A new type fiber-optic accelerometer

A novel all-metal fiber-optic accelerometer with Michelson interferometric configuration is proposed, using mass blocks and flexible reed structure. The sensing arm is configured to directly transform the applied acceleration to fiber deformation in axial direction, which increases the acceleration sensitivity of the sensor. The axis of the reference arm is set orthogonal to that of the sensing arm in order to make it insensitive to applied acceleration, and thus decrease the phase noise of the sensor. Using the flexible reed of 1mm thick and the mass block of 208g, an acceleration sensitivity of 556.7rad/g(54.9dB) is achieved by this structure. In the case of 10-4 rad/rt Hz(100Hz) noise floor, the minimum detectable acceleration is 200ng/rt Hz.