Design and characterization of solid articulated four axes microrobot for microfactory applications

Abstract

In this paper, we present the design and experimental evaluation of a 3-dimensional microrobot called Solid Articulated Four Axes Microrobot (sAFAM). The sAFAM is fabricated using Microelectromechanical System (MEMS) technology, then assembled to achieve out-of-plane motion and perform micro and nano manipulation tasks relevant to future microfactories such as pick and place and applying controlled forces onto the environment. The paper discusses the design, fabrication and assembly processes for constructing sAFAM. Four in-plane electrothermal actuators drive the end-effector through a complaint mechanical coupling. The microrobot structure was simulated by finite element analysis (FEA), predicting a 13 μm × 47 μm × 115 μm workspace and verifying appropriate concentration of stresses during actuation. The resolution, repeatability, and workspace of the microrobot were then measured experimentally via optical microscopy and laser ranging, indicating a 16 μm × 20 μm × 118 μm dimension workspace. Experiments also indicate that the motion resolution and repeatability of the microrobot varies depending on the location of the end-effector in space, but generally range between 20 nm (minimum) and 150 nm (maximum). With FEA simulation result, the force output of sAFAM falls in the range of tens of micro Newtons. Thus, sAFAM has the potential for future use as an assist micro/nano manipulation tool in the scanning electron microscope (SEM) or in conjunction with an atomic force microscope (AFM).