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Tessellation s

Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

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Page 1: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Tessellations

Page 2: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate.The pattern that is formed is called a tessellation.

Simply put: A tessellation is like a puzzle that repeats a particular pattern.

For example:

What is a tessellation?

Page 3: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

In nature and life, they appear often:

Honeycombs...

Mud flats...

In games, like checkers..

Page 4: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Tessellations in Nature

snake skin

armadillo armorspider web

Page 5: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Tessellations are all around us:

Look for tessellations in walls, patios and pavements.

Page 6: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Tessellations are all around us:

Common shapes can be arranged in unusual ways

Sometimes an unusual shape will tessellate

Page 7: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Tessellations are all around us:

Sometimes 2 or more different shapes will tessellate.

Page 8: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Tessellations Around the House

• Tessellations can be found in quilts, floor tiling, and wallpaper.

Page 9: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

X-ray Crystallography

This picture depicts the transformation of eight points in an array to make a very small crystal lattice, which tessellates.

Study of Science

Page 10: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

This image suggests the relationship between tessellations, symmetry, and x-ray crystallograpy.

more science….

Page 11: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Hydrogen Peroxide, among other chemicals, has this tessellating, crystal structure.

and even more science….

Page 12: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Math in Tessellations• Many different geometric shapes can be

used to create tessellations.

• Which of the shapes below would fit with itself to make a good tessellation design?

Page 13: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

The mathematics of the Regular Tessellation...

• A regular polygon tessellation is constructed from regular polygons.

• Regular polygons have equal sides and equal angles.

• The regular polygons must fill the plane at each vertex, with repeating patterns and no overlapping pieces.

Note: this pentagon does not fit into the vertex… therefore it is not a regular tessellation.

Page 14: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

• Which other regular polygons do you think can tile the plane?

Regular tiling

Page 15: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

• Triangle?

Triangles

• The interior angle of every equilateral triangle is 60º. If we sum the angles around a vertex, we get 60º + 60º + 60º + 60º + 60º + 60º = 360º again!.

• Yep!• How many triangles to make 1 complete rotation?

Page 16: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

• Will pentagons work?

Pentagons

• The interior angle of a pentagon is 108º, and 108º + 108º + 108º = 324º.

Page 17: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

• Hexagons?

Hexagons

• The interior angle is 120º, and 120º + 120º + 120º = 360º.

• How many hexagons to make 1 complete rotation?

Page 18: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

• Heptagons? Octagons?

Heptagons

• Not without getting overlaps. In fact, all polygons with more than six sides will overlap.

Page 19: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

• So, the only regular polygons that tessellate the plane are triangles, squares and hexagons.

• That was an easy game. Let’s make it a bit more rewarding.

Regular tiling

Page 20: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

A famous mathematician, Kepler studied tessellations and noted the regular tessellations or (tilings) of the plane.

There are only three regular tessellations;

one of triangles

one of squares

and one of hexagons.

Page 21: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

This is NOT a regular polygon tessellation,because...

The plane is not filled at the vertex, because there is space left over.

vertex

space

A regular polygon tessellation, can be changed using “alterations” to the sides of the polygon. These alterations are called transformations.

Page 22: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Three Common Transformations

1. Translation, which is a slide of one side of the polygon.

2. Reflection, which is a flip or mirror image of one side of the polygon.

3. Rotation, which is a turn of a side around one vertex of the polygon.

Page 23: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Translations - a slide

moves here

Get practice template and try creating a translation….

the alteration

this side

Page 24: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Let’s try together….. a translation or slide….

Page 25: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Reflections - mirror images

flipshere

the alteration

Get practice template and try creating a reflection….

Page 26: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Let’s try together….. a reflection, flip or mirror image

Page 27: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Rotations - turns

the alteration

rotates aroundthis vertex

Get practice template and try creating a rotation...

here

Page 28: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Let’s try together….. a rotation or turn

Page 29: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Tessellations by M.C. Escher

Page 30: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Make Your Own Escher Tessellations 1

Step 1: Start with a simple shape that will tessellate e.g. a rectangle.

Step 2: Remove a shape or shapes from one side of the rectangle and fix them to the opposite side.

Page 31: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Make Your Own Escher Tessellations 1

Use this as a template to create your tessellation.

Page 32: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Make Your Own Escher Tessellations 2

You could start with a hexagon and cut semi-circles from three of the sides and fix them to the opposite sides like this.

Page 33: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Make Your Own Escher Tessellations 2

Page 34: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Make Your Own Escher Tessellations 3

Start with a square and cut segments from two sides and fix them to the opposite sides like this.

Page 35: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Make Your Own Escher Tessellations 3

Page 36: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Professional Tessellation Designs

• Many artists have created master works of art using the simple rules of tessellations.

• M.C. Escher and Robert Ingalls are among many tessellation artists.

• Can you you spot the repeating shape?

Sun and Moon

M.C. Escher

Fish

Robert Ingalls

Page 37: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

You Can Be a Tessellation Artist

You need to first create a tessellating template.• Step 1: using grid paper cut out a perfect square. • Step 2: with a pencil make a line on two adjacent

sides of the square. Be sure not to draw through a corner.

• Step 3: cut out the pieces and attach them with tape to the opposite sides from where they came.

You have now created your tessellation template.

Page 38: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Seeing a Figure• Looking at your tessellation template, study

the sides and the shape to decide what sort of figure you might see.

• The person who designed this form saw an elephant and an elf.

• Are there any other different forms that you might see?

• When looking for the shape be sure not to see too much detail as it can make the art work too crowded.

Page 39: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Putting It All Together• Take your

tessellation template and trace it on to a piece of paper.

• When tracing you can use different types of symmetry to change your picture.

• Be sure that your whole page is filled with a repeating pattern.

• Colour in your picture creatively.

Elephants

Translation symmetry

Elves and Elephants

Combinations of symmetry

Page 40: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Is this a regular tessellation?

What kind of tessellation is this?

Extras ...

Constructing tessellations - Claris/Appleworks, HyperCard, HyperStudio, Geometry Sketchpad, Windows Paint and more.

Tessellation internet activity

Cool site for interactive Javascript tessellations.

Page 41: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

• Totally Tessellated - ThinkQuest winner - great site, instruction, information. http://library.advanced.org/16661/

• Tessellations Tutorials - Math Forum sitehttp://forum.swarthmore.edu/sum95/suzanne/tess.intro.html - site for construction of tessellations. http://forum.swarthmore.edu/sum95/suzanne/links.html - great list of tessellation links

• World of Escher site - commerical site with gallery of Dutch artist,Escher who was famous for his tessellation art.http://WorldOfEscher.com/gallery/

• Science University’s Tilings Around Us Site. http://www.ScienceU.com/geometry/articles/tiling/tilings.html

The end ...

• Other links from Forum.http://forum.swarthmore.edu/library/topics/transform_g/

Links

• Math. Com - List of good tessellation linkshttp://test.math.com/students/wonders/tessellations.html

Page 42: Tessellations If many copies of a shape can be used to cover a surface, without leaving any gaps between them, then we say that the shape will tessellate

Paper Folding Movie

Click to play the movie.