Design of a Novel Vertical Motion Piezoworm Positioner

Abstract

Piezoelectric-based positioners are incorporated into stereotaxic devices for microsurgery, scanning tunneling microscopes for the manipulation of atomic and molecular-scale structures, nanomanipulator systems for cell microinjection and machine tools for semiconductor-based manufacturing. This wide range of applications requires the design and development of large load capacity, long stroke and compact positioning stages without compromising high speed and precision. Although several precision positioning systems have been developed for planar motion, most are neither suitable nor readily lend themselves to provide long travel range with large load capacity in vertical axis because of their weights, size, design and embedded actuators. To address the limitations of the traditional technologies, a novel positioner is being developed specifically for vertical axis motion based on a piezoworm arrangement in flexure frames. Analytical calculations and finite element analysis are used to optimize the design of the lifting platform to provide maximum thrust force while maintaining a compact size. To make a stage frame more compact, the actuator is integrated into the stage body which mainly consists of a moveable component outside a rigid frame. The clamps are designed such that no power is needed to maintain a fixed vertical position, holding the payload against the force of gravity.