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Flexible Body Armor
dotmax writes "One item to pop out of the Turin Winter Olympics is the use of flexible body armor. Similar to silly putty, this shear rate material is flexible under normal load and hardens under impact. Sounds expensive, but could offer some great alternatives for traditional hard shelled impact gear in active sports and military applications."
Entrepreneur : (noun), French for "unemployed"
Since it only hardens on impact, could it also be used in hand weaponry?
"Honest, officer, we just came across him and he was beaten to a pulp. You can search us, go ahead, we ain't got nothin' but our gym towels..."
Village idiot in some extremely smart villages.
I might be impressed, but only if it uses a Holtzman Fields somehow....
*Disclaimer: May be exaggerated
The things that happen when struck by a bullet or shrapnel are different than a skier hitting the ground. This material could perhaps help to make the impact plates, but the actual stopping of the penetration will likely need "normal means"
Now when spies want to copy documents, they can just tear off a piece of their armor and press it against the pages.
In other news, 98% of women polled can't wait until they start making condoms out of this stuff.
But Phil Green, research director at d3o Labs, says it is difficult to precisely measure the material's properties because the hardening effect only last as long as the impact itself.
Certainly a researcher could take a sample of this material and strike it with increasing force using a material with known hardness. That might get them an answer beyond: "we don't know." I'm skeptical of this material's utility in a military application. Particularly as body armor against high velocity bullets and shrapnel. Woven carbon and Kevlar seem still unmatched in its capacity to take a high impact round. But, like I said, an assault riffle and a material sample could answer that question in minutes...
Sounds like gel suit armor. Let's hope you like your suits personality.
I do a lot of inline skating and I can see where this stuff could be revolutionary for outdoor inlining, skateboarding, etc.
Personally, I don't wear pads because they're uncomfortable. I do wear a helmet and palm sliders, which are supposed to help keep your palms from getting skinned up in an actual fall by serving as a buffer between your palms and the asphalt. In theory, they work pretty good. When you fall going upwards of 30MPH, they aren't a lot of help. Once you hit the ground, even if you initially brace with your palms, momentum is pretty much going to send you wherever it wants.
Being able to wear a long sleeved shirt or pants made of this stuff to help protect the knees and elbows would be huge. I have a road rash spot on my elbow now from a fall last weekend. Granted I don't fall much.. that was the first time in over a year I've had a crash and it was a very minor crash but even still, I'd probably wear this stuff for safety if it was available and not terribly bulky. Most inliners who are serious wear skin suits or jerseys so substituting this stuff would pretty much have no downsides as long as, like I said, it wasn't too bulky.
On the flip side, most skateboarders want to look "extreme" so this stuff might not be a huge hit with them. I personally like my skin intact, however.
Looks like they use a Non-Newtonian fluid, that's the type of material that has these properties.
This was one of the cooler demonstration in my HS chemistry class, the teacher made up a big batch of water + corn starch, and was playing with it like mud, squishing it around and whatnot. Then he beat the hell out of it, and it just sat there and didn't splash, it looked (and sounded) like it was a solid sheet. It was odd to see something that was very dynamic under low force, but static under high force.
It's like a seatbelt, if you yank it hard it locks up, but if you pull gently it will extend.
The original bullet-resistant vest was flexible. It was made of powdered glass, flexible until hit hard, at which point it would stiffen up and spread the force of the impact.
-russ
Don't piss off The Angry Economist
Having rigid plates even on parts of the body that flex less is bulky and cumbersome. Flexible armour is a great concept - far less noticable in normal conditions than some of the rigid ski body armour solutions e.g. Dainese
BTW For the pseudo science and some nice pictures of 'molecules' see the 3DO website
"Similar to silly putty"
If it were more like Flubber (if you remember this you are an old geek) the projectiles would bounce back at the source.
I lost my sig...
...and frankly, this flexible armor sounds great. The reason you want some kind of protection is that you (sometimes in speed events, very often in slalom) run into gates (the plastic poles stuck in the snow that you have to turn around) with various parts of your body. Since you are going fast, and you are wearing a thin aerodynamic racing suit, it hurts like hell. So, if you don't feel like getting hurt, you strap on some plastic shin and arm guards, sort of like an Ancient Greek warrior with his greaves. Anyway, these plastic guards really are not the ideal solution. They chafe (since you are strapping them on tight, and the muscles and skin under the straps are constantly moving). They limit your motions quite a bit. They are, frankly, uncomfortable. And if you are doing speed events, they kill your aerodynamics.
So, as far as I am concerned, flexible armor is totally the way to go. Hopefully FIS won't ban it.
I want to get all my underwear made out of this stuff. That way I'll never have to wear a cup for sports.
It would also help for when I want to be impertinent to feminists.
John Brunner's "Stand On Zanzibar", 1968 Hugo Award winner. The item was called "karatands". A soft glove-like material until hardening on impact.
This is a truly oustanding book that should be digested by geeks everywhere. The political and social points are even more relevant today that 30+ years ago.
I think people are getting the wrong impression here. This is put into suits for slalom and super G athletes. It's not to protect you from a fall, but to protect you from the flags that whip you when you go around them. It's not going to save you when you crash into a tree. It's going to stop you from getting bruises on your arms and legs when you hit the flags.
:-) )
Cool idea. But probably not particularly practical in other applications (maybe useful for kendo??? -- but the armour's way cool, so why change
For body armor purpses: .0004 (four ten-thousands) of an inch into me. In the same time the armor hardens in an circle with a radius of .0004in (For the sake of arguement a very thin bullet). In the next millionth of a second the bullet travels an additional .0004 of an inch into the target. The armor now also has a circle of .0008in in diameter. The affected area starts to grow rather quickly.
The material's reaction time is probably related to how fast the shock-wave of the hit travels through the material. For the sake of arguement: The of the impact shockwave travels through the suit at the same speed sounds travels in water (sound is a shockwave). So it travels roughly 1482 m/s. So the shockwave would take roughly 0.0001 seconds to travel across my entire chest. Modern bullets can travel roughly the same speeds. In that same 0.0001 seconds a bullet would be several inches behind me.
So here comes the messy part: Can this kind of stuff protect a person from gunfire?
So a bullet hits a person wearing this stuff. In the first 10^-6 of a second the bullet travels
Time Depth/Shockwave Area Affected
0.000050: 0.2000: 0.1256637061
0.000100: 0.4000: 0.5026548246
0.000150: 0.6000: 1.1309733553
0.000200: 0.8000: 2.0106192983
0.000250: 1.0000: 3.1415926536
0.000300: 1.2000: 4.5238934212
0.000350: 1.4000: 6.1575216010
0.000400: 1.6000: 8.0424771932
0.000450: 1.8000: 10.1787601976
In the time it takes the bullet to travel 1 inch into the body enough of the armor has hardened to cover 3 square inches of the target's body. Now the bullet has to deform or move that much more material in order to continue its trip in. Most likely the person could end up with a weird dent in their body where the bullet hit. This is of course dependant upon when the material fails and stops giving protection and how fast the shockwave travels through the material.
Considering that though: I'd rather have a dent in my body then a hole.
Currently the ski suits are used to protect against impacts against relatively flexible things at speeds above sixty miles per hour. So for the athletes to approve of it, it has to work pretty quickly and revert pretty quickly. You are in contact with gates for hundredths of a second and if the armor/fluid reacts fast enough for the athletes to notice and approve, you know the army is going to buy a suit and shoot at it to see what the results are going to be. Imagine the next round of (Disposable) ceramic armor plates that is sent to the troops in Iraq is coated in that stuff and it improves survivability.
Hell, coat the inside of the flak vests in the stuff and have it sent to the firing range for testing. The army always loves things that do the following: improved force protection with less weight. While the army is a giant monolithic beuracracy it does actually get things done once in a while.
Architectural plans are like computer source code with a couple of differences: You only compile once.
Kinda cool, but what is the point of scaleable soundproofing? If you want something to be soundproof, why would it need to ever increase or decrease sound proofability? Why not just make it as soundproof as possible from the start?
This just in! 3 out of 4 people make up 75% of the population.
Let us assume that you are about to be shot in the chest with a 12 gauge 3.5" super-magnum slug, which is overkill for anything short of a bear, or maybe a truck. Let's also assume that you have the option of either wearing the thinnest vest that will stop that slug or nothing at all.
If you wear the vest then when the slug hits it'll dump all it's energy into your chest. You'll sustain massive blunt trauma on the level of getting smacked with a sledgehammer. Lots of broken ribs, lots of bruising, possibly some organ damage and internal bleeding, if you're hit near the heart maybe death.
If you DON'T wear the vest then the slug enters the front of your chest, dumps part of it's energy into your tasty meats, exits your back, and continues on it's way into whatever was behind you. It breaks any ribs it hits near, creates a big ol' permanent cavity through whatever organs are in the way, and paints the wall behind you a lovely shade of red.
I don't know about you, but I think I'll take my chances with the vest TYVM. If I could get the vest lined with some of this stuff to help soak up some of the blow then even better.
It isn't primarily the hardness but the stiffness that prevents blunt impact injury in armor design. The impulse is distributed over a wide area so that the peak force is less than the threshold for bruising. Crumpling is used in secondary foam in helmets (which does not contact the wearer directly). In helmets, the outer shell, the resilient inner foam and the skull provide the force-spreading function. Crumpling is not relevant to armor design since the purpose is not to absorb the energy but to distribute it, and crumpling material would be far too bulky for ski armor anyway.
"Is life so dear, or peace so sweet, as to be purchased at the price of chains and slavery?" - Patrick Henry
These suits provide protective padding for RACERS so they don't suffer bruises or breaks when the hit the gates. These suits are NOT for crashes.
I am a competitive alpine ski racer. Watch the slalom (SL) events in the Olympics and you will see that every athlete wears hard protective equipment on his poles (to protect his hands), his shins, and usually on his head. This is because the tightest, shortest, fastest line down the course involves literally running over the gate. The athlete generally "cross-blocks" the gate, meaning his feet are on the correct side of the pole and angled outward, while his body is upright with the pole directly in his path; he simultaneously hits the gate with the protector on the front of his pole ("pole guards") and his shin guards. Furthermore, he's wearing a lycra speed suit that's got padding in several key areas including the front of the forearms, the back of the thighs, the deltoid area of the upper back, and the bicep area of the upper arm. This is to provide protection for when the athlete performs an "inside clear" instead of a cross-block, or if he loses his rhythm or something else that causes him to hit a gate where he's not wearing molded plastic armor.
Or you could have just read the article.
Intercarve Networks, LLC
Seriously, this stuff would be awesome for paintball armor.