Stepper Motor

A stepper motor often looks like a continuous DC motor, coming in round or square shapes. You can tell they are different as a stepper motor has four to eight wires coming out if it. The wires inside form coils which allow the shaft of the motor to turn very precisely.

The wire connections must be made to an electrical circuit specially made for controlling a stepper motor as it will not work by putting DC power on the wires. 

As shown below, pulses of electricity are sent to the coils in a timed manner to achieve motion.

Motion of a stepper motor (credit: Wikipedia Wapcaplet)

Steppers can turn in a full circle like DC motors and continuous servos but they can be more expensive and require electronic controllers to achieve their precise movements. Often the shaft is connected to a belt or gear for moving something.

Examples of steppers being used are with scanners, plotters, 3-D printers, etc.

Here a stepper motor is being driven with an Adafruit breakout board (credit: Adafruit)
robotics___cnc_steppers.jpg
Different sizes of stepper motors (credit: Adafruit)

Use of a Stepper with a Belt System

A belted system provides excellent control over moving something. Most plotters, CNC machines, and 3-D Printers use some variation of belts for accuracy.

Adafruit carries the GT2 belt system. There are other systems but GT2 offers advantages noted by Ladyada in this video

robotics___cnc_FSMSNEMA11-20T.jpg
A stepper using a belt and 3-D Printed Mount (credit: MIT license via GitHub user firepick1)

Steppers Available at Adafruit

Adafruit carries a number of steppers in various sizes. There are also couplers which help attach the stepper shaft to your project.

Note: It is recommended that you use 5 volt stepper motors. 12 volt stepper motors may not behave as expected.

Small Reduction Stepper Motor - 5VDC 32-Step 1/16 Gearing

PRODUCT ID: 858
This is a great first stepper motor, good for small projects and experimenting with steppers. This uni-polar motor has a built in mounting plate with two mounting holes. There are only...
$4.95
IN STOCK

Aluminum Flex Shaft Coupler - 5mm to 5mm

PRODUCT ID: 1175
Connect this to that with a set-screw coupler. These couplers are made of machined aluminum and have a spiral cut that makes them slightly flexible so they can be fit to two shafts even...
$4.95
IN STOCK

Aluminum Flex Shaft Coupler - 5mm to 8mm

PRODUCT ID: 1176
Connect this to that with a set-screw coupler. These couplers are made of machined aluminum and have a spiral cut that makes them slightly flexible so they can be fit to two shafts...
$4.95
IN STOCK
This guide was first published on Jul 04, 2018. It was last updated on Jul 04, 2018.
This page (About Stepper Motors) was last updated on Sep 23, 2020.