Clapping wing air vehicles are inspired by the Weis-Fogh clap and fling mechanism used by certain insects, where opposing wings almost touch during part of the flap cycle, spawning vortex structures that increase thrust. Current vehicles cannot be scaled to Nano Air Vehicle (NAV) dimensions because they use electromagnetic motors, gears, and linkages that are difficult to fabricate and have poor efficiency at the sub-millimeter scale. This paper develops a novel NAV that uses piezoelectric T-beam actuators that are monolithically fabricated and exhibit unimorph behavior. A hinge and lever wing mechanism amplifies the small actuator displacements to produce large wing motions. A four wing, clapping NAV is designed, fabricated, and experimentally shown to provide a wing stroke angle of approximately 35° at 1 Hz.
An experimental study of the vortex structures in the wake of a piezoelectric flapping plate for Nano Air Vehicle applications