I recently had to build an infrared close proximity sensor that could tell if something was dropped in a parcel delivery drop box. After some searching, I ended up using a microcontroller and a piece ...

Posted in Arduino Hacks Tagged A4988, arduino, dispenser, ir sensor, label, NEMA-17, stepper motor, sticker ...

[Jordan’s] sensor includes just a single pixel. The sensor is really just an infrared photodiode inside of a tube. The diode is connected to an analog input pin on an Arduino.