[probinson]

Hi Jesse,

I don't have time to review the various links but, as nobody else has answered you, I'll touch on the torque issue.

The unipolar stepper is basically a bipolar stepper with a center tap on each of the windings. This makes the drive circuitry simpler because instead of a full bridge for each coil, power is applied to the center taps and the driver chooses polarity by connecting the appropriate end of the coil to ground. Only being able to use half of the windings at any given time is the price you pay for this drive simplicity. Less efficent use of the winding space gives a unipolar stepper motor less torque than the same motor would have in a bipolar configuration.

Pete