Cockroach inspires robot that can squeeze through cracks
09 February 2016
UC Berkeley biologists have found robotic inspiration in the ability of cockroaches to flatten themselves and squeeze through even the tiniest crack.
“What’s impressive about these cockroaches is that they can run as fast through a quarter-inch gap as a half-inch gap, by reorienting their legs completely out to the side,” says study leader Kaushik Jayaram (now at Harvard University). “They’re about half an inch tall when they run freely, but can squish their bodies to one-tenth of an inch.” Moreover, when they traverse crevices, they can withstand forces 900 times their body weight without injury.
Using the roach technique as inspiration, Jayaram designed a simple and cheap palm-sized robot that can splay its legs outward when squashed, then capped it with a plastic shield similar to the tough, smooth wings covering the back of a cockroach. The Compressible Robot with Articulated Mechanisms (CRAM) is able to squeeze into and run through crevices half its height.
Jayaram built the model robot using an origami-like manufacturing technique, now available as an inexpensive kit made by Dash Robotics — a commercial spin-off from previous robotic work at UC Berkeley. Now, more robust versions will be needed for real-world testing.
“This is only a prototype, but it shows the feasibility of a new direction using what we think are the most effective models for soft robots; that is, animals with exoskeletons,” says UC Berkeley's Professor Robert Full. “Insects are the most successful animals on earth. Because they intrude nearly everywhere, we should look to them for inspiration as to how to make a robot that can do the same.”
Full believes these robots could be used in search-and-rescue operations, squeezing their way through the rubble resulting from tornadoes, earthquakes and explosions.
Full and students in his Poly-PEDAL lab at UC Berkeley have engaged in long term studies of the ways animals walk, run, jump, glide, crawl and slither in order to understand the basic bio-mechanical principles that underlie locomotion, and that might also be used to design better robots.
YouTube video by Roxanne Makasdjian and Stephen McNally, with footage and photos by Tom Libby, Kaushik Jayaram and Pauline Jennings. Courtesy of PolyPEDAL Lab UC Berkeley.