Structural Health Monitoring Techniques for Aerospace Applications

Recently, structural health monitoring and damage detection has reemerged as an area of interest for the mechanical, automotive, and aerospace industry. Increasingly, there is a need to develop in-service and on-line health monitoring techniques. Such techniques allow systems and structures to monitor their own structural integrity while in operation and throughout their life and are useful not only to improve reliability, but also to reduce maintenance and inspection costs. Although, there has been an extensive amount of work performed in the area of structural health monitoring and damage sensing technologies, most of the existing methodologies suffer from defects that include low sensitivities, complex FE models that may take long periods of time to calibrate, and modal truncations that may or may not lead to accurate predictions. In this paper, the possibility of addressing this problem with different techniques is proposed and applied to both numerical and experimental test cases. This work constitutes a first contribution toward the goal of integrating these techniques for an efficient and robust real-time health monitoring technique. The first approach is a novel application of an adaptive control technique for non-destructive monitoring and evaluation for structural integrity of aerospace structures, while the second method is based on a structural updating technique predicting the evaluation of the changes of the dynamic characteristics of the structures in the frequency domain. A numerical and experimental investigation of the above methodologies will be carried out taking into account different problems in system dynamics.