Abstract

Rubik's Cube, a 3-D combination puzzle invented by Ernő Rubik in 1974, is the World’s top-selling puzzle game and best-selling toy. Rubik's Cube is surprisingly complex, there are 43,252,003,274,489,856,000 permutations of a standard 3×3×3 Rubik's Cube. Although humans are impossible to memorize all permutations of a Rubik’s Cube, humans can solve the puzzle as fast as 3.47 seconds. In recent years, a robot developed by MIT students can solve it in 0.38 seconds using an optimal algorithm.

In this project, I developed a Rubik’s Cube-solving robot using a Computer Vision algorithm from scratch. The robot has 4 stepper motors and 4 servo motors as actuators. A camera is included to observe each color arrangement of the face of the Cube in a scrambled state sequentially. The image that the camera observed will be sent through a serial interface to the computer. I implement a solving algorithm that will take the Cube state as input and the sequence of moves that solve the Cube as an output. The sequence of moves is sent to the MCU and is then translated into a series of instructions. The stepper motors and the servo motors then work together to twist the Cube according to the instructions, fully solving the Cube.