The beauty of the Lego NXT system is that it can create just about anything that your imagination desires, even if you want to make a robot that automatic solves the Rubik’s Cube puzzle for you.
There are several components to this gadget, including a motor that actuates a prismatic joint, which in turn pushes the side of the cube. You’ll also find another to rotate the cube’s support, and a third to help the pusher arm to accomodate the cube (and to hold it while the bottom is rotated). The “light sensor” is a basic webcam. And finally, the last component appears to be a notebook computer running a homebrewed program.
Now, you’ve got to wonder: if you can put together such a complex robot, why can’t you solve the stupid Rubik’s Cube yourself?