The making of: My smart doorknob

How I made it

Pardon the dirty table
The complete Micro:Bit code

The Bluetooth UART service allows another device such as a smartphone to exchange any data it wants to with the micro:bit, in small chunks which are intended to be joined together.


The basic internals of a doorknob
The result of attempting to drill the gears.
A wooden popsicle stick next to a joined spindle and potetiometer with a wooden spline

Side note: I also experimented with some scrap metals, salvaged from a USB connector, however it was too difficult to work with, and I couldn’t get it to be the right dimensions I wanted.

Final Assembly



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