A solution for Rubik's UFO
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(click on the image above to enlarge)
The Rubik's UFO is another remarkable puzzle that I had the pleasure to play
with.
Its close relation to Rubik's Cheese (one of the rarest puzzles) makes it
more interesting!
It is a puzzle which allows you to actually spin(!) it, while trying to find a way to solve it...
If you are a beginner, try and use only flips, not twists...!
By using flips, the total combinations are 96. However, if you
combine the flips together with the twist, the combinations explode
to (almost) FOURTY MILLION!!!! :-P
________ THE SOLUTION ________
The Rubik's UFO is a two layer puzzle and it has three generators of order two (flips), and one of order six (twist)
The solved state (zero position) looks like below. The left part is assumed
to be the front face,
while the right part is assumed to be the back face. For convenience, both
sides are shown at the same time.
To be as clear as possible, I will describe the flips, twist, and other moves,
by having the zero position as the starting point.
All the generators (the three flips A, B, C and the twist T) are described
below.
The flip A, or simply A, is
defined as the vertical flip of the right side
The flip B, or simply B, is defined
as the down-right diagonal flip.
The flip C, or simply C, is defined
as the up-right diagonal flip.
The twist T, or simply T, is
defined as the clockwise rotation of the FRONT face by one tile position.
By -T, we define an anticlockwise
rotation of the front face by one tile position.
The Two Main Moves, M1 and M2:
The only two moves you will need to know for solving the puzzle are now presented.
(in half of the cases, you may only need to remember the first one!)
The Move M1, swaps the two pieces on the top-front of the front face.
It does exactly the same thing with the top-front pieces of the back face
The Move M2, swaps ONLY the two pieces on the down-right of the front face.
It doesn't change any of the pieces of the back face.
The moves M1 and M2 (described below in term of the three flips and the twist) are enough to solve the puzzle.
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M1:
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A
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T
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A
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-T
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-T
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C
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T
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A
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M2:
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(
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A
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T
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A
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B
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T
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T
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A
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B
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T
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)
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x
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5
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HOW TO USE M1 AND M2
Assume you have ended up with a scrambled Rubik's UFO. DON'T PANIC!
(Spinning the puzzle can enormously reduce the stress and bring a relaxing
aura).
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1.
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Make sure that one side contains only
dark grey tiles, and the other side contains only light grey tiles (come
on, it's not that hard to do this!)
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2.
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By using M1 swap adjacent tiles, until
NONE or ONE are unsolved.
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3.
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In the unfortunate event where a single
pair of tiles is still unsloved, use M2. That is, repeat the sequence
[AT ABTT ABT] five times!
(if anyone has a simpler sequence than this, please let me know LOL) |
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You may notice by applying the sequences many times, that they are both easy to remember.
Like mentioned, those moves are enough to solve the puzzle, but in addition
to them I have a few more things to points out:
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1.
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The move M2, is either not used at all, or it is used as
a very last move. |
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2.
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Don't be afraid to use the twist BEFORE using
M1. You may need to use the twist to choose the appropriate pairs that
you want to swap. |
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3.
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When using M2, try to not mix yourself up LOL. But even if you do, chances are than by applying M1 to the re-scrambled puzzle, you will solve it without the having to apply M2 in the end. |
It is estimated that to completely solve the puzzle, you probably need to
use M1 four times (and maybe M2 once).
All the tips, as well as all using M1 and M2, require practice, practice and
more practice! ;-)
(well.... not much practice really...)
Myself, I never use the move M2, and the only reason
I present it here is to make the solution easier for beginers.
You may actually solve the puzzle by only
using the move M1 in the correct order
to avoid parity problems...! ;-)
(don't ask me to define this, you should be able to find out sooner or later!)
Finally, here is a picture of a Rubik's UFO, spotted somewhere near my island
in Greece! :-P
Please let me know of any comments or suggestions. Thanks! :-)