Abstract
Dragonflies show unique and superior flight performance than other species of insect and bird. Dragonflies move their wings twist feathering motion when they fly. They can fly highly, stop suddenly, turn sharply, or whatever by changing their feathering motion. We observed dragonfly's straight flight and hovering, and we found difference of feathering angle between their straight flight and hovering. In this study, we made flap experimental equipment which can change its feathering motion, and we measured lift and thrust forces by using it. Moreover, we also visualized around wings of the flap experimental equipment by using baby powder, and we observed velocity of powders with Particle Image Velocimetry (PINT) measurement software. From experimental results, value of lift and thrust and backwash were varied by changing the feathering angle of the wing. Consequently, it was found that dragonfly controls the lift and thrust by changing the feathering angle of the wing.
