see link about the Samurai Horo cloak.

This one would be held in place with a lightweight collapsible structure or kept open with a fan
-- pashute, Oct 12 2014

horo https://www.youtube...watch?v=8B_6BU7SYf8
[pashute, Oct 12 2014]

Spaced Armor http://en.wikipedia.../wiki/Spaced_armour
[MechE, Oct 14 2014]

Slat Armour http://en.wikipedia.org/wiki/Slat_armor
Similar to Spaced Armour, but more akin to the horo - could additionally be wrapped in silk, nylon or other material. [zen_tom, Oct 15 2014]

AND Zip tie armor for the spear carriers and camp followers ?
-- popbottle, Oct 12 2014


My inflatable flailing tube army should be unstoppable.
-- 2 fries shy of a happy meal, Oct 13 2014


Isn't this essentially the theory behind spaced tank armor? The one that is designed to prevent shaped charges or HEAT type rounds from penetrating the main armor?

However, since an anti-tank round is quite a bit heavier than armor, it needs a bit more than a layer of silk, to provide the extra barrier.
-- MechE, Oct 14 2014


According to the "horo" video and to a mythbusters episode that I was not able to find and link to, but have seen some years ago, the flexible silk is able to deflect and diffuse the kinetic energy along its "web" in the end even stopping bullets at full speed.
-- pashute, Oct 14 2014


I doubt very much that a horo would stop a bullet.

The horo works by a very subtle combination of yield and resistance. When hit by an arrow, it moves quite a bit, but its movement is resisted by the air. Because of this, it provides a moderate stopping force over quite a long (a few tens of cm) distance, absorbing a lot of the arrow's kinetic energy.

If it's hit by a bullet, the velocity means that the horo will not move very much (ie, air resistance will be much too high at bullet velocities) - it will behave very much as if were stretched taut over a rigid frame. Consequently, the bullet will go through the horo without significantly moving it, and without itself being slowed significantly.
-- MaxwellBuchanan, Oct 14 2014


so Kevlar.
-- FlyingToaster, Oct 14 2014


A great big Kevlar Zorb around the tank.
-- RayfordSteele, Oct 14 2014


A very fine net, much coarser weave than silk, made out of CNT. The bigger holes should mean very much less air resistance... or inertia actually... it needs to stand up to being able to accelerate up to bullet speed very fast.

I wouldn't begin to know how to calculate the acceleration forces in such a system.
-- bs0u0155, Oct 15 2014


You still need a good amount of inertia for it to work.

Consider: the bullet hits the net at (say) 500m/s. You want it to be decelerated by at least 50% (say) before it makes contact with you. The distance over which it can be decelerated (between the horo and your torso) is, say, 10cm.

The gives the horo about 0.3ms in which to decelerate the bullet by 250m/s - that's a deceleration of roughly 1 million m/s/s. Assuming that the bullet has a mass of 20 grams, that means that the horo has to apply a force of about 20,000 Newtons (about a tonne) throughout that 0.3ms.
-- MaxwellBuchanan, Oct 16 2014


[MBs] conclusions are reasonable.

An arrow has approximately an order of magnitude less velocity than a bullet, despite the bullet weighing around half as much. Therefore KE is approximately 50x less, and the horo doesn't have to do anywhere near as much work against the arrow.

And please note this is being generous on the arrow velocity (basing it on a modern compound with lightweight arrows). You go to a wooden straight bow, traditional arrows (as shown in the video) and you're probably looking at a much wider difference, since the bow designs are lower speed, and the heavier arrows will produce a lower velocity anyway.
-- MechE, Oct 16 2014


//[MBs] conclusions are reasonable. //

That is probably the first time in the history of the universe that that sentence has been written in earnest.
-- MaxwellBuchanan, Oct 16 2014


I think this was a device of its own time only...back in those days, talking about muskets. So, lower velocity and wider cross-sections, not to be mention being blunt.

I do seem to remember silk armour working on musket balls, if the silk was very tightly wrapped around the body, as it turned the direction of force from the usual A to B (with A being the musket barrel, and B being somewhere in the back of the torso) to something like 90 degrees to the path A->B.

Not enough fool-proof, and would have hurt like hell to get shot though.
-- not_morrison_rm, Oct 16 2014


Hearsay, no actual historical source, is that silk was popular for protection against arrows, especially war points (barbed). It wouldn't prevent the wounds, but since the silk didn't tear, it wrapped around the head and allowed it to pull right back out.

As far as the tight wrapped silk, I could see it providing some protection, but you're still going to feel the entire force, it's just going to spread over a bit larger area. Musket balls still had a lot of KE, so it probably wouldn't work at close range, but it might have helped against longer shots, or richochets or such.
-- MechE, Oct 17 2014



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