Two dimensional fiber-optical accelerometer

A new type of simple and reliable two-dimensional fiber-optical accelerometer is developed to measure constant (dc) and variable (ac) accelerations simultaneously in two perpendicular directions (vector acceleration) with a linearity error of less than 0.1%. The sensor is based on a deflection of a uniform round elastic cantilever beam sensed by an optical lever and a continuous position optical sensor. The accelerometer has a resolution of 0.3 m s−2, dynamic range of 62 dB, −48 dB crosstalk and a natural frequency ω=1970 rad s−2 , when accelerations of up to 400 m s−2 are measured. The compact shielded construction, high responsivity photosensor and high power photodiode make the proposed sensor stable in the environment of strong electromagnetic interference. Varying the sensor’s parameters, the proposed sensor can be designed to have almost any desired response and sensitivity, and natural frequency.