Embedded Lab

This fingerprint lock is described in an Instructable posted by JetLab and is about building an Arduino-based electronic door lock that can be installed on almost any access point in your house. The project uses a keypad and fingerprint scanner to grant access to the users by controlling an electric door strike with a relay.

I started this project because I was wanted to work with a keypad and fingerprint sensor as well as become more familiar working with LCD’s, I also needed a way to lock my door from the outside so I thought an electronic door-lock would be a great opportunity to over-engineer something and learn some cool stuff.

On power up the device displays a message on the LCD and a red status led lights up, indicating that the door is locked. The user then has the option of pressing a button for entering the password or for changing the password. To change the password the user would need to know the current/default password. If the password is input incorrectly then the display will show that the code was invalid and then revert to the default screen. When the code is entered correctly,the fingerprint scanner activates. If the scanner recognizes a fingerprint that has been enrolled then it will activate the relay and the a green status led for a few seconds, enough to open the door, enter and close it.