Interaction of Lamb waves and sensors in structural health monitoring of carbon fiber composite

Carbon fiber composites have gained widespread popularity as advanced composite materials, finding their widespread applications across industries like aerospace, automobile, transportation, and health care. This popularity stems from their unique mechanical, electrical, and thermal properties. However, it is imperative to acknowledge that the structural integrity of these composites can undergo deterioration over time, mainly due to factors such as fatigue, impact damage, and aging. Hence, there is a burning need for a reliable method to monitor the health of these carbon fiber composite structures to prevent potential failure. The main goal of this research is to investigate the specific measurement issues when implementing a structural health monitoring approach for these composite plates by employing the guided Lamb wave technique. It is well known that the orientation of the fiber within a layered carbon fiber composite plate affects the propagation characteristics of Lamb waves. On the other hand, the sensors on and potentially embedded in the plates also interact with the Lamb wave in a dynamic manner. Using a micro-3D Laser doppler vibrometer, this research explores the microscopic interaction among the sensors, local fiber orientation and texture, and Lamb waves in these carbon fiber composite plates. Such insight can potentially lead us to a more viable means of interpreting the output of sensors and guided Lamb waves to detect defects within these composites.