520 likes | 1.05k Views
Kolam – Artwork of India. Rotational Symmetry Updated Fall 2012. Tamil Threshold Designs. Flour in right hand, women drop flour/stone to make a curve through thumb and pointer finger.
E N D
Kolam – Artwork of India Rotational Symmetry Updated Fall 2012
Tamil Threshold Designs Flour in right hand, women drop flour/stone to make a curve through thumb and pointer finger. “The Indian ritual of creating rice Kolam at the start of each day has been passed on from mother to daughter for thousands of years.”
The pattern normally starts with putting the dots as follows: . … ….. ……. ….. … . Women make a curve around the dots.
Kolam Example #1 http://www.tamilnation.org/images/culture/kolam/kolam5.jpg
Kolam Example #1 Rotational symmetry at 90, 180, and 270. Smallest angle of rotation is shown. (picture taken slightly off center)
Kolam Example #2 http://www.kamat.com/kalranga/tnadu/4103.htm
Kolam Example #2 Reflection symmetry: horizontal, vertical, and 2 diagonal lines of symmetry
Kolam Example #2 Rotational symmetry at 90, 180, 270. Smallest angle of turn sym shown.
Kolam Example #3 http://www.blueavatar.com/Kolam/Designs/ImageSelector.php
How many lines of symmetry does this design have? A) 0 B) 1 C) 2 D) 3 E) 4 http://www.blueavatar.com/Kolam/Designs/ImageSelector.php
Kolam Example #3 No lines of symmetry, but Rotational symmetry at 90, 180, 270
Kolam Example #4 http://pudukkottai.org/archieve/pongal-2003/images/DSCN0046.jpg
What is the smallest angle of turn symmetry? Assume light and dark blue are to be treated as the “same color tone”. A) 30 B) 45 C) 60 D) 108 E) 120 http://pudukkottai.org/archieve/pongal-2003/images/DSCN0046.jpg
Kolam Example #4 Rotational symmetry at 60, 120, 180, 240, 300 So smallest angle is 60 degrees (blues as same).
Kolam Example #4 Six lines of reflection symmetry: horizontal, vertical, and diagonal line symmetry
Polygon Behind #5 Regular Hexagon The angle of this photo affects the viewing of the regular hexagon. http://pudukkottai.org/archieve/pongal-2003/images/DSCN0046.jpg
Kolam #5 - if dark blue is matched to dark blue, the symmetry changes http://pudukkottai.org/archieve/pongal-2003/images/DSCN0046.jpg
Kolam #5 - if dark blue is matched to dark blue, the symmetry changes Now based on the symmetry of a regular triangle angles of turn symmetry are multiples of 120 degrees http://pudukkottai.org/archieve/pongal-2003/images/DSCN0046.jpg
Kolam #5 - if dark blue is matched to dark blue, the symmetry changes Now smallest angle of turn symmetry is 120 degrees as shown above. http://pudukkottai.org/archieve/pongal-2003/images/DSCN0046.jpg
Kolam #5 - if dark blue is matched to dark blue, the symmetry changes Now 3 lines of reflection symmetry as shown. http://pudukkottai.org/archieve/pongal-2003/images/DSCN0046.jpg
Kolam #5 - if dark blue is matched to dark blue, the symmetry changes Now 3 lines of reflection symmetry as shown inside regular triangle. Going through vertex to midpoint of opposite side. http://pudukkottai.org/archieve/pongal-2003/images/DSCN0046.jpg
Summary/Conclusion • Rotational symmetry seems to exist in about 90% of the designs, while reflection symmetry only in about 25% • Usually the designs are curved lines and no well known math shape is made directly in the design. • Behind the scenes regular polygons with an even number of sides drive the symmetry of the design.
Summary/Conclusion • Two types of images that did appear in several designs were flowers and birds • Due to the use of powdered stone or chalk, usually the design is white in color
References Images and Background Information: http://www.tamilnation.org/images/culture/kolam/kolam5.jpg http://www.kamat.com/kalranga/tnadu/4103.htm http://www.saigan.com/heritage/alangaram/kolams/pko4.html http://pudukkottai.org/archieve/pongal-2003/images/DSCN0046.jpg http://www.blueavatar.com/Kolam/Designs/ImageSelector.php