Development of temperature-insensitive fibre bragg grating pressure transducer

In this work, the development of an aluminium diaphragm fibre Bragg grating (FBG) pressure transducer with temperature compensation strategy is presented. One of the big challenges for the applications of an FBG pressure transducer is the inconsistency in output wavelength due to temperature variations. This situation leads to huge uncertainties in pressure readings. The aim of this article is to present how to eliminate the effects of temperature variations to the pressure measurements. Two FBG sensors were used; namely as FBG 1 and FBG 2. These FBGs were bonded each one on the diaphragm and base surface of the pressure transducer. The strain readings by the FBG on the diaphragm was normalized by the FBG reference which was pasted on the transducer's base. This temperature compensation strategy was successful and the FBG pressure transducer was proven to be suitable for pressure measurement of gas with an average error of 2.32%. Besides, the result also shows that, for pressure ranging from 0 to 0.5 MPa, the FBG pressure transduced has sensitivity of 2.8485 nm/MPa with linear fitting coefficient of 99.97%.