Curing quality monitoring and loading detection of composite structures with embedded capacitive sensor array

Abstract

Structural health monitoring of composite structures from manufacturing to operation is receiving significant attention to ensure their performance and safety. In this paper, capacitive sensor arrays were designed and embedded between adhesively bonded composite laminates for curing quality monitoring during manufacturing and loading detection in operation. A loading inversion method was proposed to quantitatively determine the loading location and value on composite structure. The results showed that the whole curing process of adhesive bonding was successfully monitored. Based on capacitance monitoring, the embedded sensors can capture poor curing quality of adhesively bonded composite laminates due to abnormal curing conditions. The embedded sensors between composite laminates after curing showed perception of external loading. With the evenly distributed sensing capacitors, loading applications on composite laminates were detected. Based on the proposed loading inversion method, loading distribution mapping on the composite laminates was constructed, and the quantitative calculation of the coordinate location and value of loading was achieved. The calculated results agreed well with the actual loading in experiments, affirming the feasibility of the capacitive sensor array and the loading inversion method.