difference btwn servo and stepper

[ajl6549]

I've read some about but am still alittle lost what is a "stepper"? I'm familiar with servo's but...

just curios A.J.L

[Al_The_Man]

You should find rafts of information by Google, but the main feature of a stepper is it is an index motor, it is controlled by a digital pulse that indexes the armature a fixed/constant angle for every pulse.
Generally the maximum torgue of a stepper motor is when it is operated at its rated voltage and current at rest (holding torque).
Probabally Oriental motor, PcSci & Superior Electric should have any info you are looking for.
Al.

[CNCAddict]

As for functionality...

Steppers--easy to tune, reliable when run at reasonable speeds, noisy, inexpensive drive, low resolution (even with microstepping), stall if they hit an obstruction, if pushed to the limit they can lose steps (without you knowing)

Servos--can be very hard to tune for high performance, a lot more connections to screw up, can be very quiet, can be very fast, much more efficient than steppers, obstructions can cause big problems if the software current limit isn't set correctly, system must have very little compliance and high stiffness, sometimes can have large following errors, very expensive, a lot sexier than steppers