Animals and other biological structures are made strong by their tensioned and compressed parts. Muscles and bones act in unison to increase the strengthen the other. This kind of strength exists also at the cellular level, and is a somewhat new understanding of biological structuring.
Tensegrity is the pattern that results when push and pull have a win-win relationship with each other. The pull is continuous and the push is discontinuous. The continuous pull is balanced by the discontinuous push producing an integrity of tension – compression.
Buckminster Fuller explained that these fundamental phenomena were not opposites, but complements that could always be found together. He further explained that push is divergent while pull is convergent. Tensegrity is a pair, like many co-existing pairs, of fundamental physical laws – push and pull – compression and tension – repulsion and attraction.
Tensegrity Principles
Illustration: Imagine pushing a ping-pong ball on a smooth table with the point of a sharp pencil. The ball would always roll away from the direction of the push, first rolling one way then the other. Push is divergent. Now imagine the difference, if you attach a string to the ping pong ball with tape, and pull it toward you. No matter how other forces might influence the ball to roll away from you, the string would always bring it to you more
and more directly. Pull is convergent.
Another example from common experience occurs when we are pulling a trailer with a car. When driving uphill, one is pulling against gravity. The trailer converges into a course behind the car. If the trailer begins to sway, increasing pull by increasing acceleration can dampen the swaying motion.
Driving downhill, however, the trailer may begin to push. This produces a strong side to side force – divergence. The trailer will begin to sway from side to side. Push again, is divergent. When the trailer begins to push, experts advise to accelerate slightly in order to re-establish pull. Pull is convergent, and the trailer will straighten course.
Tensegrity Theory Explained
The human organism
Two tensegrities are easily recognizeable in systems of the human body. The muscular-skeletal system is a tensegrity of muscle and bone, the muscle provides continuous pull, the bones discontinuous push.
This forms the basis for all human physical mobility. The central nervous system can also be understood as using the analogy of tensegrity where motor neurons and sensor neurons, complement the other in a balance.
The balloon
A more common example of a tensegrity is in a child's balloon. When examined as a system, the rubber skin of the balloon can be seen as continuously pulling (against the air inside) while the individual molecules of air are discontinuously pushing against the inside of the balloon keeping it inflated. All external forces striking the external surface are immediately and continuously distributed over the entire system, meaning the balloon is very strong despite its thin material.
The automobile tire works the same way. It is the tensional integrity in in the tire that yield a low failure rate despite the wear of high speeds and long miles.
A tensegrity then is any balanced system composed of two elements – a continuous pull balanced by discontinuous push. When these two forces are in balance a stabilized system results that is maximally strong.
Larger structures
Tensegrity also refers to a means of creating structures.
Tensegrity was first explored by artist Kenneth Snelson to produce sculptures such as his 18 metre high Needle Tower (1968). The idea was adopted into architecture in the 1980s with David Geiger designing the first significant structure - a competition hall for the Summer Olympics of 1988.
The term 'tensegrity' was coined for Snelson by Buckminster Fuller from tensional integrity. His famous geodesic domes are themselves tensegrities:
As Harvard physician and scientist Donald Ingber explains: