter the metal-eating robot. The University of Pennsylvania researchers’ form of harvesting efficiently replicates a power-dense battery. Metal is more dense than the battery chemistry.

The group performs their foraging energy production with a hydrogel electrolyte sponge towed by the robot. It uses a cathode, dragged over the surface, to extract amperages from the metal fuel source, such as steel or aluminum.

“Our [metal-air scavenger] has a power density that’s ten times better than the best harvesters, to the point that we can compete against batteries,” said James Pikul, an assistant professor in the University of Pennsylvania’s Department of Mechanical Engineering and Applied Mechanics and one of the paper authors, in the Medium post. “It’s using battery chemistry, but doesn’t have the associated weight, because it’s taking those chemicals from the environment.”

This method is also potentially better than existing lithium-ion battery chemistry, according to Pikul.

“One day, a robot that needs to recharge its batteries will just need to find some aluminum to ‘eat,'” Pikul said.

The robot, although ultimately likely to be a better worker than the human, is a messy eater. As it oxidizes the metal it passes over, it leaves a “microscopic layer of rust in its wake,” according to the article.