This paper explores the application of X-ray-guided magnetic fields for the wireless control of untethered magnetic robots (UMRs) within cerebral vascular phantoms. With a focus on addressing challenges associated with strokes and brain aneurysms, the study aims to enhance neurosurgical procedures by improving precision and maneuverability. Experimental findings showcase the feasibility and effectiveness of this innovative approach in navigating UMRs, characterized by a screw-shaped body and a ferromagnetic core, through complex vascular structures. Cone-beam computed tomography is employed to determine the tomography and provide various reference trajectories for the UMR inside the cerebral vascular phantom. Our motion control experiments show that the X-ray-guided magnetic fields enable the UMR to move along any intended path with an average success rate of 89%, allowing the UMR to move between the left and right common carotid artery to the left and right internal and external carotid artery.

This study focuses on controlling and navigating IRONSperm (i.e., nanoparticle-coated sperm cells) clusters, highlighting their exceptional three-dimensional control capabilities using X-ray-guided magnetic fields. Through thorough exploration of inclination angles within the horizontal plane and actuation distances utilizing a permanent magnet actuator, the study uncovers IRONSperm's resilience to slope angles and its nuanced relationship with actuation distances. A detailed comparison of side and ceiling rolling illustrates the superiority of ceiling rolling on upwardly inclined surfaces, while side rolling excels in maneuverability on descending or horizontal branches. Experimental validation in a trifurcation phantom confirms these findings, emphasizing superior locomotion speed with ceiling rolling. Furthermore, it underscores successful navigation control in different directions, showcasing the potential for open-loop control within enclosed lumens and cavities. Additionally, the study accentuates the groundbreaking ability to localize and control IRONSperm clusters using X-ray-guided magnetic fields, marking a pivotal advancement for microrobotics for biomedical applications.