Robo-raven morphs its wings to back flip in mid-air

[Nipuna]

[media]https://www.youtube.com/watch?v=KgyfYLpT-NQ[/media]
Most robotic birds flap their wings in sync. But this raven-like flier can move each of its flexible wings independently, allowing it to perform acrobatic manoeuvres during flight.

The artificial bird, developed by Satyandra Gupta at the University of Maryland and his team, has an actuator in each wing that allows them to be programmed with different positions and velocities. This helps it to twist in flight.

Typically, a robot with multiple motors is too heavy to fly. But by using 3D printers to produce complex parts as a single piece, they lowered the weight sufficiently for take-off.

Although a hawk mistook the robot for a real bird, as seen in this video, improvements are needed to match nature's agility. The bird mimic has a narrower range of motion, lacks the fine control provided by feathers and doesn't have a body shape optimised for lift. Its tail, however, was designed to give it extra stability in the air.

The team thinks its wing system could be used in UAVs instead of propellers to make them more versatile. They plan to test different ways of flapping to see if better control of a wing's shape can reduce the need for multiple, weighty actuators.

Flexible solar cells are also being incorporated into the wings to give it additional power. "Our goal is to create a robotic bird that can do things that have never been done before," says Gupta.

Journal reference: Soft Robotics, DOI: 10.1089/soro.2014.0019