Search within Lanny's blog:


Leave me comments so I know people are actually reading my blogs! Thanks!

Tuesday, February 10, 2009

Robot of the Day: CubeStormer, the Rubik's Cube Solver

Ever played Rubik's Cube before? If you have, then you know how hard and how long it takes to solve a game of Rubik's Cube. The robot we talk about today, however, can solve it within seconds, and most impressively, the robot was built completely using Lego pieces from the Lego Mindstorms Kit, which means you could build a robot just like this yourself for only a couple hundred bucks!

The robot's name is CubeStormer, built by British engineer Mike Dobson using Lego Mindstorms parts hooked up to a laptop computer. The computer acts as the brain and performs tasks such as recognizing colors, solving the puzzle using algorithms, and sending motor commands.

As shown in the video below, the robot first quickly inspects all six sides of the cube using multiple cameras by first rotating it a few times to recognize the current state of the cube. The computer vision task is actually really simple because the cube is placed at a fixed position, so the recognition software only needs to sample a few points for each color piece and then simply detect the color of the pixels (one out of six possible choices). The state of the cube is then passed on to a solver software (such as this free online one) and sequences of moves are generated, which are translated into motor commands for the robot to perform.

What is impressive about this robot, though, is the engineering side of things, such as how parts are connected and how motors are used all with toy Lego pieces. A beautiful designed enabled the robot actuators to solve the game in such short period of time. If you look closely at the video, you'll also notice that two rows of the cube can be rotated at the same time to speed it up!

CubeStormer by Mike Dobson

The time it took the robot to solve a random game was about 12 seconds. This is very much comparable to the fastest human Rubik's Cube solvers such as the one shown below.

Rubik's cube official world record 7.08 Erik Akkersdijk

There are of course other Rubik's Cube solving robots in the wild, such as the one built by UC Berkeley shown in the video below, which solved a puzzle in 6 seconds. But apparently this robot would cost a lot more.

Rubik's cube solver by UC Berkeley

However, the Cubinator, aka RuBot II, by Pete Redmond from Dublin, Ireland gets extra point in my book of Human-Robot Interaction. Although much slower compared to the other two robots, it has a head and two arms. And after picking up the cube all by itself, it even played music and talked to the audience while solving the puzzle.

Cubinator by Pete Redmond

What if the Cubinator not only solves Rubik's Cube, but is also capable of playing board games or hide-and-seek with your kids, tell them jokes, read books for them, and help them with their homework? Would you want one for your kids? If so, for how much? If not, why?

Picture of the Day:

Leftover Valentine’s chocolate? Use it to measure the speed of light with your microwave. Click the picture to find out how!