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Abstract Flying insects have a robust flight system that allows them to fly even when their forewings are damaged. The insect must adjust wingbeat kinematics to aerodynamically compensate for the loss of wing area. However, the mechanisms that allow insects with asynchronous flight muscle to adapt to wing damage are not well understood. Here, we investigated the phase and amplitude relationships between thorax deformation and flapping angle in tethered flying bumblebees subject to wing clipping and weighting. We used synchronized laser vibrometry and high-speed videography to measure thorax deformation and flapping angle, respectively. We found that changes in wing inertia did not affect thorax deformation amplitude but did influence wingbeat frequency. Increasing wing inertia increased flapping amplitude and caused a phase lag between thorax deformation and flapping angle, whereas decreasing wing inertia did not affect flapping amplitude and caused the flapping angle to lead thorax deformation. Our findings indicate that bumblebees adapt to wing damage by adjusting their wingbeat frequency rather than altering their wing stroke amplitude. Additionally, our results suggest that bumblebees operate near a wing-hinge-dominated resonant frequency, and that moments generated by steering muscles within the wing hinge influence the phase between thorax deformation and wing stroke nontrivially. These insights can inform the design of resilient, insect-inspired flapping-wing micro air vehicles.
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Aerodynamic Forces and Wake Analysis of Wing Damaged Flapping Flight
Flapping flight is a commonly used mechanism of micro aerial vehicles and insects alike. Dragonflies use their four-winged anatomy to navigate the environment, maneuver around obstacles, and perform other essential flight patterns. The flight performance and aerodynamics of intact flapping wings is well known; however, this study aims to clarify how wing damage affects the flight performance. First, high speed videos of the damaged wing flight, a takeoff performed by a dragonfly, is captured, and subsequently digitally reconstructed to create a three-dimensional model. Second, using an immersed-boundary method (IBM) based incompressible Navier-Stokes direct numerical simulation (DNS) solver, we resolve the aerodynamic forces and wake topology of the dragonfly’s damaged wing flapping flight in high detail. We found that spanwise damage doesn’t cause any detriment to the force capabilities of the damaged wing which is due to increased pitch angles of the damaged wing. As a consequence, fliers with spanwise damaged and intact wings may be able to utilize similar strategies to achieve takeoffs. The wake topology of the wing damaged flight is also examined. This work serves as a baseline for studying the effect of wing damage for flapping flight and could provide useful insights to micro-aerial vehicle (MAV) designers as some degree of wing damage may be an inevitable occurrence for winged fliers.
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- Award ID(s):
- 1931929
- PAR ID:
- 10473222
- Publisher / Repository:
- American Institute of Aeronautics and Astronautics
- Date Published:
- ISBN:
- 978-1-62410-699-6
- Format(s):
- Medium: X
- Location:
- National Harbor, MD & Online
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.2514/6.2023-0463
