ornithopter
Ornithopter
"Heights by great men reached and kept were not obtained by sudden flight but, while their companions slept, they were toiling upward in the night." -Henery Wadsworth Longfellow
What is it?
An ornithopter is a machine that flys by flapping.
Ornithopter.org
Great website filled with information on the construction of ornithopters. They also have a few kits and some greaat video, they are also probly the foremost authority on the building and production of hobby type ornithopters. Check 'em out!
My ornithopter:
I have a passing interest in flapping flight. It looks good and there is something about it that is just magical. But I'm going into Electrical Engineering not aerospace. If past flying experience is any indication of things to come this thing will flap around on the ground like a small bird in it's death throws.
But being ever vigalent and having no time constraints for the project it will get done eventually and by golly we will walk away with a flapping flyer if it's the last thing we do!
Choosing Materials:
For our project ideally we need a small light weight material. Most ornithopters use balsa wood but we're going for something smaller then normal. If we were much cooler then we actually are (read that as richer) we would be making wings from titanium like these guys.
Carbon Fiber and mylar actually are my first choice, even though they say it sucks. What do those Cal Tech guys know anyway.... Besides I'm cheap, cheap enough in fact that our first iteration will not be using Carbon Fiber or even mylar. Instead we will be using fiberglass and whatever else I come across that could possibly work.
I know what you are thinking "This thing is never gonna fly." No kidding, I'm more interested in getting the flapping mechanism down and testing out materials I've never worked with before. So fiberglass it is. When we've worked out our kinks with cheap stuff we'll move onto more expensive stuff.
Construction:
The plans on building the ornithopter I got from here. Basically I shrunk them down and used different stuff that I already had. They have a good series of instructions and pictures for the construction of the ornithopter.
The wings are 8 cm long, and have a small bead glued 1cm along their length. This bead, with a bent pin inserted through it, is going to be where the flapping mechanism connects to the wing. A hinge will be constructed from the same materials attached at the body.
Here is the wing prior to gluing. That red stuff is some filler paper I got out of my wifes wrapping paper box (remember not planing on this one as a great flyer).
The main crank is turned by a rubber band or small motor on most ornithopters. There are two points on the crank (right) that will raise and fall, and are connected by another rod to the wings. This connection point is labeled in the above picture.
I've gone ahead and glued on the beads we're using as pivot points, and inserted a bent pin to test out the flapping. The pivot rod that connects the wing to the fuselage is another bent and cut pin attached in the same way in the instructions given above. That is : align the pivot rod and wing spar, wrap them with a layer of string and glue the string. The result is shown below.
At this point if you hold together the pivot rods and with your other hand move the two bottom pins in a small circle (or up and down) the wing spars will flap.
The tail is constructed exactly as described in the plans given above. Here is a shot of the tail frame as well as one of the completed tail:
Don't glue your hands together Jacob
