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Robot Locusts Harness the Power of Biology and Mechanics

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Locusts that have been bred for research are seen at a laboratory in the Department of Zoology at Tel Aviv University's Faculty of Life Sciences on December 22, 2015. Researchers have developed a high-jumping locust lookalike robot that they hope could one day replace humans in military or search-and-rescue operations. Nir Elias/Reuters

For most humans, insects are at best a nuisance and at worst targets to squash underfoot (or, increasingly, menu items to devour as delicacies). But Amir Ayali has spent years researching their nervous systems, behaviors and locomotion. The department of zoology professor at Tel Aviv University studies how they walk, jump and fly—all the kinds of movement he says at which they excel. Over the past few years, he’s been translating his observations so engineers can build better robots and other machines.

He’s examined the caterpillar’s crawling mechanism as inspiration for the emerging field of soft robotics and looked to the cockroach as a kind of “walking machine” that could help make more efficient robots with the utmost control over their legs. Ayali says biology can help lead to “energy-efficient green solutions that have been tested over several million years by evolution.”

Recently, the leaping prowess of the locust has captured Ayali’s attention as he works on an interdisciplinary team with his Tel Aviv colleague in the school of mechanical engineering, Gabor Kosa, and Uri Ben-Hanan in the mechanical engineering department at Ort Braude College. The team’s prototype is a remote-controlled robot that weighs less than an ounce and is only about 5 inches long but can jump 11 feet high and end up 4.5 feet away from its starting point, higher and farther than a locust. The body is 3-D-printed using the same plastic used to make Legos, and it holds a small battery. Its legs are stiff carbon rods with steel wire springs connecting them. Instead of relying solely on muscle or motor force, the locust and the miniature robot it inspired both store mechanical energy to power a jump. The locust bends its legs, locks the joint and stores energy in a stiff spring-like structure called the SLP (semi-lunar process), which helps propel the locust into the air upon release. The torsion springs fulfill a similar function in the robot version, which Ayali says can jump more than twice as high as similar-sized robots. A second prototype adds thin nylon wings that unfold at the peak of the jump to help the robot gain distance, by gliding, and make for a smoother landing. Although it obtains less height, it can travel about 12 feet. Future iterations could hone control over the robot’s movement and direction and might incorporate a flapping motion for the wings.

By swapping the remote control for autonomy, adding GPS or making other tweaks to the early prototypes, robot locusts could provide data from places where humans can’t fit, aren’t safe or want to avoid detection. “One hundred of these could cover efficiently very huge areas in search-and-rescue missions,” or on the site of a radioactive spill, Ayali says. “I leave it to anyone’s imagination what could be done with such a device in the battlefield or anywhere else.”

“If there were miniature robot Olympics, ours would win a gold medal,” he says.