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Amy C. Edmondson
A Fuller Explanation
Chapter 15, From Geodesics to Tensegrity: The Invisible Made Visible
pages 255 through 257


We recall Fuller's great-circle description in which a vast number of gas molecules are bouncing around inside a sphere, with their great-circle chords ultimately describing an icosahedral pattern as a result of spatial constraints. Tensegrity now completes the image.

      Fuller explains that tensegrity provides a tangible demonstration of what happens inside a balloon. We tend to think of the balloon's skin as a continuous surface; however, a more accurate picture is that of a network of molecules in close proximity, such that the spaces between them are smaller than air molecules, allowing the network to act as an effective cage:

      The balloon is indeed not only full of holes, but it is in fact utterly discontinuous. It is a net and not a bag. In fact, it is a spherical galaxy of critically neighboring energy events. (761.03)

Gas molecules push out against the tensed rubber net and a dynamic equilibrium is maintained; compression and tension are in balance.

      Our eyes cannot see the bustling molecular activity of the balloon, and Fuller sees synergetics as a way to help us tune in to this invisible behavior. A high-frequency tensegrity icosahedron does just that:

      In the geodesic tensegrity sphere, each of the entirely independent, compressional chord struts represents two oppositely directioned and force-paired molecules. The tensegrity compressional chords do not touch one another. They operate independently, trying to escape outwardly from the sphere, but are held in by the spherical-tensional integrity's closed network system of great-circle connectors...(703.16)

He elaborates on the parallel, holding up his icosahedral tensegrity that has traveled with him to hundreds of lectures: "This is a balloon, except that the tension components are only placed right where they're needed." (9) It's a balloon with all the excess tension taken out; strings are located only where the strut (molecule) wants to impinge on the sphere's surface.

      We are thus led back to the necessity of three-way great-circling:

      A gas-filled balloon is not stratified. If it were, it would collapse like a Japanese lantern... . Once we have three or more... push-pull paths [of paired kinetic molecules] they must inherently triangulate by push-pull into stabilization of opposite angles. Triangulation means self-stabilizing; which creates omnidirectional symmetry; which makes an inherent three-way spherical symmetry grid; which is the geodesic structure. (766.02-4)

The analogy is complete. Pneumatics are dynamic high-frequency tensegrity geodesic configurations.

      The principle of tensegrity, perhaps more than any other single aspect of synergetics, has yet to be exploited to its real potential in terms of design advantage. But the elegant simplicity of these remarkable structures hints at the nature of a future design revolution—toward innovative designs with unprecedented performance per pound. Finally, the tensegrity system, besides suggesting structural applications, has also provided a useful model in science.

Case in Point: Donald Ingber

One striking example was contributed to the growing list in 1983 by Donald Ingber, then a doctoral student at Yale University working on the biology of tumor formation and malignant invasion. Ingber had been exposed to tensegrity structures in an undergraduate design course—a playful option on the other end of the academic spectrum, which was to influence his vision as a scientist in profound ways. While pursuing his research in cell biology, Ingber began to observe some fundamental similarities between the subjects of his two seemingly opposite investigations. It appeared that tensegrity theory was applicable to biological systems; that is, Fuller's structures exhibited certain dynamic characteristics that were analogous to cell and tissue behavior. Significant structural parallels between the behavior of cellular and tensegrity systems led Ingber to powerful insights about the regulation of cell shape, differentiation, and growth, and thereby suggested a strategy for further investigation. (10)

      Ingber proceeded to build, test, and study tensegrity structures in an effort to understand the implications of his proposed model, and was excited by the results of the comparison. His revolutionary approach has led to significant breakthroughs in his research into cancer formation, which he now continues at Harvard University Medical School. Without a detailed description of Ingber's research, we can still profit by the theme of his radical theory. He proposes a "whole system" approach in which "the architectural form of a tissue may itself serve to coordinate and regulate the shape, orientation, and growth of its individual cells through transmission of the physical forces of tension and compression characteristic of a given three dimensional configuration." (11)

      There is no more appropriate conclusion than that provided by Ingber's own description in his 1983 letter to Fuller:

      The beauty of life is once again that of geometry with spatial constraints as the only unifying principle. It is of interest to note that, as presented in the accompanymg paper, cancer may then be viewed as the opposite of life resulting from a breakdown of this geometric hierarchy of synergetic arrangements. (11)

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