Independent Control of Identical Magnetic Robots in a Plane

Abstract

Magnetic micro robots have been proposed for applications in minimally invasive surgery and cell manipulation in biological experiments. A major challenge of manipulating multiple magnets at the microscale is addressing them individually using global magnetic fields. In particular, it is difficult to control magnets, which are identical in all aspects. This work proposes a force control method to manipulate multiple magnets by utilizing spatially varying gradients of the magnetic field with stationary electromagnetic coils. This approach is demonstrated using simulations and experiments on a macroscopic, planar system with two identical magnets controlled by four stationary electromagnets using visual feedback control. Simulation results show that this control strategy is also relevant for microscale systems by simulating a low Reynolds number environment.