Remote Control of Untethered Magnetic Robots within a Lumen using X-Ray-Guided Robotic Platform

Until now, the potential of untethered magnetic robots (UMRs), propelled by external time-periodic magnetic fields, has been hindered by the limitations of wireless manipulation systems or noninvasive imaging techniques combined. The need for simultaneous actuation and noninvasive localization imposes a strict constraint on both functionalities. This study addresses this challenge by substantiating the feasibility through experimental validation, showcasing the direct teleoperation of UMRs within a fluid-filled lumen. This teleoperation capability is facilitated by a scalable X-ray-guided robotic platform, extendable to match the dimensions required for in vivo applications, marking a noteworthy advancement. Our methodology is demonstrated by teleoperating a 12-mm-long screw-shaped UMR (5 mm in diameter) within a bifurcated lumen, filled with blood. This navigation is achieved using controlled rotating magnetic fields, guided by real-time X-ray Fluoroscopy images. Incorporating a two-degree-of-freedom control system, we demonstrate the operator's capability to use X-ray Fluoroscopy images to keep the UMR coupled with the external field during wireless teleoperations, resulting in a success rate of 76.6% when moving along the intended pathways, with a mean absolute position error of 1.6 ± 2.1 mm.