TENSEGRITY STRUCTURING (FULLY ARTICULATED)                                                               


In a fully articulated tensegrity, 
the tensional and compressive forces 
are separated out so completely 
that they appear 
in different specialized parts of the structure 
(ie: struts here - wires there).

In effect,
this system 
consists 
of 2 concentric spherical icosahedrons 
joined diagonally 
by struts and tension members.

The resultant basic pattern 
(in the tensegrity truss system)
of the outer spherical icosahedron 
is the same as described before 
and 
the same is true 
with respect to the resultant basic pattern 
of the inner spherical icosahedron 
on its surface (the inner surface ).

This truss framework 
may be considered 
as made of a series of tripods 
consisting of three struts joined at the center.

Outward pointing tripods 
are arranged in complimentary fashion 
with inwardly pointing tripods.

The vertices of the tripods 
lie in 1 of 2 concentric spheres. 
The base of each tripod 
lies in the sphere 
opposite that containing its vertex.

Tension members 
extend diagonally 
between the respective feet 
of inwardly and outwardly pointing tripods.

The feet of all tripods 
are joined together 
by tension members of wire or cable.

The tensegrity truss (space truss network) 
is tightened into a final rigid structure 
by means of tension members 
extending radially 
with respect to the spherical surfaces 
between the fastenings at the apexes 
of the inwardly and outwardly pointing tripods.

Turnbuckles may be used in these tension members 
to secure the desired final tension 
to hold the structure with the proper degree of rigidity.

At the vertices of the icosacaps, 
there is 
an inwardly or outwardly pointing pentagonal strut arrangement 
in place of 2 complimentary tripods.

It is prefered 
to bridge over the outside or base 
of the pentagonal strut arrangement at each vertex.

The bridging 
consists of 5 struts 
joined together by fastening 
at the vertices of the spherical icosahedron 
and 
joined by fastenings 
to the feet of the inward or outward pointing
tripods immediately adjoining the respective pentagons. 
(Make Sketch)

The Dome may be locked to the foundation 
by great circle bands or cables 
preferably extending along the great circle lines 
which define the edges of the icosahedron.

To my knowledge,
 the absolute master of tensegrity structuring is Kenneth Snelson

Refer to him for further information on the subject
and some extraordinary examples of what is possible 
with tensegrity structuring.


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