A rhombic dodecahedron keel was created in Moi, using the formulas in the link in post 7.
The keel is the 3D combination of 3 rhombi. The keel for the rhombic dodecahedron has certain specific dimensions. Other "non-efficient" keels are possible.
R = (outer) radius of hexagon, (or hexagon prism). Set to value of 4 units.
height_min = R * sqrt(2) / 4 (This is the height above the top of the hexagon prism, and is half the height of the keel.) (sqrt(2) is the diagonal of a unit square.)
d is the diagonal of the hexagon, with one vertex in between. d = R*sqrt(3). d is also one of the diagonals of the rhombi.
For a_min, 2*a is the other diagonal of the rhombi. 2*a = R*sqrt(3) / sqrt(2)
The Maraldi angle is the obtuse angle of the rhombi_min. Angle is about 109.4712 degrees. (109degrees, 28 minutes, 16 seconds.)
I had to use Michael's old Angle script to measure the angle.
Have had trouble using the angle Dim command, in 3D view, with angles that are not orthogonal in other views...
The 3D keel gives the illusion of viewing a cube.
- Brian
Two planes through two of these rhombi, intersect at an angle of 120 degrees. (Used two lines perpendicular to the intersection edge, to measure angle.)
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