How to Build a Simple Arduino-Based Motion Detector in Just 10 Minutes


Building a motion detector with an Arduino is a fun electronics project that can be completed in just 10 minutes! With a few basic electronic components, you can make your own motion sensing device that can detect movement and trigger actions.

In this article, I will show you step-by-step how to build a simple motion detector using an Arduino Uno board, a passive infrared (PIR) motion sensor, an LED, and some jumper wires. No prior experience with Arduino or electronics is required to follow this tutorial.

What You Will Need

To build the Arduino motion detector, you will need the following components:

That's it for supplies! Make sure you have all the components listed above before starting this project.

Step-by-Step Instructions

Follow these step-by-step instructions to build your own motion detector with Arduino:

1. Set up the motion sensor

The PIR motion sensor has three pins - ground, power, and output. Using jumper wires, connect the ground pin to a ground pin on the Arduino, the power pin to the 5V pin on the Arduino, and the output pin to digital pin 2 on the Arduino. This allows the Arduino to receive the output signals from the sensor.

2. Connect the LED

Using jumper wires, connect the positive leg of the LED to digital pin 13 on the Arduino, and the negative leg to ground. Later, we'll program the Arduino to turn the LED on when motion is detected.

3. Load the Arduino code

Open the Arduino IDE on your computer. Copy the following code and paste it into a new sketch:

int pirPin = 2; //input pin for PIR sensor
int ledPin = 13; //output pin for LED

void setup() {
pinMode(pirPin, INPUT);
pinMode(ledPin, OUTPUT);

void loop() {
int motion = digitalRead(pirPin);
if (motion == HIGH) {
digitalWrite(ledPin, HIGH); //turn on LED
else {
digitalWrite(ledPin, LOW); //turn off LED

This initializes the pins, reads the input from the sensor, and controls the LED output.

4. Upload the code

With the Arduino connected to your computer, upload the code. This will run the program on the Arduino.

5. Test it out!

Once uploaded, open the serial monitor in the Arduino IDE. Walk in front of the sensor. You should see the LED turn on when motion is detected!

Customizing Your Project

This simple motion detector can easily be expanded:

The possibilities are endless! With just a basic understanding of Arduino programming, you can create more advanced projects.


Building a motion detector with Arduino is an easy, fun project that can be completed in just 10 minutes! With minimal components, you can gain hands-on experience working with sensors and programming.

Use this project as a jumping off point to spark your creativity in designing more complex Arduino-based devices. The Arduino platform makes it simple to prototype and build electronic projects, even with no prior experience.

So grab your Arduino and give this motion detector a try. See if you can modify or expand on the project to make it your own!