NXT Rubik's Cube Solver (with videos)

[atbrask]

Hi,

As part of a embedded systems course at the university we (myself and two others) have created a robot that solves Rubik's cubes. In this project we have used leJOS, so we thought it would be interesting to post here.
We use two Hitechnic NXT Color Sensors to scan the cube, which has resulted in an updated lejos.nxt.ColorSensor class. All computations involved in the solving process are carried out in the NXT brick alone. No cheating.

For those who can read Danish, here is our project blog:
http://eseaacj.blogspot.com
(And for the rest of you there are some pretty pictures )

During the process we have made a few youtube videos. The first one demonstrates our initial construction:
http://www.youtube.com/watch?v=qCUooMoYE3U

The second one demonstrates the motor control abstraction layer:
http://www.youtube.com/watch?v=3EUPoTFuw1M

The third one show the final robot scanning and solving a cube all the way.
http://www.youtube.com/watch?v=vTGhH98daLo

We unfortunately don't have building instructions for this. But you can find our source code here:
http://www.daimi.au.dk/~jn/lego/esea-rubikssolver.zip

Regards,
The Rubik's Cube Solver Team

[kirkpthompson]

That is amazing! I can't even begin to comprehend the math..

Great job and project!

-K

[mdsmitty]

Great job.
I am so tired of seeing cube solving robots that are controlled by the computer. I am thrilled to see one that the brick does all the work. I have toyed with the idea to doing something similar but i have been working on my checkerBot and i don't want to tear it apart.
Once again great job A++++

[lawrie]

Thanks for posting the details of this excellent project, and thanks for donating the updated ColorSensor class to the leJOS NXJ project.

That is a lot of leJOS NXJ code!

It show that quite complex applications can be run on the NXT using leJOS NXJ.

[99jonathan]

how long did that final video take in real time?

[atbrask]

That is amazing! I can't even begin to comprehend the math..

Great job and project!

-K

Great job.
I am so tired of seeing cube solving robots that are controlled by the computer. I am thrilled to see one that the brick does all the work. I have toyed with the idea to doing something similar but i have been working on my checkerBot and i don't want to tear it apart.
Once again great job A++++

Thanks guys!

Thanks for posting the details of this excellent project, and thanks for donating the updated ColorSensor class to the leJOS NXJ project.

That is a lot of leJOS NXJ code!

It show that quite complex applications can be run on the NXT using leJOS NXJ.

No problem.

how long did that final video take in real time?

I think it was 24 minutes in this case. The main bottleneck is the number of steps the solution requires, as we chose a relatively simple algorithm to keep the complexity down. But it's not that bad in this video. The first working (unoptimized) version of the algorithm took even longer.

[ranulfgreen]

Hi,

I also built a cube solving robot a couple of years ago using the old RCX! took 45 minutes to solve since the motors where so unpowerful! Full respect goes out to anyone who builds a robot and software from scratch, its a mamouth task, my robot used around 3000 bits and took weeks to construct. Out of interest, which algorithm did you go for, I used a variation of Kociemba's algorithm. My bot's on youtube at:

http://www.youtube.com/watch?v=la2LtrQ8k_I