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Compound Of Six Octahedra
The compound of six octahedra has two forms. One form is a symmetric arrangement of 6 octahedra, considered as square bipyramid. It is a dual of a special case of the compound of 6 cubes with rotational freedom. Another form is a dual of another compound of six cubes. See also * Compound of three octahedra * Compound of five octahedra * Compound of four octahedra *Compound of six cubes A compound of six cubes has two forms. One form is a symmetric arrangement of six cubes, considered as square prisms. It is a special case of the compound of six cubes with rotational freedom. Another form is not related to a compound of six cu ... References Octahedron6-Compound Polyhedral compounds {{polyhedron-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octahedra
In geometry, an octahedron (plural: octahedra, octahedrons) is a polyhedron with eight faces. The term is most commonly used to refer to the regular octahedron, a Platonic solid composed of eight equilateral triangles, four of which meet at each vertex. A regular octahedron is the dual polyhedron of a cube. It is a rectified tetrahedron. It is a square bipyramid in any of three orthogonal orientations. It is also a triangular antiprism in any of four orientations. An octahedron is the three-dimensional case of the more general concept of a cross polytope. A regular octahedron is a 3-ball in the Manhattan () metric. Regular octahedron Dimensions If the edge length of a regular octahedron is ''a'', the radius of a circumscribed sphere (one that touches the octahedron at all vertices) is :r_u = \frac a \approx 0.707 \cdot a and the radius of an inscribed sphere (tangent to each of the octahedron's faces) is :r_i = \frac a \approx 0.408\cdot a while the midradius, which tou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compound Of Six Cubes With Rotational Freedom
This uniform polyhedron compound is a symmetric arrangement of 6 cubes, considered as square prisms. It can be constructed by superimposing six identical cubes, and then rotating them in pairs about the three axes that pass through the centres of two opposite cubic faces. Each cube is rotated by an equal (and opposite, within a pair) angle ''θ''. When ''θ'' = 0, all six cubes coincide. When ''θ'' is 45 degrees, the cubes coincide in pairs yielding (two superimposed copies of) the compound of three cubes. Cartesian coordinates Cartesian coordinates A Cartesian coordinate system (, ) in a plane is a coordinate system that specifies each point uniquely by a pair of numerical coordinates, which are the signed distances to the point from two fixed perpendicular oriented lines, measured in t ... for the vertices of this compound are all the permutations of :(\pm(\cos(\theta)+\sin(\theta)), \pm(\cos(\theta)-\sin(\theta)), \pm1). : Gallery File:Cube.stl, ''θ'' = 0° F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compound Of Six Cubes
A compound of six cubes has two forms. One form is a symmetric arrangement of six cubes, considered as square prisms. It is a special case of the compound of six cubes with rotational freedom. Another form is not related to a compound of six cubes with rotational freedom. See also *Compound of three cubes *Compound of five cubes *Compound of four cubes The compound of four cubes or Bakos compound is a face-transitive polyhedron compound of four cubes with octahedral symmetry. It is the dual of the compound of four octahedra. Its surface area is 687/77 square lengths of the edge. Its Cartesian ... * Compound of six octahedra References Polyhedral compounds {{polyhedron-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compound Of Three Octahedra
In mathematics, the compound of three octahedra or octahedron 3-compound is a polyhedral compound formed from three regular octahedra, all sharing a common center but rotated with respect to each other. Although appearing earlier in the mathematical literature, it was rediscovered and popularized by M. C. Escher, who used it in the central image of his 1948 woodcut ''Stars''. Construction A regular octahedron can be circumscribed around a cube in such a way that the eight edges of two opposite squares of the cube lie on the eight faces of the octahedron. The three octahedra formed in this way from the three pairs of opposite cube squares form the compound of three octahedra.. The eight cube vertices are the same as the eight points in the compound where three edges cross each other. Each of the octahedron edges that participates in these triple crossings is divided by the crossing point in the ratio 1: . The remaining octahedron edges cross each other in pairs, within the interior ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compound Of Five Octahedra
The compound of five octahedra is one of the five regular polyhedron compounds. This polyhedron can be seen as either a polyhedral stellation or a compound. This compound was first described by Edmund Hess in 1876. It is unique among the regular compounds for not having a regular convex hull. As a stellation It is the second stellation of the icosahedron, and given as Wenninger model index 23. It can be constructed by a rhombic triacontahedron with rhombic-based pyramids added to all the faces, as shown by the five colored model image. (This construction does not generate the ''regular'' compound of five octahedra, but shares the same topology and can be smoothly deformed into the regular compound.) It has a density of greater than 1. As a compound It can also be seen as a polyhedral compound of five octahedra arranged in icosahedral symmetry (Ih). The spherical and stereographic projections of this compound look the same as those of the disdyakis triacontahedron. But ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compound Of Four Octahedra
The compound of four octahedra is a uniform polyhedron compound. It's composed of a symmetric arrangement of 4 octahedra, considered as triangular antiprisms. It can be constructed by superimposing four identical octahedra, and then rotating each by 60 degrees about a separate axis (that passes through the centres of two opposite octahedral faces). Its dual is the compound of four cubes. Cartesian coordinates Cartesian coordinates for the vertices of this compound are all the permutations of : (±2, ±1, ±2) See also * Compound of three octahedra * Compound of five octahedra * Compound of ten octahedra * Compound of twenty octahedra *Compound of four cubes The compound of four cubes or Bakos compound is a face-transitive polyhedron compound of four cubes with octahedral symmetry. It is the dual of the compound of four octahedra. Its surface area is 687/77 square lengths of the edge. Its Cartesian c ... References *. Polyhedral compounds {{polyhedron-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compound Of Six Cubes
A compound of six cubes has two forms. One form is a symmetric arrangement of six cubes, considered as square prisms. It is a special case of the compound of six cubes with rotational freedom. Another form is not related to a compound of six cubes with rotational freedom. See also *Compound of three cubes *Compound of five cubes *Compound of four cubes The compound of four cubes or Bakos compound is a face-transitive polyhedron compound of four cubes with octahedral symmetry. It is the dual of the compound of four octahedra. Its surface area is 687/77 square lengths of the edge. Its Cartesian ... * Compound of six octahedra References Polyhedral compounds {{polyhedron-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
