Stepper Motors

Intro

Stepper motors are constant power motors. Unlike DC motors which rotate by create a reversing magnetic field stepper motors work by attracting a central core with magnetic coils in discrete intervals called steps.

Bipolar vs Unipolar

• Unipolar

• Bipolar (series)

• Bipolar (Parallel)

• Bipolar (series)

Drivers

• Constant Voltage (L/R)

• Constant Current (Chopper)

Stepping Schemes

• Wave Stepping
• Full Stepping
• Half Stepping
• Micro Stepping

Wiring

• 4 wire - Bipolar

• 8 wire - Unipolar or Bipolar

Steps per revolution

Common Step angle 1.8 deg (200 steps per rev)

NEMA Sizes

NEMA 17

NEMA 23

NEMA 35

Vendor List

Probotix

SparkFun

Japan Servo KH42HM2-951

References

Wikipedia

Stephen Hewitson