Synetic Structures by Rick Flowerday
A strong, lightweight structural system wherein curved structural elements are tangentially joined. Compressive forces are distributed in a near continuous manner throughout the matrix. Tensile forces in the system are present primarily to brace, support and pre-stress the compression net. Synetic designs are scaleable from molecular through architectural levels, finding many applications in dome shaped and spherical structures. The system also provides a force interaction model that is applicable to a broad array of real and theoretical problems.
The Archex Variation by Richard Hawkins
The archex variation simply substitutes quadrants (90 degree arcs) for unit edge lengths in the IVM (isotropic vector matrix).
It is my own innovation and one which I have contemplated for many years. The term "archex" was coined by Karl Erickson in our discussions on synergetics-l mailing list, and refers to the six 90 degree arcs which when joined at 90 degrees to each other form a continous loop analogous to the hexagonal grouping of edges in th VE (vector equilibrium). See archex.JPEG for a view of one archex inscribed within a cube.
The archex loop has three peaks and three valleys so its' design facilitates the conversion of axial to linear motion and vice-versa (see archex_toy.MOV).
The VE (without radials) can be viewed as 4 hexagonal planes; similarly, the archex VE is 4 archex loops. The arc hex loop can be used in place of the hexagonal face of other polyhedra in the IVM.
The archex tetrakai is formed from 8 archex loops (see archex_tetrakai).
The archex tetrakai and archex VE can be combined to form a jitterbug variation (archex_jitterbug.MOV).
This design may have some practical application, any ideas?
One of the most interesting discoveries in my exploration of the archex topological forms is the precessional relationship between the archex loops and arc-triangles of the archex VE.
If an armature with its' pivot point at center of gravity is rotated tracking through the archex loops of the archex VE, another armature fixed at 90 degrees to the first will track the arc-triangles (see archex_precession.MOV).