X

Lego robot controlled by Nexus One solves Rubik's cube in 12 seconds

With just an Android application and a pile of spare Lego, an engineer has managed to make a robot that can solve a Rubik's cube in double-quick time.

Asavin Wattanajantra
2 min read

ARM engineer David Gilday has combined the Google Nexus One, some Lego and a Rubik's cube, in a tech demo that can only be described as the geek Holy Grail. We bow before him.

Gilday's Lego Mindstorm robotics kit untangled a Rubik's cube puzzle in 12.5 seconds using HTC Android software, deviceguru.com reported from the US ARM tech conference. This was a significant improvement on an earlier robot controlled with the Nokia N95, which took 25 seconds to solve the iconic puzzle.

Lego Mindstorms allows you to build robots with Lego and program them to do your bidding. PC software sends messages via a controller to intelligent bricks carrying tiny micro-computers, in turn activating motors and sensors.

"It's a robot that I made out of Lego, a children's toy," Gilday said. "It uses an Android mobile phone application that can communicate with the standard Lego Mindstorms controllers."

The Rubik's cube is plopped inside the robot, with the Nexus One on top. From here the smart phone can use its camera to take pictures of the cube. The application on the Nexus One instructs the controller to turn the cube over so it can analyse the colours.

"Once it takes a picture of all the sides it can work out the solution and send it to the controller," the engineer said. "It solves the Rubik's cube for you."

But it's not just Rubik's classic 3x3x3 cubes that Gilday tried to solve. Using a different software algorithm and a spot of technical japery, he managed to power a Lego Mindstorms robot to solve a 7x7x7 puzzle with a Motorola Droid (known as the Milestone in the UK).

It took far longer -- some 500 moves and about 40 minutes -- to solve the puzzle. We're trying not to think how long it would take us.