Stepper motors

Stepper motors do some things very well. High-accuracy positioning with no feedback required is one of them. Some other advantages to using step motors are:

1) Stable. Can drive a wide range of frictional and inertial loads.

2) Needs no feedback. The motor is also the position transducer.

3) Inexpensive relative to other motion control systems.

4) Standardized frame size and performance.

5) Plug and play. Easy to setup and use.

6) Safe. If anything breaks, the motor stops.

7) Long life. Bearings are the only wear-out mechanism.

8) Excellent low speed torque. Can drive many loads without gearing.

9) Excellent repeatability. Returns to the same location accurately.

10) Overload safe. Motor cannot be damaged by mechanical overload.

Gecko Drive               

These guys sell several stepper motor drivers, well-designed, easy to use, and economically priced. They also sell the motors. They also sell servo-motor drivers. The website has a comprehensive FAQ, and good tutorials and how-to's. Be sure to check out their Support page. Highly recommended.