Untethered Magnetic Robots (UMRs) offer the potential for minimally invasive navigation through complex vascular networks, particularly in neurosurgical contexts. This research investigates the behavior
and control of helical UMRs as they traverse bifurcated cerebral vessels under the influence of a rotating permanent magnet (RPM). A theoretical velocity profile and corresponding equation of motion were developed to model the UMR’s propulsion in low Reynolds number flow.
Experimental work focused on navigation through T- and Y-shaped bifurcations using vascular phantoms. Challenges in trajectory accuracy and branch selection were addressed through a pre-steering control strategy, which anticipates directional changes by adjusting the RPM orientation prior to bifurcation entry. Results demonstrate a significant improvement in traversal success rates from 50% under standard control to 90% with presteering.
These findings highlight the importance of anticipatory control in enhancing UMR navigation and lay the groundwork for future closed-loop systems and clinical translation.