Severin Teona - AAC2

teona.severin@stud.acs.upb.ro

The main idea behind this project is to have a smart video doorbell, whose camera is triggered by pressing a button. After the photo is taken, you get an e-mail (as a notification) to let you know somebody is at your door. In the e-mail you get a link to a simple HTTP server where you can see the photo. On the server there are also 2 buttons: one of them is used to open the door for the guest and greet him with a nice message using an LCD, and a button used just for sending a message that the owner is not home. If the first button is pressed, the door will also open. The main motivation for this project came actually from my parents: they have been asking me for the past year if I can build them a system like this, because at home, we don’t have any window facing the gate or the outside of the door. Furthermore, we don’t know if anyone enters our yard.

For this project, I used 2 ESP32 modules:

• ESP32 WROOM
• I2C HD44780 LCD
• SG90 servo
• ESP32-CAM module with SD Card
• CP2102 USB to Serial converter
• Button

This project contains 2 ESP32 modules, and is therefore divided in 2:

1. The first system is controlled by the ESP32-CAM module, which doesn’t have any power supply socket. Because of that, I used a CP2102 USB to Serial converter to power on the device and to also have access to its serial port. On this board I also connected a button on GPIO13 pin to trigger the photo being taken. With this module, I also had some problems: I managed to destroy the external flash memory chip and I had luck I managed to find someone to change it.
2. The second system uses the ESP32 WROOM module that controls a I2C LCD display that shows different messages and a SG90 servo motor that opens and closes the door. The servo motor is connected on the GPIO13 digital pin.

When it comes to software, I used Arduino IDE and the following libraries:

• ESP32-Wroom
  • WiFi.h - to connect to the internet
  • HTTPClient.h - to send HTTP requests
  • Arduino_JSON.h - to parse the response from the HTTP requests
  • Wire.h & LiquidTWI2. h - to communicate via I2C with the LCD display
• ESP32-Cam
  • esp_camera.h - the official library of the camera inside the module
  • WiFi.h - to connect to the internet
  • HTTPClient.h - to send HTTP requests
  • Arduino_JSON.h - to parse the response from the HTTP requests
  • FS.h & SD_MMC.h - to access the file system inside the SD card

The functionalities of both these modules are described in the following diagrams: