I have 2 old Cd Drives which have steppers. I was thinking about making a simple plotter by using one for the X axis and one for they Y axis. I understand what i need to do for hardware side of things, but am clueless what to do on the software side. I was thinking of making it able to read and print .plt files. How should i go about the software side of this project?
Thanks in advance!
Better look at the hardware side first - what kind of steppers? 4 wire, 5 wire? 4 wire are bipolar and those with more wires are generally unipolar. Each has its own set of benefits and problems. A bipolar stepper will require 2 H-Bridges to operate. and Unipolar will need 4 transistors - depending on current either NPN or MOSFETs.
There are several folks who have done some work with CNC plotters/routers/mills. Might look up what some of them have done.
I have done some work using first the Arduino and then an ATtiny2313 as the logic for a stepper driver - they take Step/Direction inputs and supply 4 control signals to the 4 transistors for an unipolar stepper drive. Here's the link - http://arduino.cc/forum/index.php/topic,84809.0.html
Thankyou for your reply. Ill take a look at these. Actually, what i meant was that i have already covered all the hardware part, and thankfully i know all about the hardware involved. I had tried this many years ago but failed on the software part :(. Could you tell me what to do on the software part? Im thinking of using HPGL to generate coordinates from vector images.
@kf2qd: unipolar (5 or 6 wire) steppers are essentially just centertapped bipolar motors and can be driven as such by simply ignoring the extra ground wire(s). So a dual h-bridge will do the job regardless of type.
@OP: I've ripped apart many dead drives and if the motors you are referring to are the ones I'm thinking of then they're the center spindle motors, they are 3 phase brushless, not steppers, and are a lot more complex to drive without a purpose-built controller. If they are the laser carriage motors with the lead-screw shaft, the slider frame usually doubles as the front bearing and the motors won't work mechanically if removed