The background of this project

Each year, many people died for forgetting to bring their keys. most of these people lived in apartments, which they tried to climb up to their balcony and fell down to the ground. This project introduces an electronic doorbell that was connected to the apartment's access control system, opens the door by sending simple messages through messaging bots. In addition, this device was connected to a camera that captures an image of the person who was outside your door. This project is still under construction.

The programming languages I used

Python/Raspberry Pi, JavaScript, PHP

Theory

The hardware architecture of this project was based on Raspberry Pi Zero, which can easily replace existing doorbell devices due to its small size. The camera I used in this project is a Raspberry Pi camera module, it can also be replaced by an IR version that can take better images in darker environments. I have attached an IR transmitter that can open the door of my apartment. The access control system in my apartment supports opening the door downstairs using a controller. Once the Raspberry Pi receives a command, the Raspberry Pi will send a specific signal to open the door. However, this system was designed based on my condition, it does not apply to every apartments or homes. Additionally, the IR signal could be weak in higher floors/buildings, the interior design of the building could also effect the signal. In rare cases, the signal has to be send twice to open the door.
The controlling side I choose was LINE bot and Telegram bot that both runs a backend server to process data. Since these messaging applications are largely used by people daily, users do not have to install an additional application.

System architecture/Screenshots