Kalman Filter based Neutral Axis tracking for damage detection in composites structures under changing axial loading conditions

This paper demonstrates the development of a Kalman Filter (KF) based NA tracking strategy under different loading conditions. The methodology was employed on a composite beam instrumented with fiber optic strain sensors. The stable NA tracking under changing loading conditions allows the application of the NA as a damage sensitive feature. The change in NA location is used to detect delamination in the beam. The method has been validated through a numerical model and experiments. The results show that the novel formulation of the KF for NA tracking allows more robust use of NA location as a damage sensitive feature in a wider range of applications.