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New Shape Born From Rubber Bands

Posted by Unknown on from the sproingees dept.

sciencehabit (1205606) writes "Physicists playing with rubber bands have discovered a new shape. In an attempt to create a spring that replicates the light-bending properties of cuttlefish ink sacs, a team of researchers suspended two rubber strips of different lengths. Connecting the bottoms of the two strips to a cup of water, the shorter band stretched to the same length as the longer one. After gluing the two stretched strips together, the researchers gradually drained the water from the cup. As the bands retracted and twisted from the reduced strain, the researchers were shocked to see the formation of a hemihelix with multiple rainbow-shaped boundaries called perversions. The team hopes their work inspires nanodevices and molecules that twist and transform from flat strips into predetermined 3D shapes on demand." There are several videos attached to the original paper, and all can be viewed without flash.

26 of 120 comments (clear)

  1. Old phone cords? by Anonymous Coward · · Score: 5, Insightful

    Back when I used corded handsets a lot one could strech them out far enough and then when they retracted you would get a very similar shape....

    1. Re:Old phone cords? by nine-times · · Score: 5, Funny

      No, it's a new shape, dammit!

      I have also invented several new shapes. One of them, I draw part of a circle, and then it turns into a squiggly line for a while, and then a quarter of a square, followed by a third of an asymptote. Another time, I drew 3 squiggly lines connected to a 4th line that was almost straight but still a little squiggly. I call it a squiggle-square.

    2. Re:Old phone cords? by alphatel · · Score: 4, Funny

      No, it's a new shape, dammit!

      I have also invented several new shapes. One of them, I draw part of a circle, and then it turns into a squiggly line for a while, and then a quarter of a square, followed by a third of an asymptote. Another time, I drew 3 squiggly lines connected to a 4th line that was almost straight but still a little squiggly. I call it a squiggle-square.

      By the Gods boy, where are your patents?

      --
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    3. Re:Old phone cords? by gatkinso · · Score: 2

      That is exactly what I thought the moment I saw this.

      Kids these days.... sheesh.

      --
      I am very small, utmostly microscopic.
    4. Re:Old phone cords? by jovius · · Score: 2

      Now re-create that technological relic with two joined flat and straight surfaces by simulating a natural growth pattern, and maybe apply what you found to study plant root formation for example. The summary is a bit over the top, but the science is sound in the experiment anyway. This deepens understanding how nature has worked out the mechanics of the helical forms.

    5. Re:Old phone cords? by freeze128 · · Score: 4, Funny

      I followed your instructions, but I only got a sketch of Homer Simpson.

    6. Re:Old phone cords? by guruevi · · Score: 5, Informative

      You're missing the point of the paper. The paper is not there to show "new shapes" that is the reporter that clearly doesn't understand what's going on saying that.

      The paper explains HOW these things happen and HOW specific shapes can be modeled (aka calculated or created on purpose) in function of various forces and aspect ratios. They for example, show how to consistently get such a 'kink' (perversion) like the one in your phone cord on every "turn".

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    7. Re:Old phone cords? by garyebickford · · Score: 2

      Also rubber band airplanes. Wind them up, at one point you get exactly that shape. IDK if the math of the shape was ever explored though. Oftentimes 'discoveries' are things that we, the great unwashed, saw all the time but never noticed. And that's OK - we need people who say, "That's funny..."

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  2. New? by ntshma · · Score: 5, Insightful

    My telephone cord at work has been like this for years.

    1. Re:New? by Stele · · Score: 4, Funny

      But it's on the Internet...

    2. Re:New? by Austrian+Anarchy · · Score: 2

      My telephone cord at work has been like this for years.

      If only any of us had thought of a catchy name for that shape, rather than cursing when we tried to use the phone, we would be on the cover of Slashdot too.

      --
      Time Bomber the Book coming soon.
    3. Re:New? by gstoddart · · Score: 5, Informative

      To be fair, the abstract doesn't say anything about a new shape, nor do I see anything in the introduction.

      Kinda yes, kinda no:

      More generally, we introduce the term hemihelix to describe multiple reversals in chirality connected by perversions.

      So, they've come up with a term to describe this.

      And, lest anybody think they were unaware of the phone cord thing:

      Although perversions can also be introduced manually, for instance, by the simple operation of holding one end of a helical telephone cord fixed and twisting the other in a direction counter to its initial chirality

      So, they know that people have seen this. They seem to be the ones introducing the term they've applied to describe it.

      A new name to an old shape, but mostly they've figured out how to predict it, and then hopefully how to plan for it to build specific shapes.

      --
      Lost at C:>. Found at C.
  3. Score: -1, Redundant by ArcadeMan · · Score: 5, Funny

    My old phone cord.... never mind.

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    1. Re:Score: -1, Redundant by bughunter · · Score: 2

      Mod Parent up, I'm gonna post instead.

      perversions can also be introduced manually, for instance, by the simple operation of holding one end of a helical telephone cord fixed and twisting the other in a direction counter to its initial chirality

      This explains why I must keep my phone on the left side of my desk to avoid tangling the handset cord. When it's on the right, I give the handset nearly a full twist to get it from the cradle to my left ear (to keep my right hand free for writing/mousing) -- and then another twist back to set it back down on the cradle. Since I'm grabbing with my right hand, the right hand twist is "counter to its initial chirality," which is left handed for most cords I've seen. (Left hand rule - wire coiling in the direction of the left fingers advances in the direction of the left thumb.) After only a few months, it's twisted into such a perverted state, it won't stretch without tangling, and I have to replace it.

      Keeping the phone on the left seems to prevent this... the half turn picking up the phone is left-handed, concurrent with the chirality of the coil. Also it's closer to a half twist than a full twist.

      Nice to finally have an answer to why this works the way it does.

      --
      I can see the fnords!
  4. Here's a YouTube Video of it by Nova+Express · · Score: 2

    This will be a little easier to view.

    Not seeing anything groundbreaking off the top of my head...

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  5. Two strips one cup by PNutts · · Score: 4, Funny

    No thanks.

  6. The real discovery here: by Anonymous Coward · · Score: 4, Funny

    People have started to rediscover things that were perfectly ordinary 20 years ago. If it is not mentioned anywhere on the Internet or you cannot find it because there is no word for it, then it becomes a new invention when stumbled upon.

    I have just filed a patent for a sound storage device that consists of two spools. The sound is stored in direct form so that it can be sent to a sound emitting device without DAC. I call it Direct Sound(tm).

  7. Going for an Ignobel Prize? by tomhath · · Score: 2, Insightful

    Maybe I'm missing something here too. Looks like a twisted up rubber band to me. Although I'm pretty sure I invented a new shape the first time I used monofilament fishing line.

  8. WMV fail by eddy · · Score: 2

    Windows Media Video 9 files without any identifying suffix in the downloadable archive. Good going.

    Assholes.

    --
    Belief is the currency of delusion.
  9. And we have a strong contender... by OneAhead · · Score: 4, Funny

    Handily in time to contend for the 2014 Ig Nobel price.

  10. The usual story: flawed summary by jbmartin6 · · Score: 4, Informative
    I don't see anything in the paper claiming to have found "a new shape". It also isn't clear why the word "shocked" is used, other than perhaps the results was unexpected. I guess an excerpt from the paper sums it best:

    A recent, simple experiment using elastomer strips reveals that hemihelices with multiple reversals of chirality can also occur, a richness not anticipated by existing analyses. Here, we show through analysis and experiments that the transition from a helical to a hemihelical shape, as well as the number of perversions, depends on the height to width ratio of the strip's cross-section. Our findings provides the basis for the deterministic manufacture of a variety of complex three-dimensional shapes from flat strips.

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    1. Re:The usual story: flawed summary by RoverDaddy · · Score: 2

      The title is basically buzzfeed for science.

      "Which Perverse Hemihelical Chirality are you? Take this quiz to find out!"

      --
      RETURN without GOSUB in line 1050
  11. This shape by magsol · · Score: 2

    literally ruins slinkys.

    --
    "I'd just like to emphasise that taking a million years isn't a metaphor here..." -Rich Bradshaw
  12. Not a new shape, a new method by wjcofkc · · Score: 2

    So it's safe to say that the summary is botched, however, that does not mean that the article is not still interesting enough to be deserving. What we have is an unexpected outcome to an experiment. They created a known structure using a new method, where the method of creation may make the shape promising to engineering applications.

    --
    Brought to you by Carl's Junior.
  13. Re:Doesn't occur in nature? by omnichad · · Score: 2

    If your calamari turns into rubber bands, you're probably overcooking it.

  14. Balsa Airplanes by aaronb1138 · · Score: 2

    I was getting shapes like that from rubber band powered balsa wood airplanes back in the 80's during both winding and unwinding. Regarding the unwinding, I used to love testing the thrust a few times to see if there was a magical way to wind it to get more airflow and for longer. I'm sure older people have witnessed similar many years prior. Nothing new here.