Keyboards are great for making electronic music, but as Daniel of Switch & Lever points out in the video below, they may not have enough buttons and knobs to get the sound just how you like. To help fix this issue, he constructed his own custom MIDI input — theMIDInator — with a RC transmitter-style joystick, a variety of knobs and switches, and a numeric keypad that acts as the keyboard itself. No levers seem to be implemented as of now.
An Arduino Mega with its expanded IO capabilities accommodates the rather large number of inputs needed, and software including LoopMIDI and Hairless MIDI to Serial Bridge were used to get things working correctly. When finished, his device passes MIDI signals to a DAW, or digital audio workstation that produces the actual sounds from input data.
TheMIDInator's housing is beautifully made from laser-cut wood, which was glued up and finished, before Daniel attached the controls. While he tested the functionality of different parts individually with, he wired everything up in the enclosure itself before testing the overall system. This presented some advantages and disadvantages, and few swapped wires did have to be compensated for in software.
Code is available here, though the build is meant to be more of an inspiration than something you would follow step-by-step. Hopefully you’ll instead be motivated to create something suitable to your individual needs!