DESCRIPTION
If you own several badges, cards, or tickets and would like to automatically publish the number of unused badges on the web in real-time, there is no off-the-shelf solution. However, with 3D printing, the AVR-IoT Cellular Mini board, APDS9930 proximity sensors, and a bit of Arduino programming, one can come up with a robust and secure solution. Although it does not sound overly complex, I still had to spend a few working days with 3D design, making myself familiar with the board, and come up with the necessary set of scripts and sketches.
DETAILS
You find all the details in the GitHub: https://github.com/felias-fogg/cardRack
COMPONENTS
1 × AVR-IoT Cellular Mini Board
3 × ADPS9930 proximity sensor breakout boards
1 × LED 3mm
1 × Resistor 470 Ω
1 × FeatherWing Doubler
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