An Active Temperature Compensated Fiber-Optic Fabry–Perot Accelerometer System for Simultaneous Measurement of Vibration and Temperature

Abstract

In this paper, the principle of an active temperature compensated fiber-optic Fabry–Perot accelerometer (FOFPA) system for simultaneous measurement of vibration and temperature is described and experimentally demonstrated. The FOFPA is formed by bonding an all-silica in-line fiber Fabry–Perot etalon to one surface of the triangular cantilever with the lumped mass at the free end for acceleration measurement, and the laser wavelength is feedback controlled with proportional-integral-derivative algorithm for temperature compensation to realize the simultaneous measurement of vibration and temperature. The research results indicate that: 1) the FOPFA system shows a good nonlinearity of about 1.03% with phase sensitivity of about 0.051 rad/g for acceleration measurement; 2) the nonlinearity and sensitivity between the laser wavelength and the operating temperature are about 0.4% and 34.3 pm/ <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$^{\circ}{\rm C}$</tex></formula> , respectively; and 3) the standard deviation of the phase sensitivity over the temperature range of 30 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$^{\circ}{\rm C}$</tex> </formula> –90 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$^{\circ}{\rm C}$</tex></formula> is about 0.002 rad/g.