Nondestructive Damage Evaluation Benefits
Nondestructive damage evaluation (NDE) is a group of analysis techniques that evaluate the properties of a material, structure, or component without causing damage. It has the potential to provide critical information regarding the integrity of a structure or mechanical component throughout its life cycle. Costly structural or asset failure can also be avoided by detecting structural deterioration early with the use of NDE. At a high level, changes in the physical properties of the structure, like mass, damping and stiffness, alter the response characteristics, such as acceleration, displacement and strain. NDE systems can interpret this information and evaluate the current state of the structure. Considerable amount of work has been done in the field of NDE over the past few decades. However, most the work performed is either not applicable in practice for continuously monitoring the integrity of structures or is not designed to provide reliable information regarding the current status of the structure and/or component under investigation.
Technology available today
An important issue that delays the realization of more prominent damage evaluation algorithms is the lack of a fundamental theory for the basis of damage detection. For example, a comparison of the measured response parameters without the use of a theory that relates structural response to the location and the amount of damage.
Another important limitation has been the number of available sensors to measure vibration information. Typically for NDE, structural response is measured through a limited number of sensors, and interpolation is used to simulate additional measurement locations. This practice leads to biased damage indices, since true local information may be lost.
Fiber Optic Sensing for Nondestructive Evaluation
We partnered with Ensyso to develop a fully automated continuous health monitoring tool which enables local damage detection through the use of global vibration information. A system integration test was performed as the first step to achieve a complete NDE system. Our advanced FOS platform obtained spatially continuous strain data along the length of approximately 10 meters of fiber. Using the data provided by the sensor, Ensyso’s analysis software was able to detect the location and severity of the damage to the material. For more information about the NDE system and initial results, download the case study below.