MR Compatibility of Mechatronic Devices: Design Criteria

Criteria to design MR (Magnetic Resonance) compatible mechatronic devices, e.g., surgical robots, are discussed. Some of critical interactions between MRI and mechatronic devices are discussed. Experimental results of the effects from several passive and active mechanical elements are demonstrated. Some passive elements, e.g., ball screw and linear guide have point contacts therefore, they are required to be made of hard smooth surfaces. Both beryllium-copper and a new stainless steel were examined. Effects from ultrasonic motor were also examined. They didn’t show any image shift. Significant degradation of signal noise ratio was not observed, too. Based on these results, we developed a five d.o.f. MR compatible surgical manipulator.