Door Lock System with Graphical Password

This project of an embedded door lock system is described with a digital lock interfaced with a microcontroller. The principle aim of this door lock system is to enable a door with a graphical password or a fingerprint. The user will be able to enter a graphical password on touchscreen, or use finger on a fingerprint sensor, to unlock the door. The user will also be able to add or delete a stored password/fingerprint entry with the help of touch screen UI. For security purpose, the system will display information of the key used for last unlock action. The user will know if someone else has entered the room when the user was absent.

The system diagram is shown above. The central finite state machine is responsible for state transitions and touchscreen display update. Graphical passwords are saved in EEPROM of Arduino module. The ROM is used to store passwords for user identity verification. The state machine also communicates with other devices for inputs and outputs. The touchscreen is the interface for the user to interact with the system. Fingerprints are saved in the built-in flash memory component of the fingerprint sensor module. The system uses a servo motor to simulate lock and unlock action on a door.

Hardware list:

• Arduino Uno R3
• 2.8" TFT Touch Screen
• SpringRC Micro Analog Servo Motor
• Optical Fingerprint Reader

Wiring schematic:

Libraries:

• Arduino Uno: EEPROM.h, standard libraries
• Touchscreen: Adafruit_TFTLCD.h, Adafruit_TouchScreen.h
• FIngerprint Sensor: Adafruit_Fingerprint.h
• Servo Motor: Servo.h

Central FSM States:

VisitorLcked: door locked

PWEnter: interface for entering graphical password

BioEnter: interface for entering fingerprint

DoorUnlocked: door unlocked, unlock history information

VisitorUnlcked: door open, user identify not verified

OwnerVerify: door open, verify identity to manage keys

KeyManager: door open, identity verified, manage keys

PWManager: manage password entries

BioManager: manage fingerprint entries

KeyDelete: confirm deleting action

Touchscreen project:Adafruit 2.8" TFT Touchscreen

Fingerprint sensor project:Arduino Fingerprint Sensor

Servo motor project:Arduino Fingerprint Sensor

Future improvements:

• Code optimization: currently takes 93% program storage, 71% dynamic memory
• Improve user interface: re-arrange text locations and add more instructions for the user
• External clock: get a clock module to keep track of timestamp for better unlock history display
• Key entries: could increase the number of key entries if needed
• Servo motor noise: in bio manager state, when the fingerprint sensor is sampling data, servo motor experience little fluctuations

Yuhao Feng:

• System overview
• Central FSM implementation
• EEPROM module
• System debugging
• Final presentation
• System demo
• Project website

Ruixiao Bai:

• Prior work search
• Fingerprint sensor module
• Servo module
• Push buttons
• Midpoint presentation
• System debugging
• System demo
• Project website

Project repository: repository

Final presentation video: final presentation

Project demo: project demo

EEPROM.h: https://www.arduino.cc/en/Reference/EEPROM

Adafruit_TFTLCD.h: https://github.com/adafruit/TFTLCD-Library

Adafruit_TouchScreen.h: https://github.com/adafruit/Adafruit_TouchScreen

Adafruit_Fingerprint.h: https://github.com/adafruit/Adafruit-Fingerprint-Sensor-Library

Servo.h: https://www.arduino.cc/reference/en/libraries/servo/