This system uses an Arduino UNO with smoke, flame, and temperature sensors (like MQ, KY-026, and DHT11) to detect early signs of fire. If any sensor detects danger—like smoke, high heat, or flame—a ...

This project aims to monitor indoor air quality using an Arduino Uno microcontroller along with an MQ135 gas sensor, a DHT11 temperature and humidity sensor, and a basic LED indicator. The system is ...

A DHT11 monitors the temperature and humidity. A charge circuit and lithium battery provide power. Finally, the watch displays the date, time, and other data with an LCD from a Nokia 5110.