This document presents a smart door system that uses a passive infrared (PIR) sensor to automatically open and close doors based on detecting nearby movement. The system includes an ATmega328 microcontroller, PIR sensor, relay driver IC, voltage regulator, LCD display, and other components. When the PIR sensor detects a person within its range, it sends a signal to the microcontroller to open the door. The door then automatically closes after a set time delay if no further movement is detected. The smart door system aims to provide convenience for disabled individuals and reduce contact with doors in places like hospitals.