Tensegrity structure

Kenneth Snelson Needle Tower (1969) – 90 x 18 x 18 feet. The Netherlands

Tensegrity – term coined by architect Buckminster Fuller. “tensional” and “integrity”. These unconventional structures maintain their stability, or integrity, through a pervasive tensional force, hence the term tensegrity. In 1949, Fuller’s student, the sculptor Kenneth Snelson, created the first structure to be defined as a “tensegrity”. Using two X-shaped wooden struts suspended in air by a taut nylon cable, Snelson captured the defining features of tensegrity:

  • biotensegrity – mimics the human skeleton – bones for compression, tendons for tension

What’s the problem?
NASAs Squishable Ball Bot video (5:55) – The “Super Ball Bot”, under development at NASA Ames, is a robotic exoskeleton designed to land on the surface of Titan without a parachute or airbag. It can then roll about the surface by adjusting its shape.

  • Ask – Create a simple, light-weight structure that can land on a planet surface and then move around easily.
  • Imagine – What are some structural designs that that can be used? How can these be adapted for use in a planetary lander?
  • Plan, Create – Many ideas were designed with computer simulations and drawing software. Actual robots were constructed to test the best designs.
  • Improve – What are some of the improvements that can be made to the test robots to make them better?

Engineering ideas

  • stability, integrity, tension

Do It
Challenges for you to work on…

  • find some examples of tensegrity structures. Where are they located? Why were they created?
  • make a tensegrity model – 3 dowels with slots in the ends and 3 rubber bands – there will be 2 connections in each end of each dowel to make a 3 dimensional structure. Then try making one with 6 dowels and 6 rubber bands. Dartmouth Structures – Tensegrity (video 6:57)

Learn more…