Android Phone Solves Rubik's Cube In 12.5 Seconds

DeviceGuru writes "A Lego Mindstorms robotics kit controlled by an HTC Nexus One smartphone successfully untangled a Rubik's Cube puzzle in 12.5 seconds at this weeks ARM technical conference in Silicon Valley. The current 3x3x3 cube-solvers's 15-second average represents a substantial improvement over the 25-second solutions of an earlier version, which was powered by a circa-2006 Nokia N95 smartphone, thanks to a faster (1GHz) CPU, more RAM, and revamped cube-solving algorithms. ARM Engineer David Gilday, who created the robotic cube-solver, claims the current version's algorithms can handle cube complexities up to 100x100x100, assuming he build the mechanics. In terms of racing humans, Gilday says the Lego robotics kits can only manage around 1.5 moves per second, whereas human players can make between 5 and 6 moves per second, amazingly enough." Update: 11/12 03:45 GMT by T : Apologies to creator David Gilday, whose name was earlier misspelled.

Re:so...

[MichaelKristopeit161]

the problem is the qualifier "CAN make"... the precondition being only certain subsets of 5 and 6 moves can be made in 1 second. the moves necessary to solve the cube will not always fall within those subsets.

i can solve any cube in under 3 minutes and that's fast enough for me.

Ah yes...

[Oxford_Comma_Lover]

> thanks to a faster (1GHz) CPU, more RAM, and revamped cube-solving algorithms.

I love how a few hundred million math operations per second is no longer enough for our phones, while most information in the human voice is under 8Mhz, IIRC.

It feels a little like the math we teach our children is teaching them how to play with rocks in a cave. But they will never, ever, do what the computer is able to do already.

Though they will do other cool stuff.

Re:Does it matter it was done with ARM?

[fuzzyfuzzyfungus]

I'd be curious to know exactly how limited the hardware could be while still implementing the cube solving algorithm. Clock speeds are just a matter of patience, half the speed just means waiting twice as long; but there has to be an amount of RAM below which the algorithm Just Can't Be Done.

As for the hardware side, I imagine that the guys who do really serious high speed CNC machinery could probably achieve better-than-human speeds, though the device would probably cost 100k and require the cube to be continuously sprayed with a coolant/lubricant fluid to avoid thermal or mechanical damage...

Another interesting(and potentially cheaper; but with an exciting element of danger!) possibility would be if you allowed yourself to glue a suitably powerful magnet to each surface subcube of the cube, so you could then manipulate it without physical contact, other than one support point, by surrounding it with an array of electromagnets...