Password-Based Door Lock using Keypad and Arduino

The Password-Based Door Lock system is a secure and interactive project using an Arduino Uno, 4×4 matrix keypad, and a servo motor or electronic lock. It allows access only when the correct password is entered, making it a great introduction to digital security and access control systems.

The user inputs a numeric password through the keypad, which sends the data to the Arduino. The Arduino compares the entered password with a predefined one stored in its memory. If the password is correct, the Arduino sends a signal to the servo motor, which rotates to simulate unlocking a door. An incorrect password results in a denied access message on the 16×2 LCD display, and optionally, an alarm or buzzer can be triggered.

This project is excellent for learning about user input handling, data comparison, and output control using Arduino. It demonstrates the basics of embedded security systems and can be expanded with RFID, fingerprint modules, or IoT integration for advanced access control.