Build Your Own Smart Motion Detector That Actually Works! (ESP32 + PIR Tutorial)

Want to protect your home with a DIY solution? Create your own smart motion detector that works as effectively as commercial systems. Perfect for beginners in IoT and home automation!

What You'll Create:

• A reliable motion detection system that sends instant alerts
• Your own IoT device that works with smart home platforms
• A professional-grade security sensor you built yourself
• Automated email notifications when motion is detected

Prerequisites :

• Active AskSensors account: Create AskSensors account.
• Create a new sensor. Follow the simple process described here.

Required Hardware:

• ESP32 board
• PIR motion sensor
• Jumper wires
• 1kΩ resistor
• Breadboard
• Micro USB cable

Quick Assembly:

1. Connect PIR VCC → ESP32 5V
2. Connect PIR GND → ESP32 GND
3. Connect PIR DATA → ESP32 GPIO2 (with 1kΩ resistor)

Note: The ESP32 GPIOs require 3V3 signals (not 5V tolerent). For quick hack, you can only add a serial resistor of 1K between the PIR DATA pin and the ESP32 GPIO pin to protect the ESP32 GPIO from damage. However, for production, a 5V/3V3 level shifter is needed to guarantee long term circuit reliability. You can check this page to get a 5V/3V3 level shifter module.

Setup Instructions:

1. Prepare Your Environment

• Install the latest version of the Arduino IDE software (1.8.7 or higher).
• In your Arduino IDE, go to File> Preferences.
• Go to the “Additional Board Manager URLs” field, Enter the following URL: https://dl.espressif.com/dl/package_esp32_index.json
• If you already have the ESP8266 boards URL, separate the URLs with a comma as shown below:

https://dl.espressif.com/dl/package_esp32_index.json,http://arduino.esp8266.com/stable/package_esp8266com_index.json

• Now, open boards manager (Tools > Board > Boards Manager), search for ESP32 and click the install button for the “ESP32 by Espressif Systems”.

2. Code

• Install the MQTT PubSubClient Library for the Arduino IDE if you haven’t already.
• Download this demo from the AskSensors Github page.
• The provided code simply reads the status of the PIR sensor and send this information to AskSensors over MQTT. You need to modify the following variables:
• Your network credentials, so that ESP8266 can establish a connection with existing network
• The Api Key In and username to set the MQTT Topic:username/apiKeyIn

const char* ssid = "YOUR_WIFI_NAME";
const char* password = "YOUR_WIFI_PASSWORD";
const char* username = "YOUR_USERNAME";
const char* pubTopic = "publish/username/apiKeyIn";

3. Upload and Test

• Connect ESP32 via USB
• Check your Sensor data stream on AskSensors.
• You can cross-check the AskSensors graph readings with the values being printed on your ESP32 Serial Terminal.
• You can customize a Binary graph to plot your data as showing by next pictures.

4. Configure Email Alerts

1. Log into your AskSensors Iot platform & select your sensor
2. Click the 'Add Alert' button
3. Select 'Email Alert' as the notification type
4. Set your desired threshold values:
   • Choose 'Max Value' = 1 to detect motion
5. Enter your email address
6. Save the configuration

Now you'll receive instant email notifications whenever motion is detected!

Perfect For:

• Home security
• Smart lighting automation
• Pet monitoring
• Visitor counting
• Energy saving
• Remote property monitoring

---

This project takes only 30 minutes to complete and can be a great addition to your smart home security system. With email alerts, you'll never miss any unauthorized movement again!