Ballast Control

Having a rough excess 10kg lift, this left an opportunity to implement a ballast control by placing 4 plastic container with valves in each corner of gondola, something like this:

Lid to be attached to the gondola’s platform, carrying normally-closed air valve (solenoid) through a spacer on its top. Lid’s clamps to be used to attach container to the top. A ballast (water) release valve to be located at the bottom of the ballast tank. Being always open it will rely on the solenoid to open to let the air in to release water.

Valve design:

use <ShortCuts.scad>
use <blimp_parts.scad>

$fn=100;

module body() {
D() {
T(7,1,5)
Ry(90)
R(0,-90,90)
minkowski() {
scale([2,1,1])
cylinder(r=7.5, h=0.01, $fn=3);
sphere(10);
}

T(10,-24,0)
cube(50, center=true);
}

Ty(5)
Rx(90)
minkowski() {
cube([0.01,10,3]);
cylinder(3,5,5);
}
}

module inner_tubes_cutout() {
hull() {
sphere(4);
cylinder(10, 4, 4);
Tz(10)
sphere(4);

T(0,6,5)
sphere(4);
}

T(0,6,5)
Ry(90)
cylinder(20, 4, 4);

T(20,6,5)
sphere(4);

T(20,16,5)
Rx(90)
cylinder(10, 4, 4);
}

D() {
%body();
inner_tubes_cutout();
}

Started with ordering 4 Mini Electric Solenoid Valve DC 6V/12V/24V Normally Closed N/C Water Air Flow Controllor Automatic Control For Flowers Watering from Aliexpress.

Together with 365+ Food container with lid, rectangular/plastic 4.2l from Ikea.

And a DC 4-Channel 443MHz Wireless RF Remote Control Relay Switch With 2 Receiver New from eBay.

All started arriving swiftly, while all the printing took a while.

Assembly itself.

This was a moment when we did a first test.

Next stage was to mount everything on a gondola and do some testing there.

At that stage I’ve started being bit afraid about whether our traverse tubes will be able to withstand all that weight again so did another test whole structure “flying”, while carrying full intended ballast weight + batteries.