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This is “Tensegrity”

“Tensegrity” combines the concepts of “tension” and “integrity”. Tensegrity structures are characterised by the way that they distribute forces across their surfaces.

A tensegrity structure consists of two different types of parts that interact with one another.

Separate components
The first is a family of separate components that can be assembled under compression. In space and marine applications, these will be short tubes or rods.

Connected network
The other is a set of components that are linked together in a network, and that can be stretched out as a whole. The connections distribute the tensile forces across the whole of the structure. In marine applications, these components would typically consist of cables.

Avoids buckling and collapse
Since the first of these two groups of components are not connected, they do not transfer forces over long distances. This avoids damage caused by buckling, with the risk of collapse, to which the structure would otherwise have been exposed under compression, and permits slender tubes or rods to be used without the structure collapsing.

Adjustable cables
A smart sea-cage constructed according to tensegrity principles would be capable of changing its shape by means of mechanisms that would tighten or slacken its cables.

Example 1: Balloons
Man-made tensegrity structures can be exemplified by the balloon, whose “skin” is made up of a lattice of interconnected atoms, while the air inside the balloon consists of molecules of air that act independently.

If you press your finger into a balloon it does not burst. The atomic lattice distributes the forces over the whole surface of the balloon. Once you remove your finger the balloon returns to its original shape.

Example 2: Plants
Plants are also “constructed” according to tensegrity principles. A young, healthy plant consists of water-filled cells that behave very similarly to the balloon in the first example. The cell membrane is a flexible interconnected network that is kept in tension by the water molecules in the cells. Wind forces, for example, are distributed across the whole plant so that it does not collapse, and can then spring back to its original shape.

It is easy to understand how plants utilise water molecules as building blocks, when we look at a wilted plant. Without the presence of its water molecules, the plant collapses.

by Svein Tønseth

Source: Robert W. Burkhardt: A Practical Guide to Tensegrity Design.