A large matrix of launchers each shooting aerial daylight smoke fireworks (see link) that are precisely timed to blow up at a specific altitude.

They're all launched at once and as they reach the specific "pixel" point of their trajectory, they blow up, leave a puff of smoke an draw a 3D smoke sculpture of a rabbit or whatever.

I don't know if there's any fuse that's accurate enough to get the timing just right so you might have threads of various lengths that feed out th back as the rocket rises and pulls a pin to ignite the explosive when it gets to the right length.
-- doctorremulac3, Sep 05 2014

Using these things daylight_20fireworks
[doctorremulac3, Sep 05 2014]

Daylight fireworks show https://www.youtube...watch?v=FPV8zdiySlI
They make a nice rainbow. Seems to be essentially what you're after. [tatterdemalion, Sep 06 2014]

This is what it would look like http://raikoh-illus...a-unicorn-420791861
It would be 3d with highlights and shadows from the sun. [doctorremulac3, Sep 06 2014]

Or this http://www.labconco.../faces-in-the-cloud
But you could have different colors obviously [doctorremulac3, Sep 06 2014]

The timing is good enough to make a firework sphere. In theory the fuses could be altered at each direction allowing basic sculpturing of a sphere. So, I can imagine it would be possible.
-- wjt, Sep 05 2014


BTW, I guess you could use regular nightime firworks as well, it's just that the 3D creation would only last for a second. With the smoke you'd be able to look at it for a bit and you'd even get some shadows and such to enhance the 3d features.
-- doctorremulac3, Sep 05 2014


The timing is less of an issue than aerodynamics and air movement.
-- MechE, Sep 05 2014


Well, you'd need a completely windless day for starters.

Maybe a better way to it would be to just have one big bundle that shoots out all the "pixel explosions" in all directions from a central hub. Just launch a massive "bus" with all the secondary rockets aimed outwards.

Then you'd us the trailing wire actuated detonators. With this you could get pretty precise.
-- doctorremulac3, Sep 05 2014


You don't use rockets; you use mortar shells (q.v.).

Disney use compressed-air launching from fixed tubes.

Precise - very precise - timing fuse trains are possible, and have been for more than a century; but that precision comes at a high price.

This is entirely possible, but has never been done in a civil application simply because of the cost.
-- 8th of 7, Sep 05 2014


Disney could afford it. Imagine a 20 story mouse head exploding in the sky. Sounds like the lyrics to a Jimi Hendrix song.

Hey, wait a second, forget the fuses. You ignite they remotely all at once. You LAUNCH them at different times.

Much easier.
-- doctorremulac3, Sep 05 2014


They make 3d renditions of objects in the sky? Please post link.

Also please post info about this "very complex control systems to position the 'pixels'" you've referred to.

When you're done posting links showing somebody has already thought of painting bands of different chemicals on a candle wick to make the flame change colors.
-- doctorremulac3, Sep 06 2014


// Well, you'd need a completely windless day for starters.

No not completely windless. You'd want some breeze to clear the screen, so to speak. Otherwise you'll just have a cloud of smoke form.

Added a link, all sorts of colored and black smoke images are produced.

edit: I see [bigsleep] posted simultaneously to mine.
-- tatterdemalion, Sep 06 2014


Those are 2d. I haven't adequately described what it would look like. See link.
-- doctorremulac3, Sep 06 2014


I remember watching a fireworks "tree" in Japan - it started out small, then subsequent flashes would light up the smoke from prior explosions - yellowish flashes lighting up the brown "trunk" of the tree, higher up green flashes to light the foliage. It took probably 40 seconds overall to "grow" the tree to its full height, then they managed to give it red&white blossoms all over the outside of the canopy. Very organic, and didn't require super-precise control, but still very effective. (Kochi River, summer of 1982)
-- lurch, Sep 07 2014



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