Pages: [1] 2   Go Down
 Author Topic: Surrealistic Rubik's Cube robot [Auto-solver]  (Read 3995 times) 0 Members and 1 Guest are viewing this topic.
Venezuela
Offline
God Member
Karma: 16
Posts: 512
Ground, ground, always ground
 « on: September 25, 2013, 09:51:53 am » Bigger Smaller Reset

Reading the title of an upcoming article in the August 2013 Circuit Cellar Magazine (Build a Rubik’s Cube-Solving Robot, by Nelson Epp), it reminded me an idea that has been whirling in my mind for some time: A Rubik's cube robot that solves itself. Imagine for a moment a disordered 3x3x3 Rubik's cube that you just place on a surface and after a couple of seconds starts to bounce and flip, rotating its six faces and few seconds later stops with all of them now one-colored. What should be required to build this imagined 'surrealistic' Rubik's cube? I haven't read yet Mr. Epp's article but let's make an exercise imagining what parts should be required. Here my quick-start list:

1- Arduino micro
6- Full rotation servos
6- 3-axis-Gyroscopes (or Accelerometers)
1- Battery
1- Rubik cube.
Plus the Rubik's algorithms (the robot should knows in advance the unscrambled color positions).
What else?

Notice that my idea do raise other questions like what size or how fast will the robot solves itself?
(Current record: 5.27 secs CubeStormer II). Regards!
 « Last Edit: September 26, 2013, 09:34:52 pm by Palliser » Logged

Global Moderator
Netherlands
Offline
Shannon Member
Karma: 212
Posts: 13531
In theory there is no difference between theory and practice, however in practice there are many...
 « Reply #1 on: September 25, 2013, 02:01:38 pm » Bigger Smaller Reset

270 degree servo's should do as RRR == -R  but maybe that "interferes" with the algorithms.

full rotation allows human interaction too

instead of a jumping cube it could stand on one corner (diagonally) on some standard that holds the batteries and the Arduino. That gives more room for the servo's.

And I want definitely LED lights in, and when it is solved it must play the tune of "close encounters" ta da da ta daaaaaaaa...

 Logged

Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

Cape Town South Africa
Offline
Edison Member
Karma: 19
Posts: 1217
A newbie with loads of posts, and still so much to learn !
 « Reply #2 on: September 25, 2013, 02:46:58 pm » Bigger Smaller Reset

I shall follow this thread, I am way too busy to get my head around even the mechanism to rotate the shapes

( normally we grasp the outer rings to turn the various groups of segments.... hmmm  ) .

Good luck guys !
 Logged

With my mobile phone I can call people and talk to them -  how smart can you get ?

Belgium
Online
Edison Member
Karma: 68
Posts: 1903
Arduino rocks; but with my plugin it can fly rocking the world ;-)
 « Reply #3 on: September 25, 2013, 03:31:08 pm » Bigger Smaller Reset

If you want then human rotatable (after all who is going to scramble it?) I would go for steppers.
To know the colours you can use a cam or some kind of markers inside the cube.
Best regards
Jantje
 Logged

Do not PM me a question unless you are prepared to pay for consultancy.
Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -

Cape Town South Africa
Offline
Edison Member
Karma: 19
Posts: 1217
A newbie with loads of posts, and still so much to learn !
 « Reply #4 on: September 25, 2013, 03:51:16 pm » Bigger Smaller Reset

Of course you could have SMD RGB LEDs in each face and do it all software,  but perhaps nobody watching will believe it if they cant see it turning ?
 Logged

With my mobile phone I can call people and talk to them -  how smart can you get ?

Venezuela
Offline
God Member
Karma: 16
Posts: 512
Ground, ground, always ground
 « Reply #5 on: September 26, 2013, 09:21:48 am » Bigger Smaller Reset

robtillaart, I really like your idea of holding diagonally the cube but I'm still thinking in the robot as a stand-alone cube that besides its ability to solve itself, also a human can grab it and scramble it anytime (or even can be used to give the impression that you are solving it!).

Jantje, you idea of using steppers is very good and it will get rid of the gyros but not sure yet.

Boffin1, the RGB LEDs could be an add-in to watch the robot in action in the dark but I see the wiring quite a challenge.

Anyway, here my back of the napkin sketch of the 6 servos. Regards!
 Logged

Phoenix, Arizona USA
Offline
Karma: 39
Posts: 5557
Where's the beer?
 « Reply #6 on: September 26, 2013, 05:56:59 pm » Bigger Smaller Reset

Anyway, here my back of the napkin sketch of the 6 servos. Regards!

Nice sketch - but I think servos are going to limit you due to the shaft offset from the body.

I'd go for something with a centralized shaft (which you'd have to come up with your own feedback system to know position, etc) - something like those small micro-gearmotors might be ideal:

http://www.robotshop.com/productinfo.aspx?pc=RB-Pol-77&lang=en-US

Or - alternatively (but probably hella expensive) would be these "smart" servos:

http://www.robotshop.com/productinfo.aspx?pc=RB-Rbs-120&lang=en-US

...although, looking at their size, they aren't small - your "cube" would be fairly large...
 Logged

I will not respond to Arduino help PM's from random forum users; if you have such a question, start a new topic thread.

Venezuela
Offline
God Member
Karma: 16
Posts: 512
Ground, ground, always ground
 « Reply #7 on: September 26, 2013, 06:13:47 pm » Bigger Smaller Reset

Anyway, here my back of the napkin sketch of the 6 servos. Regards!

Nice sketch - but I think servos are going to limit you due to the shaft offset from the body.

Hello cr0sh,
Thanks for your comments. Regarding the shaft offset, I just have come up with a solution (see picture below) but you are right about the size; this new arrangement increased the size of the cube up to 8.02 x 8.02 inches, but remember, this is a prototype. I will be checking your links. Thanks!

 Logged

Venezuela
Offline
God Member
Karma: 16
Posts: 512
Ground, ground, always ground
 « Reply #8 on: September 26, 2013, 09:37:25 pm » Bigger Smaller Reset

This is pretty much what I am pursuing for (after 0:10).
 Logged

Offline
God Member
Karma: 7
Posts: 647
"In this house, we obey the Laws of Thermodynamics" Homer J. Simpson
 « Reply #9 on: September 27, 2013, 03:32:12 am » Bigger Smaller Reset

I think this is a fantastic idea.
How are you going to get the power and control to the motors though?
 Logged

Venezuela
Offline
God Member
Karma: 16
Posts: 512
Ground, ground, always ground
 « Reply #10 on: September 27, 2013, 06:34:39 am » Bigger Smaller Reset

I think this is a fantastic idea.
How are you going to get the power and control to the motors though?

I don't know yet. I am waiting for the barman with my drink and another pile of napkins. But let's revise some facts here while sitting in the bar. The faster the code solves the cube, the batteries consume less current. I am not a Rubik's cube solver expert but I've read about 52 steps algorithms or so in the web, which means that each servo should rotate about 10 times per effective solving. Then it's about to write some calculations (that's why the napkins) and estimate the capacity of the batteries and finally check if the characterized battery exists. In reference to the code (I am planning to use a Fio given that I can program it been from inside the cube). I don't have the answer yet either but as I said, it should be a very good code (I've also seen 5 minutes cube solver out there!). Let's see how it goes. Regards!
 Logged

Offline
God Member
Karma: 7
Posts: 647
"In this house, we obey the Laws of Thermodynamics" Homer J. Simpson
 « Reply #11 on: September 27, 2013, 10:28:59 am » Bigger Smaller Reset

A Rubik's cube 'appears' to be made of 3x3x3 smaller cubes.
However there is no central cube so that reduces to 26.

Of these cubes there are;
 8 corner cubes 3 faces visible each 24 faces total 12 centre of edge cubes 2 faces visible each 24 faces total 6 central cubes 1 face visible each 6 faces total 26 cubes total 54 faces total

That sounds a lot but of course the cubes are not really free to move at random.
Maybe it would be possible to brute force the cube and calculate in advance the shortest path from any starting point?

 Logged

Cape Town South Africa
Offline
Edison Member
Karma: 19
Posts: 1217
A newbie with loads of posts, and still so much to learn !
 « Reply #12 on: September 27, 2013, 11:25:04 am » Bigger Smaller Reset

this shows an external slice turning method, hard to imagine tiny servos turning all the outer slices ..
 Logged

With my mobile phone I can call people and talk to them -  how smart can you get ?

Venezuela
Offline
God Member
Karma: 16
Posts: 512
Ground, ground, always ground
 « Reply #13 on: September 27, 2013, 12:06:04 pm » Bigger Smaller Reset

A Rubik's cube 'appears' to be made of 3x3x3 smaller cubes.
However there is no central cube so that reduces to 26.

Of these cubes there are;
 8 corner cubes 3 faces visible each 24 faces total 12 centre of edge cubes 2 faces visible each 24 faces total 6 central cubes 1 face visible each 6 faces total 26 cubes total 54 faces total

That sounds a lot but of course the cubes are not really free to move at random.
Maybe it would be possible to brute force the cube and calculate in advance the shortest path from any starting point?

That’s also an interesting video Boffin1. I believe, nowadays, the solving a ‘dumb cube’ from the outside (robots, grips, etc.) gives us enough ideas to start thinking a way to do it from the inside.

My initial thought about solving the cube (as a simple exercise to test the hardware) was to reverse the solving process. I mean, the cube always memorizes the steps from the initial solved position to the final scrambled position (whatever). Then, the cube only needs to 'undo' the steps to go to the original solved position...which reminds me a chapter of the book “Iconostasis” by Pavel Florensky (Russia's unknown da Vinci) where he explains that all that we dream in a dream, and that seems to last a long time, is the result of what happens to us just before waking up. A reversed chain of events that lasts for few microseconds. Regards!
 Logged

Offline
God Member
Karma: 7
Posts: 647
"In this house, we obey the Laws of Thermodynamics" Homer J. Simpson
 « Reply #14 on: September 28, 2013, 01:10:17 pm » Bigger Smaller Reset

Like I said I think this is an excellent idea, but there are enormous practical problems.
Boffin1 is right bout the servos, a fair bit of force is required to move the faces.

Can anybody say how many states a rubik's cube actually has?
In other words how many unique combinations can one be scrambled into.

Also don't you wish you had a real talent and skill like this;

 Logged

 Pages: [1] 2   Go Up