Building an Arduino LED Traffic Light

Introduction:

In this blog post we are going to learn how to build an LED traffic light, no matter if you are a beginner or an experienced hobbyist this project is an excellent opportunity to learn and develop your skills, by the end you will have your very own miniature traffic light that mimics the signal sequence of a real traffic intersection.

Materials Needed:

Step 1: Understanding the Traffic Light System

Begin by familiarizing yourself with the standard traffic light system- “red for stop” “yellow for caution” and “green for go”. understanding how the lights transition between states will help you design the code and circuitry.

Step 2: Setting Up the Circuit

Using the breadboard, connect the LEDs and resistors according to the circuit diagram. Make sure to use appropriate resistors to limit the current flowing through the LEDs and prevent damage.

Step 3: Writing the Arduino Code

Using the Arduino IDE software write the code to control the traffic light sequence. This involves specifying the timing intervals for each light and implementing the necessary logic to transition between states. Break down the code into functions to improve readability and maintainability.

// Pin assignments for each LED
const int redPin = 2;
const int yellowPin = 3;
const int greenPin = 4;

// Timing intervals for each state (in milliseconds)
const int greenDuration = 5000;
const int yellowDuration = 2000;
const int redDuration = 5000;

void setup() {
  // Initialize the LED pins as output
  pinMode(redPin, OUTPUT);
  pinMode(yellowPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
}

void loop() {
  // Green light
  digitalWrite(greenPin, HIGH);
  delay(greenDuration);
  
  // Yellow light
  digitalWrite(greenPin, LOW);
  digitalWrite(yellowPin, HIGH);
  delay(yellowDuration);
  
  // Red light
  digitalWrite(yellowPin, LOW);
  digitalWrite(redPin, HIGH);
  delay(redDuration);
  
  // Reset to green light
  digitalWrite(redPin, LOW);
}

Step 4: Uploading the Code to Arduino

Connect your Arduino board to your computer/pc using the USB cable. Select the appropriate board and port in the Arduino IDE Software then upload the code to the board, verify that the code works as expected and the LEDs light up accordingly.

Visit – Not uploading the code?

Step 5: Assembling the Traffic Light

If desired, you can create a housing for your traffic light using cardboard – 3D printing, or any other suitable material. Arrange the LEDs inside the housing – aligning them to represent a typical traffic light.

Remember to have fun and always prioritize safety when working with electronics. Happy making!

Download Arduino Driver