Design and Actuation of a Multipole Ring Magnet for Navigating Endovascular Magnetic Instruments

This paper presents the design and analysis of a compact magnetic field generator for robotic navigation of magnetic endovascular instruments in clinical settings. The system features eight symmetrically arranged permanent magnets in a ring configuration, maximizing magnetic field uniformity and aperture size for X-ray transmission while minimizing spatial footprint and magnet motion for uninterrupted fluoroscopy imaging. The rationale behind the design of the system is explained through analytical considerations of magnetic field distribution. In vitro demonstrations inside perfused biomimetic phantoms confirm the system's capability for 3D steering of flow-driven magnetic microcatheters, opening a path for pre-clinical testing.