//Steampunk style microcontroller controlled physical music instrument.
//Organ pipe part:
SPEED_OF_SOUND_IN_AIR_20C = 343.2;
function waveLengthInmmFromFreq(frequency, closed) = (1000.0 * SPEED_OF_SOUND_IN_AIR_20C / frequency) * (closed ? 0.5 : 1.0);
module organPipe(frequency = 880, diameter=50, closed=true, fanSide=80, fanThickness=20) {
wavelength = waveLengthInmmFromFreq(frequency, closed);
sideWall = 3;
endWall = 5;
radius = diameter * 0.5;
startLen = 50;
windPipeRadius = 10;
windPipeLen = 10;
fanRadius = fanSide * 0.5;
fanAdapterLen = fanRadius;
difference() {
union() {
// Pipe
translate([0,0,fanThickness + fanAdapterLen + windPipeLen + startLen])
cylinder(h = wavelength + endWall, r = radius + sideWall);
// Start section
translate([0,0,fanThickness + fanAdapterLen + windPipeLen])
cylinder(h = startLen, r1 = windPipeRadius + sideWall, r2 = radius + sideWall);
// Wind section
translate([0,0,fanThickness + fanAdapterLen])
cylinder(h = windPipeLen, r1 = windPipeRadius + sideWall, r2 = windPipeRadius + sideWall);
// Fan adapter
translate([0,0,fanThickness])
cylinder(h = fanAdapterLen, r1 = fanRadius + sideWall, r2 = windPipeRadius + sideWall);
}
// Pipe cavity
translate([0,0,fanThickness + fanAdapterLen + windPipeLen + startLen])
cylinder(h = wavelength, r = radius);
// Start section cavity
translate([0,0,fanThickness + fanAdapterLen + windPipeLen])
cylinder(h = startLen, r1 = windPipeRadius, r2 = radius);
// Wind section
translate([0,0,fanThickness + fanAdapterLen])
cylinder(h = windPipeLen, r1 = windPipeRadius, r2 = windPipeRadius);
// Fan adapter
translate([0,0,fanThickness - 1])
cylinder(h = fanAdapterLen + 1, r1 = fanRadius, r2 = windPipeRadius);
}
}
organPipe(440*4, 50, true);
