This soft robotic stingray is made of rat heart muscle. Yeah, it’s just as crazy as it sounds.
“Roughly speaking, we made this thing with a pinch of rat cardiac cells, a pinch of breast implant, and a pinch of gold. That pretty much sums it up, except for the genetic engineering,” says Kit Parker, the bio-engineer at Harvard who led the team that developed the strange robot.
“I THINK WE’VE GOT A BIOLOGICAL LIFE-FORM HERE.”
Parker’s robotic stingray is tiny—a bit more than half an inch long—and weighs only 10 grams. But it glides through liquid with the very same undulating motion used by fish like real stingrays and skates. The robot is powered by the contraction of 200,000 genetically engineered rat heart-muscle cells grown on the underside of the bot. Even stranger, Parker’s team developed the robot to follow bright pulses of light, allowing it to smoothly twist and turn through obstacle courses. The fascinating robot was unveiled today in the journal Science.
“By using living cells they were able to build this robot in a way that you just couldn’t replicate with any other material,” says Adam Feinberg, a roboticist at Carnegie Mellon University who has worked with Parker’s team before, but was not involved in developing this new robot. “You shine a light, and it triggers the muscles to swim. You couldn’t replicate this movement with on-board electronics and actuators while keeping it lightweight and maneuverable. And it really is remote controlled, like a TV set.”
HOW TO BUILD A LIVING BOT
To understand just how muscles from a rat can power a robot stingray, let’s dissect this bad boy layer by layer. The stingray bot is composed of four sequential layers of material. The top layer is a 3D body of a silicone material—”the same thing as the outer coating of a breast implant,” says Parker—that’s been cast in a titanium mold. This flexible, bendy body holds the other materials together.