Creating limbs with AS 3.0

I wonder how I might create a kinematics structure to create a character with limbs.
(really, how they did this-http://levitated.net/exhibit/organicMachine/index.html)
I am using actionscript 3.0 and I wonder how to create the child-parent animation structures that would make the animation you see there possible.

BTW- I have seen references to using an Elastic Mesh Generator, but I don’t need anything that elaborate. I would be using “limbs” created as images with alpha channels, and these would merely rotate, not change perspective in 3d as I figure would be much more complex.