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crushingly good origami

Use pressure vessel collapse to fold undersea sculptures.
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Use a deep learning algorithm to build an energy vector plan of the designed origami fold. This plan gives metrics on pressure and method of scoring of the origami metal sheet.

The pressure metrics will translate to a welding plan of various sealed vessels* at different places on sheet which can crush at different depths. This crush change will deform sheet around scored lines.

This sheet can the be dropped overboard at a position with suitable depth. Sort of like protein folding, the sculpture will transform itself on the way down and come to rest at it's ocean bottom installation gallery. Life, down there, now has a new artistic entity and stimulus to evolve and adapt as they see fit.

Art can now give a neutransmitter difference,hopefully pleasurable, to passing echo-locating whales.

* Some complex folds may need contact explosive.

wjt, Apr 11 2020

Just so depressed... no, inpressed. https://www.youtube...watch?v=Zz95_VvTxZM
[2 fries shy of a happy meal, Apr 12 2020]

Nuclear Isomer https://en.wikipedi...wiki/Nuclear_isomer
We use these a lot, particularly for portable storage of energy. [8th of 7, Apr 14 2020]

[link]






       //Some complex folds may need contact explosive//
If you're careful, you could get the (internal) air to flow from a collapsing section into another, to stiffen it a bit. Internal ribs/structures would also allow collapsing bits to "push" on other bits.
(Coincidentally, I was just watching a YouTube video about engineering applications of origami this morning...)
neutrinos_shadow, Apr 12 2020
  

       Funny... I was watching this [link] this morning.   

       //Some complex folds may need contact explosive//   

       We will pay a dollar to watch you create complex folds with explosives.   

       No, actually, make that two dollars. Cash money, in advance. Used, unmarked bills, or coin - you choose.
8th of 7, Apr 12 2020
  

       Scaling down a building collapse might have some problems but not insurmountable.
wjt, Apr 13 2020
  

       There is a lot of difference between shattering masonry, which is brittle, and controlled plastic deformation of a metal, which may require explosive lensing. You need a non-isotropic shock wave and moderate brisance. EFPs will merely blow holes in your workpiece. Tamping will cause undesirable edge effects....   

       All right, three dollars, but that's our final offer. And we get to take some of the bits as souvenirs.
8th of 7, Apr 13 2020
  

       1mg is not explode the same as a 1g or 1kg is it?
wjt, Apr 13 2020
  

       No. The effects are markedly non-linear, and geometry is crucial.   

       The mechanics of initiating a 1g charge are formidable. You need a supersonic shock wave, which in turn needs a primary explosive - an azide is typically used. That has to be triggered by a low-yield pyrotechnic. There are mechanical limits on how small such a device can be made and still function reliably; having something that isn't highly reliable is a Very Bad Thing. So even before you have detonation, you have already released a substantial (relative to the size of the assembly) and intense (over a very short range) shockwave.   

       Three dollars. Last offer.
8th of 7, Apr 13 2020
  

       So reducing, amount explosive is limited by our technological smarts to initiate the reaction. Ah, the need of a quantum shockwave to fold a molecule such that it generates it's shockwave. Very catch-22.
wjt, Apr 14 2020
  

       Quantum effects aren't so marked at the molecular level; they are more restricted to the nucleonic and sub-nucleonic phenomena.   

       Electrons behave probabalistically - full-size molecules, not so much. Chemical explosives function at a molecular level. Sounds like what you want is a nuclear isomer <link> to produce the initial high energy-density.
8th of 7, Apr 14 2020
  

       Still not a push button cascade to outcome, the weak force being pretty probabilistic in the face of anything humans do currently.   

       With intermolecular distances, can one molecule of the explosive breaking at the right pair of electrons, set off the rest?
wjt, Apr 17 2020
  

       The probability is vanishingly small.   

       Detonation is a bulk mechanical effect requiring a supersonic shockwave. That's easier to achieve in a primary, but primary explosives are too sensetive to risk handling in bulk (more than gram quantities). Even then the detonation cascade is started by a thermal mechanism- deflagration- in the bulk material.   

       If such systems were capable of being triggered by a single-molecule event, and some are, they would be so unstable as to be unusable in practice. One cosmic ray strike could set off the lot.   

       Such materials do exist, but are rarely manufactured for other than experimental reasons, and even then only in tiny quantities, usually outdoors on the other side of a rampart of sandbags.
8th of 7, Apr 17 2020
  

       Though, if what happens under a supersonic shockwave could be actioned into a single scaled energetic analogue, would the energy coming from that one molecule detonation initiate it's neighbours in going supersonic? The explosive could then, in theory, be one molecule to any number of moles wanted, But there would still be a limit to the number of molecules before supersonic is transcended. I am not imagining a one molecule bust to be supersonic or am I wrong?
wjt, Apr 20 2020
  

       <sigh/>   

       A single molecular disintegration is inherently "supersonic" but you need to factor in mean free path in a solid (i.e. zero) and the problem that the motion of a single fragment will be shared amongst all the molecules around it.   

       The momentum needs to be sufficient not merely to accelerate those molecules but add sufficient energy to take them above the threshold for triggering further decomposition.   

       Thermal energy can do this in a primary explosive. That's why they're so dangerous- they're perilously close to the trigger level even at ambient, so a small mechanical shock can start the cascade. It's not like a nuclear chain reaction which is dependant on fission cross-section and the proportion of fissile isotopes and not much else.   

       Warming a primary explosive brings the bulk material closer to the point of critical instability. That's why it says "Store in a cool place" in big, jarring, unfriendly letters on the box. The more energy present as heat, the smaller the additional energy needed to trigger the reaction.   

       There's a lot of useful information out there if you care to go away and read it ...
8th of 7, Apr 20 2020
  

       Just one more annoyance*. The disintegration is space vectored or not in a perfect sphere, right?, the group of atoms give a supersonic push in one direction, some atoms in others. Placing the explosive molecules, if it was possible, in an ordered pattern of orientations would get you a bigger bang and a shaped supersonic wave. Iterating again, if this thought was possible**.   

       * You know that's not going to be true. **if a system was capable of engineering a single 'stable' explosive molecule's detonation.
wjt, Apr 22 2020
  

       Monocrystalline polynitrated arlys like RDX and particularly HMX have been produced for some decades, essentially by the same crystal-pulling techniques from melt used for silicon boules. Sandia labs (q.v.) are amongst the leaders in the technology.   

       They display markedly different propagation rates along different crystal axes, and indeed if initiated "off-axis" the detonation will tend to re-align and "follow" a crystal plane. This is Very Useful. But such crystals are, unfortunately, very expensive to produce in bulk.   

       You're right in that the initial impulse isn't isotropic, but can for most practical purposes be considered a point source. Read up on bridgewire detonators.
8th of 7, Apr 22 2020
  
      
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