Hello, here we go with another small Lego drawing project. This time I call it EV3 Doodler. The build is very simple and full instructions are provided. I use the 45544 LEGO® MINDSTORMS® Education EV3 Core Set, but you should be able to build it with the 31313 Home set as well – you only need two large and two small gear wheels not provided in 31313. Also the program is very simple – just one instruction in fact: start both motors in Tank mode and add an endless loop to run it forever… Altering (or better setting) the direction and the speed of the motors will give you virtually endless combinations – each picture will be different. At the beginning you can try speed 100/98 (same direction of both motors) to get a "Trilobite" pattern or 50/-98 (opposite direction - negative value!) to get a "Wormhole" pattern. Each pattern takes about two minutes to complete. Please note the paper should not move under the pen – it must be either fixed to the table by small piece of tape or (if you sheets of paper are large enough) fixed by the Doodler itself. Please feel free to do any modifications you want, have fun and share your creations. Thank you.
PS: Don't worry, the first plotter is still here. I did not disassemble it.