Fig. 1: Conventional and MRI-compatible electromagnetic direct current motors.
From: MRI-compatible electromagnetic servomotor for image-guided medical robotics
a Schematic of conventional direct current (DC) motor. Red labels denote components that are inherently incompatible near strong magnetic fields. b Schematic of MRI-compatible DC motor concept. Static field of main superconducting magnet is used instead of permanent magnets for torque generation. All magnetic and ferromagnetic materials are replaced by non-magnetic counterparts (blue text).
