The flexible dragonfly has unique aerodynamic skills, which enable it to fly upside down, hover, whirl though a tight 360-degree circle, travel at over 55 kilometres per hour, and even fly backwards.
It’s this last ability that is all the more fascinating because it appears that the dragonfly goes backwards with the same dexterity that it does when flying forward. A group of researchers, comprising Ayodeji T Bode-Oke, Samane Zeyghami and Haibo Dong, claim to have worked out exactly how the dragonfly does it (video above), presenting its findings in a paper at the Journal of the Royal Society Interface.
The scientists captured more than 40 dragonflies in the wild, placed dots on their wings, and let the insects loose in the lab to record their movements with high-speed cameras. Upon analysing the videos, they discovered that dragonflies angle their bodies upwards at 90 degrees to change the direction of the force generated by the wings, just like a helicopter. This means it’s not just the orientation of the wings that changes but the whole body that rotates.
Amazingly, the dragonfly can generate a force between two and three times its body weight while moving backwards, which means that it is capable of flying backwards for a long time. This also means that engineers may now be able to design more acrobatic and dextrous aerial robots with the same ability. (After all, we always needed aerial robots that can fly backwards.)