Abstract
This research aimed to realize a system to detect delamination damage in carbon fiber reinforced plastics (CFRP)composite laminates for health monitoring of composite structures. Our previous system consisted of macro fiber composite (MFC) actuators and fiber Bragg grating (FBG) sensors on both sides of a CFRP laminate, and this system propagated multiple modes of Lamb waves in it and identified all the modes by synchronized actuation of two MFCs and sensing with two FBGs on both sides. However, it was not practical to attach them at the same positions of both sides in an actual large composite structure. In this research, therefore we attempted to construct a new system separating modes by using two MFCs and an FBG on only one side of an intact CFRP laminate. The two same MFCs were separately attached in the same line and they were driven by the same frequency voltage signal having a different initial time and phase. In this report, the authors simulated the system with a finite element analysis and conducted experiments to investigate the feasibility of this mode separation method. As a result, we found the method could separate them, which meant that particular modes were strjpnthened or weakened depending on the initial conditions.
