A Two-Dimensional Manipulation Method for a Magnetic Microrobot with a Large Region of Interest Using a Triad of Electromagnetic Coils

This paper proposes an effective method to manipulate the 2D motions of a magnetic small-scale robot (microrobot) within a relatively large working area using a triad of electromagnetic coils (TEC). The TEC is a combination of three identical circular coils placed at the vertices of an equilateral triangle. Since it is geometrically compact and requires only three control variables (input currents), the TEC can be effectively used to generate various magnetic fields that can be used to maneuver various functional microrobots. In this paper, we established several equations to calculate the input currents of the TEC required to move a microrobot along a designated pathway effectively and precisely. We also constructed an experimental setup to demonstrate and validate the controlled motions of the microrobot using the proposed method. The results showed that the proposed method can effectively improve the TEC’s practical working area (region of interest) for manipulating the microrobot, which can possibly be applied to biomedical and biological applications, including minimally invasive surgery, targeted drug and cargo delivery, microfluidic control, etc.