Otp Doorlock with Arduino

Hi everybody, here's my new Arduino project a door lock you can open with an OTP code that is a sequence of 6 numbers generated by a mobile app and working for only 30 seconds Here's a simple demo to show how it works First, an Arduino Uno... ... connected to a numeric keypad and to a servo motor that opens the door First, you need to sync the Google Authenticator app with the same secret of the Arduino sketch You can use a webpage I created for that Type the name of the new account (for example "door") then the password you want to use the page displays the byte array for the Arduino sketch the password in base32 coding for configuring the Google Authenticator app and - even simpler - a QRCode Simply launch the application choose "scan a barcode" As you can see the app is automatically configured and it's already generating OTP codes Let's now check if it works... Insert the code displayed on the smartphone and the door opens! WIth the * button I can close it If I type a wrong code nothing happens...