(3) Design of sphere_Designing a sphere using [Spherical octacu]


 This time, let's design a simple spherical surface using the vertices of a regular polyhedron printed on a bubble.

 

① First, use the parish [spherical octacu] to draw 8 points, and distinguish the 4 points that make up a regular tetrahedron with the same color. After drawing a spherical tetrahedron by connecting the 4 blue points, I drew a design like the photo below with the 4 red points.



② Using the [spherical octacu] tool, mark the eight vertices that make up a cube.


Using a great atom, draw a great circle connecting two adjacent vertices, but only up to 1/3 of the way from the vertex.

Draw two circles as shown in the picture below.


If you draw a great circle like the above on all the faces of the cube, it is complete.


 

③ Using the parish [spherical octacu], mark the 6 vertices of the regular octahedron. Then, mark points at the same distance to the left and right of each vertex (in a different direction from the neighboring vertices). <Refer to the picture below>


Draw an arc of great circle from one vertex of a regular octahedron to the left point of the adjacent vertex and the right point of the opposite vertex (but do not connect the points completely).


If you draw an arc of a circle at every vertex, you will end up with a soccer ball design like the picture below.


You can draw various designs by referring to the book ‘design of sphere and Regular Polyhedron’.

 

In the next part, we will draw a spherical design using the vertices of the regular dodecahedron and regular icosahedron using the parish [spherical icodo].

 

Ⓒ msolid

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