Imagine a microscopic robot propelled by undulating hairs moving through your stomach to deliver medication to diseased cells. That's the kind of future researchers at ETH Zurich hope to manifest with their latest creation.
The team of scientists at the public research university in Switzerland has built a microrobot that's inspired by the movement of starfish larva. Their yet-to-be-named robot measures just a quarter of a millimeter across and swims through liquid by moving tiny surface hairs, or cilia, found on all kinds of microorganisms, including newborn starfish.
Like the sea creatures its movement is modeled after, the tiny robot is lined with ciliary bands, attached to the robot's body at a slope. Using an external source of ultrasound waves, the scientists are able to make the synthetic cilia oscillate 10,000 times per second, or about a thousand times faster than the ones on a baby starfish.
The rapid beating of the cilia creates a minuscule vortex in front of and behind the robot. This vortex zooms the tiny robot forward using a suction effect in front, with a thrust in the rear.
The research was led by Daniel Ahmed, a professor of acoustic robotics for life sciences and healthcare.
"In the beginning we simply wanted to test whether we could create vortices similar to those of the starfish larva with rows of cilia inclined toward or away from each other," Ahmed said in a statement.
The technology could be ideal for delivering life-saving drugs to hard-to-reach places inside the human body, and Ahmed believes the bot could have real medical applications in the foreseeable future.
"Our vision is to use ultrasound for propulsion, imaging and drug delivery," Ahmed said.
Steering the robot inside the human body, however, will require sharp imaging in real time. This will provide the next big challenge for the team. Ahmed anticipates the design of the robot could even have uses outside of medicine, such as moving around tiny amounts of liquid for other research, as well as industrial opportunities.