Submerged robotic micromanipulation and dielectrophoretic micro-object release

The development of new hybrid microsystems needs new technologies which are able to perform assembly of small micro-objects. Now, the current micromanipulation technologies are still unreliable for micro-objects which typical size is down to hundred micrometers. Consequently, the study and the development of innovative artificial microobject manipulation strategies in these dimensions is particularly relevant. As presented in the literature, micromanipulations are perturbed by the adhesion and surface forces which depend on surrounding mediums. We propose to perform micro-assembly tasks in liquid medium, because adhesion and surface forces applied on submerged micro-objects are less important than in air. The comparative analysis of micro-forces in air and in liquid is presented in this paper. Although the micro-forces reduce in liquid, they stay disturbed the micro-objects release. Thus, we propose to extend the dielectrophoresis micromanipulation principles which are currently done in the biological micromanipulation to submerged artificial objects micro-assembly. The negative dielectrophoresis principle is used to release a micro-object grasped with a micro-gripper. Physical principle and first experimentations is presented in this article. Further works will focus on the optimization of the principle, and on the micro-object release modelling and control.