Design and prototype of a hovering ornithopter based on dragonfly flight

Abstract

Hovering is normally achieved using a horizontal wing path to create lift; bees, wasps and helicopters use this technique. Dragonflies hover using a unique method, by flapping along an inclined stroke plane. This seems to create a higher efficiency than is possible for normal hovering. The aim of this project is to build a mechanical model to mimic the aerodynamic properties and hovering motion of dragonflies. Through the design and evaluation of this model, we can evaluate the mechanical feasibility of reproducing the wing path using single motor control and establish whether the difference in stroke plane is advantageous for the dragonfly. By adjusting the initial angle of attack of the ornithopter's wings, we can artificially recreate varying stroke planes. A comparison of the resultant lift generated from different stroke planes showed that greater lift forces were generated with non-zero stroke planes as demonstrated in normal hovering.