## Rhomboid

This sculpture is a polyhedral linkage with accurate articulation.

You probably already know of the two-dimensional shape known as the rhombus, or parallelogram. In a rhombus, opposite edges remain parallel. Well, can you imagine the three-dimensional version of a rhombus? In the three-dimensional case it would be opposite planes that remain parallel! In fact, this shape is known to mathematics. It goes by the name rhomboid, rhombohedron, or parallelepiped. That’s the underlying idea for this sculpture, an embodiment of of a rhomboid.

This sculpture is designed to be picked up and played with. Expand it, collapse it, skew it. See how many different forms it can take. Notice the extents of the range of motion of the linkages. See if you can identify groups of edges which remain parallel. Does the volume change as you transform its proportions?