Getting inspiration from a chameleon’s tongue, researchers have created soft robots that can recreate high-powered and high-speed motions using stored elastic energy.<\/p>\n
Chameleons, salamanders, and many toads use stored elastic energy to launch their sticky tongues at unsuspecting insects located up to one-and-a-half body lengths away, catching them within a tenth of a second.<\/p>\n
The researchers made the robots using stretchable polymers similar to rubber bands, with internal pneumatic channels that expand upon pressurization. To store the elastic energy, the robots stretch their body in one or multiple directions during the fabrication process following nature-inspired principles.<\/p>\n
Similar to the chameleon’s tongue strike, a pre-stressed pneumatic soft robot can expand five times its own length, catch a live fly beetle, and retrieve it in just 120 milliseconds.<\/p>\n
“We believed that if we could fabricate robots capable of performing such large-amplitude motions at high speed like chameleons, then many automated tasks<\/a> could be completed more accurately and in a much faster way,” says Ramses Martinez, an assistant professor in the School of Industrial Engineering and in the Weldon School of Biomedical Engineering at Purdue University.<\/p>\n “Conventional robots are usually built using hard and heavy components that slow down their motion due to inertia. We wanted to overcome that challenge.”<\/p>\n Many birds, like the three-toed woodpecker, achieve zero-power perching using the elastic energy stored in the stressed tendons at the back of their legs, allowing them to not fall off a perch when asleep.<\/p>\n The anatomy of these birds has served as an example to enable the fabrication of robotic grippers capable of zero power holding up to 100 times their weight and perching upside down from angles of up to 116 degrees.<\/p>\n This video shows how these bird-inspired soft robotic gripper catching a ball moving at 10 millimeters per second in only 65 milliseconds:<\/em><\/p>\nReacts in 50 milliseconds<\/h3>\n