We've been trying to create robots that mimic natural bird-flight for years, but they've only ever achieved a crude imitation. This is largely because, unlike the robots, real birds can move their wings independently.
But now a research team from the Maryland Robotics centre has created the Robo Crow, a mechanical flyer so biologically accurate that hawks keep hunting (and dive bombing) the prototypes.
Developed with funding from the US Army Research Laboratory, the Robo Raven measures just under 60cm long. Its hollow skeleton (just like a real bird's) is made of 3D-printed thermal-resistant plastic, foam and carbon with Mylar foil stretched over to constitute wings and a tail. Dr SK Gupta, a professor in mechanical engineering at UMD, has been working on the design since 2007, however development has been slow due to the one-off prototypes continually crashing, breaking and being attacked by raptors.
"Robo Raven attracts attention from birds in the area," John Gerdes, an engineer at the Army’s Aberdeen Proving Ground, told Military.com. "[Hawks] will dive and attack by hitting the bird from above with their talons; then, they typically fly away," whereas seagulls and other prey birds will line up in formation behind it.
These attacks are prompted by the Robo Raptor's uncannily lifelike flapping. Until now, all flapping flyers from experimental military ISR drones to the $US30 toys at Walmart have flapped their wings in unison -- both go up, both go down, that's it. This severely limits the robot's mobility so instead, the Maryland researchers figured out how to power and control them independently. This enables the Robo Raven to perform previously-impossible acrobatic aerial maneuvers like rolls and dives.
"Our new robot, Robo Raven, is based on a fundamentally new design concept," Gupta said in a news release. "It uses two programmable motors that can be synchronised electronically to coordinate motion between the wings." A handheld R/C controller provides the basic trajectory input. Eat your heart out Bubo.