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The Orange Goo Used In Everything From Armor To Football Helmets (cnn.com)

dryriver writes: CNN has a story about a slimy, gooey orange gel developed by British company D3O as far back as 1999 that is very soft and fluid-like normally, but that hardens immediately when it receives an impact: It's a gel that acts as both a liquid and a solid. When handled slowly the goo is soft and flexible but the moment it receives an impact, it hardens. It's all thanks to the gel's shock-absorbing properties... Felicity Boyce, a material developer at D3O, told CNN, "if you hit it with great force, it behaves more like a solid that's absorbing the shock and none of that impact goes through my hand."

American football has become a huge market for the British company, where the gel is incorporated in padding and helmets to absorb the impact of any hits a player receives. D3O claims it can reduce blunt impact by 53% compared to materials like foam. The material can also be put inside running shoes to improve performance and reduce the risk of foot injury. Usain Bolt ran with D3O gel insoles in his shoes at the 2016 Rio Olympics.

The material is being tested in body armor. "While we don't have a material that can stop a bullet, we do have a material that can reduce the amount of trauma that your body would experience if you got shot." There are also soft smartphone casings using the gel that harden when the phone is dropped and hits a hard surface.

96 comments

  1. Troll, Plus Infininity (Insightful) by Anonymous Coward · · Score: 0

    > a slimy, gooey orange gel

    Cue the Trump jokes.

    1. Re:Troll, Plus Infininity (Insightful) by Anonymous Coward · · Score: 0

      > very soft and fluid-like normally, but that hardens immediately when it receives an impact

      Now what is Melania using if these guys got hold of it?

      Kicking him in the nuts is now useless.

  2. SubjectIsSubject by p0p0 · · Score: 5, Insightful

    "British company mixes cornstarch and water, makes billions."

    1. Re:SubjectIsSubject by Anonymous Coward · · Score: 0

      And SpongeBob already invented it. A lolsquid.

    2. Re:SubjectIsSubject by Hal_Porter · · Score: 5, Informative

      It's a non Newtonian fluid, but it's not cornstarch

      https://en.wikipedia.org/wiki/...

      There's a video here

      http://www.telegraph.co.uk/fin...

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
    3. Re:SubjectIsSubject by Anonymous Coward · · Score: 0

      Bu Bu Bu But They used a COMPUTER! Instant Patent Double Plus Good!

      Oops, by referencing cornstarch, corn and water in this post, I've violated the rights of those who hold patents on water and those who hold copyright on corn.

      For such blatant sedition, my obligation is to shoot myself with my own bullet in a last ditch patriotic effort to save valuable tax dollars.

    4. Re:SubjectIsSubject by Anonymous Coward · · Score: 1

      It's not cornstarch, it's silly putty

    5. Re:SubjectIsSubject by Anonymous Coward · · Score: 0

      FUUUUUUUUUUCK

    6. Re: SubjectIsSubject by c6gunner · · Score: 1

      Dslow, soft bump. Drive fast, hard bump.

      So, just like a normal speed bump, then?

    7. Re: SubjectIsSubject by Anonymous Coward · · Score: 0

      Not quite. Just different strokes for different folks.

    8. Re:SubjectIsSubject by Anonymous Coward · · Score: 0

      Am I still supposed to think "football player" after seeing that video, Chris?

    9. Re: SubjectIsSubject by wonkey_monkey · · Score: 1

      Yes, only this one can get easily vandalised and will cost much more to replace.

      --
      systemd is Roko's Basilisk.
    10. Re:SubjectIsSubject by Anonymous Coward · · Score: 0

      I want some too!

  3. Rugby players don't wear high tech helmets by Hal_Porter · · Score: 4, Funny

    Now as an American you'll say "Don't they all get terrible brain damage?"

    And the answer is "Yes, of course they all do. Have you met any rugby players?"

    --
    echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
    1. Re:Rugby players don't wear high tech helmets by DontBeAMoran · · Score: 3, Funny

      buddy Hey, rugyb palyer I was.

      --
      #DeleteFacebook
    2. Re:Rugby players don't wear high tech helmets by Anonymous Coward · · Score: 0

      dun gor was me too, dawz i playd wit you on duh field wit da ball?

    3. Re:Rugby players don't wear high tech helmets by DontBeAMoran · · Score: 1

      He said brain damage, not writing like a teenager.

      --
      #DeleteFacebook
    4. Re:Rugby players don't wear high tech helmets by Anonymous Coward · · Score: 0

      "And the answer is "Yes, of course they all do. Have you met any rugby players?""

      American football is Rugby for sissies who need armor to protect them from the nasty adversaries.

    5. Re:Rugby players don't wear high tech helmets by Anonymous Coward · · Score: 0

      "And the answer is "Yes, of course they all do. Have you met any rugby players?""

      American football is Rugby for sissies who need armor to protect them from the nasty adversaries.

      The nasty adversary today is called CTE. If you don't think that adversary is one to avoid, then by all means take up Rugby, where you can beat common sense out of each other and get paid a lot less money.

    6. Re:Rugby players don't wear high tech helmets by Ormy · · Score: 5, Interesting

      As someone who played rugby extensively, I can tell you this is simply false. American football is more of a [i]collision[/i] sport, whilst rugby is a contact sport. In American football a tackle means running into your opponent as fast as possible to take him out (put him to the ground), after that there is very little 'wrestling' for control of the ball, rugby is the exact opposite in that most of the contact involves wrestling for the ball rather than straight impact. High speed collisions between players are less frequent in rugby so less concussions. Also, as others have said there is no hard protective gear worn in rugby, less hard objects to hit means less concussions. Finally, the style of tackling used in rugby means that two heads banging together in a tackle is less common than in American football, so less concussions. I'm not saying rugby has less injuries overall, just a lower proportion of conussions/brain damage.

    7. Re:Rugby players don't wear high tech helmets by Anonymous Coward · · Score: 2, Funny

      He said brain damage, not writing like a teenager.

      You can distinguish between the two? Man, you're good...

    8. Re:Rugby players don't wear high tech helmets by Anonymous Coward · · Score: 0

      Orange goo, brain damage and America... what an exquisitely explosive mixture!

    9. Re:Rugby players don't wear high tech helmets by Anonymous Coward · · Score: 1

      Surely a helmet (high tech or otherwise) will make almost no difference to concussive injuries, they reduce the chance of a skull fracture almost completely but the rapid change in speed the head suffers is barely changed.

    10. Re:Rugby players don't wear high tech helmets by Hal_Porter · · Score: 3, Funny

      One of the early signs of brain damage is mistyping < as [ and > as ]

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
    11. Re:Rugby players don't wear high tech helmets by hackertourist · · Score: 1

      Let me guess, you played RPN rugby?

    12. Re:Rugby players don't wear high tech helmets by chihowa · · Score: 1

      One of the early signs of brain damage is mistyping < as [ and > as ]

      ...and completely losing awareness of the word "fewer".

      --
      If you want a vision of the future, imagine a youtube comments section scrolling - forever.
    13. Re:Rugby players don't wear high tech helmets by stoatwblr · · Score: 1

      If a rugby player tackled an opponent the way american footballers do, he'd be banned for life.

      As with boxing gloves, the padding players wear doesn't protect _from_ impacts, it allows them to inflict much harder impacts.

      Head trauma is taken extremely seriously in rugby. head high tackles and "blocks" seen in American football are completely banned.

      I know (and tell) the standard jokes about rugby players but having grown up in a rugby-crazy country (I don't like the sport myself) I can tell you that the brain-damaged behaviour usually starts long before they start playing the game - and conversely, that the top players (even the forwards) are skillful and intelligent. (Basically, the ability to be thuggish on the field attracts thugs, but thugs seldom if ever move out of the bottom rung sports teams. Paradoxically a lot of top cricketers are thugs when off the field.)

    14. Re:Rugby players don't wear high tech helmets by Hal_Porter · · Score: 1

      I can tell you that the brain-damaged behaviour usually starts long before they start playing the game - and conversely, that the top players (even the forwards) are skillful and intelligent. (Basically, the ability to be thuggish on the field attracts thugs, but thugs seldom if ever move out of the bottom rung sports teams. Paradoxically a lot of top cricketers are thugs when off the field.)

      It reminds me of the old joke "Rugby is a game for animals played by gentlemen. Football is a game for gentlemen played by animals"

      See also Roy of the Roasters

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
  4. Water and corn starch by mejustme · · Score: 2

    Isn't this what you get when you mix water with corn starch?

    Some of the science behind it explained here: https://www.youtube.com/watch?...

    1. Re:Water and corn starch by pikine · · Score: 1

      Exactly, a non-newtonian fluid with some orange dye.

      --
      I once had a signature.
    2. Re: Water and corn starch by Anonymous Coward · · Score: 0

      This comment is akin to âoehey I know a solid - wood is solid! Therefore all solid things are wood!â

    3. Re: Water and corn starch by I'm+New+Around+Here · · Score: 1

      Only if they weigh the same as a duck, you idiot.

      --
      If you think I voted for Trump because of this post, you're wrong. I voted for Dr. Jill Stein of the Green Party. Again.
    4. Re:Water and corn starch by Anonymous Coward · · Score: 0

      Yes, D3O invented starch (because, clearly they didn't invent water).

  5. On Discovery Channel by sanf780 · · Score: 1

    I watch some sort of light documentary describing this material. This material is used in things like protection bits in motorcycle jackets, and it was ready for me to buy. Other than that, this post sounds like an advertisement.

    1. Re:On Discovery Channel by arth1 · · Score: 1

      I'm not sure how this would be more protective than a hard substance, if it hardens on impact. Is the point that it's more comfortable, at the cost of higher cost and weight?

    2. Re: On Discovery Channel by Anonymous Coward · · Score: 0

      The fluid state would allow for more range of motion than a solid. So allowing it to change viscosity as a function of (shear) force applied provides the advantages of both mobility and protection.

    3. Re:On Discovery Channel by willy_me · · Score: 2

      Because it is soft, it will conform to the required shape. Upon impact, it would harden and more evenly distribute the energy to whatever shape is required. It is therefor more suitable to protect shapes that are dynamic or otherwise unknown during manufacturing. At least, that is the theory. If the shape is known, you are correct is assuming that the benefits are minimal and a more traditional material will offer better performance.

    4. Re:On Discovery Channel by rtb61 · · Score: 2

      So it actually just lessens damage to the skull, distributing the impact over a wider area of the skull but as it acts like a solid, it transfers the full force of the impact to the brain, in fact more than without the helmet, because deformation of the skull would actually absorb some of the force. The gel has zero shock 'absorbing' ability when it acts as a solid as claimed, it transfer all the force to the surface being protected it just distributes it over a wider area. Thick foam under a deformable helmet is probably better for the brain, as the inertial load is reduced and energy is dissipated in the deformation of the helmet and it's heavy duty foam liner. Likely this material should be banned from contact sports as too much inertial impact load is transfer to the brain, you saved a bump on the head but did more damage to the brain instead, not a good way to go. The thicker the layer of foam, the more it deforms, the less the impact of your brain against your skull.

      --
      Chaos - everything, everywhere, everywhen
    5. Re:On Discovery Channel by Anonymous Coward · · Score: 0

      Well, that's just, like, your opinion, man.

      In all seriousness, I'm sure there are people working on this in conjunction with other technologies to make helmets "safer". There's not one magic silver bullet by itself I'm sure.

  6. It is called a Non-Newtonian fluid by skullandbones99 · · Score: 5, Insightful

    See https://en.wikipedia.org/wiki/... for details.

    I see that it was a CNN report, that explains were the big science words were missing...

    1. Re:It is called a Non-Newtonian fluid by thegarbz · · Score: 1, Insightful

      I see that it was a CNN report, that explains were the big science words were missing...

      Slashdot: News for the least nerdy of nerds, partisan political arguments that don't matter.

    2. Re:It is called a Non-Newtonian fluid by Anonymous Coward · · Score: 0

      Or, just watch the all new-and-now-sucking Mythbusters, they seem to have some contract clause that they have to talk about Oobleck at least three times per episode...

  7. A commercial application of a Non-Newtonian fluid by Anonymous Coward · · Score: 0
  8. Orange Goo, nobody say Trump, it's treason by Anonymous Coward · · Score: 0

    And you can't out-treason orange goo - shh, don't tell Mueller!

  9. The BIG question on everybody's mind by mnemotronic · · Score: 1

    Can Gwyneth Paltrow promote Orange Goop for use in a enema?

    --
    The Russians have won. They have made the world a cesspool of distrust, greed, fear and hate.
    1. Re:The BIG question on everybody's mind by Anonymous Coward · · Score: 0

      I'll only buy it if she does a YouTube demonstration.

    2. Re:The BIG question on everybody's mind by CanadianMacFan · · Score: 1

      Actually, I was wondering if anyone had tried to hit Trump's hair when I first saw "Orange Goo."

    3. Re:The BIG question on everybody's mind by sl3xd · · Score: 1

      Screw what Gwyneth Paltro does with Orange Goop.

      I want to see what Covetton House does with it.

      --
      -- Sometimes you have to turn the lights off in order to see.
  10. It's more than "just" a non-Newtonian fluid... by ClarkMills · · Score: 2

    ...as they can cast it into "solid" forms. Try plastering your head with wet cornflour... Apart from the obvious mess & amusement, it will drip off the areas where you want the fluid to stay. The video on the site isn't half bad, watch it...

    1. Re: It's more than "just" a non-Newtonian fluid... by Anonymous Coward · · Score: 0

      ClarkMills 19 minutes ago

      ...as they can cast it into "solid" forms. Try plastering your head with wet cornflour... Apart from the obvious mess & amusement, it will drip off the areas where you want the fluid to stay. The video on the site isn't half bad, watch it...

      A solid fluid? Mind blown.

      I watched the video and was totally unimpressed. Complete marketing BS.

      If you were fooled by that, well, I pity the fool.

    2. Re:It's more than "just" a non-Newtonian fluid... by Anonymous Coward · · Score: 0

      mod parent up please!

      I already wear padding based on the same premisis.
      https://g-form.com/technology

      look past the marketing speak and it sounds to be the same thing. From personal experience I can tell you that it is on par with hard shell pads on its own. Currently i use them for snowboarding, downhill long boarding and mountain biking.

  11. I guess it's normally soft like a liquid by Anonymous Coward · · Score: 0

    But when it receives an impact, it instantly becomes hard like a solid.

  12. Oobleck by Heebie · · Score: 2

    Someone discovered oobleck? (or some similar non-newtownian fluid) So.. corn starch, water, orange food colouring, and a strong, flexible, plastic bag to hold it in? (probably moulded plastic pieces that hold it in a particular shape until it's needed.) Why is this news NOW? Most high-schoolers would have known this recipe back in the 1980's.

    1. Re:Oobleck by DontBeAMoran · · Score: 1

      Because back then, orange food colouring did not exist!

      Wait, that's not it...

      --
      #DeleteFacebook
    2. Re:Oobleck by nasch · · Score: 1

      Or maybe - and this is a bizarre idea - it's NOT corn starch and water.

  13. So basically cornstarch/cornflour by Anonymous Coward · · Score: 0

    So basically cornstarch/cornflour. Anything I missed?

  14. 3DO? by DontBeAMoran · · Score: 1

    British company D3O

    Oh, sorry.

    --
    #DeleteFacebook
  15. Company finds new way to market custard by Anonymous Coward · · Score: 0

    The best part is that it doesn't have to be orange!

  16. Mythbusters by Anonymous Coward · · Score: 0

    Didnâ(TM)t mythbusters recently disprove the use of non newtonian fluids for protection? From memory, the oobleck actually worsened the explosive damage behind it. How is this different?

    1. Re:Mythbusters by dohzer · · Score: 1

      I used some similar padded shorts to protect me while snowboarding, but they didn't do what I wanted.
      The material hardens, but provides zero cushioning. It's probably going to stop something going through your skin, but I could have used a pillow to protect better against pain.

    2. Re: Mythbusters by Anonymous Coward · · Score: 0

      Obviously, a football player has the same damage mechanism as an explosion.

    3. Re: Mythbusters by Brockmire · · Score: 1

      Snowboarding with a pillow? Please try that next time. Bring all your friends, I'm sure they'd like to see that, too.

    4. Re: Mythbusters by Anonymous Coward · · Score: 0

      The episode focussed on the concussive force from the bomb, not shrapnel. They measured oobleck against water and air, and the oobleck resulted in the most damage to objects behind it. They even offered a reasonable explanation as to why it happened.

      So while they're not identical, you shouldn't dismiss it outright. At least until you can explain the physics behind the significant difference. Can you, or were you just being a twat?

    5. Re: Mythbusters by dohzer · · Score: 1

      I forgot that how I look is why I snowboard. Thanks for reminding me of how shallow I didn't know I was, and that I should keep friends who think this way.
      Also, search for a "tail saver".

  17. Silly Putty/Honeywell/NCAA water helmets by Anonymous Coward · · Score: 0

    See subject: My brother (a high ranking field grade U.S. Military officer currently) was a plant mgr. for Honeywell many years manufacturing a compound for battlefield armor vests that DOES stop bullets iirc. I wonder WHAT company made it 1st? Not that it really matters if it does the job & there ARE 'analog compounds' that avoid patent infringement in this arena - one in my subject?

    LOL - SILLY PUTTY does this - the REAL old-school silly putty from the early 70's I had as a kid would bounce or be soft depending on IMPACT acting on i? EXPLODED!

    E.G. - Hit it with a hammer it shattered - lol, give it an electric shock IT WAS C4 EXPLOSIVE like, unstable & shrapnel level explosion fragmentation (why it came off the market iirc).

    Anyhow - on 'jock equipment'?

    When I was an NCAA athlete in the early 80's playing lacrosse (for a national powerhouse), I used the insert in an OLD-SCHOOL football helmet I had (Gladiator 'water helmet') & would REMOUNT the water apparatus via velcro after removing it from my football helmet!

    (It was triangular sponges inside with chambers passing water around channel hoses connecting them vs. water being unable to compress (goes solid under sufficient impact & would fracture your skull). Water helmets imo are more reliable than air helmets that popped imo but heavier - you either had to have a 'donut' neckbrace or a neck like a treetrunk to use one, but it took IMPACTS like no other helmet type imo - not even RIDDELL did better)

    I say this as I was BETTER @ football than lacrosse & I used to 'spear' people w/ my helmet, lol - it 'cooled their jets' on tackles a LOT & this helmet pad type helped (but father warned I had better scholarship shot via the latter, too much steroid users & BETTER athletes than I out there would outcompete me & no chance for pros)

    APK

    P.S.=> Good old fashioned water IS the best protectant, cheap to use & make such constructs too vs. polymer manufacturing processes imo...apk

  18. Cornstarch by Anonymous Coward · · Score: 1
  19. Wrong by lucaiaco · · Score: 2

    Since Rugby players don't hit each others with a helmet, they have almost no concussion or brain damage since it’s the helmet that allows for harder hits and a harder projectile.

    1. Re:Wrong by Anonymous Coward · · Score: 0

      Since Rugby players don't hit each others with a helmet, they have almost no concussion or brain damage since it’s the helmet that allows for harder hits and a harder projectile.

      Rugby players don't intentionally break ribs and fingers either, but shit happens, which is exactly why concussions and brain damage still does occur.

      You can ride a motorcycle without a helmet too. Doesn't make you smart; it just enables you to win your Darwin Award much faster.

    2. Re: Wrong by Brockmire · · Score: 1

      No, you just get cleats to the face. Nastiest black eye I've ever seen was on my cousin who nearly lost an eye.

    3. Re: Wrong by Brockmire · · Score: 1

      Also, it's the rattling of your brain in the skull that is damaging, so harder hits is worse if there's nothing to help absorb the forces.

    4. Re: Wrong by stoatwblr · · Score: 1

      "No, you just get cleats to the face."

      At which point, if whoever did it can be identified, he'll be sent off and possibly banned from the game. "Overenthusiastic rucking" has been banned for a long time due to the injuries inflicted.

      yes you get thuggish behaviour on the field, but thugs don't usually last long in teams who care about their position in rankings.

    5. Re: Wrong by Green+Mountain+Bot · · Score: 1

      And helmet to helmet hits are generally illegal in the NFL. Shit happens.

    6. Re: Wrong by stoatwblr · · Score: 1

      They may be illegal, but concussion is one of the most common American football injuries.

      It simply doesn't happen in Rugby.

  20. Silly Putty by Anonymous Coward · · Score: 0

    I know I'm showing my age .. but isn't that Silly Putty? It behaves the same way ..

  21. I use d3o by genka · · Score: 1

    I've had d3o armor in my motorcycle clothing for years. It doesn't feel that revolutionary different from the ordinary armor. It is slightly more flexible in the warmer weather, but stiffens when cold. I couldn't detect change in the softness when hitting the armor with my fist.

    1. Re:I use d3o by Anonymous Coward · · Score: 0

      I have D3O amour too. Give it a good punch and you will bruise your knuckles! Must be pretty cold where you are as mine never feels hard (NZ).

  22. I need the opposite - self-supporting until hit by raymorris · · Score: 1

    I'd like to find the opposite - something solid enough to be self-supporting at least, until it softens greatly on impact. It's easy enough to find thick liquids that thin under stress (ketchup being one example), but I want it *solid* until it's stressed.

    So far the closest I have is floral foam, which crushes easily into a powder.

    1. Re:I need the opposite - self-supporting until hit by RockDoctor · · Score: 1

      The property you're looking for is thixotropy, converse of this material's "dilatent" property. There are lots of examples, and millions of people dead over the millennia due to the property. A significant number of clay minerals have this property. Pile them together with lumps of lava on a volcano then pile more rocks on top (increasing the stress on the clay between the rocks) during an eruption, and eventually the clay will begin to move. When it will become less viscous, resisting the stress less, so moving faster. That's a feedback loop. The resulting rock avalanche is bad news for people downhill.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  23. Slow Fucking News Day by Anonymous Coward · · Score: 0

    Covering D30 years after it hit the market?

    Hey, I have a thought... how can we make this about social justice and the like? Wouldn't that make it just dreamy?

    D30 is really against white males and it's more of a feminist product. The company won't directly market to any one of caucasian status and instead uses their product to protect those who are fighting the good fight!

    Go slashdot!

  24. a football helmet is just a type of armor. by retchdog · · Score: 1

    lol

    --
    "They were pure niggers." – Noam Chomsky
  25. Not quite corn starch by Tomahawk · · Score: 1

    While similar to how corn flour in water works, it's a different compound. More info here: https://en.m.wikipedia.org/wik...

  26. Also known as Custard by Anonymous Coward · · Score: 0

    A helmet that ensures all the impact is transferred directly through the liquid into the skull seems like a great idea.

  27. soft, gets hard when you hit it? by cellocgw · · Score: 1

    Sounds like the exact definition of someone who needs a dominatrix.

    --
    https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
  28. Urethane by Anonymous Coward · · Score: 0

    I'd guess it's urethane not unlike Sorbothane and Poron XRD.

  29. shear thickening fluid by surd1618 · · Score: 1

    Everyone here is calling it a non-Newtonian fluid, which is correct, but more specifically, it's a shear-thickening fluid. Oobleck is the shear-thickening fluid made of starch and water. Other kinds exist. Here's a Hackaday article about a shear-thickening fluid made of PEG and Repti-cal. I don't know what this orange goo one is made of, but it's probably a mixture of PEG, some dissolved viscoelastic substance, and a specific size of silica particles.

  30. I've used D3O armor for years: OBSERVATIONS by SummitCO · · Score: 1

    I've used D3O in some ski baselayers (Session) as well as bike armor/gloves (POC).

    D3O is flexible, sure. It does not offer great penetration protection.
    It is more protective per volume than foam armor in terms of spreading a focused blunt impact out over an area. (D3O loves the ball peen hammer demonstration)
    However, D3O is not necessarily better than foam for energy absorption (absolutely inferior to foam by weight).
    Foam backed plastic plate is better at both spreading the force out and much better at absorbing impact forces, preventing penetration, and doing it while being lighter and cheaper.

    What this means is that D3O excels where flexible protection is more important than penetration resistance and low profile is more important than weight savings. That makes D3O excellent for joint articulations: knuckles, palms, knees, elbows.

    I don't understand the purpose of D3O in a helmet. To reduce concussions, you want to reduce axonal shear inside the skull. A shear thickening fluid would seem to be counterproductive for this purpose!

  31. Custard by Anonymous Coward · · Score: 0

    I read when younger that custard has this property - get a big bowl of it, whack it really hard with your flat hand, and it's like slapping something solid.