giha woo: constrained ball
giha woo: constrained ball giha woo: constrained ball
aug 09, 2010

giha woo: constrained ball

‘constrained ball’

‘constrained ball’ is a drawing aid created by korean product designer giha woo. once attached to the pen, this device helps to draw straight lines without using a ruler. normally, a ball point pen rolls freely in accordance with the ball located at the tip of the pen. however, this writing tool prevents winding lines by helping to move the ball in one direction only. using the installed measuring wheel indicated on the product, users can draw the exact desired line length in both a horizontal and vertical direction, as well as strokes in 45 degree angles.

the mounting area is made with a flexible rubber material helping it adhere to the attached pen.

measurement of line is indicated on the product

  • genial

    y. deyzac says:
  • great!

    juanse says:
  • i don’t see how it will help to draw straight lines. wouldn’t the pen tip and the wheel pivot randomly around each other? but the measurement tool is cool.

    quzy says:
  • interesting, but it’ll work spontaneously inaccurate..

    jj says:
  • your writeup is incorrect. all this device does is remove one degree of freedom. consequently it’ll make it easier to draw straight lines but you can still draw curves or lines at any angle, not just 45° as you perplexity stated.

    spavis says:
  • wow~ good job!!!

    wooki says:

    ericcc says:
  • sounds fantastic, although when do you need it?
    if it absolutely needs to be straight use a ruler, or it doesn’t so just draw freely?
    practice practice practice
    a video of this in action would add more credibility

    Scott says:
  • ridiculous
    you cannot draw a straight line with this device

    eighth says:
  • very interesting! I am heartly wanted this!

    mark says:
  • maybe if it has two wheels it can

    haleluya says:
  • I still love to use my old ruler….

    retired architect says:
  • (- )and another more a senseless tool. using the ruler, or trust your hand as the most perfect tool. its more ecological (…without batterys for any display…or is it with solar?? and without plastics).
    (+)the design is nice.

    leon says:
  • useless tool.
    consider a situation where u use the rubber as the centre of a circle and you use the pen to draw a circle around that centre. your measurement is all wrong as the rubber never moves.

    Naveen says:
  • yes i do agree with this products inability to draw a straigh line as mentioned above. but it would be possible with a steady hand.
    also it could it not be powered by some super small super savy dynamo inside…

    Bp says:
  • I think that this tool is very useful….
    very good idea!!

    tony says:
  • As ridiculous as an automatic shovel.

    Vlad says:
  • exellent idea!

    4624 says:
  • @vlad
    automatic shovel; fabulous idea.. maybe with a rubber shaft to reduce fatigue.

    nicey says:
  • Having two wheels in a line will help in drawing straight lines.

    @bips says:
  • its not multifunctional , few more features in the prodouct would make it popular

    rachana says:
  • I think this is a nice idea but just in paper because it will not do what you really want.
    Nothing is avoiding the devise to go around the pencil; you are relying in a rubber to keep it in place. This is my simple opinion.

    $.$. says:
  • It’s brilliant~~

    ivyjiy says:
  • why not? it’s possible enough~

    mk says:
  • foutus

    joszsze says:
  • Does it works? or its just a concept

    DanRM says:
  • It’s not useful idea…
    What if I want draw line from point A to point B, which are far from each other … laser line is not here

    SnoopyRUS says:
  • This is completely retarded and fails to the ruler for many practical usages.

    A ruler don’t break, is cheap, not constricting the pen, there’s just so so so much that I cba typing. Seriously think about using this for a project not just drawing a line.

    Ruler FTW.

    Pawn says:
  • price point?

    tabby says:
  • Because many posts are irrelevant, i recommend read Edward De Bono’s book about lateral thinking and come again. You can learn to appreciate these projects for what they represent.

    Alecu says:
  • very great idea !!!!!!

    Esraa al sharaa says:
  • love it!
    want one!

    cvvc says:
  • go straight?
    if really… perfect!

    wayne says:
  • So i have to change my grip to use it?
    Idea has potential.

    Nadia says:
  • oh my god i need one of this!

    mariana.wolf says:
  • Is this item commercially available for purchase?

    Beth says:
  • Hi. could you please let me know how can i get the constrained ball

    Thank you

    Ashraf Hendawi says:
  • This is actually a really good idea – I know that sometimes when I’m inking a straight line with a ruler, the ruler will smudge the lines and I’ll have to redo the page all over again. so in these kinds of circumstances having an aid to draw a straight line that won’t impact the line itself would be fantastic!

    Celeste says:
  • I think this is a great tool as I do art work and sign writing and sometimes rulers slip or get in the way. I know I would use it quite often

    Edna says:
  • How do I buy this??

    amy says:

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