Cycloidal Speed Reducer in OpenSCAD

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This OpenSCAD file creates a cycloidal speed reducer based on Syvwlch and WilliamAAdams' request. Intended more as an example of an interesting mechanism than a practical device, it can be animated using OpenSCAD or printed into STLs for 3D printing. For laser cutting, DXF files are also available with extra holes to allow pieces alignment and assembly. The design is based on M.F. Hill's 1928 patent "Internal Rotor" (number 1,682,563), featuring offset hypocycloid profiles. However, the motivated user can modify the code to create epicycloid-based profiles or optimize the code for better functionality. The speed reducer can also be used as a pump with suitable adjustments. Note that there might be slight interference at the tips of internal rotor lobes when printed due to minimum clearance around shafts, but laser cutting should provide ample clearance.