Arduino Project 028B - Basic Stepper Control (Unipolar)

In this very simple project, you will connect up a stepper motor and then get the Arduino to control it in different directions and at different speeds for a set number of steps. You will study different types of stepper motor,  unipolar 6 wires.

Project 28 Basic Stepper Control (Unipolar)

Here's a simplified depiction of the wire winding for the two types of stepper motors.

The unipolar motor has a central common tap per phase. The bipolar motor does not.

In the schematic above, you can see a bipolar stepper motor and a unipolar stepper motor with two phases each.

A wire winding arrangement is refered to as a "phase"

The unipolar stepper motors, has one winding per phase, with a center tap. This allows the controlling circuit to operate the motor with current that flows always in the same direction. Therefore, there is no need to generate reverse current. Each time the phase is activated, only half of its coil is energized.

Unipolar motors may also have multiple (more than two) windings. However, in addition to the ends of each winding are connected to wires, the middle attaches to a third wire.

The absence of this third (common) wire means that bipolar motors are slightly easier to make.

Project 28 Components

• Arduino UNO                        1 EA

• Stepper Motor                      1 EA

• IC L293D / SN754410            1 EA 

• Ceramic Capacitor    0.01uF   2 EA

• Dupon Wire     ~ 

/* Coding Ron Wang
   Nov.18th 2024
   Autaba support for coding hardware
   Project 28  Basic Stepper Control
 */

#include <Stepper.h>
// steps value is 360 / degree angle of motor
#define STEPS 200
// create a stepper object on pins 4, 5, 6 and 7
Stepper stepper(STEPS, 4, 5, 6, 7);
void setup()
{
}
void loop()
{
 stepper.setSpeed(60);
 stepper.step(200);
 delay(100);
 stepper.setSpeed(20);
 stepper.step(-50);
 delay(100);
}

Unipolar Stepper Motor Driver Circuit and Schematic

Unipolar stepper motor have 6 wires

Unipolar Stepper Motor Circuit

Unipolar Stepper Motor Schematic

Arduino and Stepper Motor Configurations | Arduino Documentation