Measurement of lift and wing modal properties of dragonflies

In this thesis, we measure the average flight forces at a fixed orientation and the wing’s dynamical characteristics of dragonflies. To measure the flight force, we design a two-axis force sensor that can measure the upward and forward forces while the dragonfly is flapping its wings. The resultant of these two components represents the flight force. The wing’s dynamical characteristics are measured using the base excitation method in conjunction with two laser displacement sensors. The laser displacement sensor can measure the motion of transparent targets. In this way, we can study the effects of reflective dots put on the dragonfly’s wings by other researchers. After collecting large experimental data, we compare the wing’s dynamical characteristics of dragonflies, of the same kind and different kinds. We also study the correlation between the flight force and the geometrical dimensions and dynamical characteristics of the wings.