So I have been playing around for that last few month looking to built out my own Pan and Tilt that could run OpenMoco or other real time pan and tilt software.
I created a couple version out of wood, one out of metal, and most recently, an all acrylic version that helps to keep the material and manufacturing costs low.
My goal is to generate a design that offer the most bang for the buck by using all off the shelf parts that get the job done for the minimum cost possible.
I have been having good luck with Acetal gears, thrust bearings, and acrylic for the structural components. This combination takes the weight of my 7D + moderate weight lens without issues.
Currently I am running Easy Stepper Drivers and some $20 motors from Jameco.
I need to create some content with the latest version, but here are couple videos that created with the last iteration (it was all aluminum, but the same design).
OpenMoco SW in San Francisco at Crissy Field - http://www.youtube.com/watch?v=leDOtz_ikvE&hd=1
Homegrown SW interfaced to a Wii Nunchuck for real time precision pan and tilt - http://www.youtube.com/watch?v=bRmVb5q3okc&hd=1
Parts all in (including electronics) on this are less than $250 before labor. If there is anyone in the SF Bay Area that wants to give a prototype a run for it's money, let me know - I am interested in getting some feedback.
bcburling at gmail.com
I still need a bit of help in motor / supply voltage / driver selection, but I think the mechanical design is fairly functional. Anyone found a sweet spot they are willing to share?