So the model is a cylinder with spikes sticking out of it corresponding to the notes that are in the song. If I programmed the same note into the model 4 times, say 4 half notes one after the other, there would be 4 spikes in a line on the cylinder. When the cylinder rotates, the spikes will move. If I place a set of teeth that, when one is plucked, a note is played, so that it is up against the cylinder, then when these spikes move into a tooth, they will pluck it.
I am planning on hooking the motor up to the cylinder, so that the cylinder gets rotated.
The rpm of the motor needs to be regulated, because the speed of rotation of the cylinder will determine the speed at which the song I've programmed onto it is played.