Planar Navigation Algorithm of Magnetic Dipole Microrobot by Three External Electromagnets

Recently, magnetic microrobots have attracted much attention in biomedical applications due to their minimally invasive features. One of the challenges in this field is about in-vivo autonomous control of microrobots to reach a predefined target. In concern of the submillimeter size of the microrobots, their position and orientation are controlled by an external magnetic field which is generated by permanent magnets or electromagnets. One of the advantages of using electromagnets to produce an external magnetic field is the ability of controlling the magnitude and orientation of the magnetic field by manipulating the electrical current of each electromagnet. In this study, by using Maxwell’s equations and considering the microrobot as a point dipole, the exerted force and torque relations are driven as a function of electromagnets’ electrical current. Moreover, a navigation algorithm is proposed to guide the robot through unknown obstacles without planning the whole path. Furthermore, the driven equations and designed algorithms are validated by simulating the microrobot’s motion using MATLAB software, which confirms the effectiveness of using three electromagnets to control an electromagnet microrobot’s planer motion.