A novel dragonfly dual-wing hovering flight model

Abstract

During the hovering flight of dragonflies, the coupling interaction between the forewings and hindwings leads to a reduction in the lift of each wing. Numerous scholars have reached a unanimous conclusion that under the coupling effect, the lift of the hindwings is significantly decreased. Meanwhile, the coupling of the forewings and hindwings enhances the controllability of dragonfly flight. In this article, a novel hovering flight model termed the partial advanced dual-wing model (PADM) is proposed. This model is capable of increasing the lift of both the forewings and hindwings. The maximum average lift of the forewings is increased by 18.09%, and the maximum average lift of the hindwings is increased by 41.58%. In addition to the shared advantage of enhanced positive pressure on the rear half of the wing surface due to the advanced rotation, the superior performance of the hindwings compared to the forewings is attributed to the hindwings cutting off the trailing-edge vortex ring formed by the coupling of the fore and hind wings during the downstroke phase. The vertical force and energy consumption exhibit a linear relationship with the partially advanced time, independent of the coupled aerodynamic effects. The PADM model not only sustains the weight of the dragonfly but also plays a controlling role in transitioning from a hovering flight model to a vertical leap flight model. Furthermore, it enables dragonflies and micro air vehicles to maintain hovering flight while carrying additional loads.