The invention relates to an aircraft in fluid media (air or water), particularly to a scheme for improving the
flapping intensity of
flapping-wing aircrafts. The breakthrough on miniature
flapping-wing aircrafts is realized, and however, except miniature flapping-wing aircrafts, high-efficient manned flight cannot be realized so far due to the rigorous requirements for materials. In order to improve the flapping intensity of flapping-wing aircrafts, the invention provides the scheme for improving the flapping intensity of flapping-wing aircrafts. The flapping-wing aircraft comprises an aircraft body, flapping wings, and a flapping mechanism, wherein each
flapping wing consists of a wing bar and a
wing membrane, and each
wing membrane is attached to the corresponding wing bar; the flapping mechanism consists of double-
crank hinge mechanisms, usually, the flapping wings of a flapping-wing aircraft or an
insect are connected with bodies through one position (usually called
wing root), and due to the low intensity of materials, artificial flapping-wing aircrafts cannot realize manned flight. The scheme provided by the invention has the benefits that at least two positions of each
flapping wing are connected with the aircraft bodies through the double-
crank mechanisms, so that the requirements for the intensity of the materials of the flapping wings are substantially reduced; motors mounted on the aircraft bodies enable the flapping wings to vibrate through the double-
crank mechanisms, so that the high-efficient flight of the flapping-wing aircraft is realized.