How to Control a Servo Motor with Arduino

Introduction

Servo motors are widely used in robotics, automation, and DIY projects because they allow precise control over angular movement. In this tutorial, we will learn how to control a basic servo motor using an Arduino. This project will introduce you to the Servo library, one of the most commonly used libraries in Arduino programming.

What You Will Need

Arduino Uno board
Servo motor (such as SG90)
Breadboard (optional)
Jumper wires
USB cable for programming

Understanding the Servo Motor

A servo motor has three wires:

Power (usually red): Connects to 5V
Ground (usually black or brown): Connects to GND
Signal (usually yellow or orange): Receives control signals from Arduino

The Arduino sends a PWM (Pulse Width Modulation) signal to the servo motor to set its position.

Setting Up the Hardware

Connect the servo motor’s power wire to the 5V pin on the Arduino.
Connect the ground wire to one of the GND pins on the Arduino.
Connect the signal wire to digital pin 9 on the Arduino.

If you are using a breadboard, you can connect the wires more neatly, but direct wiring will also work for simple projects.

Writing the Code

Open the Arduino IDE and type the following code:

cppCopyEdit#include <Servo.h>

Servo myServo; // Create a servo object

void setup() {
  myServo.attach(9); // Attach the servo to pin 9
}

void loop() {
  myServo.write(0);   // Move servo to 0 degrees
  delay(1000);        // Wait for 1 second
  
  myServo.write(90);  // Move servo to 90 degrees
  delay(1000);        // Wait for 1 second
  
  myServo.write(180); // Move servo to 180 degrees
  delay(1000);        // Wait for 1 second
}

How the Code Works

#include <Servo.h>: This imports the Servo library, which contains all the functions needed to control a servo motor.
Servo myServo;: Creates an instance of the Servo class to control the motor.
myServo.attach(9);: Links the servo object to pin 9.
myServo.write(angle);: Commands the servo to move to the specified angle, between 0 and 180 degrees.
delay(time);: Waits for the specified time in milliseconds before moving to the next position.

Conclusion

Controlling a servo motor with Arduino is simple and powerful. With just a few lines of code, you can create projects involving movement, such as robotic arms, automatic door openers, and sensor-driven mechanisms. Once you master basic servo control, you can move on to more complex applications like controlling multiple servos simultaneously or using joystick inputs.