43.7 Thursday, Jan. 5 Rock and Roll - how do flies recover from aerial stumbles? BEATUS, T.*; RISTROPH, L.G.; MOROZOVA, S.; IAMS, S.M.; WANG, Z.J.; GUCKENHEIMER, J.M.; COHEN, I.; Cornell University; Cornell University; Cornell University; Cornell University; Cornell University; Cornell University; Cornell University firstname.lastname@example.org
Flying insects manage to maintain aerodynamic stability despite the facts that flapping flight is inherently unstable and that they are constantly subject to mechanical perturbations, such as gusts of wind. To maintain stability against such perturbations, insects rely on fast and robust flight control mechanisms, which are poorly understood. Here, we directly study flight control in the fruit fly D. melanogaster by applying mechanical perturbations in mid-air and measuring the insects' correction maneuvers. We glue small magnets on the flies and use pulses of magnetic field to apply torque perturbations along the flies' roll axis, which is, as we show, an unstable degree-of-freedom. We then use high-speed filming and 3D hull-reconstruction to characterize the detailed kinematics of their correction maneuver and show how the flies fully recover from roll perturbations of up to 60 degrees within 7-8 wing beats (30-40ms), which is faster than the visual response time. Finally, we show that this correction maneuver can only be explained by a nonlinear controller. This control mechanism is qualitatively different from the linear controller used for correcting perturbation in yaw. These results have implications ranging from the neurobiological mechanisms that underlie flight control to the design of flapping robots.