It’s about the size of a quarter. Its translucent wings flap a frantic 120 times per second. Its buzz involuntarily makes you aware of the hairs on the back of your neck. It’s a robot.

The video above shows the RoboBee. It’s another step forward along two important tracks in robotics, as engineers try to miniaturize their flying machines and model them on living creatures.

Harvard scientists have been working for a decade on the design, inspired by the biology of a fly (never mind the name). Last summer, researchers got it aloft in a laboratory, and today, Harvard’s School of Engineering and Applied Sciences unveiled a video, shown above, of the RoboBee’s first controlled flight.

Shrinking a flying robot is harder than it might seem. Conventional robotic designs that rely on electromagnetic motors can’t really work with sub-millimeter-scale anatomy. To get the RoboBee in the air, Harvard scientists had to work with things called piezoelectric actuators — strips of ceramic that expand and contract when in contact with an electric field. Voila: flapping wings.

The idea is to use the teeny-tiny robot for missions like environmental monitoring, crop pollination or search-and-rescue operations, making the Bee a host body for teeny-tiny cameras. So far, the U.S. military isn’t involved in the project. But the military is moving in similar directions: the Air Force maintains a “Micro-Aviary” of miniature, experimental surveillance drones whose designs are inspired by birds and bugs.

Manufacturing challenges remain. The tether you see in the video emerging from the RoboBee’s carbon fiber frame is a connection to an external power source, which is impractical for real-world applications. Maintaining balance with a robot that weighs less than a tenth of a gram is complex.

But in a press release, the manufacturers set out high expectations for the next phases of the RoboBee project. Next up is a “computationally efficient brain” mounted on the robot to direct the Bee, inspired by the way the brains of fruit flies handle gusting winds.

“Flies perform some of the most amazing aerobatics in nature using only tiny brains,” said Sawyer B. Fuller, a postdoctoral researcher who contributes to the project. “Their capabilities exceed what we can do with our robot, so we would like to understand their biology better and apply it to our own work.”