Precise Positioner Utilizing Rapid Deformations of a Piezoelectric Element

This paper describes a new method of precise positioning using piezoelectric elements. The method utilizes the friction force between the object to be moved and the base plane, and the reaction of the inertial force caused by a rapid deformation of a piezoelectric element. The configuration of this positioning mechanism is simple : an element for inertial mass is connected to the object to be moved by a piezoelectric element. Through controlling the rapid deformation of the piezoelectric element, we can control the inertial force, which causes a controlled step-like movement of some nanometers up to some ten-micrometers. Repeating this stepping action, it is possible to move the positioner with a velocity of more than one millimeter per second. Applying a sensor feedback to the mechanism, almost the same resolution and accuracy as the sensor can be achieved in position control. This method of positioning also realizes a remarkably simple 3-axial precise positioning table.