But scientists say the lizards’ tails are just as extraordinary, with geckos performing a remarkable, if ungainly, maneuver that allows them to land securely and at ballistic speeds on vertical surfaces like tree trunks.
However, by capturing high-speed video of the Asian flat-tailed gecko and then building robot models of the lizards, to their surprise, the researchers found that the lizards crash headfirst at speeds of up to 21 kilometers per hour (13 miles per hour) and only stabilize on landing by using their tails to absorb the energy of impact.
To better understand the forces the lizard experiences while making the maneuver, the team built two gecko-inspired robots — one with a tail and one without.
They 3D-printed the robots from soft plastic and rubber-like materials and catapulted them at a force plate, a sensitive scale that measures the landing impact. Only the robot with the tail could stick to the plate, validating the researchers’ observation that the tail was essential to stabilizing the lizard after it collides with a trunk at high speed.
Jusufi said the findings could help make more sophisticated robots. “This offers an alternative strategy for flying robots to land on walls, and flying robots can be used for construction or maintenance or search and rescue.”
He said it was possible that other species of lizards were able to perform such a maneuver, but it hadn’t been documented in any other animal before.
“It’s unexpected, right? In some ways it was thought if you have such amazing feet with such a high safety factor then why would you need a back-up mechanism?”
“It turns out that nature has some very challenging surfaces for these geckos. They slip on moss, bark, sand and such debris that they flip a lot even with the world’s best feet.”