For those who are into popular culture, nanobots are a familiar concept. Tiny robots that can move around unnoticed, even inside the human body, and perform remarkable tasks.
On May 25, engineers at Northwestern University in Chicago posted a paper on their flea-sized robots. Although they've created robots that look like inchworms, crickets, and beetles, it's the ones that look like crabs that are getting the most attention.
While not actually nano-sized, they're the smallest remote-controlled robots ever made, measuring a tiny half-millimeter. The minuscule machine can move at a speed of half its own width per second.
Instead of moving thanks to complex hydraulics or electric motors controlled by computers, as depicted in science-fiction, these robots move thanks to shape-memory alloys. Essentially, this means that they've "trained" material to remember two shapes, one for when it's cold and one for when it's warm. The robots' limbs are heated using a scanned laser beam and then quickly cool down due to the robot's small size. In fact, further reducing the size should increase the robot's speed.
While the achievement is remarkable in and of itself, it's the potential application in the real world that's most intriguing.
“You might imagine micro-robots as agents to repair or assemble small structures or machines in industry or as surgical assistants to clear clogged arteries, to stop internal bleeding or to eliminate cancerous tumors — all in minimally invasive procedures”, says John A. Rogers, who led the experimental work.
Image: Northwestern University