A Vibration Detection System using Arduino, a vibration sensor, and a buzzer that triggers a sound alert when vibrations or movements are detected.

A Temperature and Humidity Monitoring System using Arduino and a DHT11 sensor that measures and displays real-time temperature and humidity data on the serial monitor.

A Ultrasonic Distance Measurement System using Arduino and an ultrasonic sensor that calculates the distance of an object based on the reflection time of ultrasonic waves and displays the result on the serial monitor.

An Automatic Door System using Arduino, an ultrasonic sensor, and a servo motor that detects an approaching object and opens the door automatically.