3D Scanner into RepRap

Hello RepRap community,

My name is Kiet, final year Computer Systems Engineering student at Cardiff University.

I am currently undertaking a project, which involves the redesign of an existing 3D scanner to a 3D printer (or other similar applications).
The machine is a REPLICA 500 by 3D Scanners UK Ltd. (company now liquidated). It consists of a XYZ bed and 4 dc servo motors (Parvex RX130H), which are all fitted with tachometers and encoders. Currently each motor and tacho is connected to a servo drive board (Norwin NE1710), which in turn is connected to a CNC controller (Trio Motion Coordinator Series 1) along with the encoders.

The idea is to reuse the existing positioning system, but replacing the current controller with an Arduino to issue motion signals to the drive boards. The Arduino then listens to a PC for instructions. How far do I need to go in terms of writing my own firmware to interface to the motors? Can I reuse any of the firmware/software used for RepRap?

I am relatively new to all of this and the amount of unknowns is overwhelming. I was hoping if you pros could advice me if this concept is possible and answer some of my questions.

Thanks!

What we did was kept the existing stepper motors and electronics that the RepRaps use and hooked it up to a worm gearbox to reduce the speed and increase holding torque. Seemed to work pretty well, except it'd be ideal to be able to control the DC motor through the RAMPS electronics stack, I just don't know how without a rotary encoder. Maybe a circular array of endstops?

Do you have more documentation of your setup? I'm very interested.