In a new study, scientists have revealed how dragonflies control each of their four wings individually and manipulate fluid dynamics to fly.
Researchers from Cornell University have recorded high-speed video footage of dragonflies in flight and integrating the data into computer models, and explain that what made Dragonflies unpredictable was their ability to make a quick, sharp turn. They rarely stayed right in front of the camera for them to contemplate on, explained lead researcher Jane Wang.
In collaboration with Anthony Leonardo at Janelia Farm, the research campus of the Howard Hughes Medical Institute, Wang devised a unique experimental method to make dragonflies perform repeatable aerial maneuvers: to attach a tiny magnet to the underside of each insect that allowed them to hang upside down from a metal rod. Wang said that when the magnet was released, the Dragonflies somehow understood the orientation and did a stereotypical maneuver: they rolled their body to make a 180-degree turn.
By tracking the body and wing orientations using high-speed video recording of this rapid roll in high resolutions, the team uncovered how dragonflies were altering the aerodynamics on their wings to execute the turn.
Wang explained that unlike airplanes, insects have freedom to rotate their wings, and by adjusting the wing orientation, dragonflies could change the aerodynamic forces acting on each of their four wings.
The iridescent insects could also change the direction in which they flap their wings-known technically as their "stroke plane." The new data showed that dragonflies could adjust the stroke plane orientation of each wing independently.
The study was presented at the 67th annual meeting of the American Physical Society (APS) Division of Fluid Dynamics in San Francisco.