Abstract:
The flapping of the dragonfly forewing under in vivo
condition has been analysed by image correlation
technique to get an insight of its structural dynamics.
The modal parameters such as flapping frequency,
natural frequencies, mode shapes and modal strain
have been obtained that will facilitate the biomimetic
design of wings for micro air vehicles. The stigma,
which is a pigmented spot at the leading edge of
the wing near the tip having heavier mass, takes an
active role in the real-time flapping by shaping its
trajectory as eight-shaped, which enhances the drag
coefficient and stroke efficiency. The extra mass on it
and its removal transformed the trajectory into two
different elliptical and oval shapes, respectively, which
reduced the drag coefficient and stroke efficiency of
the flapping wing by altering the flapping kinematics.
This article is part of the theme issue ‘Bioinspired
materials and surfaces for green science and
technology (part 2)’.
