Today’s invention is a chain-like structural component. Two of these are indicated in the diagram. As shown, the two parts are free to rotate, relative to each other, in any direction. When these are pressed together, so that the two pairs of cylinders bear on each other, the links together act as a single rod.
Using many such chain links would allow rigid structures to be quickly extended and collapsed -for ease eg of transport (imagine a bicycle frame made of these and collapsible into a carrier bag).
Corner units, consisting of multi-ended links, could also be created to provide 3-D arrangements as well as purely linear ones. The links might be connected by springs, in order to add tensile strength to the rods which they form.