Steve Baer, Zomeworks Corporation, Albuquerque, New Mexico. Signed S.C.B., August 1970. Preceded by the Dome Cookbook (Lama Foundation, 1968).

Complete digitized text extracted from the EPUB at solar-fool-wiki/zome_primer/zome_primer.epub. Order: Preface, Contents, chapters 1–15, List of Figures, List of Tables, Bibliography. The epub’s trailing Index was excluded — it is an erroneously-appended index from a separate work (Buckminster Fuller / Synergetics terms), not part of the Zome Primer. Figures noted inline as [figure: …]. The file 1970-08-01-zome-primer.md is an editorial summary.

---

Preface

This booklet has first an elementary explanation of the geometry of Zonohedra, then a more difficult account of the growths of the thirty-one zone star. This system, based on the 31 lines that pass through the center of an icosahedron and either a vertex, edge midpoint or face midpoint is new and unusual.

I have applied for a patent on this structural system. The patent is assigned to Zomeworks Corporation. The predecessors of this system are the octet truss and the MERO space grid system. The relative potentials of these systems are discussed briefly by a comparison of their geometric possibilities.

The forms possible using this system are limitless; there is no attempt here to explore these possibilities—the examples shown are small probings. The booklet describes the mathematics of the process that creates these limitless forms.

The framework for the Robert Ford residence was designed by Jim Welty and Robert Ford.

The shallow rectangular based trusses were designed by Berry Hickman of Zomeworks who also introduced the excellent plastic ball joint used throughout in the models photographed.

The design and manufacture of the 6-zone aluminum joint was done by Otto Jung of Design Industries in Albuquerque.

Ken Leonard did the layout and both he and my wife, Holly, gave much editorial assistance.

S.C.B.

Albuquerque

August 1970

Contents

• Preface

• 1 Zomes, Domes and Clusters

• 1.1 What Are Zomes?

• 1.2 What is the Difference Between a Zome and a Geodesic Dome?

• 2 Zonohedra

• 2.1 What are Zonohedra?

• 2.2 Face Planes of Zonohedra

• 2.3 Section Stars and Face Planes

• 2.4 Division of Zonohedra into Parallepiped Cells

• 3 Regular Ways of Arranging Lines in Space

• 3.1 Three Zones

• 3.2 Four Zones

• 3.3 Six Zones

• 3.4 Ten Zones

• 4 Clustering

• 4.1 Twenty-one Zone Structure

• 4.2 Twenty-one Zone Zome Clusters

• 5 Stretching a Zone

• 6 Trusses: Twenty-one Zone System

• 6.1 6 A Lines 15 C Lines

• 6.2 Triacontahedron

• 7 Critical Constants

• 7.1 Six Zone

• 7.2 Ten Zone

• 7.3 Ten Zone

• 7.4 The Appearance of the CTn Series in the Dimensions of the Triacontahedron and the Enneacontahedron

• 8 Symmetries of a Regular Thirty-one Zone Star

• 9 Five-Fold Symmetry

• 9.1 Growth and Generations of Stars

• 10 Sections

• 10.1 R Section

• 10.2 S Section

• 10.3 T Section

• 10.4 V Section

• 10.5 X Section

• 10.6 Y Section

• 10.7 The Formation of Triangles

• 10.8 A Star Problem

• 11 The Divine Proportion

• 11.1 Tau Power Series

• 11.2 Pattern and Rules

• 11.3 The Fibonacci Numbers

• 12 Coherence Proofs

• 12.1 Two Dimensions

• 12.1.1 Definition 1

• 12.1.2 Definition 2

• 12.1.3 Definition 3

• 12.1.4 Definition 4

• 12.1.5 Definition 5

• 12.1.6 Definition 6

• 12.2 Three Dimensions

• 12.2.1 Definition 1

• 12.2.2 Definition 2

• 12.2.3 Definition 3

• 12.2.4 Definition 4

• 12.2.5 Definition 5

• 12.2.6 Definition 6

• 12.2.7 Definition 7

• 12.2.8 Definition 8

• 12.2.9 Definition 9

• 13 Joints

• 14 The Stars of Other Systems

• 14.1 Octet Truss

• 14.2 The Mero Space Grid System

• 15 Hardware

• List of Figures

• List of Tables

References

• Index

1 Zomes, Domes and Clusters

1.1 What Are Zomes?

A Zome is a man-made structure derived from zonohedra. The zones of the zonohedron may be stretched or shrunk or removed to produce, if desired, an asymmetric dome shaped structure.

Zomes may be single or clustered.

[figure]

Figure 1.1: Zome

[figure]

Figure 1.2: Zome, with person and child

Zomes can cluster together like soap bubbles. Their zones can be stretched, shrunk, or omitted completely to make the various zomes’ different shapes and sizes. The zomes can also pack several layers deep.

[figure]

Figure 1.3: Construction of a Zome structure

[figure]

Figure 1.4: Scale model of a Zome structure

[figure]

Figure 1.5: Construction of a Zome structure

[figure]

Figure 1.6: Scale model of a Zome structure

1.2 What is the Difference Between a Zome and a Geodesic Dome?

A geodesic dome is a structure which closely follows the shape of the sphere and whose edge lengths closely follow the path of great circles on the sphere. (These are the sphere’s geodesics.) The geodesic dome, because of its shape, and the arrangement of its structural members is extremely strong, but its uses are limited because of the inflexibility of its shape. It is always part of a sphere—a low bubble or a high bubble—its floor is always a circle—any variation would destroy the structural properties of the geodesic dome. The geodesic dome, if it is large and composed of many edges and joints, has many different edge lengths. It is complicated in structure and simple in shape. Zomes are simple in structure and complicated in shape.

[figure]

Figure 1.7: Geodesic Dome—DEW line Radome, circa 1956

[figure]

Figure 1.8: Geodesic Dome

2 Zonohedra

2.1 What are Zonohedra?

A zonohedron is a convex solid, all of whose faces are polygons with edges in equal and parallel pairs.

These are possible faces for zonohedra:

[figure]

Figure 2.9: Possible faces

These are zonohedra:

[figure]

Figure 2.10: Cube

[figure]

Figure 2.11: Octagonal prism

[figure]

Figure 2.12: Rhombic Dodecahedron

[figure]

Figure 2.13: Truncated Octahedron

[figure]

Figure 2.14: Truncated Cuboctahedron

[figure]

Figure 2.15: Great rhombicosidodecahedron or Truncated icosidodecahedron

A zone of edges is a band of parallel edges which circles the solid. Every edge belongs to a zone.

[figure]

Figure 2.16: Seven-Zone Polar Zonohedron

[figure]

Figure 2.17: Polar Zonahedron from CHH Franklin’s drawing

2.2 Face Planes of Zonohedra

A plane is defined by two lines. A six-zone figure has six different lines; 1, 2, 3, 4, 5, 6. How many pairs can we form with six objects?

1,2 2,3 3,4 4,5 5,6

1,3 2,4 3,5 4,6

1,4 2,5 3,6 = 15

1,5 2,6

1,6

Table 2.1: Pairs of Six Objects

Algebraic expression:

[figure]

[figure]

Figure 2.18: Zone ‘‘1’’ shaded

[figure]

Figure 2.19: Rhombic Triconntahedron, labeled zones

Rhombic Triacontahedron with face planes labeled with numbers of the zones which form the plane.

There are then 15 more faces on the other side which add up to the 30 faces of the Triacontahedron.

The ten-zone system can form [figure] = 45 different planes.

This figure is the enneacontahedron with its faces marked:

[figure]

Figure 2.20: Enneacontahedron, labeled

The equation is for the number of planes, and if we wish to find the total number of faces for the polyhedron, including the back side, multiply the number of different planes by 2, and this equals ( n )( n − 1) .

The formula [figure] is true for the number of planes that can be formed with the different zones provided that no more than two lines lie in one plane. These collections of lines associated with zonohedra are called the stars of the zonohedra . A star is called non-singular if no three of the lines are coplanar.

If three lines of the star lie in one plane, then the zonohedron associated with the star has a pair of hexagons. If more than three lines lie in one plane, then there are facets to the zonohedron with corresponding more edges—octagon, decagon, etc.

[figure]

Figure 2.21: Singular Star, through vertices of cuboctahedron.

[figure]

Figure 2.22: Associated zonohedron, truncated octahedron

2.3 Section Stars and Face Planes

The zonohedron that has its edges parallel with the lines of the 31-zone star is a huge figure with faces—two faces for each of the 121 sections—one face on each side of the figure. The face corresponding to a particular section is formed by the lines of the star following each other head to toe around in a complete polygon. Consequently, the 242 sided zonohedron associated with the 31 zone star has:

12 regular decagons T sections

30 irregular dodecagons R sections

60 irregular hexagons S sections

20 regular hexagons V sections

60 rectangles X sections

60 rectangles Y sections

242

Table 2.2: Faces of a 31 Zone Star

[figure]

Figure 2.23: Associated face plane

[figure]

Figure 2.24: Section star

2.4 Division of Zonohedra into Parallepiped Cells

[figure]

Figure 2.25: Rhombic Dodecahedron

Every zonohedron can be divided into component parallelepiped cells. Every set of three different lines form one cell. In the case of the four-zone rhombic dodecahedron 2.25 , there are then:

[figure]

(2.1)

The sides of the component parallelepiped cells are necessarily the same as the sides of the complete figure.

[figure]

Figure 2.26: Triacontahedron

The triacontahedron subdivides into:

[figure]

(2.2)

The rhombic triacontahedron divides into 10 acute and 10 obtuse parallelepipeds.

[figure]

Figure 2.27: Enneacontahedron

The enneacontahedron subdivides into

[figure]

(2.3)

There are five different kinds of cells. With one kind of diamond, there are only two kinds of cells possible, but the enneacontahedron has two kinds of diamond faces allowing for more types of cells.

There are:

10 A cells 6 fat diamonds

acute

20 B cells 6 fat diamonds

obtuse

30 C cells 4 fat diamonds 2 skinny diamonds acute

30 D cells 4 skinny diamonds 2 fat diamonds acute

30 E cells 2 skinny diamonds 4 fat diamonds obtuse

120 cells

Table 2.3: Cells of the Enneacontahedron

3 Regular Ways of Arranging Lines in Space

The regular polyhedra are like seeds from which growths may appear. They are the connecting joints for the zonohedra. The joints are all parallel to each other. The lines of the zonohedra are perpendicular to the faces of the joints.

3.1 Three Zones

[figure]

Figure 3.28: Cube

3.2 Four Zones

[figure]

Figure 3.29: Tetrahedron

[figure]

Figure 3.30: Octahedron

[figure]

Figure 3.31: Rhombic Dodecahedron

3.3 Six Zones

[figure]

Figure 3.32: Dodecahedron

[figure]

Figure 3.33: Rhombic Triacontahedron

3.4 Ten Zones

[figure]

Figure 3.34: Icosahedron

[figure]

Figure 3.35: Rhombic Enneacontahedron

4 Clustering

4.1 Twenty-one Zone Structure

Triacontahedron

In this series, the central zome is higher. It could as well be lower.

[figure]

Figure 4.36: Triacontahedron, 1

[figure]

Figure 4.37: Triacontahedron, 2

[figure]

Figure 4.38: triacontahedron, 3

[figure]

Figure 4.39: triacontahedron, 4

[figure]

Figure 4.40: triacontahedron, 5

[figure]

Figure 4.41: triacontahedron, 5

Enneacontahedron of edge length B clustered with triacontahedron of edge length A and triacontahedron of edge length AT − 1 .

[figure]

Figure 4.42: Enneacontahedron with 2 triacontahedrons

Clusters of triacontahedra - A line vertical.

[figure]

Figure 4.43: Triacontahedra, 5

[figure]

Figure 4.44: triacontahedra, 5

4.2 Twenty-one Zone Zome Clusters

6 A LINES 15 C LINES Orientation: A lines horizontal

[figure]

Figure 4.45: Two triacontahedra fused through skew hexagon.

Two triacontahedra fused through skew hexagon.

[figure]

Figure 4.46: Front view - same as above.

[figure]

Figure 4.47: Same cluster as above - One zome has zone stretched past others.

[figure]

Figure 4.48: Three triacontahedra fused, through skew hexagon.

[figure]

Figure 4.49: Front view - same as above.

[figure]

Figure 4.50: Fourth zome added - fused to two side zomes through skew hexagon - fused to front zome through vertical section.

[figure]

Figure 4.51: Same as above. Notice the appearance of C and CT in the floor sections.

5 Stretching a Zone

Zonohedra have bands of parallel edges. Any such band of edges can be stretched to alter the shape of the zonohedron. Stretching a band of edges does not alter any angles.

[figure]

Figure 5.52: Six zone zome - half a triacontahedron

[figure]

Figure 5.53: 1 horizontal zone stretched to 2

[figure]

Figure 5.54: same as above (top view)

[figure]

Figure 5.55: 2nd horizontal zone stretched to two top panels 2x2 (top view)

[figure]

Figure 5.56: 2 side zones stretched

Stretching zones allows one to build buildings of different shapes using the same kinds of components.

[figure]

Figure 5.57:

[figure]

Figure 5.58:

[figure]

Figure 5.59:

6 Trusses: Twenty-one Zone System

6.1 6 A Lines 15 C Lines

[figure]

Figure 6.60: Single 21-zone A cell

[figure]

Figure 6.61: 2 A cells

[figure]

Figure 6.62: 4 A cells

[figure]

Figure 6.63: 8 A cells

[figure]

Figure 6.64: Truss turning corner 8 A cells

[figure]

Figure 6.65: Truss turning corner 8 A cells - 4 B cells

[figure]

Figure 6.66: Truss forming arch* A cells middle sections B cells on sides

[figure]

Figure 6.67: *Truss forming arch Head on view

[figure]

Figure 6.68: Single 21 zone B cell

21-zone truss forming a cap over 5 six-zone diamonds

[figure]

Figure 6.69:

[figure]

Figure 6.70:

[figure]

Figure 6.71:

[figure]

Figure 6.72: Six-zone truss covering the top half of triacontahedron

[figure]

Figure 6.73: Pentagonal structure formed by truncating pent corner of triacontahedron. See structure in Figure 15.162

[figure]

Figure 6.74:

[figure]

Figure 6.75: Rectangular truss - folded plate configuration

[figure]

Figure 6.76: Truss formed of obtuse cells.

[figure]

Figure 6.77:

[figure]

Figure 6.78: Two views of a rectangular trussed roof.

[figure]

Figure 6.79: Triacontahedron—with interior icosadodecahedron for stiffening.

6.2 Triacontahedron

Radius to acute angled corner = AT . Radius to obtuse angled corner = BT .

[figure]

Figure 6.80: Triacontahedron

An enneacontahedron within a triacontahedron. The six sided vertices of the enneacontahedron coincide with the three sided vertices of the triacontahedron.

[figure]

Figure 6.81: Enneacontahedron within a triacontahedron

Triacontahedron with edge = A fused with Triacontahedron with edge = AT − 1 .

Short diagonals of large diamond faces appear as long diagonals of small diamond faces.

The acute angled vertex of a large triacontahedron is located at the center of a small triacontahedron.

[figure]

Figure 6.82: Enneacontahedron within a triacontahedron

Triacontahedron clustering carried from A to AT − 2 .

[figure]

Figure 6.83: Triacontahedron

7 Critical Constants

7.1 Six Zone

[figure]

Figure 7.84: Six zone

auto

[figure]

= 1 . 0514622

[figure]

= 1 . 7013016

cos 𝜃 = 0 . 4472136

sin 𝜃 = 0 . 8944272

tan 𝜃 = 2 . 0000000

sin [figure]

= 0 . 5257310

cos [figure]

= 0 . 8506507

tan [figure]

= 0 . 6180339

7.2 Ten Zone

[figure]

Figure 7.85: Ten zone

auto

[figure]

= 0 . 7136441

[figure]

= 1 . 8683446

cos ϕ = 0 . 7453559

sin ϕ = 0 . 6666666

tan ϕ = 0 . 8944272

sin [figure]

= 0 . 3568220

cos [figure]

= 0 . 9341723

tan [figure]

= 0 . 3819660

7.3 Ten Zone

[figure]

Figure 7.86:

auto

[figure]

= 1 . 1547005

[figure]

= 1 . 6329931

cos X = 0 . 3333333

sin X = 0 . 9428090

tan X = 2 . 8284271

sin [figure]

= 0 . 8164965

cos [figure]

= 0 . 5773502

tan [figure]

= 0 . 7071067

A line radii of an icosahedron with edge = C . The pair of radii outline one end of a golden diamond.

[figure]

Figure 7.87: Six-Zone Diamond

[figure]

Figure 7.88: Golden Diamond

B line radii of dodecahedron with edge = C . One pair outlines one end of the skinny diamond; another pair outlines an end of a maraldi diamond.

[figure]

Figure 7.89: 10 Zone Diamonds

[figure]

Figure 7.90: Skinny Diamond

[figure]

Figure 7.91: Maraldi Diamond

A = 0 . 9510565 C = cos18 ° C

A = 1 . 0981855 B

B = 0 . 8660254 C = cos30 ° C

B = 0 . 9105930 A

C = 1 . 0514622 A

C = 1 . 1547005 B

Table 7.1: Proportions Of A , B , and C Lines

7.4 The Appearance of the CTn Series in the Dimensions of the Triacontahedron and the

Enneacontahedron

Both these patterns can be found as sub patterns of the five-fold symmetry patterns of page.

[figure]

Figure 7.92: Triacontahedron

All edges are A lines—one A line is perpendicular to the plane of page.

[figure]

Figure 7.93: Enneacontahedron

All edges are B lines— A line is perpendicular to the plane of page.

8 Symmetries of a Regular Thirty-one Zone Star

The dodecahedron and the icosahedron are duals of each other - the vertices of one match the face midpoints of the other and vice versa.

The ten B lines of the thirty-one zone star go through the vertices of the dodecahedron or, equivalently, the face midpoints of the icosahedron while the six A lines go through the vertices of the icosahedron or, equivalently, the face midpoints of the dodecahedron.

The fifteen C lines go through the edge midpoints of either the icosahedron or the dodecahedron.

The middles of edges are commonly midway between vertices or face midpoints and C lines bisect all angles between A lines and three of the four kinds of angles formed between B lines.

In examining angles between lines, we are also examining equators. There are six different equators and slicing through them, we form the R , S , T , V , X , and Y sections.

All pairs of lines lie in one of-these six kinds of sections.

See Sections for a discussion of different angles and the polygons they form.

[figure]

[figure]

[figure]

[figure]

[figure]

Figure 8.94: Thirty-One Zone Star: Dodecahedron

[figure]

[figure]

[figure]

[figure]

[figure]

Figure 8.95: Thirty-One Zone Star: Icosahedron

9 Five-Fold Symmetry

The icosahedron and the dodecahedron have five-fold symmetry. They cannot occur as crystals. Crystals are built up of molecules that are located in systems of regular points. It is impossible for a system of regular points to have five-fold symmetry. The inability of objects with five-fold symmetry to fit together is obvious if one tries to it regular pentagonal tiles together to cover a plane. Three, four and six sided tiles will fit, but not regular five sided tiles.

[figure]

Figure 9.96:

[figure]

Figure 9.97:

[figure]

Figure 9.98:

There do exist crystals, for example MoAl12, that contain icosahedral elements within their component cells. But only a subgroup of the icosahedron’s many symmetries is employed in the structure, and the icosahedron merely goes along for the ride. It is impossible for it to use its five-fold symmetry. The case of the icosahedral element within the MoAl12 crystal can be compared to a set of triangular tiles, each with a pentagon pattern within. But the pentagon, although it might touch a side, would leave the pattern up to the simpler shape that it lived within.

[figure]

(a) MoAl12 crystal pattern

[figure]

(b) Pediastrum species

Figure 9.99: Five Fold Symmetry Examples

Three different species of Pediastrum. (From Brown, The Plant Kingdom, Ginn, 1935 [ Bro35 ]) Note that the two on the right have five-fold symmetry.

Five-fold symmetry does appear scattered among other symmetries in nature.

9.1 Growth and Generations of Stars

Below, we have three different patterns. Each has been produced by a different star following the same rule of growth. In one case, the pattern is that of squares, in other triangles and in the largest a strange pattern of over-lapping pentagons and five pointed stars.

The rule followed is that the star sprouts other stars similar to itself at each of its end points. Each old end point must sprout before new ones sprout.

This is called recursive growth. In the first two cases, it produces a simple and uniform pattern which, as it grows, duplicates itself across the page.

The patterns to the right of the line patterns indicate at which generation the point was produced.

The regularity and homogeneity of the patterns of squares and triangles indicate the simplicity of growths that follow these symmetries. These are patterns of crystal growth—billions of identical molecules can be incorporated identically in these patterns.

In the case of the pattern with five-fold symmetry, there isn’t uniformity. Different points have different patterns in their immediate neighborhoods. Instead of the pattern simply reproducing itself across the page, it becomes steadily more intricate.

[figure]

(a) Stars

[figure]

(b) Sprouting Stars

[figure]

(c) Growth Patterns

[figure]

(d) Generations

Figure 9.100: Square Patterns

[figure]

(a) Stars

[figure]

(b) Sprouting Stars

[figure]

(c) Growth Patterns

[figure]

(d) Generations

Figure 9.101: Triangle Patterns

[figure]

(a) Stars

[figure]

(b) Sprouting Stars

[figure]

(c) Growth Patterns

[figure]

(d) Generations

Figure 9.102: Pentagon Patterns

10 Sections

If the lines of the 31-zone star followed no pattern, it would be possible to form [figure] = 465 planes—each with a different orientation.

In our 31-zone system, the pairs of lines form only 121 different planes—this is because some of the pairs of lines lie on the same plane. Thus, our 31-zone star is singular. 1 In any one 31-zone star there are:

1 See definition of singular star - Figure 2.21

15 R sections

30 S sections

6 T sections

10 V sections

30 X sections

30 Y sections

Table 10.1: Section types in 31 zone star

10.1 R Section

[figure]

Figure 10.103: R Section Star

[figure]

Figure 10.104: R Section Equators

[figure]

Figure 10.105: One R Section Equator

[figure]

[figure]

[figure]

[figure]

[figure]

[figure]

Figure 10.106: Species of R Section Triangles and Their Subdivisions 1—6

[figure]

[figure]

[figure]

[figure]

[figure]

[figure]

Figure 10.107: Species of R Section Triangles and Their Subdivisions 7—12

10.2 S Section

[figure]

Figure 10.108: S Section

[figure]

Figure 10.109: S Section Equators

[figure]

Figure 10.110: One S Section Equator

In the S section there is only one triangle possible:

[figure]

Figure 10.111: S Section Triangle

10.3 T Section

[figure]

Figure 10.112: T Section

[figure]

Figure 10.113: T Section Equators

[figure]

Figure 10.114: One T Section Equator

In the T section there are two kinds of triangles possible:

[figure]

Figure 10.115: T Section Triangles

10.4 V Section

[figure]

Figure 10.116: V Section

[figure]

Figure 10.117: V Section Equators

[figure]

Figure 10.118: V Section Equator

In the V section there are equilateral triangles:

[figure]

Figure 10.119: V Section Equilateral Triangle

10.5 X Section

[figure]

Figure 10.120: X Section

[figure]

Figure 10.121: X Section Equators

[figure]

Figure 10.122: One X Section Equator

In the X section there is a rectangle:

[figure]

Figure 10.123: X Section Rectangle

10.6 Y Section

[figure]

Figure 10.124: Y Section

[figure]

Figure 10.125: Y Section Equators

[figure]

Figure 10.126: One Y Section Equator

In the Y section there is a rectangle:

[figure]

Figure 10.127: Y Section Rectangle

10.7 The Formation of Triangles

The R , S , T , and V sections contain triangles; the X and Y don’t. They couldn’t because they don’t have enough lines. Every triangle has sides running in three different directions, but the X and Y have only two directions.

If we have three zones in one plane, then we can form a triangle. If it is a structure with only certain lengths of structural members, then we must have them proportioned correctly so that they begin and end at the vertices of these particular kinds of triangles. This is a more difficult problem. The A and B lines are unique in that stars formed of only A lines or B lines are non-singular. They define maximum numbers of planes—most uniformly distributed through space—with minimum numbers of lines. But they cannot triangulate themselves—mixed A and B lines do form triangles as can be seen in the triangles within the R sections. But it is the 15 C lines that serve as the triangulators in our star. In the T and V sections they form triangles with themselves while in the R and S sections the very relationship between the lengths of the A and B lines was determined by choosing the same C lines as a base for two different triangles—one with A lines and one with B lines.

10.8 A Star Problem

An interesting problem for the designer would be to construct a star in which every plane defined in the system by two lines could be triangulated by other lines in the system. Or, to arrange lines in space, so there were never only two lines in one plane. This is impossible—as you add more lines to triangulate a plane, the new lines define new planes with old lines, and the star needs even more new lines to form triangles. That the X and Y sections in the thirty-one zone star are unable to triangulate themselves cannot be avoided. A proof of this assertion can be derived from the necessity of all convex polyhedra to have some faces with fewer than six sides.

We have shown all the triangles that can be formed with our system. We have not illustrated all the convex polygons—those with an even number of sides are straight forward. The existence of irregular pentagons, septagons, nonagons and eleven sided figures has not been investigated.

There are a finite number of classes of such an angle similar convex polygons. If one does not insist that the polygons be convex, then there are infinite numbers of such polygons.

In three dimensions, the smallest convex polyhedron is the tetrahedron. A tetrahedron has 4 triangular sides. The stock of possible triangles to form tetrahedra is those we have shown in the R , S , T and V sections. These triangles must fit together along the proper planes to form tetrahedra within our system. For instance, in the V sections there are equilateral triangles, but the dihedral angles between V sections do not allow us to form a regular tetrahedron in our system.

11 The Divine Proportion

[figure]

Figure 11.128: Divine Proportion

THE DIVINE PROPORTION, or 1 . 6180339 … is the relationship between the diagonal of a pentagon to the edge. This accounts for its ubiquitous appearance in our structures with five-fold symmetry, for these structures are continuously forming pentagons. Again and again components can be found as diagonals or sides of pentagons made with other components—or both. But this isn’t really reason enough. It is hard to think of any of the numerous divine proportion relationships as cause for others. Rather, they all seem symptoms of a deeper set of relationships. And our fastening on the divine proportion and the Fibonacci numbers 1 seems peculiar when we consider, for instance that the square root of 2 appears again and again in grids of squares.

1 See Section 11.2

[figure]

Figure 11.129: Square root of 2

And that the square root of 2, an irrational number, is approached by a simple sequence of fractions.

[figure]

(11.1)

Each denominator is the sum of the numerator and the denominator of the preceding fraction. Each numerator is the sum of its own denominator and the preceding one. Or, if one uses a pattern of seven lines, there are still other relationships and their powers that appear and reappear.

[figure]

Figure 11.130: 7-Zone Star

In the 7-zone star the relationship between the lengths of the radii and the line 45 can be approached by the relationship between successive integers in a sequence formed in much the same way as the divine proportion’s Fibonacci series. The rule for forming the sequence is that in the sequence any integers S n :

[figure]

(11.2)

or, for example,

[figure]

(11.3)

The first terms in the sequence are…1, 2, 5, 11, 25, 56, 126, 283, 636, 1429, 3211, 7215, 16212, 36428, 81853

[figure]

(11.4)

[figure]

(11.5)

[figure]

(11.6)

[figure]

(11.7)

Calculating the value from 10 place trigonometry tables

[figure]

(11.8)

The relationship between the radius and the line 27 is approached by the ratio between adjacent terms in a sequence where:

[figure]

(11.9)

The more you examine properties of objects and phenomena, the more you find yourself presented with a few terms, usually simple, from a long series of terms. Often you cannot touch the terms which are farther or lower in the series, but you can define properties which they have. One gets the feeling of living in a container - one of an infinite number - to which are shunted objects and phenomena which have passed through one filter but can’t pass through another; a great process like that which takes place in a gravel yard, only we are unable to see gravel other than that of our own size but sense that it exists in endless different piles beyond - everything from sand to piles of planet sized boulders.

T expressed as a continued fraction.

[figure]

(11.10)

We can truncate the fraction anywhere and compute its value. The farther we carry it the closer it approximates the exact value;

[figure]

(11.11)

11.1 Tau Power Series

T − 3

0.2360680

T − 2

0.3819660

T − 1

0.6180340

T 0

1.0000000

T 1

1.6180340

T 2

2.6180340

T 3

4.2360680

T 4

6.8541020

T 5

11.0901699

T 6

17.9442719

T 7

29.0344418

Table 11.1: Tau Power Series

[figure]

(11.12)

11.2 Pattern and Rules

If you begin with any two numbers and follow the rule, each term equals the sum of the two preceding terms, the ratio between consecutive terms approaches the divine proportion.

The first two terms of the Fibonacci numbers are 1, 1, and their proportion [figure] is a long way from T , but [figure] quickly approaches T .

[figure]

(11.13)

[figure]

(11.14)

Accompanying many simple polygons and patterns of polygons are series such as the Fibonacci, where the relationships between different terms approach the precise geometric relationships. The rules for forming the accompanying series are then clues for examining the structure of the pattern. And the relationships repeated in the pattern are clues for rules which give the process to form the pattern.

The perfection of the geometric form seems fragile. If we demand perfection to 7 decimal places, the thickness of a line spoils our form.

But the rules for the formation of the series which accompany the pattern are sturdy and simple. If mistakes are made in a sequence formed by the rules, the sequence heals itself after a few generations to again approach the precise form. This is seen in how quickly the Fibonacci series approaches T after its clumsy beginning.

[figure]

Figure 11.131:

Stacks of six zone acute and obtuse cells. The widths of an acute cell and an obtuse cell are in the divine proportion. Therefore, a series of stacks can be built with each stack 1.6180339… times as tall as the one before it. The rule is that each stack is made by placing the two stacks that precede it on top of each other.

There are also numerous relationships involving the divine proportion among the altitudes of the parallelepiped cells formed with ” B ” lines.

11.3 The Fibonacci Numbers

F 1 1 F 11 89 F 21 10946 F 31 1346269

F 2 1 F 12 144 F 22 17711 F 32 2178309

F 3 2 F 13 233 F 23 28657 F 33 3524578

F 4 3 F 14 377 F 24 46368 F 34 5702887

F 5 5 F 15 610 F 25 75025 F 35 9227465

F 6 8 F 16 987 F 26 121393 F 36 14930352

F 7 13 F 17 1597 F 27 196418 F 37 24157817

F 8 21 F 18 2584 F 28 317811 F 38 39088169

F 9 34 F 19 4181 F 29 514229 F 39 63245986

F 10 55 F 20 6765 F 30 832040 F 40 102334155

Table 11.2: Fibonacci Numbers

[figure]

(11.15)

12 Coherence Proofs

In a structural system or any pattern the question arises; what is the pattern made of? What are the relationships between different elements of the pattern?

In a checkerboard pattern such as that shown in figure 9.100 all distances between neighboring intersections are the same. And the distance between two intersections of any line is simply a multiple of this base distance. This base distance then naturally becomes the unit for building the pattern.

In our pattern created by the star with five-fold symmetry, the situation is different. There are many different lengths between intersections. If the growth patterns follow simple rules such as those followed in forming the two-dimensional pattern of figure 9.102 , then all distances between intersections can be expressed as simple sums of components whose lengths are equal to powers of the divine proportion times some constant. This is also true in three dimensions - the A and B lines of the 31-zone star forming a growth similar to our 2-dimensional growth intersect each other at points where the distance between any two intersections on an A line equals

[figure]

(12.1)

and the distance between two intersections on a B line equals a polynomial

[figure]

(12.2)

The building blocks for our system are then a series of lengths related by the divine proportion. An A series, a B series and a C series—each of slightly different lengths. 1

1 See Critical Constants 7 and Hardware 15 .

12.1 Two Dimensions

12.1.1 Definition 1

We call any particular polynomial of the form

[figure]

(12.3)

s i and r i are integers.

We call the class of all such polynomials F ( kT ) then;

[figure]

(12.4)

[figure]

(12.5)

[figure]

(12.6)

We are interested in the distances between intersections along the lines of certain sets of patterns.

12.1.2 Definition 2

A pattern is a number of extended lines which point in five different directions in one plane with at least one line pointing in each direction.

[figure]

Figure 12.132:

12.1.3 Definition 3

The lines are labeled;

i l n

n = 1 , 2 , 3 , 4 , 5

i = 1 , 2 ,…

n names the direction - i names the particular line pointing in that direction. The angles between lines are;

[figure]

12.1.4 Definition 4

An intersection is named by any two of the lines which intersect there, such as

[figure]

(12.7)

12.1.5 Definition 5

If on a line all intervals between intersections are equal to different f i ( kT ) , then the intersections ‘‘fit’’ each other.

An intersection fits a line if it fits all intersections on that line.

A line g l p fits another line f l q if the intersection g l p × f l q fits all the intersections of f l q .

A pattern fits if all the intersections on all the lines fit.

Lemma 12.1.1. If on a line l n an intersection I n fits an intersection I m then I n fits all I o where I o fits I m .

Lemma 12.1.2. Any i l m , j l n , h l p , m≠n , n≠p , p form a triangle similar to T 1 or T 2

[figure]

12.1.6 Definition 6

These triangles are called the Golden triangles because their sides are in the divine proportion.

Lemma 12.1.3. If the two vertices of a Golden Triangle fit each other then all vertices fit each other.

Lemma 12.1.4. If a line j l m fits a line h l n and if all l n fit some line i l m and if i l m fits all l n without the line j l m , then, all intersections j l m × l n fit j l m × h l n and the line j l m fits all l n .

[figure]

Figure 12.133:

Lemma 12.1.5. If j l m fits h l n then all l p , p≠m , n × j l m fit jlm × hln and if h l n fits all l p without j l m them j l m fits all l p .

Theorem 12.1.6. If a pattern fits and a line j l m is added and j l m fits some line j l n ,n≠m , then the new pattern including j l m fits.

A pattern fits if all the intersections on all the lines fit. (Definition 5) To prove the new pattern fits we must prove all the new intersections fit the lines they are on.

There are no new intersections on the lines k l m ,k≠j , therefore all the intersections on these lines fit.

All the intersections j l m × l n fit j l m × h l m and the line j l m × h l m and the line j l m fits all l n . (Lemma 4) Therefore all the intersections of the lines l n fit.

All the intersections l p,p≠m,n × j l m fit j l m × h l n . (Lemma 5) Therefore, the intersections of line j l m fit j l m × h l n . Therefore, the intersections fit on all the lines l m (step 1) and j l m fits all l p,p≠m,n (Lemma 5) which means that all the intersections on all the lines l p,p≠m,n fit and our theorem is thus proved.

12.2 Three Dimensions

12.2.1 Definition 1

In three dimensions we have a pattern made up of the diameter lines through vertices and face midpoints of the icosahedron.

The lines through the vertices are the A lines.

The lines through the face midpoints lines are B lines.

There can be other lines parallel to the original 16 lines. They are given the name of the line they are parallel to.

We name a line

i A n 1

n = 1 , 2 , 3 , 4 , 5 , 6

i = 1 , 2 ,…

j B m 1

m = 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10

j = 1 , 2 ,…

or generally

h X i p 1

p = 1 , 2 … 10

h = 1 , 2 ,…

X = A,B

12.2.2 Definition 2

All lines of a 3D pattern are connected directly or through other intersections to the original pattern of 16 lines.

12.2.3 Definition 3

Intersections on A lines ‘‘fit’’ if all the intervals between them can be expressed as polynomials

[figure]

(12.8)

s i ,r i = integers and A = an interval of length.

12.2.4 Definition 4

Intersections on B lines ‘‘fit’’ if all intervals between them can be expressed as polynomials.

[figure]

(12.9)

s i ,r i = integers and B = an interval of length.

12.2.5 Definition 5

[figure]

(12.10)

12.2.6 Definition 6

A 3D pattern ‘‘fits’’ if all the intersections on all the lines fit.

12.2.7 Definition 7

An R section is a plane containing two A lines and two B lines. The angle between the two A lines is 𝜃 ; the angle between the two B lines is ϕ ; the angle between an A and a B line is

[figure]

(12.11)

12.2.8 Definition 8

A T plane is a plane perpendicular to an A line. A T plane is named by this A line

[figure]

Lemma 12.2.1. There are five R sections perpendicular to each T plane. Each A line is contained in five different R sections. Each B line is contained in three different R sections.

Lemma 12.2.2. The projection of the interval A along any A line onto a T plane

[figure]

(12.12)

12.2.9 Definition 9

[figure]

(12.13)

Unsure: What does 0.A resolve to? (if the interval is on the A line perpendicular to the T plane).

Lemma 12.2.3. The projection of the interval B along any B line onto a T plane

[figure]

(12.14)

[figure]

Figure 12.134:

Lemma 12.2.4. The projection onto any T plane of any interval along any line k X i r 1 between any two intersections which fit in the 3D pattern is a polynomial

[figure]

(12.15)

s i ,r i = integers

k = A sin( 𝜃 ) = B sin( [figure] )

Lemma 12.2.5. The angles between the lines projected on a T plane are

[figure]

(12.16)

[figure]

Figure 12.135:

Lemma 12.2.6. 3D Patterns which fit project onto all T planes 2-dimensional patterns which fit.

Lemma 12.2.7. All intervals between intersections of lines of the 3D pattern appear as intervals between intersections in the projections on some T planes.

For an intersection

[figure]

(12.17)

not to appear as an intersection in the pattern projected on a T plane, the intersecting lines must lie in one of the five perpendicular R sections.

At most, two different lines intersect i X k n l . The two intersections

[figure]

lie. Therefore, there is at least one T plane in which both 3D intersections project as 2-dimensional intersections.

Lemma 12.2.8. If some pairs of intersections

[figure]

(12.18)

did not fit in our 3D pattern, that is, we cannot find any polynomial f 1 ( X k T ) that equals the interval between them, then also for some T plane we cannot find a polynomial f i ( kT ) which equals the interval between their projected intersections.

Lemma 12.2.9. Any misfits between intersections of the 3D pattern project as misfits between intersections on some T plane. Therefore, a 3D pattern which projects on all T planes as a 2D Pattern which fits is a 3D pattern which fits.

Theorem 12.2.10. If a 3D pattern fits and a new line is added k X i n l which intersects and fits some other line h X j n l then the new 3D pattern including k X i n l fits.

Proof. In each T plane the projection of the line k X i n l fits the projection of the line h X j m l . In each T plane the projection of the 3D pattern without k X i n l fits. Therefore, the projection is with the line k X i n l fits on each T plane and the theorem is proved. □

The coherence proof demonstrates that if one builds a structure using the A and B lines of the 31 zone star (the C lines may be used only within the forms defined by the A and B lines) and always follows the rule that new parts are added at intersections of existing parts or at points along existing parts which can be reached by subdividing a large part into component small parts, then no matter how far or intricately one builds, two extensions of two entirely different limbs of the same structure can always be locked back together in a perfect fit with a combination of our simple parts.

We have shown that the intervals between intersections are all equal to certain polynomials in T . Because

[figure]

(12.19)

all the terms of any such polynomial can descend by subdivisions into a polynomial with only two terms-

[figure]

(12.20)

There are many interesting side-lights to these investigations. One of which is that it is impossible to divide any one of our building blocks AT n into equal pieces.

There are much shorter proofs of the coherence of this system, but the short proofs don’t lead one through so many characteristics of the structure.

13 Joints

We have associated the thirty-one zone star throughout with the icosahedron and the dodecahedron. It also fits perfectly with the three smaller regular polyhedra. The tetrahedron, the cube and the octahedron fit inside the icosahedron and the dodecahedron. Their vertices touch a vertex, an edge midpoint or a face midpoint of the larger figure. This regular match between large and small figure positions the smaller figure so that regular patterns on the large figure project inwards as regular patterns on the small figure. In each case, either five or ten small figures fit at once within the larger figure. 1 Each of the regular polyhedra is thus a convenient core from which to define the regular thirty-one zone star. The geometric regularities insure simplicity in the connections. Any one of the regular polyhedra can be used with the same pattern of flanges or holes on each of its faces as a connector for the thirty-one zone structural system. 2

1See illustrations in Cundy and Rollet’s Mathematical models [ CR61 ].

2 Note! In the case of the thirty-one zone pattern projected on the octahedron, four of the faces have a left-handed pattern. The drawing and the photo are of patterns with different handedness.

[figure]

Figure 13.136: Tetrahedron

[figure]

Figure 13.137: Tetrahedron Vertices

[figure]

Figure 13.138: Cube

[figure]

Figure 13.139: Cube Vertices

[figure]

Figure 13.140: Octahedron

[figure]

Figure 13.141: Octahedron Vertices

[figure]

Figure 13.142: Dodecahedron

[figure]

Figure 13.143: Dodecahedron Vertices

[figure]

Figure 13.144: Icosahedron

[figure]

Figure 13.145: Icosahedron Vertices

14 The Stars of Other Systems

In the design of a connector simplicity in one part may demand specialization and the establishment of hierarchies among other parts.

The sketches of a joint of an icosahedron show examples of different ways of joining the five edges of an icosahedron. The parts remain identical if they trade or share with each other at the joint.

[figure]

Figure 14.146: Sharing

[figure]

Figure 14.147: Trading

When some parts dominate others, there is a hierarchy created and the parts must be differentiated. In our illustration, we show five edges of an icosahedron stacked on top of one another. With the icosahedron, it is possible to have both ends of each edge occupy similar positions, but this is not always true.

[figure]

Figure 14.148: Dominating

The creation of one hierarchy may create the need for more. For instance, if you wish to use a hierarchy of stacked edges to make a simple triangle, then you must also create a hierarchy between ends of the same edge. The two ends of the same edge have different ranks.

[figure]

Figure 14.149: Stacked Edges of a Triangle

Very often we don’t have the structural members actually touching each other. Then we avoid the edges’ problem of sharing, trading or dominating—we push the entire problem on to the joint. The joint must accommodate all the connecting members, and it shouldn’t demand that they have elaborate ends or different kinds of ends. The joint must also be strong and inexpensive.

If the joint is a ball and the A , B and C connections are simply holes which the members screw into. All holes of the same type are identical, and the ends of all structural members are identical.

This is a wonderful feature because you can’t make mistakes—there are no right and wrong holes of a certain type. The joint shown in Figure 15.160 has 12 threaded holes for the A lines in the thirty-one zone system. Joints made this way are expensive, and the connectors at the end of the structural members are expensive. A common inexpensive connecting system is a joint made of multiple interconnecting flanges with the flattened ends of the structural members bolting against the flange of the joint. Joints made of flanges can be simple flat stampings that lock together or are welded together.

Flanges bring problems. What if you must connect two joints, and you find that once you bolt one end of your member to one joint it can’t bolt to the other because the flange is turned the wrong way? The specialization of a flat end and a flange has brought problems. The end of the structural member could be made to swivel. That is expensive. The joint could be made so that this problem never arises. Unfortunately, our second solution is not always possible. To make a thirty-one zone joint where each connection is a flat flange and which is impossible to put together incorrectly, you have to devise a pattern that passes through each connecting point only once and is regular (you can’t tell the pattern that surrounds a connection from the pattern that surrounds any other connection of the same type).

[figure]

Figure 14.150: Flanges of an icosahedron or dodecahedron

This is impossible to do in the case of the thirty-one zone star. You can make a flange joint for the thirty C connections. The C lines can have the specialization of flange orientation while still avoiding the clumsiness of having to arrange themselves in a hierarchy. The flanges are the edges of an icosahedron or a dodecahedron.

Three interlocking rectangles at right angles to each other form a flange joint for the 12 A lines, 6 C lines and 12 B lines.

[figure]

Figure 14.151: Interlocking rectangles forming a flange joint

Note! These are three perpendicular R sections.

There is a mistake proof flange joint for both A and C connections if one hierarchy is introduced. You must always orient the joint to suit the A lines.

This joint is shown in the photo of the wooden model of the three intersecting planes.

[figure]

Figure 14.152: Model of intersecting planes

Two of the flanges for the missing C lines are added. This joint is completely regular until the addition of these C flanges—they are not in the same plane as their neighboring A flanges. We thus have two types and lose our regularity.

A good flange joint for the thirty-one zone star is made of six interlocking disks—five R sections and one T section.

[figure]

Figure 14.153: Six interlocking disks

[figure]

Figure 14.154: Vertices on a sphere

This creates an irregular icosahedron which passes through each of the sixty-two connecting points and decides automatically the orientation of sixty of the flanges. The pole points of this figure are A connections and one of the five intersecting R sections must dominate the others to determine the flange orientation. This joint can have part or all of the R sections in place depending on which connections are needed.

14.1 Octet Truss

The widely used octet truss is based on the star that passes through the midpoints of the edges of a cube. (Or, equivalently, the midpoints of the edges of an octahedron, the midpoints of the faces of a rhombic dodecahedron, the vertices of a cuboctahedron.)

[figure]

Figure 14.155: Star for octet truss

This is a singular star with four sections ( A sections in drawing) containing three lines at 60 ° to each other and three sections with two lines at right angles ( B sections). The zonohedron whose edges are parallel to the lines of the star is the truncated octahedron.

[figure]

Figure 14.156: Truncated Octahedron

14.2 The Mero Space Grid System

This system is based on the octet truss star plus three more zones which pass through the face midpoints of the cube which has the other lines passing through its edge midpoints. This singular star has three sections ( B sections) with four lines intersecting at 45 ° to each other, four sections ( A sections) with three lines at 60 ° to each other and six sections ( C sections) with two lines at 90 ° to each other.

[figure]

Figure 14.157: Star for MERO system

The zonohedron associated with this star is the truncated cuboctahedron.

[figure]

Figure 14.158: Truncated Cubooctahedron

15 Hardware

[figure]

[figure]

[figure]

[figure]

Lengths of A , B , and C lines.

Structural members where A = 40 ′′ .

[figure]

Figure 15.159: Six Zone Joint Plan

[figure]

Figure 15.160: Six Zone Joint

[figure]

Figure 15.161: Section for 1 1 ⁄ 4 ’’ pipe

[figure]

Figure 15.162: Framework for Robert Ford residence.

A lines = AT 2 ; base A = 40 ′′

C lines = CT 2 (see page 32)

[figure]

Figure 15.163: Zome Climber

A lines = 40 ′′ C lines = 42 ′′

List of Figures

1.1 Zome 1.2 Zome, with person and child 1.3 Construction of a Zome structure 1.4 Scale model of a Zome structure 1.5 Construction of a Zome structure 1.6 Scale model of a Zome structure 1.7 Geodesic Dome—DEW line Radome, circa 1956 1.8 Geodesic Dome 2.9 Possible faces 2.10 Cube 2.11 Octagonal prism 2.12 Rhombic Dodecahedron 2.13 Truncated Octahedron 2.14 Truncated Cuboctahedron 2.15 Great rhombicosidodecahedron or Truncated icosidodecahedron 2.16 Seven-Zone Polar Zonohedron 2.17 Polar Zonahedron from CHH Franklin’s drawing 2.18 Zone ‘‘1’’ shaded 2.19 Rhombic Triconntahedron, labeled zones 2.20 Enneacontahedron, labeled 2.21 Singular Star, through vertices of cuboctahedron. 2.22 Associated zonohedron, truncated octahedron 2.23 Associated face plane 2.24 Section star 2.25 Rhombic Dodecahedron 2.26 Triacontahedron 2.27 Enneacontahedron 3.28 Cube 3.29 Tetrahedron 3.30 Octahedron 3.31 Rhombic Dodecahedron 3.32 Dodecahedron 3.33 Rhombic Triacontahedron 3.34 Icosahedron 3.35 Rhombic Enneacontahedron 4.36 Triacontahedron, 1 4.37 Triacontahedron, 2 4.38 triacontahedron, 3 4.39 triacontahedron, 4 4.40 triacontahedron, 5 4.41 triacontahedron, 5 4.42 Enneacontahedron with 2 triacontahedrons 4.43 Triacontahedra, 5 4.44 triacontahedra, 5 4.45 Two triacontahedra fused through skew hexagon. 4.46 Front view - same as above. 4.47 Same cluster as above - One zome has zone stretched past others. 4.48 Three triacontahedra fused, through skew hexagon. 4.49 Front view - same as above. 4.50 Fourth zome added - fused

to two side zomes through skew hexagon - fused to front zome through vertical section. 4.51 Same as above. Notice the appearance of C and CT in the floor sections. 5.52 Six zone zome - half a triacontahedron 5.53 1 horizontal zone stretched to 2 5.54 same as above (top view) 5.55 2nd horizontal zone stretched to two top panels 2x2 (top view) 5.56 2 side zones stretched 5.57 5.58 5.59 6.60 Single 21-zone A cell 6.61 2 A cells 6.62 4 A cells 6.63 8 A cells 6.64 Truss turning corner 8 A cells 6.65 Truss turning corner 8 A cells - 4 B cells 6.66 Truss forming arch* A cells middle sections B cells on sides 6.67 *Truss forming arch Head on view 6.68 Single 21 zone B cell 6.69 6.70 6.71 6.72 Six-zone truss covering the top half of triacontahedron 6.73 Pentagonal structure formed by truncating pent corner of triacontahedron. See structure in Figure 15.162 6.74 6.75 Rectangular truss - folded plate configuration 6.76 Truss formed of obtuse cells. 6.77 6.78 Two views of a rectangular trussed roof. 6.79 Triacontahedron—with interior icosadodecahedron for stiffening. 6.80 Triacontahedron 6.81 Enneacontahedron within a triacontahedron 6.82 Enneacontahedron within a triacontahedron 6.83 Triacontahedron 7.84 Six zone 7.85 Ten zone 7.86 7.87 Six-Zone Diamond 7.88 Golden Diamond 7.89 10 Zone Diamonds 7.90 Skinny Diamond 7.91 Maraldi Diamond 7.92 Triacontahedron 7.93 Enneacontahedron 8.94 Thirty-One Zone Star: Dodecahedron 8.95 Thirty-One Zone Star: Icosahedron 9.96 9.97 9.98 9.99 Five Fold Symmetry Examples 9.100 Square Patterns 9.101 Triangle Patterns 9.102 Pentagon Patterns 10.103 R Section Star 10.104 R Section Equators 10.105 One R Section Equator 10.106 Species of R Section Triangles and Their Subdivisions 1—6 10.107 Species of R Section Triangles and Their Subdivisions 7—12 10.108 S Section 10.109 S Section Equators 10.110 One S Section Equator 10.111 S Section Triangle 10.112 T Section 10.113 T Section Equators 10.114 One T Section Equator 10.115 T Section Triangles 10.116 V Section 10.117 V Section Equators 10.118 V Section Equator 10.119 V Section Equilateral Triangle 10.120 X Section 10.121 X Section Equators 10.122 One X Section Equator 10.123 X Section Rectangle 10.124 Y Section 10.125 Y Section Equators 10.126 One Y Section Equator 10.127 Y Section Rectangle 11.128 Divine Proportion 11.129 Square root of 2 11.130 7-Zone Star 11.131 12.132 12.133 12.134 12.135 13.136 Tetrahedron 13.137 Tetrahedron Vertices 13.138 Cube 13.139 Cube Vertices 13.140 Octahedron 13.141 Octahedron Vertices 13.142 Dodecahedron 13.143 Dodecahedron Vertices 13.144 Icosahedron 13.145 Icosahedron

Vertices 14.146 Sharing 14.147 Trading 14.148 Dominating 14.149 Stacked Edges of a Triangle 14.150 Flanges of an icosahedron or dodecahedron 14.151 Interlocking rectangles forming a flange joint 14.152 Model of intersecting planes 14.153 Six interlocking disks 14.154 Vertices on a sphere 14.155 Star for octet truss 14.156 Truncated Octahedron 14.157 Star for MERO system 14.158 Truncated Cubooctahedron 15.159 Six Zone Joint Plan 15.160 Six Zone Joint 15.161 Section for 1 1 ⁄ 4 ’’ pipe 15.162 Framework for Robert Ford residence. 15.163 Zome Climber

• Document

List of Tables

2.1 Pairs of Six Objects 2.2 Faces of a 31 Zone Star 2.3 Cells of the Enneacontahedron 7.1 Proportions Of A , B , and C Lines 10.1 Section types in 31 zone star 11.1 Tau Power Series 11.2 Fibonacci Numbers

• Document

Bibliography

Baer, Steve - The Dome Cookbook - Lama foundation, New Mexico - 1968

Borrego, John - Space Grid Structures (Skeletal Frameworks and Stressed-Skin Systems) - MIT Press - Massachusetts - 1968

An exhaustive study of a few simple kinds of space grids with excellent illustrations of both the geometries and the hardware.

Courant and Robbins - What is Mathematics? (An elementary approach to ideas and methods) - Oxford University Press 1941 & 1953

A good book for anyone who thinks about curious and profound questions in mathematics. It has a good section on continued fractions and infinite series.

Coxeter, H. S. M. - Regular Polytopes - The MacMillan Co. New York - 1948 & 1963

This book has the most information about the regular polyhedra that I have seen. It is a difficult book for beginners. It has a good section on zonohedra. There are interesting historical remarks at the chapter ends.

Cundy and Rollett - Mathematical Models - Oxford at the Clarendon Press - 1951 & 1961

A good simple book on polyhedra and interesting mathematical models. The illustrations are the best that can be found.

Hilbert, David and S. Cohn-Vossen - Geometry and the Imagination - Chelsea Publishing Co. - New York - 1952

Many interesting and varied subjects are covered in this book. An excellent chapter on regular systems of points.

Hoggatt, Verner E. Jr, - Fibonacci and Lucas Numbers - Houghton Mifflin Co. - Boston - 1969

Short clear text. The best of the books on Fibonacci numbers.

Kowalewski, Dr. Gerhard - Per Keplersche Korper und Andere Bauspiele - K. F. Koehlers Antiquarium - Leipzig 1938

An account of the triacontahedron including the appearance of the divine proportion in its measurements, its breakdown into 20 parallelepipeds, the plaiting of its faces and ways of coloring its faces.

Ogilvy and Anderson - Excursions in Number Theory - Oxford University Press , New York - 1966

An excellent book on number theory with a lucid chapter about continued fractions.

Thompson, D’Arcy - On Growth and Form (Vol. 2) - Cambridge at the University Press - 1942 & 1963

Thompson discusses the divine proportion and the Fibonacci numbers and their appearance in nature.

Tyng, Anne Griswold - Geometric Extensions of Consciousness - English translation from ’’Zodiac 19’’ magazine -

Filled with profound observations and important structural ideas.

Vorobyov, N. N. - The Fibonacci Numbers - D. C. Heath & Co. Boston - 1963

Short clear text.

Wachsmann, Konrad - The Turning Point of Building - Reinhold Publishing Corporation, New York - 1961

An excellent book about prefabrication, design, joints, panels and processes associated with the machine.

References

[Bro35]

William Henry Brown. The plant kingdom: a textbook of general botany . Boston: Ginn and company, 1935.

[CR61]

H. Martyn Cundy and A. P. Rollett. Mathematical models . 2d ed. Oxford: Clarendon Press, 1961.