Micropositioners for microscopy applications based on the stick-slip effect

Abstract

Piezo actuators are widely used for precision positioning purposes where a submicron resolution is needed. Among the possible means to increase the working range of those actuators whose stroke is, depending on the material, usually limited to a small fraction of the actuator length, is a stepping motion of the actuator. We use a stepping motion based on the stick and slip effect in order to achieve a long range while maintaining the advantage of a virtually unlimited resolution. In this paper we introduce miniature x-y-stages dedicated to the manipulation of samples under a microscope. As previous setups and experiments have shown, a parallel kinematic structure for positioning purposes in microscopy or micro assembly is not well suited because x and y motion of the actuators have an influence on each other. A system with a serial kinematic structure has therefore been developed. The proposed device will provide the same capabilities as existing motorized stages, but at a lower cost than manual positioning stages and at a very compact size.