Why Knot?

By Deane Barker on July 11, 2005

This has been posted to death in the last couple of days, but the image above is of “Why Knot?” — a machine that can tie a necktie in 562 steps. So, why is this interesting? Because it addresses a problem not easily solved by machines. Tying a necktie is simple for humans, but complex for machines. Why?

I imagine it has something to do with the multiple angles and planes of activity that have to be operated on to tie a necktie. Humans can do this without thinking twice about it because we’re much more dextrous than this machine could ever be.

Additionally, humans are tying the tie on themselves, though I’m not sure if this counts as a pure advantage. But think about it — how well could you tie a tie that wasn’t hanging around your own neck? I’m guessing it wouldn’t be easy.

I watched the video on CNN and it’s just excrutiating watching this thing labor through something we find so simple. That’s why I’m intrigued by it — it’s a problem that’s easy for humans, but diffcult for machines, and that difficulty doesn’t stem from lack of processing power.



  1. That is pretty fascinating to watch. I wonder how many times it has to re-do the tie before it gets the length just right. Or am I the only one who has a problem with that?

    The difficulty for a machine to do a simple task like this explains why we’ll always be dealing with sweat shops being run in third-world countries churning out things like Nike shoes and Adidas athletic wear, paying their “employees” $1 a week; the human mind and body is much easier to train and cheaper to employ than coming up with a machine to do the same thing.

    Isn’t it odd how computers are able to quickly solve mathematical problems that are far beyond what we can do, yet a task like tying a tie, which at its root involves mathematics as well, can be accomplished much more quickly by humans. Is it the translation of the mathematics to analog movement that poses the greatest difficulty for machines?

  2. Well that’s just the thing… I think it’s clear that in the abstract a computer can tie a tie. The physical implementation of the thing is hard.

    As for tying a tie on someone (or something) else I think that’s just a matter of learning what to do with your fingers. Awkward at first (like learning to tie a tie in the first place) but imminently doable.

Comments are closed. If you have something you really want to say, tweet @gadgetopia.