Abstract: An array of plate-like elements is retained by endless filaments looped on the elements to form migrating hinges between individual elements and other elements adjoining same. Grooves are formed in the surfaces of each plate, the grooves being in two groups, with the members of each group being mutually parallel, and the grooves of each surface being in overlying registration. The filaments lie within the grooves in a selected pattern, with filaments forming anchor points at plate sides at which the filament wraps around the side of the plate to enter a groove from the other group of grooves on the opposite side of the plate, and hinge points at plate sides where the filament passes from one plate to an abutting plate, proceeding from one surface to the opposite surface in doing so. Manipulation of the resulting array allows two such plates to rotate mutually about an axis defined by hinge points lying on their abutting sides.