There's a lot of smart lock solutions available on the market which allows you to control a door lock and report its status. However, it's been pretty difficult to find a solution that only checks whether the lock is in place or not.
This is why I've decided to build one myself in a way that:
1. It is non-destructive: I don't want to have to drill a hole in the door frame for both aesthetic and insurance reasons.
2. It uses the current lock as it is without any modification
Therefore I'm aiming to use an inductive sensor able to check if the lock is in place or not, through the wooden frame of the door. This sensor is connected to a relay and then to an arduino which will record the status of the door.
The current code doesn't record any door activity history but simply check on a regular basis what is the status of the lock.
The only one working in a reliable manner is the AI007. This is not only because of the bigger range but also because it is less sensitive to the metal plate on the side of the door frame which caused interferences with the Omron one.
The best solution would be to use a shielded sensor but I've not been able to find one with such range or are way too expensive.