This started out as a bit of a joke project but turned out to be surprisingly accurate at judging knocks.
Secret knock detecting door lock.
Hi all i ve done a bunch of modifications to steve hoefer s code for his secret knock detecting door lock.
Unlock the door with a secret knock.
If a piezo speaker hears the right number of.
A microphone okay really a speaker presses against the door and listens for knocks.
In the old movies a little sliding door would open so the doorman could check you out and let you in.
By default the knock is shave and a haircut but you can program it with anything up to 20 knocks long.
We use the arduino uno but any standard arduino is appropriate for this project.
If it hears the right number of knocks in the right cadence it triggers the motor to turn the deadbolt and unlock the door.
This is the changes that i ve made added a hall effect sensor to determine if the door is open or closed swapped the gear motor with a servo added a serial lcd feedback screen added a yellow led added a bunch of extra features.
Some examples are pir based security system rfid based security system digital lock system bio matrix systems electronics code lock.
Build this project at our next weekend long arduino workshop.
The secret door knocker uses a piezo element to record and detect your secret knock pattern then turns a servo motor that you can connect to your door lock.
Press the programming button and knock a new knock and it will now only open with your new knock.
Use your favorite song morse code whatever.
In this project i used an arduino uno a piezo speaker and a servo motor.
Press the button to record a knock pattern then test it by knocking.
Secret knock detecting door lock.
If the sequence isn t recognized the system resets and listens for knocks again.