High performance fibre optic accelerometers

The authors report the design and performance of fully packaged, field ruggedised, high performance fibre optic (FO) accelerometers. Appropriate design considerations have resulted in FO accelerometers with many desirable engineering features which include: (i) high sensitivity (>20 dB re rad/g), (ii) low noise (<1 micro-g root Hz at 1 kHz) (iii) broad frequency response (100 Hz to 14 kHz), (iv) low sensitivity io extraneous measurands (e.g. static pressure sensitivity <-200 dB re rad/mu Pa), (v) small size (<35 gms total, and (vi) low cross-axis sensitivity (<-35dB). Single device or arrays of such devices can be incorporated in many structural and vibration sensing applications at low cost.