Interferometric fiber optic accelerometer

Abstract

A push-pull fiber optic accelerometer using a Michelson interferometer to detect the surface strains produced on a pair of coaxial flexing disks is described. The sensitivity below the disk's fundamental resonance of 2.45 kHz is 50 radians/g. The fractional phase change per unit force A4/AF is 5.9 x 106 W1 . A noteworthy feature of this sensor is that the 5 meter sensing coils comprising the legs of the interferometer are totally internal to the sensor structure and thus are not exposed to platform or fluid under investigation.