Microbat: A Palm-Sized Electrically Powered Ornithopter

This paper reports the successful development of “Microbat,” the first electrically powered palm-sized ornithopter. This first prototype was flown for 9 seconds in October 1998. It was powered by two 1-farad super capacitors. Due to the rapid discharge of the capacitor power source, the flight duration was limited. To achieve a longer flight, a rechargeable battery as a power source is preferred. The second prototype houses a small 3-gram rechargeable Ni-Cad battery. The best flight performance for this prototype lasted 22 seconds. The latest and current prototype is radio-controlled and is capable of turning left or right, pitching up or down. It weighs approximately 12.5 grams. So far, the best flight duration achieved is 42 seconds. The paper also discusses the study of flapping-wing flight in the wind tunnel using wings developed by MEMS technology. This enables a better understanding the key elements in developing efficient wings to achieve aerodynamic advantage in flapping-wing flight.