## Concentric Five-fold Prisms Datasheet

```        Member Descriptions
[name, end point names, weight (if in objective function),
second power of length (if a constraint), member category,
Obj/Con/Exc (put in objective function, use as a constraint or
exclude from computations), flags]
For assembly purposes, only the name and end point names are
of interest.  The other information may be of interest after
A Practical Guide to Tensegrity Design has been consulted.

# struts
<Member> strut1 p2' p1   0.0      sqr(2.40147) 1 Con CalcClear Inelastic *
<Member> strut2 p4' p5  -1.0      0.0          1 Obj CalcClear Inelastic *

# side tendon
<Member> side1  p4' p1'  0.0      sqr(1.0) 3 Con *
<Member> side2  p4  p4'  0.0      sqr(1.0) 3 Con *
<Member> side3  p1  p4   0.0      sqr(1.0) 3 Con *

# end tendons
<Member> end1   p2  p1   0.0      sqr(1.0) 2 Con *
<Member> end2   p2' p1'  0.0      sqr(1.0) 4 Con *

In-Situ Member Lengths
These are the lengths of the members when they are in place
and prestress is applied.  The strut lengths are from
screw-eye center to screw-eye center, as are the tendon lengths.
These values are in model units.

strut1:      2.40147    strut2:      2.40147     side1:            1
side2:            1     side3:            1      end1:            1
end2:            1

Relative Member Prestress Force Magnitudes
These values are useful for developing an assembly
strategy for the structure.  The tighter tendons are much
easier to tie in place early on, while the looser tendons
can be left to the last.  This information is also used
to adjust tendon lengths since the measured length of a tendon
will be shorter for a highly-stressed tendon with the same
in-situ length as a tendon which is not so stressed.

strut1:     -1.39986    strut2:     -2.40147     side1:      1.90028
side2:      2.50822     side3:      1.90028      end1:      1.40999
end2:      1.40999

Construction Lengths (in millimeters and halves)
The construction length of a tendon is less than the in-situ
length since when the tendon is measured off it isn't under
any prestress force.  The construction length for the strut
represents the length of the 5/16-inch-diameter wooden dowel.
Braided nylon fishing line was used for the tendons.
Prestress forces are assumed to affect tendon lengths and
not strut lengths.

Elongation of Tendon of Unit Cross Section
Under Force of Average Magnitude (fraction)> 0.02
Length Scale Factor> 212/2.40147
Strut and Tendon Hub Adjustments - s;t> 7.0 4.0
(The 7.0 mm adjustment for the strut is the amount
the screw-eye center extends from the dowel.  The 4.0 mm
adjustment for the tendon is half the outer diameter of the
screw eye.)

strut1: 198 0    strut2: 198 0     side1:  78 1     side2:  78 0
side3:  78 1      end1:  79 0      end2:  79 0
```

Concentric Five-fold Prisms with Point Labels

 ```structure file: tprism/x5girdle2.rc variable file: tprism/x5girdle2.dat digit list: src/mm.dls ```

CONTACT:

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

e-mail: bobwb@juno.com