How to make a tiny Ornithopter? Print it in 3D

An ornithopter with a mass of 3.89g has been constructed using the 3D printing technique and has demonstrated an 85-second passively stable untethered hovering flight. This flight exhibits the functional utility of printed materials for flapping wing experimentation and ornithopter construction and for understanding the mechanical principles underlying insect flight and control.

http://ccsl.mae.cornell.edu/ornithopter