University of Maryland Professors S. K. Gupta and Hugh Bruck and their students have developed and demonstrated a new robotic bird.

Gupta, a professor in Mechanical Engineering and the Institute for Systems Research in the A. James Clark School of Engineering, has been working on flapping-wing robotic birds for the better part of a decade. He and his graduate students, along with Mechanical Engineering Professor Hugh Bruck, first successfully demonstrated a flapping-wing bird in 2007... It even fooled a local hawk, which attacked the robot in mid-flight on more than one occasion...

But the limitation of simultaneous wing flapping restricted how well the robotic bird could fly. So Gupta decided to tackle the much thornier problem of creating a more versatile bird with wings that operated independently, just like real birds. An unsuccessful attempt in 2008 led to the project being shelved for a while. Then, in 2012, Gupta partnered with Bruck and their graduate students to try again.

"Our new robot, Robo Raven, is based on a fundamentally new design concept," Gupta says. "It uses two programmable motors that can be synchronized electronically to coordinate motion between the wings."

... the team did three more things to get Robo Raven airborne. They programmed motion profiles that ensured wings maintained optimal velocity while flapping to achieve the right balance between lift and thrust. They developed a way to measure aerodynamic forces generated during the flapping cycle, enabling them to evaluate a range of wing designs and quickly select the best one. Finally, the team performed system-level optimization to make sure all components worked well together and provided peak performance as an integrated system.

"We can now program any desired motion patterns for the wings," Gupta says. "This allows us to try new in-flight aerobatics—like diving and rolling—that would have not been possible before, and brings us a big step closer to faithfully reproducing the way real birds fly."

SF fans may be thinking fondly of the robot bird from Philip E. High's 1968 novel Invader on My Back:

When he had first built them, they had been crude indeed, flying mechanisms with little more than a reflex-response unit. Over the years, however, he had given them life and intelligence... They had developed into personalities and provided stimulating companions in his isolation. He had given them free-decision, apart from their business as bodyguards and all three had total recall...

Update 20-Dec-2025: If there were several of these Robo-Raven robot birds, you could have your own flock, like the mechanical birds from Klara and the Sun (2021) by Kazuo Ishiguro:

...the boy didn't greet us or even look our way. He had in his hands a circular device, and was looking at the sky between the two houses where a group of birds was flying in formation, and I quickly realized these were machine birds. He kept his gaze on them and when he touched his control, the birds responded by changing their pattern.

End update.