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 ...
Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. You’ve probably seen them—sensors watching from the corners of ...
An Arduino can be used to test the life of any battery with less than 5 volts, Boxall says. So, for a quick way to see how much juice your AAA, AA, C, or D batteries have left, build this ...