Effect of Hindwings on the Aerodynamics and Passive Dynamic Stability of a Hovering Hawkmoth

Abstract

Insects are able to fly stably in the complex environment of the various gusts that occur in nature. In addition, many insects suffer wing damage in their lives, but many species of insects are capable of flying without their hindwings. Here, we evaluated the effect of hindwings on aerodynamics using a Navier–Stokes-based numerical model, and then the passive dynamic stability was evaluated by coupling the equation of motion in three degrees of freedom with the aerodynamic forces estimated by the CFD solver under large and small perturbation conditions. In terms of aerodynamic effects, the presence of the hindwings slightly reduces the efficiency for lift generation but enhances the partial LEV circulation and increases the downwash around the wing root. In terms of thrust, increasing the wing area around the hindwing region increases the thrust, and the relationship is almost proportional at the cycle-averaged value. The passive dynamic stability was not clearly affected by the presence of the hindwings, but the stability was slightly improved depending on the perturbation direction. These results may be useful for the integrated design of wing geometry and flight control systems in the development of flapping-winged micro air vehicles.

Investigating the Mechanical Performance of Bionic Wings Based on the Flapping Kinematics of Beetle Hindwings

“…In the cycle of wingbeats, H. axyridis overcame the effect of lift reduction by increasing thrust. In addition, the aerodynamic regulation of H. axyridis was usually closely related to the changes in wingbeat kinematics, and the change in the position of the motion angle determined the aerodynamic characteristics of the hindwing [ 35 ]. In detail, the peak lift was 40.05 mN and the peak thrust was 45.88 mN.…”

“…The accuracy of the fitting results was determined using the coefficients of the Fourier series. In previous studies, the wingbeat motion functions of insects mostly used simple sine or cosine functions, which differ significantly from the real wingbeat characteristics of insects [ 35 , 38 , 39 ]. The real kinematic data of insect wings can guide the design of bio-inspired FWMAVs, so it is crucial to establish an accurate mathematical model of beetle wingbeat motion.…”

Distributed State Estimation for Flapping-Wing Micro Air Vehicles with Information Fusion Correction

“…In practical applications, the distributed information interaction network among FMAVs is susceptible to information incompleteness phenomena, encompassing missing sampling signals, time delays, and various internal or external interferences. These factors inevitably compromise overall estimation performance, impacting the accuracy and reliability of the entire system [ 15 , 16 , 17 , 18 , 19 ]. Consequently, the effective integration of interaction information within the FMAV network is crucial for achieving efficient, prompt, and reliable distributed state estimation.…”

Clap-and-Fling Mechanism of Climbing-Flight Coccinella Septempunctata

“…It is exceedingly challenging and practically unfeasible to directly gauge the aerodynamic forces and moments acting on a freely flying insect and to map the flow field around the wings. To overcome the challenge of direct measurement, researchers can employ experimental or numerical methods to estimate the aerodynamic forces and moments on model wing replicas of insect wings [9,[15][16][17][18].…”