- Looked into how the user interface would communicate with the Raspberry Pi. Studied the python interface web socket (https://websockets.readthedocs.io/en/stable/intro.html). Decided to keep the user interface local on the Raspberry Pi, and have it displayed to user through a touch screen (Pi Foundation Display – 7” touchscreen).
- Researched the rangefinder and load sensor. Decided on load cell amplifier hx711 and ultrasonic module hc-sr04 in the end.
- Looked into how the hardwares listed above could be connected to the Raspberry Pi. Added the items above to bill of material.
- Designed the user interface and made a scratch of the layout of the market.