US Patent 8172036 Apparatus and method for providing acoustic metamaterial

A method for fabricating an acoustic metamaterial may include providing a planar pattern of springs arranged in columns and rows and separated from each other by interconnection nodes, providing a planar pattern of mass units separated from each other by a distance corresponding to a distance between the interconnection nodes, providing an array of vertically oriented springs separated from each other by the distance between the interconnection nodes, and aligning and joining the planar pattern of springs, the planar pattern of mass units and the array of vertically oriented springs to form a layer of unit cells.