A novel weight measurement method based on birefringence in fiber Bragg gratings

Abstract

Unlike the usual wavelength modulation principle of fiber Bragg grating (FBG) sensors, a novel weight sensor based on birefringence in FBG is proposed in this paper. The creation of the birefringence is based on the different stresses of the two orthogonal directions in the fiber core cross-section. If weight is applied on an FBG in the radial direction, two reflection spectra with different polarization states which can be observed by an optical spectrum analyzer will occur. An experimental prototype is set up and the measurement principle is described in this paper. Preliminary experimental results indicate that the proposed measurement method is very suitable for the application of heavy weight measurement in the range of 20 tons, especially for vehicle load monitoring in highway charge-by-weight systems. The sensitivity of weight measurement is be estimated to be about 5 kg.

Keywords

fiber Bragg grating (FBG) / birefringence / vehicle weighing / charge-by-weight

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant Nos. 50575111, 60704026), National High Technology Research and Development Program of the Ministry of Science and Technology of China (No. 2007AA09Z102).

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg