Patent attributes
The present invention relates to a monitoring device for a rotating body, which can accurately measure signals from a fiber Bragg grating sensor provided on the rotating body by compensating a transmission loss variation and a distortion of the sensor signals. A rotation-side optical fiber has at least one deformation sensor at a portion thereof and a reference sensor at one end thereof. The sensors are made by forming a Bragg grating in the rotation-side optical fiber. A fixed-side optical fiber is mounted to the fixed body so as to be opposed to the one end of the rotation-side optical fiber. A signal processing unit detects a deformation of the rotating body by subtracting a signal corresponding to the light reflected from the reference sensor from a signal corresponding to the light reflected from the deformation sensor.
