Microparticle Manipulation using Multiple Untethered Magnetic Micro-Robots on an Electrostatic Surface

This work presents the control of multiple untethered rectilinear magnetic micro-robots (Mag-mu Bots) with dimensions 250 x 130 x 100 mu m(3) actuated by pulsed external magnetic fields, which translate by induced stick-slip motion at speeds of up to 4 mm/s immersed in silicone oil. Multiple Mag-mu Bot control is enabled by employing an array of individually addressable electrostatic surfaces to selectively anchor individual Mag-mu Bots. Coupled parallel and uncoupled serial motion of multiple robots is demonstrated, and they can combine to form an assembly that is also capable of motion. Manipulation of 230 mu m diameter microspheres is also demonstrated cooperatively by two Mag-mu Bots in a fluid environment, and is enhanced when the two Mag-mu Bots are combined. An analysis of the electrostatic anchoring forces and the forces relevant to manipulation is discussed.