The damping and structural properties of dragonfly and damselfly wings during dynamic movement

For flying insects, stability is essential to maintain the orientation and direction of motion in flight. Flight instability is caused by a variety of factors, such as intended abrupt flight manoeuvres and unwanted environmental disturbances. Although wings play a key role in insect flight stability, little is known about their oscillatory behaviour. Here we present the first systematic study of insect wing damping. We show that different wing regions have almost identical damping properties. The mean damping ratio of fresh wings is noticeably higher than that previously thought. Flight muscles and hemolymph have almost no 'direct' influence on the wing damping. In contrast, the involvement of the wing hinge can significantly increase damping. We also show that although desiccation reduces the wing damping ratio, rehydration leads to full recovery of damping properties after desiccation. Hence, we expect hemolymph to influence the wing damping indirectly, by continuously hydrating the wing system. Lietz, Rajabi and colleagues investigate the physiological and structural components of damping in insect wings. Notably, flight muscles and hemolyph appear to have no direct involvement in wing damping, compared to the function of the wing hinge.

Automated summary

The study systematically investigated damping in insect wings for the first time, finding that different wing regions have almost identical damping properties, fresh wings have a higher damping ratio than previously thought, and flight muscles and hemolymph have almost no direct influence on wing damping.