Scientists create headless flying robot bird that can perch on branches and carry objects

In place of bones there is a 3D-printed skeleton, with fishing line for muscles and tendons

Engineers at Stanford University have built a robotic bird to understand how birds are able to fly and perch on branches.

The robot has a pair of snatching talons that attach to a circular flat base; that is then attached to a quadcopter drone to fly around. To account for the size of the drone that allows it to fly, the avian robot is based on the legs of a peregrine falcon.

In place of bones, the machine has a 3D-printed structure with motors and fishing line for muscles and tendons. Each leg has its own motor to move back and forth, another for grasping, and a mechanism to absorb impact energy when it lands.

It can take as little as 20 milliseconds for the robot’s talons to close around a branch, with an accelerometer on the right foot triggering a balancing algorithm to stabilise it when it lands.

Given the acronym SNAG - stereotyped nature-inspired aerial grasper – by the engineers, the robot can catch and carry objects and perch on surfaces. It can also catch a dummy, a bean bag, and a tennis ball.

Researchers are interested in the flight of birds because it’s so difficult for humans to simulate and replicate, especially considering how birds can land on branches of various sizes and textures.

In designing the SNAG, the researchers studied parrotlets – the second smallest species of parrot – and found they performed the same manoeuvres every time. That repetition is the ‘stereotyping’ the robot performs when landing.

In the future, it is hoped that this robot could be used in search and rescue missions, wildfire monitoring, or monitoring bird life.

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