Sunday, March 23, 2014

Sub Gram Ornithopter

I can't help myself. Every time I build something I invariably think of ways I can build it smaller. I built a large ornithopter, now I have to build a small one.

This ornithopter comes in at 920mg, just under 1g, and has a 2.5" wing span. It has 4 flapping wings. The two wings on each side flap towards each other and then away from each other. This produces both thrust and lift. 

It is powered by a 8.5mAh single cell lithium polymer battery. Flight times are around 3 minutes per charge. Controls are done through an infrared receiver system which can command the throttle and rudder. The rudder is actuated with a small magnetic actuator.

The motor is a single phase brushless design that is geared 10:1 to flap the wings. The frame is all carbon fiber rod between 0.01" (0.25mm) to 0.02" (0.5mm) in diameter. The covering on the tail is OS Film while the cover on the wings is some thin grocery bag plastic film.

This is very weird to watch fly. The wings are a blur and the whole vehicle looks like its being propelled by a large dust ball. It flies quite slow and looks very much like a large insect. I wouldn't dare fly this outside.. I'm positive a bird would make a meal out of it.