Create a 150kg Scale Connected to Google Firebase

Today we will hack an IKEA Saltviken bathroom scale and create a connected weight sensor for up to 150 kg. We will use Googles free No- SQL Firebase cloud service as a data storage. To do that, we have to tear this nice scale apart and have a look inside.

We will:

- Re-use the load cells of the IKEA scale to measure heavy loads up to 150 kg or another scale.

- Replace the original PCB with an HX711 and an ESP32 (should also work on ESP8266).

- Learn from IKEA how to wire the four special load cells that they add the weight.

- Transfer data to the new No-SQL database “Firebase” provided by Google.

- Calibrate the scale.

A load cell (or loadcell) is a transducer which converts force into a measurable electrical output.

Although there are many varieties of lsensors, strain gage load cells are the most commonly used type.

Links:

Sketch and connections: https://github.com/SensorsIot/Weight-Sensors

Firebase Library: https://github.com/ioxhop/IOXhop_FirebaseESP32

Info:

HX711: ForceFlex/HX711

How to wire 3 wire Load Cells: https://electronics.stackexchange.com

Load Cells: https://www.bosche.eu

Install ArduinoJson:

https://arduinojson.org/v6/doc/installation/

Belangrijk:

https://github.com/espressif/arduino-esp32/blob/master/docs/arduino-ide/mac.md

mkdir -p ~/Documents/Arduino/hardware/espressif && \
cd ~/Documents/Arduino/hardware/espressif && \
git clone https://github.com/espressif/arduino-esp32.git esp32 && \
cd esp32 && \
git submodule update --init --recursive && \
cd tools && \
python get.py

Installation instructions using Arduino IDE Boards Manager

==========================================================

Stable release link: https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json

Development release link: https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_dev_index.json

Starting with 1.6.4, Arduino allows installation of third-party platform packages using Boards Manager. We have packages available for Windows, Mac OS, and Linux (32, 64 bit and ARM).

Install the current upstream Arduino IDE at the 1.8 level or later. The current version is at the Arduino website.

Start Arduino and open Preferences window.

Enter one of the release links above into Additional Board Manager URLs field. You can add multiple URLs, separating them with commas.

Open Boards Manager from Tools > Board menu and install esp32 platform (and don't forget to select your ESP32 board from Tools > Board menu after installation).

Ook belangrijk:

https://www.seeedstudio.com/blog/2019/11/26/10-things-you-can-do-with-your-hx711-and-load-cell/

https://platformio.org/

https://github.com/bogde/HX711

https://github.com/me-no-dev/ESPAsyncWebServer

https://www.brainy-bits.com/load-cell-and-hx711-with-arduino/

https://www.amazon.de/dp/B07TVD1LM4/ref=sr_1_48?keywords=hx711&linkCode=w14&linkID=CFRGG5BGKGQJ62W2&qid=1582385460&sr=8-48