6 ms·

A Letter from Ken Snelson Regarding Buckminster Fuller and Tensegrity (1990)

61 points by itronitron 4y ago

jgtrosh 4y ago
Good to know the original inventor of tensegrity envisaged it for its real purpose: pretty toys to look at, instead of the grand engineering revolution it was touted as.
- Jarmsy 4y ago
  I like tensegrity structures as sculptures and engineering exercises, but do cringe when I see attempts to make things like tensegrity footbridges applying these forms too literally. There have been some neat robots that walk by changing the cable lengths though.
  - jacquesm 4y ago
    Viewed through a slightly fuzzy lens we are doing the same thing.
  - zcw100 4y ago
    I've had fun building several tensegrity sculptures and I agree that it makes me very wary about bridges built on the idea. They have very unintuitive properties that are difficult to appreciate by just looking at them. They appear to be rigid but are actually springy and without pretensioning they are a floppy mess. It seems to be very non linear too with the structure lacking any rigidity as you tension and then snapping into place at the very end. There are some very interesting similarities between tensegrities and bio mechanical structures. I used to think of bones as the scaffolding that holds up my meat parts but it's more like the meat parts and the bones work together as a tensegrity structure.
    - prionassembly 4y ago
      How can I learn to build tensegrity sculptures? Is it something impossible to do without schooling or master-apprenticeship?
      - zcw100 4y ago
        You can get started with some rubber bands and soda straws. You just need a lot of patience. That will get you started but there are a limited number of things you can do with that and the rubber bands won't last being under constant tension and will eventually break. It takes a surprisingly small amount of materials, just something for the struts like dowels and some string. The most difficult thing is choosing how to attach the strings to the rods. It takes a lot of adjustment to get the pretensioning correct so you need something that you can change until you get it where you want it.
      - monknomo 4y ago
        for a cheap start, chopsticks and twine work just fine.
      - Rediscover 4y ago
        Do a search for "tensegrity rods two-nails fuller mailing list" seems to produce a fair number of hits. Also see: An Introduction to Tensegrity by Anthony Pugh, LOC: TA658.2 P85x, copyright 1976, University of California Press, ISDN: 0-520-02996-8 (cloth/hard) or 0-520-03055-9 (paper), 121pp.
      - Isamu 4y ago
        It’s a fun puzzle. The main thing is to only connect the ends of the rods to cables and not to another rod. This means the rods are under compression only and the cables carry all the tension. That’s the basic idea. Additionally they tend to avoid the rods even touching, so that it gives more of an illusion of floating elements.
        zcw100 4y ago
        For something like a rubber band the challenge is that it will tend to pull itself apart before you get the final band attached. For cables that don't stretch the challenge will be it will be a gigantic tangled mess until you tension it. I have no idea how Snelson managed to construct the larger sculptures without killing himself.
    - twic 4y ago
      There is/was a cell biologist, Don Ingber, pushing the idea that cells use tensegrity for their overall structure: https://journals.biologists.com/jcs/article/116/7/1157/27541/Tensegrity-I-Cell-structure-and-hierarchical https://journals.biologists.com/jcs/article/116/7/1157/27541...
- feb 4y ago
  On the other hand, there are some niches where compression tension, aka tensegrity, may have a practical utility. For example, the current lightest hammock stands are inspired by it. The HandyHammock stands [1][2] use cords to reduce the weight of the poles. Sadly, that model is not manufactured nor sold anymore. The small company Tensa Outdoor makes and sells the Tensa4 [3] which is based on an equilibrium with poles and guy lines. They also have plans for a DIY version [4], called tensahedron stand. The DIY 3-person Hammock Stand from The Ultimate Hang is also inspired by tensegrity [5]. The 3-Pole, 3-Person Tensegrity Stand (DIY) is even more impressive [6]. Although none of them are floating like in the sculptures, the concept and the art inspired some practical constructions. [1] https://www.ddhammocks.com/images/products/_ALL_PRODUCTS/Hammock_stands/Handy%20hammock%20stand/Ultralight_hammock_stand_Instructions-Aug-17_Web.pdf https://www.ddhammocks.com/images/products/_ALL_PRODUCTS/Ham... [2] https://theultimatehang.com/2012/12/11/handy-hammock-stand-review/ https://theultimatehang.com/2012/12/11/handy-hammock-stand-r... [3] https://www.tensaoutdoor.com/product/tensa4-hammock-stand/?v=d3dcf429c679 https://www.tensaoutdoor.com/product/tensa4-hammock-stand/?v... [4] https://www.tensaoutdoor.com/make-your-own-tensahedron-stand/?v=d3dcf429c679 https://www.tensaoutdoor.com/make-your-own-tensahedron-stand... [5] https://theultimatehang.com/2013/04/02/3-person-hammock-stand/ https://theultimatehang.com/2013/04/02/3-person-hammock-stan... [6] https://sectionhiker.com/portable-hammock-stands-for-camping-by-derek-hansen/ https://sectionhiker.com/portable-hammock-stands-for-camping...
  - jamal-kumar 4y ago
    Those hammock stands look pretty cool. I met someone who was experimenting with making his own tables this way. Here's some links [1] [2] [1] https://www.copper.org/consumers/copperhome/DIY/cu_tensegrity_table.php https://www.copper.org/consumers/copperhome/DIY/cu_tensegrit... [2] https://beltsandboxes.com/top-5-diy-impossible-tensegrity-tables-the-best-maker-videos-for-your-next-build/ https://beltsandboxes.com/top-5-diy-impossible-tensegrity-ta...
kwhitefoot 4y ago
http://kennethsnelson.net/ http://kennethsnelson.net/ https://www.artsy.net/artist/kenneth-snelson https://www.artsy.net/artist/kenneth-snelson
jacquesm 4y ago
This was written 7 years after Buckminster Fuller died, which means he could not have responded to it. The letter is rather long and the evidence presented isn't all that strong - at least, not in my view, it's possible that Buckminster Fuller appropriated the concept pioneered by a student, it is just as likely that the student picked up the idea from their college professor. The letter that is quoted is not presented (it would have been a strong piece of evidence) and the quotes therein are so damning that I wonder if they are the real thing. For now, not convinced. edit: the wikipedia page: https://en.wikipedia.org/wiki/Kenneth_Snelson https://en.wikipedia.org/wiki/Kenneth_Snelson "Snelson said his former professor Buckminster Fuller took credit for Snelson's discovery of the concept that Fuller named tensegrity. Fuller gave the idea its name, combining 'tension' and 'structural integrity.' Kārlis Johansons had exhibited tensegrity sculptures several years before Snelson was even born. "
- ncmncm 4y ago
  Fuller's chief skill was always self-promotion. It was good to get some important ideas into circulation, but they are not better for having his name attached. Geodesic domes, after all, turned out to be far less important than he insisted, and his "dymaxion" car was a hazard at best. I am completely satisfied to give Snelson credit for what he has brought to our attention.
  - Jarmsy 4y ago
    Also - the first geodesic domes were designed by Walther Bauersfeld over 2 decades before Fuller. https://commons.wikimedia.org/wiki/File:Dome_Jena_UnderConstruction.jpg https://commons.wikimedia.org/wiki/File:Dome_Jena_UnderConst...
  - JackFr 4y ago
    The more I learn of him, the less able Fuller seems. I kind of suspected before, but this letter and the Dymaxion car article last week seem to confirm that he was not an engineer or inventor, scarcely an architect and was more a promoter than anything. (I suppose promoters can always call themselves visionaries.)
gumby 4y ago
I remember encountering Fuller’s work as a kid in the 70s and wondering what the big deal was. I assumed that I just wasn’t smart enough yet / didn’t know enough yet to appreciate it, but unlike many other things it never planted a seed that eventually changed me. Perhaps it was an emperor’s new clothes situation after all. (Snelson going to school with Albers seems much more interesting!)
mistrial9 4y ago
design is obvious in hindsight
jacknews 4y ago
Assuming it's true, it makes you wonder what other ideas are appropriations. Buckminster-Fullerene / Bucky-balls?
- _yb2s 4y ago
  Buckminsterfullerene was discovered after he died, and named after him because of his interest in this type of geometry. I find your post really irresponsible, and consistent with a general trend of trying to 'cancel' Fuller for taking credit for things which he never actually said or took credit for. Fuller never claimed to have discovered the concept of tensegrity, only specific ideas and example inventions that used the principle.
carapace 4y ago
It's not a good week to be a Bucky Fuller fan, between this and the Dymaxion Car piece that went by a few days ago. I don't want to throw the baby out with the bathwater. Bucky's contribution is a vision of what he called "Design Science Revolution": https://en.wikipedia.org/wiki/Design_science_revolution https://en.wikipedia.org/wiki/Design_science_revolution To wit: Our wealth is not really the material things we make nor the factories that make them, rather it's the immaterial principles and knowledge that gives us leverage over the material world. This wealth is all informational in nature, so it can be freely shared without impoverishing the giver. If we apply this wealth of knowledge to solving our material problems efficiently, then there is more than enough matter/energy/room for everyone to live with a good standard of living and greatly reduced manual labor. In other words, science and technology wisely applied can create a kind of secular Utopia. (We still have to contend with the human condition, of course.)

61 points by itronitron 4y ago

Good to know the original inventor of tensegrity envisaged it for its real purpose: pretty toys to look at, instead of the grand engineering revolution it was touted as.

Jarmsy 4y ago
I like tensegrity structures as sculptures and engineering exercises, but do cringe when I see attempts to make things like tensegrity footbridges applying these forms too literally. There have been some neat robots that walk by changing the cable lengths though.
- jacquesm 4y ago
  Viewed through a slightly fuzzy lens we are doing the same thing.
- zcw100 4y ago
  I've had fun building several tensegrity sculptures and I agree that it makes me very wary about bridges built on the idea. They have very unintuitive properties that are difficult to appreciate by just looking at them. They appear to be rigid but are actually springy and without pretensioning they are a floppy mess. It seems to be very non linear too with the structure lacking any rigidity as you tension and then snapping into place at the very end. There are some very interesting similarities between tensegrities and bio mechanical structures. I used to think of bones as the scaffolding that holds up my meat parts but it's more like the meat parts and the bones work together as a tensegrity structure.
  - prionassembly 4y ago
    How can I learn to build tensegrity sculptures? Is it something impossible to do without schooling or master-apprenticeship?
    - zcw100 4y ago
      You can get started with some rubber bands and soda straws. You just need a lot of patience. That will get you started but there are a limited number of things you can do with that and the rubber bands won't last being under constant tension and will eventually break. It takes a surprisingly small amount of materials, just something for the struts like dowels and some string. The most difficult thing is choosing how to attach the strings to the rods. It takes a lot of adjustment to get the pretensioning correct so you need something that you can change until you get it where you want it.
    - monknomo 4y ago
      for a cheap start, chopsticks and twine work just fine.
    - Rediscover 4y ago
      Do a search for "tensegrity rods two-nails fuller mailing list" seems to produce a fair number of hits. Also see: An Introduction to Tensegrity by Anthony Pugh, LOC: TA658.2 P85x, copyright 1976, University of California Press, ISDN: 0-520-02996-8 (cloth/hard) or 0-520-03055-9 (paper), 121pp.
    - Isamu 4y ago
      It’s a fun puzzle. The main thing is to only connect the ends of the rods to cables and not to another rod. This means the rods are under compression only and the cables carry all the tension. That’s the basic idea. Additionally they tend to avoid the rods even touching, so that it gives more of an illusion of floating elements.
      - zcw100 4y ago
        For something like a rubber band the challenge is that it will tend to pull itself apart before you get the final band attached. For cables that don't stretch the challenge will be it will be a gigantic tangled mess until you tension it. I have no idea how Snelson managed to construct the larger sculptures without killing himself.
  - twic 4y ago
    There is/was a cell biologist, Don Ingber, pushing the idea that cells use tensegrity for their overall structure: https://journals.biologists.com/jcs/article/116/7/1157/27541/Tensegrity-I-Cell-structure-and-hierarchical https://journals.biologists.com/jcs/article/116/7/1157/27541...
feb 4y ago
On the other hand, there are some niches where compression tension, aka tensegrity, may have a practical utility. For example, the current lightest hammock stands are inspired by it. The HandyHammock stands [1][2] use cords to reduce the weight of the poles. Sadly, that model is not manufactured nor sold anymore. The small company Tensa Outdoor makes and sells the Tensa4 [3] which is based on an equilibrium with poles and guy lines. They also have plans for a DIY version [4], called tensahedron stand. The DIY 3-person Hammock Stand from The Ultimate Hang is also inspired by tensegrity [5]. The 3-Pole, 3-Person Tensegrity Stand (DIY) is even more impressive [6]. Although none of them are floating like in the sculptures, the concept and the art inspired some practical constructions. [1] https://www.ddhammocks.com/images/products/_ALL_PRODUCTS/Hammock_stands/Handy%20hammock%20stand/Ultralight_hammock_stand_Instructions-Aug-17_Web.pdf https://www.ddhammocks.com/images/products/_ALL_PRODUCTS/Ham... [2] https://theultimatehang.com/2012/12/11/handy-hammock-stand-review/ https://theultimatehang.com/2012/12/11/handy-hammock-stand-r... [3] https://www.tensaoutdoor.com/product/tensa4-hammock-stand/?v=d3dcf429c679 https://www.tensaoutdoor.com/product/tensa4-hammock-stand/?v... [4] https://www.tensaoutdoor.com/make-your-own-tensahedron-stand/?v=d3dcf429c679 https://www.tensaoutdoor.com/make-your-own-tensahedron-stand... [5] https://theultimatehang.com/2013/04/02/3-person-hammock-stand/ https://theultimatehang.com/2013/04/02/3-person-hammock-stan... [6] https://sectionhiker.com/portable-hammock-stands-for-camping-by-derek-hansen/ https://sectionhiker.com/portable-hammock-stands-for-camping...
- jamal-kumar 4y ago
  Those hammock stands look pretty cool. I met someone who was experimenting with making his own tables this way. Here's some links [1] [2] [1] https://www.copper.org/consumers/copperhome/DIY/cu_tensegrity_table.php https://www.copper.org/consumers/copperhome/DIY/cu_tensegrit... [2] https://beltsandboxes.com/top-5-diy-impossible-tensegrity-tables-the-best-maker-videos-for-your-next-build/ https://beltsandboxes.com/top-5-diy-impossible-tensegrity-ta...

kwhitefoot 4y ago

http://kennethsnelson.net/ http://kennethsnelson.net/ https://www.artsy.net/artist/kenneth-snelson https://www.artsy.net/artist/kenneth-snelson

jacquesm 4y ago

This was written 7 years after Buckminster Fuller died, which means he could not have responded to it. The letter is rather long and the evidence presented isn't all that strong - at least, not in my view, it's possible that Buckminster Fuller appropriated the concept pioneered by a student, it is just as likely that the student picked up the idea from their college professor. The letter that is quoted is not presented (it would have been a strong piece of evidence) and the quotes therein are so damning that I wonder if they are the real thing. For now, not convinced. edit: the wikipedia page: https://en.wikipedia.org/wiki/Kenneth_Snelson https://en.wikipedia.org/wiki/Kenneth_Snelson "Snelson said his former professor Buckminster Fuller took credit for Snelson's discovery of the concept that Fuller named tensegrity. Fuller gave the idea its name, combining 'tension' and 'structural integrity.' Kārlis Johansons had exhibited tensegrity sculptures several years before Snelson was even born. "

ncmncm 4y ago
Fuller's chief skill was always self-promotion. It was good to get some important ideas into circulation, but they are not better for having his name attached. Geodesic domes, after all, turned out to be far less important than he insisted, and his "dymaxion" car was a hazard at best. I am completely satisfied to give Snelson credit for what he has brought to our attention.
- Jarmsy 4y ago
  Also - the first geodesic domes were designed by Walther Bauersfeld over 2 decades before Fuller. https://commons.wikimedia.org/wiki/File:Dome_Jena_UnderConstruction.jpg https://commons.wikimedia.org/wiki/File:Dome_Jena_UnderConst...
- JackFr 4y ago
  The more I learn of him, the less able Fuller seems. I kind of suspected before, but this letter and the Dymaxion car article last week seem to confirm that he was not an engineer or inventor, scarcely an architect and was more a promoter than anything. (I suppose promoters can always call themselves visionaries.)

gumby 4y ago

I remember encountering Fuller’s work as a kid in the 70s and wondering what the big deal was. I assumed that I just wasn’t smart enough yet / didn’t know enough yet to appreciate it, but unlike many other things it never planted a seed that eventually changed me. Perhaps it was an emperor’s new clothes situation after all. (Snelson going to school with Albers seems much more interesting!)

mistrial9 4y ago

design is obvious in hindsight

jacknews 4y ago

Assuming it's true, it makes you wonder what other ideas are appropriations. Buckminster-Fullerene / Bucky-balls?

_yb2s 4y ago
Buckminsterfullerene was discovered after he died, and named after him because of his interest in this type of geometry. I find your post really irresponsible, and consistent with a general trend of trying to 'cancel' Fuller for taking credit for things which he never actually said or took credit for. Fuller never claimed to have discovered the concept of tensegrity, only specific ideas and example inventions that used the principle.

carapace 4y ago

It's not a good week to be a Bucky Fuller fan, between this and the Dymaxion Car piece that went by a few days ago. I don't want to throw the baby out with the bathwater. Bucky's contribution is a vision of what he called "Design Science Revolution": https://en.wikipedia.org/wiki/Design_science_revolution https://en.wikipedia.org/wiki/Design_science_revolution To wit: Our wealth is not really the material things we make nor the factories that make them, rather it's the immaterial principles and knowledge that gives us leverage over the material world. This wealth is all informational in nature, so it can be freely shared without impoverishing the giver. If we apply this wealth of knowledge to solving our material problems efficiently, then there is more than enough matter/energy/room for everyone to live with a good standard of living and greatly reduced manual labor. In other words, science and technology wisely applied can create a kind of secular Utopia. (We still have to contend with the human condition, of course.)