Human Flight: from small working model in footage to life size model?

March 21, 2012 8:21 AM

After seeing the Human Bird Wings video (doesn't matter if it's real or not), I thought about this TED Talk again. Are there any 3D programs/motion-capturing software that can map out that bird and its motion from the talk and convert a 3D model out of it? Then all you would have to do is scale it to human size and build it offline right?
posted by querty to Technology (3 answers total)

The real world is not scale invariant. You can't just take an arbitrary design, build it 10 times bigger and expect it to work. The problem is often the strength of materials.

Just like a roof would collapse if you made a building ten times bigger without changing the design, wings with ten times the surface area but no more strength would break up under the increased forces. If you reinforced them sufficiently, they would be to heavy to lift themselves by flapping.

Hence engines and fixed wings.
posted by caek at 8:29 AM on March 21, 2012

The problem is that mass scales with volume (r^3) but the lift force provided by the wings scales roughly with area (r^2) I believe.

So to scale a bird up to human size, you'd need to make it a whole lot lighter or make the wings a whole lot bigger. Both of those "solutions" would only cause more problems to deal with.

There's a legend that says that the architect commissioned to build the Colossus of Rhodes was bankrupted when he decided to double the height of the statue but didn't realize he would need 8 times as much material to do so. Scale matters.
posted by no regrets, coyote at 8:53 AM on March 21, 2012 [1 favorite]

There are other problems. Birds have feathers; upscaled ornithopter wings humans invent don't (AFAIK, none have). The feathers rotate slightly as the wing goes up/down, opening/closing like vents, reducing/increasing the drag on the air - so more force goes into moving air down and less is required to pull the wing up again.

But, yeah: the 3D-weight vs 2D-surface area issue is the big one.
posted by IAmBroom at 11:53 AM on March 21, 2012