P.I.D. ling around with Servos by James Newton

James Newton from the MassMind organization will review P. I. D. control, and demonstrate a low cost, high power servo motor system with precise positioning (360 ticks per revolution) and potentially high speed (75,000 RPM probably) from a new non-contact magnetic quadrature encoder, an open source PIC based PID controller, and any off the shelf motor controller. (And he will explain what all that means). Basically, you can replace any little stepper motor with a DC (or other) standard motor and still have accurate positional control. This makes building really large, fast, powerful things cost effective, while still using the same motion controller (like a PC with Mach3, EMC2, or RAMPS/Marlin or Arduino/Grbl shield or whatever).