Things that scurry are hard to predict. They're nervous and quick — and no one likes a small, nervous, quick thing. But one robot seems to be going against the grain. It's a cockroach-inspired machine, and it might give you nightmares.
Before it was round, the cuboid robot just got stuck
When I think of robots, I don't think machines that "scurry." Mice scurry. Cockroaches scurry. Robots? They jump over things like weird-looking leopards or fall over themselves like the lumbering chunks of metal they are. They certainly do not scurry. That said, this thing is cool. No matter how weird it is to watch it move around like something I'd be tempted to crush with a shoe, the fact that this tiny robot is both fast and nimble is kind of amazing. But what's even more interesting is the reason for its agility. Because, as it turns out, that's largely a function of its shape.
The first robot designed by this team of engineers was shaped like a cube, says Chen Li, a mechanical engineer at the University of California-Berkeley and a co-author of the Bioinspiration & Biomimetics study that describes the machine. "This made the robot turn left or right when it touched obstacles and become stuck." But a thin, rounded exoskeletal shell — the current design — lets the robot roll and fit its thin body through small gaps, just like a cockroach. And the researchers are certain that shape is the only variable responsible for this robot's newfound agility. The control program stayed the same, "so we know that it was only the shell shape that enabled its traversal," Li says.
Credit: Chen Li. Courtesy of PolyPEDAL Lab, Biomimetic Millisystems Lab, and CiBER, UC Berkeley
Most robots try to avoid obstacles
This might come as a surprise, but a tiny robot that can navigate rough terrain and tiny gaps without the use of sensors is pretty innovative. Most robots deal with obstacles by avoiding them. They use maps, path planning and feedback control to go around objects that stand in their way. And that approach has worked out really well, for the most part. But when you're working with a tiny robot — one that's about 7 inches long — working with large, heavy, expensive sensors is a huge hassle. So the fact that changing this robot's outer shell had such a big impact could open up a ton of possibilities for the robotics industry. Rounded shells could be used to build small, inexpensive robots for search and rescue missions or precision agriculture, Li ventures.
Building this robot took two years. During that time, the scientists spent a lot of time observing insects move through laser cut paper "beams" intended to act like grass. "The goal was to understand how small animals traverse dense obstacles," Li says.
Good for small search and rescue robots
Mimicking the forms we see in nature isn't a new design technique; nature's chaos is a far better engineer than humans will ever be. Still, a cockroach-inspired robot can be unsettling. So I've come up with a way to make it a bit more palatable. Instead of imaging it running up your bedroom walls, think of the robot as some sort of friendly Wall-E, pet-cockroach hybrid.
Cartoons just make everything better, don't they?