Meeting Abstract

84.3  Tuesday, Jan. 6  The ascent of freely-flying fruit flies BERMAN, Gordon*; RISTROPH, Leif; LYON, Brad; BERGOU, Attila; COHEN, Itai; WANG, Z. Jane; Cornell University; Cornell University; Cornell University; Cornell University; Cornell University; Cornell University gjb28@cornell.edu

Insects are graceful and varied locomotors — flying, darting, and hovering with ease and sophistication. This apparent effortlessness is frequently the result of the remarkably slight adjustments in wing kinematics necessary for an insect to switch from one type of flight maneuver to another. The small scale of these adaptations, however, often makes the mechanisms behind these flights difficult to investigate, as differences between maneuvering kinematics can be problematic to distinguish by studying only one or a small number of flight sequences. In this talk, we present the results from analyzing many sequences of freely-flying fruit flies ascending at various speeds in hopes of uncovering the mechanisms by which their aerodynamic climbing is accomplished. We also show how the wing kinematics of ascending insects differ from those which are hovering. The data sets used to perform this analysis are obtained from high-speed video images of a custom-made flight arena with a launch pad designed to reliably instigate ascending flight. Three-dimensional kinematics are reconstructed via a novel automated motion tracking algorithm. We show that fruit flies ascend by flapping their wings in an asymmetric ladder which counteracts the reduction in wing angle of attack accompanying a vertical trajectory.