Shape Sensing and Structural Health Monitoring

Shape Sensing and Structural Health Monitoring

Adnan Kefal
Real-Time Shape Sensing and Structural Health Monitoring of Composite Structures

Structural health monitoring (SHM) is a very important discipline in the areas of civil, aerospace, marine, automotive engineering, etc. The utilization of SHM allows us to increase both human and environmental safety in conjunction with reduction in maintenance costs. Known as “shape sensing”, real-time reconstruction of a structure’s three-dimensional displacements using a network of in situ strain sensors and measured strains is a vital technology for SHM process. The inverse finite element method (iFEM) is a mechanics-based shape-sensing algorithm shown to be fast, accurate, and robust for usage as a part of SHM systems.

One of our main research areas involves development of mathematically robust and efficient iFEM methodologies to perform real-time monitoring of full-field and three-dimensional structural deformations and stress states of a structure via a network of in situ strain sensors. As depicted in Figure 1, an application of iFEM methodology have been demonstrated by using both fiber optic sensor and strain gauges/rosettes for shape sensing of fiber-reinforced composite materials and sandwich structures.

Figure 1. Real-time displacement monitoring of a wing-shaped structure.

Most recently, we have also introduced coupling of iFEM and peridynamics (PD) for real-time shape sensing and crack propagation monitoring of laminates. As shown in Figure 2, the hybrid iFEM-PD method can account for deformation, stress, and damage states of any sensor-equipped (e.g., FBG sensors) structure in real time without the need for loading knowledge.