No need to peel off the stickers

September 24, 2018 6:03 AM

Self-solving Rubik's Cube
posted by ook (29 comments total)

Very interesting... but doesnt that take away all the fun? As "fun" as the pure frustration of solving one of those can be, that is.
posted by Black_cat at 6:24 AM on September 24, 2018

This fella is a great analogy for how we should live our lives. All the pieces of the puzzle are there and we are perfect just the way we are. I hear ya, little friend, I hear ya 😭 😭 😭
posted by Foci for Analysis at 6:29 AM on September 24, 2018 [1 favorite]

Peeling off the stickers is a sucker's game.

Just pop off one of the sub-cubes with a flat-head screwdriver and the others will come right off the central mechanism. Then you can reassemble them into a solved cube.

Or so I am told.
posted by Mr. Bad Example at 6:33 AM on September 24, 2018 [10 favorites]

So it 'just' memorizes all the moves and plays them backwards, right?
posted by fearfulsymmetry at 6:35 AM on September 24, 2018 [2 favorites]

Yeah, everyone always claims they remove the stickers but I don't think you could actually peel the stickers off
without destroying them. As a kid we would always just take it apart and put it back together, which is pretty easy to do.

If you really want to mess someone up, remove one of the side pieces, turn it over (so the colors are reversed from how they were) and put it back in. It will no longer be solvable, though it will be obvious to anyone who can solve it that it's been tampered with.

Learning to solve it is actually not that difficult. There are web sites that teach you and I think new cubes even come with the solution. It took me a couple of days to learn but once you learn you can solve any standard cube, no matter how mixed up it is.

You can also build a solver out of Lego Mindstorms. Instructions are out there. My son built one a while back and watching it solve the cube was like magic.

This thing though... this is amazing. I love how it turns itself, almost like it's alive. I hope they start selling them.
posted by bondcliff at 6:39 AM on September 24, 2018 [3 favorites]

(I've taken to using stickerless cubes just to forestall people using that joke on me... Never was able to solve a cube when I was a kid but in these days of youtube tutorials it's really pretty easy, you just follow the recipe...)

fearfulsymmetry, it's not just rewinding -- the code screenshot includes real solve algorithms (F2L in the comments stands for "first two layers," it's a set of rules for solving the top two layers of the cube simultaneously).
posted by ook at 6:41 AM on September 24, 2018

(Which I will never bother to memorize; one layer at a time is much simpler, and not that much slower.)
posted by ook at 6:46 AM on September 24, 2018

fearfulsymmetry, it's not just rewinding -- the code screenshot includes real solve algorithms (F2L in the comments stands for "first two layers," it's a set of rules for solving the top two layers of the cube simultaneously).

Thanks, yeah... I did wonder if the code was solving it, and it did seem to solving the first two layers first in the videos but going backwards seemed the most obvious (and before the move results got too random that's what it seemed to be doing from what I could tell)

Be interesting to know how it does it coz from what I remember the cube solving methods* kinda relied on you being able to see the cube and the last time I saw a robot solving one (by gripping and turning) it had a camera

*a few months back I listened to a nostalgia podcast on how 'You too could can do the Cube!' books were absolutely massive for a time in the UK, but now forgotten.
posted by fearfulsymmetry at 6:48 AM on September 24, 2018

Thanks, I just sent this to my nine-year-old, who's been obsessed with cubing for the past couple of months; he can solve a 3x3 in ~40 seconds, but he has a whole collection from 2x2 up to 5x5, plus skewb and pyraminx. It's funny how things go around.

When he first got into it, I pulled out my old 1980s cube, and we compared them. Boy do the new cubes turn easier. He's nearly 50% slower on my cube.
posted by fings at 7:20 AM on September 24, 2018

*watches video* Gah! Witchcraft!
*looks at CAD renders* ACTUAL WITCHCRAFT
posted by phooky at 7:33 AM on September 24, 2018 [9 favorites]

Be interesting to know how it does it coz from what I remember the cube solving methods* kinda relied on you being able to see the cube and the last time I saw a robot solving one (by gripping and turning) it had a camera

I'd venture that the folks saying it just reverses the moves done to mix up the cube have one thing right: it's designed to register which moves have been manually performed, not so that it can reverse them exactly, but so that it can maintain an internal model of the cube's current state.
posted by jackbishop at 7:46 AM on September 24, 2018 [2 favorites]

> ook:
"(Which I will never bother to memorize; one layer at a time is much simpler, and not that much slower.)"

I dunno, learning F2L changes solving from drudgery to magic.
posted by chavenet at 8:03 AM on September 24, 2018 [1 favorite]

This definitely fits in my category of Adorable Robots. I am reacting to this the way most humans react to a puppy acting very cute.
posted by NMcCoy at 8:06 AM on September 24, 2018 [1 favorite]

*a few months back I listened to a nostalgia podcast on how 'You too could can do the Cube!' books were absolutely massive for a time in the UK, but now forgotten.

Yeah, I recall a time when local bookshops would often have two or three shelves filled with a dozen or fifteen titles on the subject. Of course, I recall a time when there were local bookshops, so...
posted by ricochet biscuit at 8:17 AM on September 24, 2018

Goes to show that people haven't become completely useless. The cube is rescued from proceeding* off the table, and it doesn't square itself up neatly.

*Is there a better word for how it locomotes?
posted by Nancy Lebovitz at 9:27 AM on September 24, 2018

I still have to scramble it myself? Pass.
posted by howling fantods at 10:06 AM on September 24, 2018

So it 'just' memorizes all the moves and plays them backwards, right?

No; I haven't re-watched the first video, but in the one where it's held with fingers during the solving there were about 11 twists to mix it up and something like 50 during solving.
posted by achrise at 10:40 AM on September 24, 2018

God, that cube is adorable. And its handler gently placing it back on the table!
posted by Berreggnog at 11:04 AM on September 24, 2018

I extremely want one.
posted by rifflesby at 11:16 AM on September 24, 2018 [1 favorite]

Very interesting... but doesnt that take away all the fun?

Nah it only takes away 43 quintillion permutations of fun. All the others are still left.
posted by srboisvert at 11:20 AM on September 24, 2018 [1 favorite]

Skynet traveled back in time to get John Connor and got distracted.
posted by srboisvert at 11:25 AM on September 24, 2018 [3 favorites]

Do take note: this here right now, is the start of the robot revolution. This will be the quiet historical moment where they officially take over.

(and not actually totally joking, the compact sensors, battery and motors are clearly very functional and clearly not in the $hundreds per motor, the holdup at this point has been cost and availability of sensors and battery chemistry not hitting a marginal cost. the great great grandson of this cube will be your landlord)

And still it's so cute!
posted by sammyo at 11:27 AM on September 24, 2018 [1 favorite]

The real fun would be to give this to someone and set the cube to solve itself overnight when nobody is looking.
posted by JoeZydeco at 1:13 PM on September 24, 2018 [3 favorites]

If the Rubik's Cube robots took over the world and set everything right, I might just hail them.
posted by M-x shell at 6:11 PM on September 24, 2018

More fulfilling than passing butter, I suppose.
posted by Insert Clever Name Here at 7:23 PM on September 24, 2018 [1 favorite]

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posted by rokusan at 9:26 PM on September 24, 2018

I'd venture that the folks saying it just reverses the moves done to mix up the cube have one thing right: it's designed to register which moves have been manually performed, not so that it can reverse them exactly, but so that it can maintain an internal model of the cube's current state.

I'm going to guess it's designed to generate a series of state maps in between transforms, alternating between the two modes. Each piece knows what it is & what its neighbors are. Put all that together & you know the state of the cube. Apply the master algorithm, determine the next transform to apply then switch to moving mode. When it's done that transform, poll all the pieces, use that to build another snapshot & figure out the next transform.
posted by scalefree at 12:31 AM on September 25, 2018

The real fun would be to give this to someone and set the cube to solve itself overnight when nobody is looking.

Cellphone app to control it remotely. Various modes including direct control, auto-solve, scramble, change parameters like speed & solve for pre-programmed patterns (checkerboard, dot in center, etc). Plus programmable mode to design your own solutions.
posted by scalefree at 12:39 AM on September 25, 2018

Then, in a movie, the cube remote controlled to make it crawl acrossed a desk and press some keys on a keyboard, unlocking building security.
posted by fings at 6:01 AM on September 25, 2018 [1 favorite]