Subtle frequency matching reveals resonant phenomenon in the flight of Odonata

• Published in: Journal of the Royal Society interface Vol. 21; no. 219; p. 20240401
• Main Authors: Aracheloff, C., Garrouste, R., Nel, A., Godoy-Diana, R., Thiria, B.
• Format: Journal Article
• Language: English
• Published: England the Royal Society 01.10.2024; The Royal Society
• Subjects: Animal biology; Animals; Biomechanical Phenomena; Biomechanics; Flight, Animal - physiology; Life Sciences; Life Sciences–Physics interface; Mechanics; Models, Biological; Odonata - anatomy & histology; Odonata - physiology; Physics; Structural mechanics; Wings, Animal - anatomy & histology; Wings, Animal - physiology; insect flight; Odonata; resonance; nonlinear mechanisms; Life Sciences-Physics interface Subject Areas: biomechanics systems biology Odonata insect flight resonance nonlinear mechanisms; Life Sciences-Physics interface Subject Areas: biomechanics; systems biology Odonata
• ISSN: 1742-5689; 1742-5662; 1742-5662
• DOI: 10.1098/rsif.2024.0401

In this work, we investigate the connection between the flight flapping frequency and the intrinsic wing properties in Odonata (dragonflies and damselflies). For such large flying insect species, it has been noted that the wingbeat frequency is significantly lower than the structural resonance of the wing itself. However, the structural resonance mechanism is often evoked in the literature for flying and swimming animals as a means to increase locomotion performance. Here, we show that the flight of Odonata is based on a nonlinear mechanism that strongly depends on the wingbeat amplitude. For large flapping amplitudes (as observed in natural flight), the resonant frequency of the wings decreases with respect to its value at low amplitudes to eventually match the wingbeat frequency used in flight. By means of this nonlinear resonance, Odonata keep a strong wing stiffness while benefiting from a passive energy-saving mechanism based on the dynamic softening of the wing.