Build your own LEGO® MINDSTORMS® robot to solve the Rubik's Cube®...
MindCub3r is a robot that can be built from a single LEGO MINDSTORMS EV3 kit (item 31313, home edition) that can solve the well known Rubik's Cube puzzle.
Note: this release works with the standard LEGO MINDSTORMS EV3 firmware version 1.06H (the original release including the enhanced firmware, v1.05M, is still available here)
Construct the robot by carefully following the build instructions and then download and install the software described below.
MindCub3r software consists of three main parts:
Note: release v1p1 uses the .rtf extension to enable the files to be downloaded using the standard LEGO MINDSTORMS EV3 software. The .rtf extension is intended to be used for files containing text so using if for the executable program is a work-around. Please do not try to open this file with a text editor.
MindCub3r uses the EV3 color sensor in RGB mode to enable it to measure colors that cannot be distingished by the standard color mode provided by the standard LEGO MINDSTORMS EV3 software. The Color Sensor RGB Block must be imported into the LEGO MINDSTORMS EV3 software to support this mode.
MindCub3r is now ready to use!
Run the "MC3 Solver v1p1" application on the EV3 from the
Brick Apps screen to start the mc3solver-v1p1.rtf
This is only necessary once each time the EV3 is turned on as the program will continue to run in the background until the EV3 is turned off.
Run the MindCub3r program on the EV3 from the
Run Recent screen or from the File Navigation
screen if it is the first time it has been run.
The program first resets the position of the scan arm (holding the color sensor) and then the tilt arm. If the turntable starts to rotate or the two arms do not move in this order, please carefully check that cables have been connected to the correct ports on the EV3 as shown by the color coding in the build instructions. During this period, the EV3 buttons flashes red.
The program then connects to the mc3solver-v1p1.rtf program that was downloaded to the EV3. If the program is found, the EV3 makes a short beep and continues. If the solver program is not running, the buttons continues to flash red and the message "Find solver" is displayed on the EV3 screen. If this happens, please check that the "mc3solver-v1p1.rtf" program has been downloaded to the MindCub3r-v1p1 project folder on the EV3 and that the "MC3 Solver v1p1" application has been installed and run once.
When MindCub3r is ready to start, the EV3 buttons turn orange and the message "Insert cube..." is displayed on the screen.
Gently turn the turntable in each direction with your finger so that it moves slightly because of "play" in the gears connecting it to the motor. If necessary, adjust the position of the motor so that there is an equal mount of play in each direction. Use the left and right buttons on the EV3 to do this. A short press nudges the motor by a small angle. Holding the button for longer moves it by larger angles more quickly.
Insert a scambled Rubik's Cube into the turntable tray and MindCub3r will start to scan and solve the cube.
MindCub3r may scan the cube up to three times if it is unable to determine the colors at first. If the scanned colors do not result in a valid pattern, MindCub3r will stop after the third attempt and display the message "Scan error" on the EV3 display. If this happens, there may be a number of possible causes. See the troubleshooting section.
If there is a cube present before MindCub3r is ready, the buttons will stay red and the message "Remove cube..." is displayed for you to remove the cube. If this happens even when no cube is present or if MindCub3r does not start to scan the cube when it is inserted, please check that the cables to the infra red and color sensors are connected to the correct ports on the EV3 as shown in by the color coding in the build instructions.
If MindCub3r attempts to scan the cube 3 times and displays the message "Scan error" the following tips may help.
Like MindCuber on Facebook to share your experiences and help each other with troubleshooting.