Abstract
We developed a motor-driven ornithopter for investigating the relationship between flapping frequencies and flight kinematics of insects. Wings were designed to have 150 mm span so that Reynolds number of the ornithopter was the same order as that of insects (Re〜10^4). Flights of the ornithopter were recorded with a high speed video camera in flapping frequencies from 9.9 Hz to 13.3 Hz, and their motions were analyzed. We clarified the mean angle of attack decreased as the flapping frequency became higher. We also developed FM-telemetry system to measure directly aerodynamic forces generated by wings in free flight. The telemeter was miniaturized to attach to the ornithopter. The total size and weight were respectively 30 mm×15 mm and 1.33 g. To estimate aerodynamic forces, we measured the moment of the leading edge of the wing with strain gages. We found the difference of aerodynamic forces between in free flight and in tethered state.
