1. Having initially connected the ornithopter using a DC power source, they realized that the device could lift 1.5 grams of payload, which was roughly the mass of the batteries required for flight.

2. When they experimented with a free-flying ornithopter, they needed to introduce lightweight sails above and below the winged robot in order to maintain stability (see second part of the video above).

3. Todd Reichert's ornithopter is an engineless plane that stays aloft by flapping its wings like a bird.

4. So Drs Tanaka and Shimoyama decided to build an artificial swallowtail, dubbed an "ornithopter".

5. The Canadian group says their ornithopter actually powered itself through the air, and that they have the telemetry data to prove it.

6. Researchers have managed to create a ornithopter with 3-D-printed wings weighing just 3.89 grams that can hover untethered for 85 seconds.

7. To introduce the process of manufacture in this paper,(/ornithopter.html) and to explain the performance of ornithopter by using the final design.

8. If successful, these principles could form the basis of hovering ornithopter control.

9. The Italian painter Leonardo Da Vinci made his famous sketches of the ornithopter around 1485.

10. Locally asymptotic stability is achieved with the designed smooth time-varying feedback control law, then the flight control problem of the ornithopter is solved.