The present invention is directed to structures and methods of fabricating electromechanical memory cells having nanotube crossbar elements. Using the twisted pair of wires in the selected gauge and pitch results in significant cost reductions; less wire is needed to achieve the same heating capacity. The steering signals minimize an error function having parameters that include a measure of a cross-line position error and a measure of data quality. The representative vector calculating unit calculates a predetermined number of representative vectors that represent a plurality of images contained in the group of sequential images.