SK Gupta’s research group at the University of Maryland has been building robotic bird MAVs (micro-air vehicles) for the last eight years. Gupta is collaborating with Hugh Bruck, a faculty member at the university, and graduate students Luke Roberts, John Gerdes, and Ariel Perez-Rosado on a new design. These students have been working tirelessly to get this latest robotic bird concept, called Robo Raven, to take off. Robo Raven is the first robotic bird with complete control over each individual wing, enabling it to do crazy acrobatics like back flips, dives, and rolls, previously not possible with flapping wing MAV platforms.
This has been an incredibly difficult problem to solve because controlling each wing separately requires two motors and a larger LiPo battery which, in the past, have made robotic birds too heavy to fly. Gupta’s group used new manufacturing technology like laser cutting and 3D printing to create lightweight and geometrically complex Delrin™ and ULTEM (high quality lightweight nylon) parts for the bird’s body. The bird has an onboard Arduino™ microcontroller used to program wing motions which can be either coupled or completely separate, allowing programmable wing motion profiles to ensure the wings maintain the right speed to generate the right balance between lift and thrust forces. These forces are measured using a custom built test stand with a 6 degree of freedom load cell to measure the forces and torques acting on the bird simultaneously. The team also performed system level optimization to make sure all the components worked well as an integrated system. Each of these aspects were key in making Robo Raven light enough to fly.
One of the coolest things about this new robotic bird is that real birds actually mistake it for one of their own. A hawk apparently felt threatened by it and attacked Robo Raven (see 1:50 in the video) and other birds even flew in formation with (see 1:58). Though Gupta’s group wasn’t as focused on making it look so much like a bird, it was definitely a really cool result of the research.
Robotic bird MAVs will offer advances in many different applications like agriculture, where it can be used as a mobile scarecrow and monitor crops; environmental monitoring; and surveillance. Robo Raven presents a fundamentally new platform for flapping wing MAVs and is a big step in realizing true bio-inspired robotics.