Motor suggestions for rubiks cube scrambler

[cgmv123]

Originally Posted by EricH

Already been done, in LEGO

Already been done, and then some: http://www.youtube.com/watch?v=X0pFZG7j5cE

[faust1706]

As for programming, here is how I would do it:

j = random number between n and m (I'd do 25 and 50)

for (unsigned int i = 0; i < j;i++)
generate a random number 1 to your total number of motors

then turn that motor either 90 or 180 degrees.

[phantomoperator]

I like the stepper motor idea. For our design we would need to control 5 motors. Our designs involves having little fixed jaws that fit around the center piece of the cube. We concluded that in order to fully scramble the cube we must turn 5 of the six faces.

Does any one have suggestions on a controller board?

[techhelpbb]

Originally Posted by phantomoperator

I like the stepper motor idea. For our design we would need to control 5 motors. Our designs involves having little fixed jaws that fit around the center piece of the cube. We concluded that in order to fully scramble the cube we must turn 5 of the six faces.

Does any one have suggestions on a controller board?

How about a RAMPS 1.4 like they use for RepRap 3D printers.
That will handle 5.5 steppers...one is a split signal.

[phantomoperator]

That would work. Would I be able to control all of the motors independently?

[techhelpbb]

Originally Posted by phantomoperator

That would work. Would I be able to control all of the motors independently?

You have 5 independent drivers so yes.
If you watch any RepRap run you can see steppers moving at the same time independently.

The 0.5 stepper is usually used on dual Z printers like the Prusa.
You put 2 steppers on one driver each at half power but they move at the same time anyway and move the same axis in unison so that is fine. Still the others are independent in that setup.

[phantomoperator]

Awesome. That will work perfectly. Now my last question is how will we go about telling the motors what to do. Whaat we were hoping to do was have this be completely independent of a computer. We wanted to have a button that we could press and it would automatically generate a random scramble and mix up the cube.

[techhelpbb]

Originally Posted by phantomoperator

Awesome. That will work perfectly. Now my last question is how will we go about telling the motors what to do. Whaat we were hoping to do was have this be completely independent of a computer. We wanted to have a button that we could press and it would automatically generate a random scramble and mix up the cube.

Populate RAMPS shield with stepper drivers (Pololu).
Attach Arduino Mega to RAMPS shield.
If you need data storage use SD card shield (maybe boot load from it).
If you want an interface attach an LCD or touch screen shield.

These are all parts often used to build RepRap printers.
When used as a printer you can tether the printer with USB (emulated serial) or use a SD card to standalone.
The Arduino provides the USB connection and the SD card shield is obviously for the SD card.
Program the Arduino yourself instead of using a G/M code interpreter that would usually read the G/M code from the card when this is used to be a RepRap printer control.

The platform is still Arduino underneath.

http://www.makergeeks.com/a4stmodrmo.html
http://reprap.org/wiki/Arduino_Mega_Pololu_Shield
http://reprap.org/wiki/RAMPS_1.4 - Test code at the bottom.

Please be aware that the test code uses the Arduino digitalwrite function which is fast enough but there are faster ways to toggle Arduino pins.

[gblake]

In an attempt to help you navigate the thicket of material you will probably find written about this, and similar subjects, I'd like to point out something.

I think I'm correct when I say that "servo" is a *use* for a motor, not a type of motor.

All sorts of motors (including stepper motors) can be used to implement a servo function.

If you keep this distinction in mind, it will probably save you a lot of grief as you wade through what has been written by folks who didn't know about the proper use of the term "servo" (and who enthusiastically mix apples with oranges when giving advice (they are trying to be helpful, but ...)).

Blake