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Read here about issues of scale and how they relate to tensegrity.

Micro-scale Tensegrity

Electron Beam and Spectra fibers

3D printing of micro-scale tensegrity structures was done by using electron beam melting in Ti6Al4V titanium alloy. The structure had temporary supports that were post-tensioned employing Spectraâ fibers [2].

Micro-stereolitography with Swelling Gels

3D printing of micro-scale tensegrity structures has been proposed by using a projection micro-stereolitography (PμSL) system [3], an additive fabrication technique based on a photo polymerization reaction. Liquid polymer resin is photo-chemically converted into a solid 3-D micro-structure in a layer-by-layer fashion. PmSL allows the use of swelling gels that, when dried, contract and create the necessary prestress [1].

Fractal Tensegrity

Tensegrity can be implemented on multiple scales in a single structure in a fractal implementation.

R. Buckminster Fuller proposed such an iterative process in his work on tensegrity. Keeping in mind that "there are no solids in structures, ergo no solids in Universe." Fuller considered the typical tensegrity, composed of struts and tendons, and imagined substituting for any individual strut in the tensegrity, another tensegrity, and so on. In his words:

The tensegrity masts can be substituted for the individual (so-called solid) struts in the tensegrity spheres. In each one of the separate tensegrity masts, acting as struts, in the tensegrity spheres it can be seen that there are little (so-called) solid struts. A miniature tensegrity mast may be substituted for each of those solid struts. The subminiature tensegrity mast within the tensegrity struts of the tensegrity struts of the tensegrity sphere and a subsubminiature tensegrity mast may be substituted for each of those solid struts, and so on to subsubsubminiature tensegrities until we finally get down to the size of the atom and this becomes completely compatible with the atom for the atom is tensegrity and there are no "solids" left in the entire structural system. There are no solids in structures, ergo no solids in Universe. There is nothing incompatible with what we may see as solid at the visual level and what we are finding out to be the structural relationships in nuclear physics.

Part/Whole Relations

Tensegrity, by its very nature, requires consideration of the relationship of a whole to its parts. This whole/part consideration implies one level of scale, or order of magnitude: the whole is an order of magnitude above the parts.

The whole is simply the structure considered as one, single unit. In a classic tensegrity structure, the whole is characterized by structural integrity instantiated by prestress and stiffness. The parts of this whole are conventionally divided into local islands of compression struts joined by global, interconnected networks of tension tendons.

Links and References

For more reading about scale, see the Scalometer blog and associated wiki.

[1] Amendola, A., Nava, E.H., Goodall, R., Todd, I., Skelton, R.E., Fraternali, F., 2015. On the additive manufacturing and testing of tensegrity structures. Compos. Struct., 131, 66-71.

[2] Email Fernando Fraternali, citing the following work: Ada Amendola and Fernando Fraternali, from the Department of Civil Engineering of the University of Salerno (Italy), and  Howon Lee, from the Department of Mechanical Engineering of the Seoul National University (Korea).

[3] Han, D., Lee, H. et. al., 2019. Rapid multi-material 3D printing with projection micro-stereolithography using dynamic fluidic control. Addit. Manuf., 27, 606-615.

Read more about other tensegrity concepts: