Abstract
Some methods are discussed to improve positioning accuracy and realizing finer positioning resolution using leadscrew mechanisms. Recent trend on current positioning technology is overviewed briefly, and accuracy level imposed on leadscrew mechanisms is clarified. Frictional property in starting and reversing motion is discussed on a sliding leadscrew and a ball screw. It is shown that a ball screw has nonlinear elastic property within microscopic range. Next, a proper control method is discussed for a positioning mechanism using a ball screw with such nonlinear elastic property. And a method of intentionally attaching the elastic property to a sliding leadscrew is proposed. Moreover, a differential ball screw is introduced to realize finer resolution.
