harlan chernoff technical definition and description final draft
TRANSCRIPT
Harlan Chernoff
The Rubik’s Cube
English 202C
October 23, 2012
Figure 1: Rubik's Cube
Figure 2: The first working prototype of the
Rubik’s Cube
Audience and Purpose
The purpose of this technical document is to inform its audience about a Rubik’s Cube. The
document will focus specifically on the original three-by-three Rubik’s Cube. (There are Rubik's
Cubes with other sizes, such as the four-by-four “Rubik’s Revenge Cube” and the five-by-five
“Rubik’s Professor’s Cube.”) After reading this document, the audience will know the history of
the Rubik’s Cube, will be able to visualize the parts of the Rubik’s Cube, and will understand
how the Rubik’s Cube works. The document is intended for an audience that includes people
who are interested in puzzles and who have a basic understanding of high-school geometry.
The document could appear in a magazine, on an educational website, or even in a book about
famous puzzles or toys.
Introduction
A Rubik’s Cube is a three-dimensional puzzle cube.
Each of the six faces of the cube is divided into nine
separated sections in a three-by-three grid. These
sections are colored, typically with stickers, and each
of the faces of the cube is a different color. The
traditionally used colors are white, yellow, red,
orange, green, and blue. A swivel mechanism enables
each section of the cube to rotate and thus mix up
the colors on the different faces. As shown in Figure
1, the puzzle is “solved” when all nine sections on
each face are the same color.
Background and History of the Rubik’s Cube
The inventor of the Rubik’s Cube, Ernö Rubik, was born in
Budapest, Hungary, in 1944. Rubik invented the Rubik’s
Cube (Figure 2) in 1974 when he was a professor of
architecture at the Academy of Applied Arts and Design in
Budapest. When he invented the Rubik's Cube, he did not
have the intention creating a puzzle. His main purpose
was academic, that is, to investigate the structural
concept of independently moving parts in a mechanism
3
21
Figure 4 (left) shows all of the
components of the Rubik’s Cube.
1. Twelve side-edge pieces
2. Eight corner pieces
3. Core three-dimensional cross
piece on which the centers of
the faces rotate
Figure 4: The twenty one pieces of a Rubik's Cube
that stayed fully intact. He himself did not realize the
potential of the Cube being a puzzle until he had
difficulty storing his model to its original status after he
had scrambled the arrangement by moving the parts.
The Cube was patented in Hungary 1975 as the “Magic
Cube,” and it was sold successfully in Hungary. In 1980,
the Magic Cube was renamed to the Rubik’s Cube, and it
was sold internationally to become one of the most
successful toys ever produced. More than 350 million
Rubik's Cubes have been sold. Figure 3 shows the Rubik’s
Cube and its packaging as it was first sold in the United
States.
The popularity of the Rubik's Cube is partially derived from its reputation for difficulty. The
Cube presents a nearly impossible challenge to people who attempt to solve it with random
movements. The ability to solve a Rubik's Cube became a symbol of intelligence that borders
on genius. Recently, in the 2006 movie, The Pursuit of Happyness starring Will Smith, the main
character gains access to a prospective employer by solving the Rubik’s Cube.
Specifications and Functionality
Although the concept of the Rubik’s Cube may seem very simple, the design of the Cube is
actually quite complex. The original three-by-three design of the Rubik’s Cube features six
central pieces (with one exposed face), eight corners (with three exposed faces) and twelve
side-edge pieces (with two exposed faces).
Figure 3: Packaging of the Rubik's Cube (1980)
Figure 6: Assembling the pieces of a
Rubik's Cube
There are eight-factorial ways to arrange the corners and three ways to orient each corner.
There are twelve-factorial ways to arrange the side pieces. The number of possible
arrangements the Rubik's Cube is in the quintillions: 43,252,003,274,489,856,000. Another
way of describing these possibilities is there is only one correct or solved arrangement, and
there are 43,252,003,274,489,855,999 incorrect arrangements. Because of the scale of these
numbers, random solutions are virtually nonexistent, and a person who is able to deduce
helpful algorithms to solve the Cube acquires the mystique of genius.
Figure 5 (left) shows that the Rubik’s Cube has
dimensions of 5.7 centimeters on each side. The
Rubik’s Cube consists of a total of twenty-one parts.
There are eight corner pieces, twelve side-edge
pieces, and the core swivel mechanism. The core
swivel mechanism is the most complex piece. Most
of the materials used in the production of the
Rubik’s Cube are thermoplastics. The typical
production of a Rubik’s Cube is a step-by-step
process that involves injection molding of the
individual pieces, assembly of all the pieces, and
labeling the faces with their respective colors (Figure
6, below).
Conclusion
The surface of the Rubik's Cube has the form or surface
appearance of a cube, but the actual components used to
assemble the Rubik's Cube reveal a very sophisticated
conception. In function as well, the apparent simplicity of
the task of solving the puzzle contrasts with the extremely
large number of permutations of the possible
arrangements. This combination if simplicity and
complexity is part of the appeal of the Rubik's Cube.
5.7cm
5.7cm
5.7cm
Figure 5: Dimensions of the Rubik's Cube
References
http://web.mit.edu/sp.268/www/rubik.pdf
http://www.rubiks.com/world/history.php
http://www.puzzlesolver.com/puzzle.php?id=29;page=15
http://www.flickr.com/photos/soheilk/4438771159/
http://en.wikipedia.org/wiki/File:1980-Rubik%27s-Cube.jpg
http://www.madehow.com/Volume-7/Rubik-s-Cube.html
http://math.williams.edu/rubiks-cube-turns-30/
http://www.math.cornell.edu/~mec/Winter2009/Lipa/Puzzles/lesson2.html