fellows gear shaper change gear replacement

I'm looking at replacing the change gears on a gear shaper (and a hobber in the future).

Gear shapers work by timing the rotation of the shaper cutter to the rotation of the part as the cutter passes thru the part. shaper

The ratio of the work piece to the cutter is a function of
1. the # of teeth required on the part
2. the # of teeth on the cutter
3. the ratio of the work piece worm gear set
4. the ratio of the cutter worm gear set

The ratio is currently set by changing 4 "change gears". So you need a set of gears like this to make gears.

I would like to replace the first gear of the change gears with an encoder and the output of the change gears with a servo motor. That way I can run at any ratio and not have a wall of change gears.

This doesn't exactly fit the current programming of linux cnc but what would it take to make this work? If all goes well I would automate more of the machine.
I have a cnc mill and lathe both running linux cnc with mesa boards so i would stick with that setup if possible.

Thanks For your help

Cory

Cory, this has been done a bit and requires nothing but hardware. LinuxCNC isn't even necessary. Some servos can be wired together to be electronically geared. You tell the drives which is a master, which is a slave, what the ratio is, and the electronic gearing is taken care of for you. Very commonly done with Mitsubishi drives and servos ( MR-J2S-40A ? ) ( also Kollmorgen drives do it ), but I know that there are others that can do this as well. I did this for a very brief time with a shaper in the past to prove out the theory while I was planning to build a Hob but never followed through with it as I already own a Hob and other shiny projects came along.