It is important to detect the incipient damage at the first available signal to take necessary steps for the well being of the structure. This needs to keep track of the changes in the stiffness and other significant mechanical properties of the critical members in a structure in real time. Damage beyond a certain level will be a safety hazard and may invite downgrading of its use or even abandoning of the structure.

To summarize, an overview of structural health monitoring of laminated composites using different sensing techniques has been presented here. The suitability of PVDF and MS sensors for detecting damages in structures using time domain response of the system is demonstrated via numerical modeling. A complete non-contact sensing of structural damage in frequency domain by using Laser Doppler Scanning Vibrometer is demonstrated via experimental modal analysis. It is envisaged that by integrating all these in-contact and non-contact techniques, a complete on-line and off-line health investigation process could be developed which will lead to the use of high performance composites in advanced systems.