Design of improved differential decoupling method of temperature sensitivity and piezoresistivity for CFRPs

Abstract

Based on the deformation monitoring of engineering structures in variable temperature environment, error of differential decoupling method of Carbon fiber reinforced plastic sensors was studied. The results reveals that the individual differences of the temperature sensitivities in carbon fiber composites causes obvious error in strain measuring, which would increase with the increase of the differences of their temperature sensitivities. Improved differential decoupling method was put forward by setting the constant current power supplied with different excitation. This method is able to eliminate the error caused by differences both in the temperature sensitivities and the initial resistances, and provides a high gauge factor. The effectiveness of the improved differential decoupling method was verified experimentally.