Meeting Abstract
Blue-tailed damselflies (Ischnura elegans) tend to navigate through dense vegetation and catch flying prey while aloft. To track an oscillating target, they tend to fix their body orientation in space and fly sideways. The ability to separate heading and flight direction may aid for gaze stabilization and visual tracking of objects that move over a stationary panorama. Here, we analyzed the wing kinematics during sideways flight to unveil how four-winged damselflies coordinate wing motions to achieve controlled sideslip. Free-flying damselflies were filmed chasing an artificial target that oscillated laterally 6 cm, at 2 Hz. During the sideslip maneuver (e.g., flying sideways to the left and then to the right with little changes in body yaw), the left forewing consistently reached a more mediocaudal and a higher position above the body’s horizontal plane. It also had a higher flapping amplitude, compared to the contralateral forewing. Maneuvering sideways in the opposite direction resulted in a mirror-image of the above asymmetry. No significant differences were observed in wing pitch, stroke plane angle and wingbeat frequency between the four wings throughout the maneuver. We suggest that other than enhancing maneuverability, controlling the fore- and hind wing separately improves objects tracking by improving gaze stability. Our kinematic analysis shows a mechanism that damselflies use to execute a complex maneuver that we believe, enhances the ability to track moving objects. Revealing the mechanism that allows four-winged insects to produce the sideslip maneuver provides a better understanding of the evolution of insect flight apparatus. It can also aid in the design of biomimetic drones that can execute complex maneuvers without compromising visual information.
