I recently picked up a robotic arm from a university-used store. It has 2 axis on its arm (shoulder and elbow) as well as a vertical "hand" that can go up and down, as well as rotate. So it has 4 motors total, all of them unipolar stepper motors. And all but the hand rotate motor have pots for detecting rotation. Now the problem is, it has no controller. I believe all the motors are RapidSyn. They seem pretty tough and one of them can even take up to 14 amps. So my question. What is the best way to get a computer controller for this? I want cheap, as cheap as possible. I already have a good power supply. I also have a home-brew basic stamp. I am not afraid to build my own circuit, even make my own PCB. I just need the plans. Let me know what you all think. Also I have pictures if anyone wants to see this thing, it was a great deal at $40!

You might want to post the brand of machine with some pics. There may be someone here that has already done some of this and can save you some time. :)

Other than controlling it, what is the ultimate goal for the machine. If it is a school project, 'nuff said. Lord knows I've had plenty of those!