RFID & Keypad based Door Lock

Problem statement

Mechanical locks can be lost or copied easily and do not provide electronic access logging.

Abstract

The RFID and keypad based door lock uses contactless RFID cards and a numeric keypad to control a door. An Arduino checks the card ID or PIN code and drives a servo or solenoid lock when access is granted. An LCD or buzzer shows feedback.

Components required

• Arduino Uno or Nano
• RFID reader module and tags
• 4x4 matrix keypad
• Servo motor or solenoid lock
• 16x2 LCD (optional)
• Buzzer and LEDs
• Power supply

Block diagram

Working

When a card is tapped, the RFID reader sends its ID to the Arduino, which compares it with a list of allowed IDs. If valid, the servo rotates to unlock the door and an LED or buzzer indicates success. The keypad allows entry by PIN. Multiple wrong attempts can trigger an alarm.

Applications

• Lab and office door access
• Locker and cabinet security
• Attendance and access logging
• Smart home entry control