This is "Crowd Control: Heaven Makes a Killing," CNET's crowdsourced science fiction novel written and edited by readers from around the world. New to the story? Click here to start. To read other ...

The central focus of this series of articles is how achieving true precision requires a deeper understanding of the full motion control system, from the mechanics to the motors, drives, and controls.

[Editor’s Note: This is part 2 of a two-part series. For part 1, go to http://bit.ly/gSjOBf.] In the motor control system, current is a common item to be measured ...