Tensegrity Press Releases and Photos


Tensegrity Solutions Assembles Second Obelisk

SHIRLEY, MA -- Tensegrity Solutions completed assembly of a new tensegrity obelisk on Friday, June 18, 1999. It will eventually serve as a free-standing garden trellis, although not much is likely to grow on it in its current woodchuck-infested location. The obelisk is composed of 18 3.5-foot (1.066 m) struts arranged in six layers using an augmented diamond design. It has triangular ends, the apex triangle having a side length of 16.8 inches (.427 m), the base having a distance of 25.5 inches (.648 m) between each of the three foundation points. It is approximately 13 feet (4 m) tall.

This new design uses a modified diamond approach where four tendons, along with an additional zig-zag tendon, surround each strut. It is hoped this new taller and stronger design will give the morning glories more climbing space and be less prone to tilt than the previous design.

Originally an eight-layer structure was attempted without the additional zig-zag tendons. This proved to be unstable for the media used (nylon twine and hardwood stakes) even without the additional weight of climbing plants.

Two photos of the completed structure along with an addendum to this release are available at: http://www.trip.net/~bobwb/ts/tenseg/obelisk2/photo3.htm.

Two computer-generated views of the obelisk:

side view of the second tensegrity obelisk another side view of the second tensegrity obelisk
Two Views of the Second Tensegrity Obelisk

The obelisk is a variation on structures Kenneth Snelson has designed. He calls his realizations towers. The following are links to photos of two of those structures:

Needle Tower (Hirshhorn Museum, Washington, DC)
Equilateral Quivering Tower

The data used for the assembly of the structure are at http://www.trip.net/~bobwb/ts/tenseg/obelisk2/diamond3.htm.

The original obelisk (see http://www.trip.net/~bobwb/ts/tenseg/obelisk/release.htm for the original press release) has been retrofitted with additional tendons to completely triangulate the tendon network. It was hoped this would mitigate the tilting problem encountered last summer as the morning glories loaded the obelisk.

A photo of the retrofitted structure along with a short analysis of its performance is available at:

A computer-generated diagram of the retrofitted obelisk is shown below. The original tendons appear in green. The retrofitted tendons appear in white.

View of the Retrofitted First Tensegrity Obelisk

View of the Retrofitted First Tensegrity Obelisk


Bob Burkhardt
Tensegrity Solutions
Box 426164
Cambridge, MA 02142-0021

e-mail: bobwb@juno.com

Tensegrity Press Releases and Photos