Joined octa pyramids create tetrathedrons
between the octahedrons in a unique truss system. Buckminster
Fuller termed it the "Octet Truss".
Shown here as a hub-strut wood structure with proportions for 2 x 4 lumber. The design can also use steel or aluminum tube struts with different connection methods.
See also: Tetra Pyramid Array | Octa-Tetra Truss | Octa-Tetra Variations 1 | Octa-Tetra Variations 2 | Pyramids