About this 3D model

This is a project to make an opensource robot that moves like a dog. Right now this project is more of an OpenSCad tutorial than anything else. However, I will be covering more aspects of the design when I have time.The tutorial is in the form of a 10 minute youtube video. Episode 1 http://www.youtube.com/watch?v=LmKnvEcPTk8The OpenSCad source code in this video is included at the bottom. I am intentionally not including STL files for now as I know the design will change.Episode 2 "DogBot Math":http://www.youtube.com/watch?v=qaqrHuw4qY8The Source files for this episode are included at the bottom in a zip file. Thanks goes to tbuser and http://www.thingiverse.com/thing:2054 for supplying the openscad fonts. Episode 3 "DogBot Electronics": http://www.youtube.com/watch?v=8-Y19SUuzC8Epsiode 4 "Dogbot Learns to Feel, Part 2":http://www.youtube.com/watch?v=XgJe5fNaTj0UPDATE:(7/11/2011) Episode 5 is now available:http://www.youtube.com/watch?v=sfWb2gXHOMg