The robot has magical legs of a bird, can sit on a tree branch, and dress like a 'real thing'

Engineers have created a falcon-inspired robot that can take off, land, and cling to tree branches, and even catch objects in the air.

Developed by a team at Stanford University, the SNAG (nature-inspired aerial grabber) simulates the dramatic grabbing behavior of large falcons. Instead of a skeleton, SNAG has a 3D printed skeleton structure. The researchers created up to 20 versions to perfect the device. They also use motors and fishing lines instead of muscles and ligaments. Thanks to the attached 4-wing drone, the SNAG can fly around to pick up and carry objects as well as land on various surfaces.

The SNAG robot was created by a team of engineers at Stanford University.

Combining cameras and sensors, SNAG can be used to monitor climate, wildlife and natural ecosystems, contribute to forest fire prevention and search and rescue. Recent testing in a forest in Oregon showed the device can take off/land from tree branches with the help of 3D printed claws.

Like real birds, the SNAG can absorb the impact when it lands and convert it into pressure to cling to the branches. The same mechanism also allows the robot to grasp objects such as bean bags and tennis balls. The team detailed the design in the journal Science Robotics on December 1.

"Simulating birds flying and perching is not easy," said study leader William Roderick of Stanford University. "After millions of years of evolution, they fly and perch very simply, even with the most complex and varied branches you can find in the woods. Like birds, SNAGs have two legs that can move independently. This robot also has a sturdy frame and leg structure that acts like a skeleton."

Birds can perch on any branch, regardless of whether the surface is rough, wet, moss-covered, or overgrown. Building robots that simulate that behavior became a major concern for Stanford engineers. They say SNAG is an improvement on current flying robot designs, which have limited ability to pick up real objects or park after flying to save energy.

The SNAG can land on a variety of materials including wood, foam, sandpaper and Teflon like the parrotlet, the second smallest parrot species in the world. Each leg of the SNAG is equipped with a motor for forward/backward movement and another motor for grasping objects similar to the ligaments of a bird's foot.

After clinging around a branch, the SNAG's ankles locked and an accelerometer in the right foot activated a balance algorithm to stabilize the robot. According to Roderick, the SNAG motor acts like a muscle and transmits force through ligaments. When the robot touches the parking spot, the accelerometer on the foot tells it about the impact and promotes balance.

Experimenting with the robot design also allowed Roderick and his colleagues to study how film anatomy affects bean behavior. For example, they found no significant difference in perching ability between the two major toe shapes in birds. Future development of the SNAG will focus on what happens before landing, such as improving the robot's situational awareness and flight control.