Ravigneaux gear set--a type of planetary gear system.There are STL files for 3d printing; DXF files for laser cutting. Ignore the OBJ and FBX format files, they are only used to meet the platform's requirement.You can use this mechanical model to help a child or student to understand how planetary gear set runs. At the same time, it is a simple gearbox.After you make the parts, you can try to fix any of the parts: the sun gear, planetary gear, or the ring gear, to get different results.Video: https://youtu.be/xDm8P7RhWvc