March 28, 2022 -- When doctors can't easily reach someone -- whether it's in a war zone or a natural disaster -- robot bugs are being designed to come to the rescue.
That's because the same things that make some insects such invasive pests -- like their tiny size and resistance to harsh environments -- may make them ideal medical providers when doctors can't easily get to patients.
Engineers have built prototype robotic bugs designed to mimic insect movements so they can get into tight spaces and survive where living creatures might not. These creepy-crawlies were built using artificial muscle technology, a process that allows the robots to flex, bend, and move by jumping across surfaces the way many insects do.
"It's akin to loading an arrow into a bow and shooting it -- the robots latch on to build up energy and then release it in an impulsive burst to spring forward," says Ravi Shankar, PhD, a professor of industrial engineering at the University of Pittsburgh whose lab led the research.
What the engineering team came up with is a curved shape that allows the bugs to store energy to fuel rapid movements. This allows the robots to function with only a few volts of electricity.
The team published results from early tests of their prototype robotic bugs in the journalAdvanced Materials Technologies. At this stage, their main success is that they've worked out a way for the cricket-size robots to move with speed and precision using artificial muscle, a technology that typically moves more like a tortoise than a hare.
Versatile movements and a lightweight structure should let these robots travel a wide range of terrain, whether it's shifting sand dunes, rocky cliffs, or choppy waters, the engineers say.
In a disaster relief scenario, these robots could be deployed to find injured people in hard-to-access places, draw blood, take temperatures, or do other basic assessments, Shankar says. And they might be able to bring in miniature medical equipment to provide emergency first aid in the field.
Engineers are working on making the microbots even smaller so they can be more agile and enter difficult terrain.
"The opportunities multiply if we can develop smaller versions of these bugs or utilize swarms of such bots," Shankar says. "The underlying mechanisms we studied here can be miniaturized by at least another order of magnitude."
Think microscopic robot bugs moving inside blood vessels. They might be able to help with surgery, Shankar says, or form muscle tissue that's compatible with the human body to help treat or repair injuries.
"Once, we reach the millimeter or the sub-millimeter scale, unusual opportunities emerge for actuation and manipulation within the human body," he says.
For now, this is simply speculation, based on a promising prototype that moves well in a lab. But, Shankar says, "Some of these ideas are what motivate us to press on."