In October of this year, we reported on a raven that had some serious issues with a coffee drone entering its airspace. It brought up an important question: Who will own the future (low altitude) skies, birds or drones? Now, player three has entered the game! A bird robot with falcon-like legs that allows it to land on perches perfectly.
William Roderick, a recently graduated Stanford University Ph.D. student, led the bird-bot construction effort. The final product took Roderick and his colleagues years to create as a part of a National Science Foundation Fellowship in perching aerial robots.
In the video above, Roderick shows off the bird-like drone robot, “stereotyped nature-inspired aerial grasper,” or SNAG. The mechanical engineer notes that the almighty peregrine falcon— a cosmopolitan bird of prey—inspired the bot’s legs. Something the real bird was able to do by serving as a subject for inspection with five high-speed cameras.
![A perching bird-like robot with its legs outstretched, preparing to land on a branch in a forest.](https://legendary-digital-network-assets.s3.amazonaws.com/wp-content/uploads/2021/12/12194058/Perching-Bird-Bot-feature-image-12082021.jpg)
“It’s not easy to mimic how birds fly and perch,” Roderick said in a Stanford press release. “After millions of years of evolution, they make takeoff and landing look so easy, even among all of the complexity and variability of the tree branches you would find in a forest.”
SNAG has two legs, each of which can move independently. Its rigid legs, along with its foot structures, act like “bones” for the robot. And its motors, like muscles. Roderick notes that SNAG’s legs work by first absorbing the kinetic energy created by landing on a surface. The robot then grasps its perch with claws in a way that mimics peregrine falcons. (The real birds use a formulaic approach, no matter what type of surface they land on.) Then, once the bird-bot has grasped its perch, it uses a balancing algorithm to stabilize itself.
![A peregrine falcon with its wings spread, landing on a branch.](https://legendary-digital-network-assets.s3.amazonaws.com/wp-content/uploads/2021/12/12194037/Bird-bot-body-image-1.png)
As for use cases, Roderick says the legs could help drones safely land after flights. Especially in woodier parts of the world with more dynamic terrains. “Part of the underlying motivation of this work was to create tools that we can use to study the natural world,” Roderick added in the press release. “If we could have a robot that could act like a bird, that could unlock completely new ways of studying the environment.”