Saturday, August 15, 2020

A STEM Project: Constructing Da Vinci's Divine Proportion Polyhedra Models - Part 1 of 2

Plate I - Plate XVIII of Da Vinci's Polyhedra Models

Plate XIX - Plate XXX of Da Vinci's Polyhedra Models

An example of one of Da Vinci's drawings.

Leonardo Da Vinci was a student of Luca Pacioli, an Italian mathematician. As a student, Da Vinci illustrated a book for his teacher called “De Divina Proportione” which means "On the Divine Proportion" in 1498. The book can be viewed online at the Open Library Organization website.

In this book, Pacioli writes about the mathematics of proportions in polyhedra and the golden ratio. The golden ratio is a value equal to about 1.618. It is based on a line which is divided into two segments and the ratios of the segments are calculated.  The result produces the golden ratio value; it is also known as Phi.  Given a line with a length of 1, divide the line at a point as shown below:


 Phi, 1.618, is a number which appears frequently in nature and our eye is used to seeing this value. The dodecahedron and icosahedron have golden ratios in their dimensions.  A fun movie to watch explaining golden ratios is the Disney movie, Donald in Mathmagic Land (1959).  Here is a link to the movie on Youtube. https://www.youtube.com/watch?v=U_ZHsk0-eF0&t=418s The explanation starts at 7:00.

Leonardo Da Vinci drew fifty nine polyhedra models.  The first thirty will be included in this blog post and the remaining twenty nine polyhedra models will be in the next blog posting which is https://papercraftetc.blogspot.com/2020/08/a-stem-project-constructing-da-vincis_21.html

Here is the PDF. I used 65lb. cardstock.

Here is the .Studio file.

Here is the SVG.

I duplicated Da Vinci's drawings by constructing three-dimensional paper models. In my description of each polyhedron, I will give the side length measure and describe each model based on the number of faces, edges and vertices using Euler's formula.  For any convex polyhedron, the number of vertices and faces together is exactly two more than the number of edges.   Vertices + Faces - Edges = 2

A face is a flat, two-dimensional surface that serves as one side of a polyhedron.

An edge is a line segment where two faces meet.

Vertices is the plural of vertex.  Vertices are corner points which are formed by the intersection of faces.


Plate I, II - Solid & Hollow Plane Tetrahedron

Side Length of 3 inches
Faces
4 equilateral triangles
Edges
6
Vertices
4


Plate I - Solid Plane Tetrahedron

Plate II - Hollow Plane Tetrahedron

Plate III, IV - Solid & Hollow Truncated Tetrahedron


Side Length of 1 inch
Faces
4 equilateral triangles, 4 hexagons
Edges
18
Vertices
12

Plate III - Solid Truncated Tetrahedron

Plate IV - Hollow Truncated Tetrahedron

Plate V, VI - Solid & Hollow Elevated Tetrahedron


Side Length of 1.618 inches
Faces
12 equilateral triangles
Edges
18
Vertices
8

Plate V - Solid Elevated Tetrahedron

Plate VI - Hollow Elevated Tetrahedron

Plate VII, VIII - Solid & Hollow Plane Hexahedron or Cube

Side Length of 1.618 inches
Faces
6 squares
Edges
12
Vertices
8

Plate VII - Solid Plane Hexahedron or Cube

Plate VIII - Hollow Plane Hexahedron or Cube

Plate VIIII, X - Solid & Hollow Truncated Cube

Side Length of 1.618 inches 
Faces
6 squares, 8 equilateral triangles
Edges
24
Vertices
12

Plate IX - Solid Truncated Cube

Plate X - Hollow Truncated Cube

Plate XI, XII - Solid & Hollow Elevated Cube

Side Length of 1.618 inches
Faces
24 equilateral triangles
Edges
36
Vertices
14

Plate XI - Solid Elevated Cube

Plate XII - Hollow Elevated Cube


Plate XIII, XIV - Solid & Hollow Elevated Truncated Cube


Side Length of 1.618 inches
Faces
6 quadrilateral pyramids and 8 triangular pyramids which form to make 48 equilateral triangle faces
Edges
72
Vertices
26

Plate XIII - Solid Elevated Truncated Cube

Plate XIV - Hollow Elevated Truncated Cube

Plate XV, XVI - Solid & Hollow Plane Octahedron


Side Length of 1.618 inches
Faces8 equilateral triangles
Edges12
Vertices6

Plate XV - Solid Plane Octahedron 

Plate XVI - Hollow Plane Octahedron 

Plate XVII, XVIII - Solid & Hollow Truncated Octahedron


Side Length of 1.618 inches
Faces
8 hexagons, 6 squares
Edges
36
Vertices
24

Plate XVII - Solid Truncated Octahedron 

Plate XVIII - Hollow Truncated Octahedron 

Plate XIX, XX - Solid & Hollow Elevated Octahedron


Side Length of 1.618 inches
Faces
24 equilateral triangles
Edges
36
Vertices
14

Plate XIV - Solid Elevated Octahedron 

Plate XX - Hollow Elevated Octahedron 

Plate XXI, XXII - Solid & Hollow Plane Icosahedron


Side Length of 1.618 inches
Faces
20 equilateral triangles
Edges
30
Vertices
12

Plate XXI - Solid Plane Icosahedron

Plate XXII - Hollow Plane Icosahedron

Plate XXIII, XXIV - Solid & Hollow Truncated Icosahedron


Side Length of 1.618 inches
Faces
20 hexagons, 12 pentagons
Edges
90
Vertices
60

Plate XXIII - Solid Truncated Icosahedron

Plate XXIV - Hollow Truncated Icosahedron

Plate XXV, XXVI - Solid & Hollow Elevated Icosahedron - aka Great Stellated Dodecahedron



Side Length of 1.618 inches

Faces
60 equilateral triangles
Edges
90
Vertices
32

Plate XXV - Solid Elevated Icosahedron

Plate XXVI - Hollow Elevated Icosahedron

Plate XXVII, XXVIII - Solid & Hollow Plane Dodecahedron


Side Length of 1.618
Faces
12 pentagons
Edges
30
Vertices
20
Plate XXVII - Solid Plane Dodecahedron 

Plate XXVIII - Hollow Plane Dodecahedron 

Plate XXIX, XXX - Solid & Hollow Truncated Dodecahedron


Side Length of 1.618 inches
Faces
12 pentagons, 20 equilateral triangles
Edges
60
Vertices
30

Plate XXIX - Solid Truncated Dodecahedron 

Plate XXX - Hollow Truncated Dodecahedron

2 comments:

  1. Hello,
    These are wonderful, thank you for posting. I was wondering if the svg file could be split into two files perhaps, my computer is having difficulty opening such a large file.
    Thank you!

    ReplyDelete
    Replies
    1. I have provided a PDF of the file. You can convert the PDF to an SVG.

      Delete