Investigation of wing interaction by using a beetle-inspired flapping system

In this work, we investigated interaction between the elytra (forewings) and hind-wings of a beetle, Allomyrina Dichotoma, and aerodynamic force enhancement by the wing interaction. Instead of using a live beetle, we have created a beetle-mimicking flapping-wing system for the investigation. We first have visualized flow around the wings during flapping motion and captured images using a high-speed camera. The images are examined to understand how flows are changed due to the wing interaction for various inflow velocities. Flow is accelerated over elytra by the vortices generated by the hind-wings. Due to the presence of elytra, a trailing edge vortex is produced earlier in the hind-wing, while generation of a leading edge vortex is delayed. This mechanism may enhance force generation in flight.