By examining how fruit flies use eye movements to enhance flight control with a staggeringly fast reaction speed — about 30 times faster than the blink of an eye — researchers have detailed a framework to mimic this ability in robotics. The team studied the motions of fruit flies tethered in a virtual reality flight simulator constructed with LED lights and recorded using high-speed cameras.
The team was able to determine how fruit flies use eye movements to quickly coordinate their wings in response to what they were seeing. Since fly eyes are fixed to the head, the researchers tracked head movements to infer where the flies were looking. Stabilizing gaze is an ordinary phenomenon that most living things can do; for example, humans seamlessly move their eyes, head, and/or body to scan a room.
While much of the previous research in this area has focused on wing movements, understanding how animals like flies use active eye movements to control flight could greatly enhance robotics. Currently, most robots have stationary sensors, keeping sensing and movement decoupled. But by better emulating the eyes and brain through the coordination of visual sensors capable of moving on the body, the flight control of robots could be vastly improved.
To support this theory, the researchers determined the eyes of the fruit fly were able to react four times faster than the body or wings of the animal. These reactions were also tightly coupled, demonstrating that flies rely heavily upon eye movements to coordinate their wing movements. Their eyes can control and stabilize their vision better than originally thought by reducing motion blur.
In addition, they found that when the flies had glue carefully applied to their heads and then recorded in the virtual reality flight simulator, the restriction of their head movements had a dramatic impact on flight performance. An important principle discovered was that fly eyes slow down visual motion that goes into the brain and this process enhances their flying behavior. Demonstrated in this work, the researchers believe unlocking the secrets of the biological world could have broad implications for technology.