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About this Article
Written by: Charles Cao
Written on: March 16th, 2002
Tags: entertainment, computer science
Thumbnail by: Kleiner/Wikimedia Commons
About the Author
In Fall 2002, Charles Cao was a sophomore in the Class of 2004 and was majoring in Computer Engineering and Computer Science and minoring in Multimedia at the University of Southern California.
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Volume III Issue II > A Simple Complexity
Created as a teaching toy twenty years ago, Erno Rubik's cube quickly became a popular toy that entertained, challenged, and confounded millions of people. The cube consists of a core and attached outer cubes designed to allow rotation on three axes. Rubik's cube can be used to study permutations and algorithms, as well as serving as a test for artificial intelligence systems to learn and develop their own algorithm. Three distinct types of movements can help players solve the cube.

Introduction

Kleiner/Wikimedia Commons
Figure 1: The modern Rubik's cube.
There exists a simple toy that captures the interest of countless people, regardless of age, gender, or education, a toy that requires no batteries or electricity and costs only a few dollars to produce. What type of toy could possibly encompass all of these elements? The answer is deceptively simple: a cube.
Erno Rubik's cube has sparked curiosity around the world for nearly a generation (Fig. 1). Individuals of all ages have spent weeks trying to solve the puzzles. Those who succeed often spend even more time trying to create new patterns in the colors of the cube. Professors have written entire papers totally dedicated to the mathematics behind the cube.
So, what exactly is the cube? Rubik's cube is an engineering marvel that demonstrates mathematic and computer science concepts. This paper will discuss the origin of the cube, the engineering principles at work in the cube, and simple techniques that can ultimately solve Rubik's puzzling toy.

History of Rubik's Cube

Erno Rubik is a native Hungarian born to a poet and an aircraft engineer [1]. In college, Rubik studied sculpture and later went to study architecture at the Academy of Applied Arts and Crafts in Budapest. After graduating, Rubik stayed at the Academy to teach interior design . As a teacher, Rubik developed a habit of creating models to demonstrate his designs to students [1].
Rubik's cube was conceived as a teaching tool, not a toy. He wanted to demonstrate structural design by creating a three dimensional object that could rotate on all three axes. Furthermore, he wanted the object to stay intact as it rotated [2]. Rubik originally experimented with a 2x2x2 cube to figure out how to make such a mechanism. To keep the pieces together, Rubik tried several techniques: elastic rubbers, magnets, and a system of grooves. Unfortunately, all these methods failed . He then came up with the idea of using the shapes of the individual pieces to hold the object together. This led to a success; Rubik created his rotatable cube.
Rubik marked the sides with adhesive paper and tested the cube by rotating several sides. He became captivated by how beautifully the colors mixed, apparently at random. However, when finished testing the cube, Rubik noticed he could not figure his way back to the original configuration. Rubik found that randomly rotating the cube would never bring back the original design. He decided that the only way to solve this cube was to make calculated moves, each with a specified purpose. After a month of experimenting, Rubik solved the cube. He then demonstrated the cube to his students, with whom the cube became extremely popular. The legacy of Rubik's cube spread from this small group of students to the 1979 Nuremberg Toy Fair and eventually to the entire world.