A Fiber Optic Sensor Measurement System for a Levitated Sphere-Shaped Superconducting Rotor

A fiber optic sensor measurement system for superconducting rotor instrument was presented. The system included displacement fiber optic sensor, speed fiber optic sensor, motor control fiber optic sensor and signal readout patterns. It not only could measure suspension micro-displacement and rotation speed of rotor, but generate some accurately drive signals to accelerate the rotor. Experimental results performed at 4.2 K showed that the displacement measurement resolution was 10 $\mu{\rm m}$ and drive signals were good. This work has demonstrated that the fiber optic measurement system could accurately monitor rotor suspension position and provide drive signals for rotor spun up.