sj wrote:Thanks for the replies! I ended up finding a decent usb servo control board with 18 I/O so i grabbed that and a few potentiometers and I will probably end up making a master slave system. Any tips about that would be greatly appreciated.
I haven't tried it myself (so those who have, please chime in!), but it seems like a waste of time to me. If you're custom-building your arm with servos and computer-control, why not go almost completely autonomous? The reason a master/slave system works is because we've spent 15 years developing internal kinematics for our arms, and we can map that to the robot nicely. But a computer, correctly calibrated, is even better at simultaneously controlling four or five joints.
I'd let the computer do almost all the work, pausing only briefly before picking up or dropping an object for minor manual position modifications. If you practice, you'll know exactly when to jump in and won't sacrifice any accuracy. It'll also save you a good chunk of work.