A Rubik's Snake (also Rubik's Twist, Rubik's Transformable Snake, Rubik’s Snake Puzzle) is a toy with twenty-four wedges identically shaped liked prisms[1], specifically right isosceles triangular prisms. The wedges are connected, by spring bolts[1], such that they can be twisted, but not separated. Through this twisting, the Rubik's Snake can attain positions including a straight line, a ball (technically a nonuniform concave rhombicuboctahedron), a dog, a duck, a rectangle, a snake and many more imaginative shapes and figures.
The snake was invented by Professor Ernő Rubik, better known as the inventor of the Rubik's Cube.[1]
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Structure
The 24 prisms are aligned in row with an alternating orientation (normal and upside down). Each prism can adopt 4 different positions each with an offset of 90°. Usually the prisms have an alternating color.
Notation
Twisting instructions
The description of an arbitrary shape or figure is based on a set of instructions of twisting the prisms. The starting point is a straight line, where the 12 prisms at the bottom are numbered from 1 to 12. The left and the right turning area of these prisms are labeled which L and R respectively. The four possible positions of the each turning area numbered with 0, 1, 2 and 3 (twist between the bottom prism and its neighbor). The numbering is based on the first clockwise turn of a prism. The position 0 is the starting position and therefore isn’t explicitly noted. A twist is described as:
- Number of the prism: 1 to 12
- Left or right side of the prism: L or R
- Position of the twist: 1, 2 or 3
Before twisting make sure your snake is in a position where the last triangle to the left is facing down so there is a slope.
- for example Three Peaks
- 6R1-6L3-5R2-5L3-4R2-4L1-1R1-3L3-3R2-7L2-7R3-8L1-8R2-9L1-9R2-10L3-12R3-11L1-10R2
- for example Cat
- 9R2-9L2-8L2-7R2-6R2-6L2-5L3-4L2-3R2-2R2-2L2
Machine processing
The position of the 23 turning areas can also be written directly after each other. Here the position 0, 1, 2 and 3 are always based on the degree of twist between the right-hand prisms relative to the left-hand prism, if you look at the axis of rotation from the right. But this notation is impractical for manual twisting, because you don’t know in which order the twists occur.
- for example Three Peaks
- 10012321211233232123003
- for example Cat
- 02202201022022022000000
Fiore method
Rather than numbers Albert Fiore uses letters to refer to the direction the second (rightward) section is turned in relation to the first (leftward) section: D, L, U, and R.[2] These are listed consecutively rather than numbered, so that a completely straight figure rather than being presumed as a starting point is notated DDDDDDDDDDDDDDDDDDDDDDD.[3]
Mathematics
The number of different shapes of the Rubik's Snake is at most 423 = 70368744177664 ≈ 7 • 1013, i.e. 23 turning areas with 4 positions each. The real number of different shapes is lower and still unknown, since some configurations are spatially impossible (because they would require multiple prisms to occupy the same region of space).
See also
Sources
External links
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Wikimedia Commons has media related to: Rubik's Snake |
- Official Rubik's Online Site
- Collection of shapes and figures of Rubik's Snake
- glsnake - open-source cross-platform implementation of Rubik's Snake (also ported to XScreenSaver)
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