Johnson Polyhedra Duals by pmoews

Last crawled date: 3 years ago

Here are the 92 Duals of the Johnson Polyhedra, see thing:16508. They were constructed by the method described in thing:30958, Duals of Polyhedra.
You can read about duals on Wikipedia or on the dual page at George Hart's Virtual Polyhedra Site, see
http://www.georgehart.com/virtual-polyhedra/duality.html
Simply put if object A is transformed to object B by some process and if B is tranformed back to A by the same process, A and B are duals. In this case A and B are different but related polyhedra. The vertices of A become the faces of B and vice versa.
Ninety-two are too many polyhedra to show here though all are printable. It seemed better to present a few examples of the orginal Johnson polyhedra together with their duals to show how the process works. Compounds of the duals and their polyhedra are included as they are helpful in understanding the relationships. In the compounds the vertices of the original polyhedron protrude from the faces of the dual.
Stl files are:
Example 1: J9.stl, J9_dual.stl and compound_j9.stl
Example 2: J12.stl, J12_dual.stl and compound_j12.stl
Example 3: J16.stl, J16_dual.stl and compound_j16.stl
The fortran program that produced the openSCAD programs and the openSCAD programs that generated the duals are included in johnson_duals_scad.zip. The stl files of all the duals are included in johnson_duals_stl.zip