Hey Doug, thanks!
Funny that you should mention focus stacking, I’ve been wanting to do that for quite a while now.
The issue is that while Gphoto2 supports focus set points and pecking, you cant use it to determine focus without using liveview, and thats out of the bouds of where I wanted to take this for many different reasons.
It is camera specific though, so I dont really have good access to focus controls on the Canon 6D that I use, but it is something that I want to investigate more in the future.
I use this setup mainly for astro photography and night-scapes, so I am using a very wide angle lens (Samyang 14mm) and it’s manual focus, so I havent needed focus control.
The system will support using the either of the three axis for anything that you want though, so the slider channel could be used for a focus motor that drives to whatever set points you want, you’d just need to add a toothed ring to the lens and the same encoder motor that Im using.
Have a look at the other project that I just posted as it compliments this one.
The current software support almost any Canon camera and almost any Nikon Camera, Ive not added any others at this time, however it should be relatively simple to add other manufacturers.
The software is designed to add additional ‘CameraTerminology’ records into the db that lets the system use the specific term that the camera reports to Gphoto2
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However, it would require some tweaks as I think that it is currently only looking for Canon or Nikon manufacturers. I’ll check that.
The web control part is totally custom.
There’s custom PHP pages that call custom python scripts to perform the actions, Gphoto2 is the library used for the camera interface.
I’ve ben building this system for about 8 years now with a mate, I have Canon, he has Nikon, that is why those are the two supported camera types.
Last month we released the system to someone else that has a lower end Canon and it all worked fine and he is using the system without too many hiccups, so that is a benefit that we didnt expect.
About 4 months ago I tested with someone else that has a lower end Nikon and it also worked without hiccup.
I think that we are getting very close to the point that we want to release to a wider audience, however in order to do that I will need to write up a good set of documentation and we would need to offer support for other camera manufacturers.
If you’re willing to be a guinea pig then I can see what I can do 
Heres a few pics of my setup for time-lapses.
