Stepper Motor Control with ULN2003 Experiment

Introduction

This experiment demonstrates how to control a stepper motor using the ULN2003 driver module. Stepper motors allow precise control of rotation, making them ideal for robotics, 3D printers, and CNC machines.

Components Needed

• Arduino (e.g., Uno, Nano)
• ULN2003 Stepper Motor Driver Module
• Stepper motor (e.g., 28BYJ-48)
• Jumper wires

Circuit Setup

1. Connect the ULN2003 module to the Arduino: IN1 to pin 8, IN2 to pin 9, IN3 to pin 10, and IN4 to pin 11.
2. Connect the stepper motor's 4 wires to the ULN2003 driver.
3. Connect the VCC and GND of the ULN2003 module to 5V and GND on the Arduino, respectively.

Ensure the circuit is properly connected before proceeding with the code.

Code for Stepper Motor Control

Upload the following code to your Arduino to control the stepper motor:

#define IN1 8
#define IN2 9
#define IN3 10
#define IN4 11

void setup() {
  pinMode(IN1, OUTPUT);
  pinMode(IN2, OUTPUT);
  pinMode(IN3, OUTPUT);
  pinMode(IN4, OUTPUT);
}

void loop() {
  stepForward();
  delay(1000);
  stepBackward();
  delay(1000);
}

void stepForward() {
  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, LOW);
  digitalWrite(IN3, HIGH);
  digitalWrite(IN4, LOW);
  delay(500);
  digitalWrite(IN1, LOW);
  digitalWrite(IN2, HIGH);
  digitalWrite(IN3, HIGH);
  digitalWrite(IN4, LOW);
  delay(500);
  digitalWrite(IN1, LOW);
  digitalWrite(IN2, HIGH);
  digitalWrite(IN3, LOW);
  digitalWrite(IN4, HIGH);
  delay(500);
  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, LOW);
  digitalWrite(IN3, LOW);
  digitalWrite(IN4, HIGH);
  delay(500);
}

void stepBackward() {
  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, LOW);
  digitalWrite(IN3, LOW);
  digitalWrite(IN4, HIGH);
  delay(500);
  digitalWrite(IN1, LOW);
  digitalWrite(IN2, HIGH);
  digitalWrite(IN3, LOW);
  digitalWrite(IN4, HIGH);
  delay(500);
  digitalWrite(IN1, LOW);
  digitalWrite(IN2, HIGH);
  digitalWrite(IN3, HIGH);
  digitalWrite(IN4, LOW);
  delay(500);
  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, LOW);
  digitalWrite(IN3, HIGH);
  digitalWrite(IN4, LOW);
  delay(500);
}
            

Explanation

This code controls the stepper motor in both forward and backward directions using the ULN2003 driver. Here's how the code works:

• digitalWrite(): Used to set the state of the IN pins of the ULN2003 driver to control the stepper motor's rotation.
• The stepForward() and stepBackward() functions control the rotation direction by energizing the appropriate pins in sequence.
• The delay(500): Provides a pause between steps, controlling the speed of rotation.

Troubleshooting

• If the motor is not moving, check the wiring to ensure all connections are secure and correct.
• If the motor is moving erratically, ensure the motor is receiving adequate power and check for any loose connections.
• Make sure the necessary libraries are installed in the Arduino IDE.