In project author Erientes’ country there have been a string of robberies, normally targeted at elderly people. In these nefarious acts, the perpetrators convince their victims that they are, in fact, caregivers of some sort in order to gain access to a home. Naturally, this made Erientes quite upset, but rather than just going about his day — or complaining — he decided to actually do something about this problem, designing a Raspberry Pi-based doorbell that uses facial recognition to detect if someone is friend or foe.
Hardware-wise, the device is fairly straightforward, with a doorbell on the outside to start the process and three large light-up arcade buttons as a user interface. When the visitor presses the doorbell, a Raspberry Pi Camera takes a picture, identifying the face as being on a whitelist, blacklist, neither, or both. Depending on the threat level, the green button lights up green for “safe,” yellow for “unknown,” or red for “definitely don’t open the door.” In addition, it’s able to send suspicious photos to a caretaker or relative over Telegram for an extra layer of security.
The system runs on a Raspberry Pi, and while it can work on a 3B and 4, a Jetson Nano would provide for better performance. Software is installed via Docker, simplifying setup, and code for the build is available on GitHub. The project was written with the intention that beginners could recreate it, hopefully helping keep the homes of these most vulnerable secure.