Micromanipulation applying local machining station method

Abstract

This paper deals with an application of Local Machining Station (LMS) method to micromanipulation in order to improve the positioning performance. Small mobile devices, “AZARASHI (seal) Mechanism” were used as positioning devices. A micromanipulation system with multiple degrees of freedom (DOFs) was built by combining AZARASHI Mechanism. It consists of an L-shaped device for the x-, y- and θ-motions, and one-DOF device in the z-motion. By the visual feedback, a glass bead was placed with a fixed sequence. In order to grasp a glass bead with a diameter of 60-70 μm, tweezers equipped bimorph piezoelectric actuators was used. While the bead was trapped and placed by moving the stage, lens-magnification was alternated to expand a view area or make resolution fine. The positioning performance for the manipulation applying LMS method was measured. The positioning accuracy was less than 1 pixel of capturing camera. Error budget is also discussed. Although positioning accuracy by LMS method was better than that without LMS, adhesion of a bead on one of the tweezers by Van der Waal's force or surface tension disturbed positioning process.