An untethered magnetically actuated micro-robot capable of motion on arbitrary surfaces

摘要

This work presents an untethered magnetic micro- robot with dimensions of 250 <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mum</i> x 130 <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mum</i> x 100 <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">mum</i> . The robot is composed entirely of neodymium-iron-boron fabricated using laser micro-machining. It is actuated by a system of five macro-scale electromagnets. By using electromagnets to control the robot, the surface on which the robot operates need not be specialized, smooth, patterned, nor conductive. Two control methods, both based on periodic excitation of the robot, are attempted and compared. Controllable motion at speeds in excess of 2.8 mm/s, approximately 11 body lengths per second, is demonstrated. Teleoperated motion in two dimensions is shown, and the assembly of micro-particles is demonstrated underwater. Potential future applications include micro-scale manipulation, fabrication, and assembly of micro-systems.