Smart Bluetooth Baking Scale

Why?

  My mom loves to bake, and she spends a lot of time making sourdough and other precise recipes that require specific weights of ingredients. I noticed that her recipe books were slowly getting covered in dough. She hates having to turn the pages with messy hands, so I decided to digitize some of her recipes. Unfortunately, this didn't solve her issue; she still needed to use a mouse or trackpad and a keyboard with messy hands. To fix this issue, I built a small scale and coded an app which connected to the scale with bluetooth. I added a few recipes to the app, which automatically gives her instructions and advances when she adds the correct weight of the needed ingredient.

What?

• XIAO Esp32c3

• Load Cell (1-5kg)

• Load Cell Amplifier

How?

  The load cell can detect force, but can't send it to the microcontroller in a format it will understand. For the microcontroller to be able to find how much weight the load cell is bearing, we need the load cell amplifier to act as a middleman. I connected the load cell to the load cell amplifier, and connected the amplifier to one of the analog GPIOs on the MCU. From there, I ran a code on the MCU that detects how much weight (in grams) is placed on the load cell. Ten times a second, it sends that weight via a bluetooth packet to whatever computer it's paired with. On my mom's computer, I ran a Python program which detects the device's connection and accepts the bluetooth packets. The program has a recipe loaded via a JSON file, and it goes through the recipe in steps, moving on when she adds the correct weight of that step's ingredient.