Research on Flapping-Wing Flight Principle and Mechanism of the Imitating Butterfly Ornithopter A Thesis Submitted for the Degree of Master On Aeronautics and Astronautics Manufacturing Engineering by Yachao Lei Under the Supervision of Prof.Ying XU School of Aeronautical Manufacturing Engineering Nanchang Hangkong University,Nanchang,China June,2013Research on Flapping-Wing Flight Principle and Mechanism of the Imitating Butterfly Ornithopter A Thesis Submitted for the Degree of Master On Aeronautics and Astronautics Manufacturing Engineering by Yachao Lei Under the Supervision of Prof. Ying XU School of Aeronautical Manufacturing Engineering Nanchang Hangkong University, Nanchang, China June, 2013