Vibration-based skin damage statistical detection and restoration assessment in a stiffened aircraft panel

The combined problem of skin damage detection and restoration quality assessment in lightweight stiffened aircraft panels via vibration testing is considered. Two methods that employ statistical estimation and hypothesis testing procedures and are capable of accounting for experimental uncertainty are introduced. The first is parametric and employs natural frequency and damping ratio interval estimates. The second is non-parametric and employs coherence function interval estimates. The methods’ effectiveness is assessed through laboratory experiments with a stiffened aircraft panel. The results of the study indicate the feasibility of the vibration-based methodology for tackling both the skin damage detection and restoration quality assessment problems. It is also shown that the first method is effective for the skin damage detection problem, while the second for both the skin damage detection and restoration quality assessment problems.