With Falcon-Like Claws, This Aerial Drone Can Land, Grip and Perch on Branches

The quadrocopter was also able to catch objects tossed by researchers, such as bean bags and tennis balls

The quadrocopter dubbed “SNAG” has feet and legs modeled after a peregrine falcon William Roderick via Stanford University

A new drone is taking inspiration from nature’s best flyers: birds. The bio-inspired aerial bot, which was developed by Stanford engineers, combines four sets of propellers on top with a set of bird-like features below, such as grasping claws and bending legs that allow it to land smoothly almost anywhere.

“It’s not easy to mimic how birds fly and perch,” says Stanford mechanical engineer William Roderick, who co-authored the study, in a statement. “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.”

While flying robots can skillfully navigate the skies, they haven’t aced landing, per Matt Simon for Wired. The four-propeller drones called “quadrocopters” are likely to topple over on any uneven surface. By contrast, birds can perch on just about anything—despite the wide variety of sizes, shapes, and textures of tree branches.

“Everything is a landing strip for a bird,” says study co-author David Lentink, a biologist and roboticist at the University of Groningen in the Netherlands, to Wired. “To us, this is really inspiring: The whole idea that if you would just design different landing gear, you might be able to perch just anywhere.”

The research, which was published this week in Science Robotics, comes after years of studying the mechanics of bird perching and other animal-inspired flying robots. The final creation requires minimal computational power from its control board, which allows new features and equipment to be incorporated in future versions, reports Margo Milanowski for Popular Science. The development team dubbed the bird-inspired drone Stereotyped Nature-Inspired Aerial Grasper, or SNAG.

The one-and-a-half-pound quadrocopter, which has feet and legs modeled after a peregrine falcon, can catch and carry objects ten times its own weight. SNAG combines 3D-printed plastic “bones” with motors and fishing line that act like muscles and tendons.

Scientists tested SNAG’s performance in both a lab and in a forested environment, launching the bot at different tree branches. They found that the drone was able to catch objects tossed by researchers, such as a bean bag and tennis ball, reports George Dvorsky for Gizmodo. One of SNAG’s current limitations is that it isn’t autonomous: a pilot had to remote-control the robot. But Lentink, Roderick, and their colleagues are already working on a way for the robot to spot a branch, determine how to approach it, and execute the landing on its own.

The research team hopes the aerial bot could help gather information about wildlife, conduct search and rescue missions, and gather data about an environment. SNAG has already been taking temperature and humidity measurements in a remote Oregon forest using onboard sensors.

“Part of the underlying motivation of this work was to create tools that we can use to study the natural world,” Roderick said in a statement. “If we could have a robot that could act like a bird, that could unlock completely new ways of studying the environment.”