- What is tensegrity?
- How do you adjust the tension on your sculptures?
- Do the wires thread through the tubes?
- What happens if a wire is cut?
- Your work is often associated with the ideas of Buckminster Fuller. What was your relationship?
- What’s the difference between what you do and what an engineer does?
- I’d like to build my own tensegrity structures. What’s the best way to learn?
- Are table size reproductions or possibly kits available?
- It seems to me that “Needle Tower” or “E.C. Column” would make a magnificent transmission tower, especially since the standard ones are not exactly things of beauty.
- Is the Star of David one sees when I look up through your “Needle Tower” meant as a religious symbol?
- Are there problems with people climbing you artwork?
Email Kenneth Snelson at email@example.com.
A: Tensegrity, the word, has become so confused through multiple uses that it calls any definition into question. This is the reason I’ve long advocated “Floating compression” — though by now it’s clear I’ve lost that battle. Buckminster Fuller coined the word tensegrity from tension and integrity five years after I first demonstrated to him the principle I had discovered. Creating this strange name was his strategy for appropriating the idea as his own. By now tensegrity is a buzzword that seems to apply to all kinds of structures that use tension members, familiar things that aren’t enhanced by calling them by a novel word. Spider webs, bicycle wheels, kites and physical exercise regimens, do not require a new word such as tensegrity. The ancient form of kite frame, two sticks crossed with string-connected ends, comes closest to this type structure; what’s missing is that the sticks do touch one another at their crossing point. As best I can define tensegrity, based on what my sculptures contain:
Tensegrity describes a closed structural system composed of a set of three or more elongate compression struts within a network of tension tendons, the combined parts mutually supportive in such a way that the struts do not touch one another, but press outwardly against nodal points in the tension network to form a firm, triangulated, prestressed, tension and compression unit.
Why “triangulated”? The reason is that it’s possible to build such a structure whose network is non-triangulated. Such structures are flaccid and decidedly not firm.
A: It’s analogous to tuning a stringed instrument. In assembling the sculpture for the first time, I invariably need to change some of the tension members, remaking them either longer or shorter to achieve the right amount of prestressing. Every part depends on every other part, compression and tension members alike, so that knowing which wire to alter is a matter of experience. After the final adjustment, further changes over time are seldom necessary.
A: Each wire is separate and connects only specific points from one tube end to another, performing a particular task. The wires are never threaded through the structure like a string of beads as appearances might suggest.
A: Cutting a wire in a simple tensegrity structure with few parts causes a major deformation or collapse. The more complex the structure, depending on which wire is removed, the milder the damage.
A: I was an art student just after World War II and I was attracted to the work of the Russian Constructivists and to the larger world of geometrical art that evolved worldwide in the first-half of the twentieth century. In the Summer of 1948, when I was twenty-one, Buckminster Fuller became a huge influence from the moment I met him at Black Mountain College in North Carolina. I went there from my home in Oregon to study only with Josef Albers the Bauhaus Master. Professor Fuller arrived for the summer session as a substitute for an architecture professor who withdrew at the last minute. It was Fuller’s first teaching job.
His public lecture on the evening he arrived from New York was surprising and exhilarating, especially because we knew nothing about him and it was clear to all that his ideas were novel. He was not the celebrity that he later became. So in those short summer weeks virtually the entire small college, sixty or seventy people, decided to sign up and audit Bucky Fuller’s class. I was assigned the role of class monitor.
Although his long lectures covered a menu of subjects, for me his presentation of three-dimensional geometry and its structural associations, delivered under the label “Energetic Geometry”, was fresh, a bit mystical, and fascinating to all of us art-and-architecture students whose introduction to form was largely from the square-and-cube world of the Bauhaus. Even so, in his structure/geometry inventory there was no such thing as tensegrity; and the geodesic dome was then a pattern of thirty-one great circles surrounding a sphere, not the now familiar form based on the icosahedron.
All during the summer, the resident math professor Max Dehn softly protested that we students could have looked up all of “Bucky’s” geometry right there in the math library, but Professor Fuller, superb salesman that he was, convinced us non-mathematical art students that he had discovered these marvelous geometrical relationships for the first time and for the good of humanity. But what he did add to it was his engineer’s focus on the structural stability — or not — of the Platonic and Archimedean polyhedra – as well as an almost religious self invented doctrine which asserted that here resided the deepest secrets of nature, heretofore hidden from mankind. Whatever he claimed, he surely threw fresh light on the subject. It was this study and this sensibility, tying together form and structure, plus that strange mysticism which greatly affected me during my young Black Mountain summer sessions over fifty years ago. What Buckminster Fuller came away with in the following summer session, 1949, was work I had done at home that winter, an original idea, now called tensegrity. Also see: http://www.grunch.net/snelson/rmoto.html
A: I’m not an engineer nor a scientist. My training is in art and I make art. Engineers make structures for specific uses, to support something, to hold something, to do something. My sculptures serve only to stand up by themselves and to reveal a particular form such as a tower or a cantilever or a geometrical order probably never seen before; all of this because of a desire to unveil, in whatever ways I can, the wondrous essence of elementary structure.
A: Building simple structures with basic materials such as chopsticks or soda straws and string or rubber bands is the best way to understand what the push and pull forces are doing. The artist/mathematician George Hart has an amazing number of ideas and endless information at his website, http://www.georgehart.com/virtual-polyhedra/straw-tensegrity.html, about geometry as well as instructions for making simple tensegrity structures.
A: No except for small sculptures which, because of the way things go in the art market, always up, they have gotten to be expensive. They’re handled by Marlborough Gallery, New York.
A: Building a tower for such purpose is not very promising since these structures, pure tensegrity that is, are quite elastic and flexible; too much so for use as antennas with dishes mounted on top. Swaying in the wind might be a disadvantage.
A: No, although the double triangle is there to be sure. The six pointed star often seen in my sculptures is not intended as a symbol of any kind; nor are the many crosses. Six pointedness in this case comes out of the natural geometry of three elements (compression struts) at each layer or module. The sets of three alternate with right with left helical modules, adding up to six when seen looking up through the tower for example. It’s for that reason you see a six pointed star. A five pointed star would be a challenge since dividing five by two gives only two and a half. Two and a half compression members doesn’t compute.
A: Occasionally, but I try to put the outdoor pieces out of harm’s way whenever possible. So far luckily no one has gotten hurt.