Cindy Sergent's Design Page
home|
art|
bubble|
travel|
thoughts
...........Cindy's Design Page
Visit Innotia Jewelry to see Cindy's handcrafted beadwork.
Click here to contact Cindy.
 |
 |
|
Here is a very interesting design exercise -- tensegrity. A little background about tensegrity. Let me quote from the book
"An Introduction to Tensegrity" by Anthony Pugh, University of California Press, Berkeley and Los Angeles, California.
|
|
The concept of tensegrity, in which tensile and compressive elements are carefully balanced to
achieve structural integrity, permits the fabrication of curious structures, their rigid elements not touching, but suspended
as if by magic, interlaced by a network of tendons.
|
|
R. Buckminster Fuller was the first to notice the structure in nature that used a balance of tension and compression, and
that the compressive components were usually much heavier and bulkier than the tensile components. This is necessary
because a tensile component need only be thick enough to take the imposed load, whereas a compressive component
needs an additional thickness of material to prevent it from buckling.
|
So, here is the problem statment:
- To design and fabricate a toy structure of tensegrity that must occupy 5 cubic feet of volume.
- The structure must support 50 lbs, at least 2.5 feet from the ground.
- The structure must be made of metal tubing and wire.
- No compression member of the structure may be longer than 8".
- Design and construct a package to enclose the fully assembled structure which protects it from damage when
you sit on any side of the package.
- Of course, be designerly. Be very concerned with elegances of solutions including forms, color, graphics
and a well planned approach to the problem.
We had less than a month, May 12 - June 7, to understand, design, fabricate and document.
|
After study, some conceptual sketches, and prototyping, I decided to build the structure with 4 octahedra. Here is the
final prototype constructed with dowels and rubber bands. I don't remember how I put them together, but I know it
wasn't easy.
|
|
You can see the top octahedron and the 2 front ones. One end of each of the bottom 3 octahedra forms a triangle and
they are connected to the top octahedron, forming another triangle.
|
| This is the prototype of the packaging container.
|
|
Now, I have the design, manufacturing poses another set of problems. There are 2 major problems to solve: one is to
connect the 6 8"-tubes together to form a octahedra; another is to connect the 4 octahedra to complete the tensegrity
structure.
