Several weeks ago, Professor SK Gupta of the University of Maryland finally had a breakthrough in design on a robot bird that he and his students had been working on for eight years. The end result is a flying robot that is almost indistinguishable from a bird.
Professor Gupta explains:
Our new robot is based on a fundamentally new design concept. We call it Robo Raven. It features programmable wings that can be controlled independently. We can now program any desired motion patterns for the wings. This allows us to try new in-flight aerobatics that would have not been possible before. For example, we can now dive and roll.
The new design uses two actuators that can be synchronized electronically to achieve motion coordination between the two wings. The use of two actuators required a bigger battery and an on-board micro controller. All of this makes our robotic bird overweight. So how do we get Robo Raven to “diet” and lose weight? We used advanced manufacturing processes such as 3D printing and laser cutting to create lightweight polymer parts to reduce the weight. However, this alone was not sufficient. We needed three other tricks to get Robo Raven to fly. First, we programmed wing motion profiles that ensured that wings maintain the optimal velocity during the flap cycle to achieve the right balance between the lift and the thrust. Second, we developed a method to measure aerodynamic forces generated during the flapping cycle. This enabled us to quickly evaluate many different wing designs to select the best one. Finally, we had to perform system level optimization to make sure that all components worked well as an integrated system.
Robo Raven will enable us to explore new in-flight aerobatics. It will also allow us to more faithfully reproduce observed bird flights using robotic birds. I hope that this robotic bird will also inspire more people to choose “bird making” as their hobby!
Robotic birds (i.e., flapping wing micro air vehicles) are expected to offer advances in many different applications such as agriculture, surveillance, and environmental monitoring. Robo Raven is just the beginning. Many exciting developments lie ahead. The exotic bird that you might spot in your next trip to Hawaii might actually be a robot!