How to Use Stepper Motor with Arduino?

1.Introduction
 

Stepper motors are accurately positioned and are the most important components in industrial robots, 3D printers, large lathes, and other mechanical devices. In this project, we will use a stepper motor and a clock paper card to make a clock model.
 

2.Components Required
 

3.Component Knowledge

Stepper motor:
 

It is a motor controlled by a series of electromagnetic coils. It can rotate by the exact number of degrees (or steps) needed, allowing you to move it to a precise position and keep it there. It does this by supplying power to the coil inside the motor in a very short time, but you must always supply power to the motor to keep it in the position you want. There are two basic types of stepping motors, namely unipolar stepping motor and bipolar stepping motor.

In this project, we use a 28-BYJ48 unipolar stepper motor.

Working Principle:
 

The stepper motor is mainly composed of a stator and a rotor. The stator is fixed. As shown in the figure below, the part of the coil group A, B, C, and D will generate a magnetic field when the coil group is energized. The rotor is the rotating part. As follows, the middle part of the stator, two poles are permanent magnets.

Single -phase four beat: At the beginning, the coils of group A are turned on, and the poles of the rotor point at A coil. Next, the group A coil are disconnected, and the group B coils are turned on. The rotor will turn clockwise to the group B. Then, group B is disconnected, group C is turned on, and the rotor is turned to group C. After that, group C is disconnected, and group D is turned on, and the rotor is turned to group D. Finally, group D is disconnected, group A is turned on, and the rotor is turned to group A coils. Therefore, rotor turns 180° and continuously rotates B-C-D-A, which means it runs a circle (eight phase). As shown below, the rotation principle of stepper motor is A - B - C - D - A.

You make order inverse(D - C - B - A - D …..) if you want to make stepper motor rotate anticlockwise.

Half-phase and eight beat: 8 beat adopts single and dual beat way，A - AB - B - BC - C - CD - D - DA - A ……, rotor will rotate half phase in this order.

For example, when A coil is electrified, rotor faces to A coil then A and B coil are connected, on this condition, the strongest magnetic field produced lies in the central part of AB coil, which means rotating half-phase clockwise.

Stepper Motor Parameters:
 

The rotor rotates one circle when the stepper motor we provide rotates 32 phases and with the output shaft driven by 1:64 reduction geared set. Therefore the rotation (a circle) of output shaft requires 2048 phases

The step angle of 4-beat mode of 5V and 4-phase stepper motor is 11.25. And the step angle of 8-beat mode is 5.625, the reduction ratio is 1:64.
 

ULN2003Stepper Motor Drive Board: It is stepper motor driver.

The following schematic diagram shows how to use the ULN2003 stepper motor driver board interface to connect a unipolar stepper motor to the pins of the Plus control board, and shows how to use four TIP120 interfaces.

4.Schematic Diagram and Wiring Diagram
 

5. Code
 

/*
Stepper_motor
http//www.keyestudio.com
*/
// pins of the stepper motor
const int IN1_pin = 11;
const int IN2_pin = 10;
const int IN3_pin = 9;
const int IN4_pin = 8;
int val; 
void setup() {
Serial.begin(9600);
// the setting of pins of stepper motor in Arduino
pinMode(IN1_pin,OUTPUT);
pinMode(IN2_pin,OUTPUT);
pinMode(IN3_pin,OUTPUT);
pinMode(IN4_pin,OUTPUT);
}
void loop() {
int a = 1024;
int b = 1024;
val=Serial.read();
if(val=='A')
{
while(a--)
{
digitalWrite(IN1_pin, HIGH);
digitalWrite(IN2_pin, LOW);
digitalWrite(IN3_pin, LOW);
digitalWrite(IN4_pin, LOW);
delay(10);
digitalWrite(IN1_pin, LOW);
digitalWrite(IN2_pin, HIGH);
digitalWrite(IN3_pin, LOW);
digitalWrite(IN4_pin, LOW);
delay(10);
digitalWrite(IN1_pin, LOW);
digitalWrite(IN2_pin, LOW);
digitalWrite(IN3_pin, HIGH);
digitalWrite(IN4_pin, LOW);
delay(10);
digitalWrite(IN1_pin, LOW);
digitalWrite(IN2_pin, LOW);
digitalWrite(IN3_pin, LOW);
digitalWrite(IN4_pin, HIGH);
delay(10);
}
}
if(val=='C')
{
while(b--)
{
digitalWrite(IN4_pin, HIGH);
digitalWrite(IN3_pin, LOW);
digitalWrite(IN2_pin, LOW);
digitalWrite(IN1_pin, LOW);
delay(10);
digitalWrite(IN4_pin, LOW);
digitalWrite(IN3_pin, HIGH);
digitalWrite(IN2_pin, LOW);
digitalWrite(IN1_pin, LOW);
delay(10);
digitalWrite(IN4_pin, LOW);
digitalWrite(IN3_pin, LOW);
digitalWrite(IN2_pin, HIGH);
digitalWrite(IN1_pin, LOW);
delay(10);
digitalWrite(IN4_pin, LOW);
digitalWrite(IN3_pin, LOW);
digitalWrite(IN2_pin, LOW);
digitalWrite(IN1_pin, HIGH);
delay(10);
}
}
digitalWrite(IN4_pin, LOW);
digitalWrite(IN3_pin, LOW);
digitalWrite(IN2_pin, LOW);
digitalWrite(IN1_pin, LOW);
}

6. Result
 

Upload the project code to the PLUS Mainboard, wire up and power on first. Then open the serial monitor, set the baud rate to 9600. We enter “A” in the serial monitor and click “send”, the stepper motor rotates counterclockwise rotation. Enter “C” in the serial monitor and click “send”, the stepper motor rotates clockwise.