Control Of Multiple Magnetic Micro Robots

A magnetic micro robot is a microscopic magnet that is controlled by a system of electromagnetic coils that generate a magnetic field to manipulate the magnetic robot. A major challenge for manipulating multiple magnets at microscale is that the applied field affects the entire workspace, making it difficult to address individual magnets. In this paper, we propose a system where electromagnetic coils are close to the magnets being manipulated to exploit spatial non-uniformities in the magnetic field. Our model considers the magnetic field generated by the electromagnetic coils and the magnetic fields present from neighboring magnetic robots to generate the desired force on each magnet. This approach is demonstrated on a macroscopic, one-dimensional system with two magnets controlled by two electromagnets using visual feedback control. Additionally, simulation results for a linear system with three magnets and three electromagnets are shown. While demonstrated at the macroscale, our results suggest that our methods can be extended for microscale manipulation, where it is advantageous to control multiple identical magnets with global fields.