Closed-Loop Controller

This Thing represents some of the mechanical and electrical changes needed to implement closed-loop control on a Makerbot Replicator I - class 3D printer. More complete details documenting the method used and the results obtained are available here: https://sites.google.com/site/benweisspublic/projects/imc-closed-loop-control
All the designs were done with respect to the original MakerBot Replicator I CAD files (available at this Thing); adjusting to derivative printers is straightforward. If anyone wants to modify the source SolidWorks files, I will post them too upon request.
The electronics posted here are only half the story. Other parts needed are the IMC Master electronics (documented in the IMC Project)
NOTE: This is a proof-of-concept implementation and NOT ready for prime time. I've documented what I've done, but a great deal of refining is needed before this will be a plug-and-play solution. The "Work in Progress" banner isn't a joke!
I have implemented and tested two-axis closed-loop control using these designs. It should be possible to get a whole bot running, but the design will require a separate microcontroller for each axis. If I were doing it again, I would re-write the Marlin firmware (again!) to allow both local firing of steps to Pololus and networked closed-loop control to IMC nodes. Maybe I'll get around to it, maybe somebody else will need to do it.
For other closed-loop control implementations, see this YouMagine design. It uses a simpler design philosophy and will integrate directly on top of most printer's electronics and software stack transparently.
Enjoy!



Instructions
More details (way too many details) are available here: https://sites.google.com/site/benweisspublic/projects/imc-closed-loop-control