CMU School of Drama


Friday, September 11, 2015

Forget Dark Energy: MIT Physicists Have Finally Cracked Overhand Knots

Motherboard: Climbing ropes are amazingly tough (and stretchy), but that doesn't matter a bit if the climber isn't attached to one of those ropes by a bombproof knot capable of taking several thousand newtons worth of sudden impact. It's a peculiar combination of high-tech (ropes are pretty advanced these days) and the amazing, ancient low-technology of a knot.

7 comments:

Ruth Pace said...

I pride myself in being able to tie a perfectly serviceable bowline. However, I can't pretend to understand the reason why a bowline is used for what it is used for, or the physics behind any knot. This article was informative, to say the least. As someone who is friends with several rather serious rock-climbers, I believe that being able to accurately summarize the basic physics of the knot described in this article will allow me to get in with the climber crowd. The knot in question is an overhand knot that has been wrapped 10 times, instead of the customary one. By doing this, researchers calculated (with lots of math and access to MIT research facilities) that it is "...possible to up the knot strength 1,000 times from a single-wrap configuration." While I can't say what sort of impact this discovery will have, I can say with much confidence that I'll be able to impress any rock climber I may meet at a party, where previously, only awkwardness would have ensued.

Unknown said...

I think this video was so interesting, after learning so much about knots last year with Sean West during rigging I've never been able to forget the resourcefulness you have at the palm if your hand if you can just remember the right knot. What struck me about this video is how MIT is actually trying to discuss knot work in very detailed scientific and quantifiable mathematic terms, something that I'm surprised has never happened before. As simple and rudimentary a single knot may seem, there's actually so many interesting scientific operations occurring in the process of forming a knot. From the pressure between the two ends of the rope when pulled, the tension and torsion, and the friction involved when pulling the knot closed there is so much more going on than we might ever think. Dissecting this idea of simple knot work to gain a better understanding of how knots operate in general sounds like really fascinating work, especially since it is so narrow and specific in scope.

Lauren Miller said...

I did not realize that we knew so little about knots. I suppose I have simply been taking their existence for granted these last several years. I know how to tie a bowline or figure eight. I know how and when to use them. As a rock climber I've even trusted them with my life (though, honestly, I prefer a figure eight, despite it being difficult to untie, for climbing since it's easier to check). However, I have never even thought about the specific mechanics of knots. I figured it was just "magic" holding it all together (to clarify: I thought knots just worked and I didn't think too deeply into them). I look forward to MIT's future discoveries. It would be thrilling if there was also research looking into the origin of knots. The bowline, for example, is known as a maritime knot (I believe it was used to tie sails towards the bow of the ship). But beyond that, little is known about how the knot was developed and its uses before the time of European ships. It would be cool to know more about knots, man's real best friend.

Alex Fasciolo said...

I am really excited to have learned about this study into the structure of knots. Though I, and all of us, have a pretty decent foundation for knot tying if through nothing else our freshman stagecraft class, I would be fascinated to learn what mechanics are behind knots in more than an intuitive sense. For example, we all (supposedly) know how to tie a bowline, and it has been told to us, and demonstrated to us, how a bowline is an excellent choice of knot to quickly tie a secure fixed loop at the end of of our rope. Now, taking that knowledge, it would be interesting, at least to me to see shy that is so on a level of understanding higher than “it’s been tested, and if tied properly it has been proven to hold up at this efficiency”. A predictive understanding about knots, a very strong one, would allow a person to come up with a knot for a specific purpose that would be safe and extremely useful. It might lead to MIT developing certain knots for certain purposes, kind of a ludicrous but useful thought. Anyway things turn out, I hope to see another video on this study at some point in the future.

Chris Calder said...

It is crazy to think that a knot, a series of loops, can have that much of an impact on people. I am a design production major so we are required to know a curtain number of standard industry knots. Pedro Reis, an MIT professor, has done hours of research on how the different knot configurations will have a different effects on a rope. It doesn’t take a genious to figure out that each knot serves a different purpose. The point Pedro is trying to make is that there is alot of opportunity to understand more on knots that already exist. He explains in the article that the overhand knot, the simplest knot, can be modified to create a knot that, because of the fiction, not be able to close. Something as simple as that could be considered a break through. Pedro is trying to encourage people to invest time in to various knots with the hope that more break troughs will be made, and in turn making life for others much safer.

Daniel S said...

Rope and knots certainly have their place in theater, though we don’t make full use of the wide variety of knots that are available to use. When I taught knots to my students, there were only 4 knots that I insisted my students know (square knot, clove hitch, bowline, and figure eight). I know how to tie a lot of knots and what they are used for, but that’s about it. I’m not an expert in how much weight they can take or how much force it takes to tie or untie them. It seems like this study will be a great asset to the theater industry in terms of determining loads, capacities, and other useful rigging information. This study may also lead to being able to do more with less (or thinner) rope. The science of rope is a complex one with tensile strength, stretch, inner cores, outer cores various types of braids – the list goes on. In any case, rope can play a big part in how we do things. As safety is paramount in what we do, the increased knowledge in how knots work can help us in our endeavor to maintain safety standards.

Fiona Rhodes said...

This is fascinating. Thought we have all been tying knots since kindergarten, I had never stopped to consider why we use certain knots for certain things—other than simply being told “this is the best for this because ___” pertaining to how it tightened, the shape, the convenient looping. Yet I never bothered to consider the physics involved in the actual knot properties. If they advance the experiment and use actual rope, would they then have to take into consideration the bending properties of the core and outside of the rope, the strength of the individual fibers, the tightness and type of the weave? Another thing that was interesting about this article was what it said about the innate response to symmetry in knots- are they truly less effective when they are “ugly”? How is it part of our system that we understand symmetry to be associated with strength and perfection?