Intelligent health monitoring of structures using smart sensors, wavelet neural networks and fuzzy logic

The purpose of this study is to investigate the compatibility of Self-Powered Sensors and Low-Power Wireless Protocol in a Structural Health Monitoring System. The other purpose of the project is to exploit the ever increasing computational capabilities of computers by transferring the processing burden away from complex hardware traditionally used in health monitoring. Thus the major focus of the project is to develop new sensing capabilities that use vibration as a way to detect structural damage as well as to power sensors and the ultra low-power data distribution system for information dissemination. The goal of the project is to reduce the use of expensive sensing, signal processing and data acquisition systems toward a simpler, energy-efficient, easily scalable, cost-efficient and intelligent prognostics health monitoring system.;Power Output tests were conducted on aircraft representative structural specimens using PZT Ceramics as primary strain measuring sensors. These sensors were integrated with sensor validation algorithms and sensor output prediction mathematical models to constantly monitor the sensor integrity in real-time. These sensors were further integrated with Diagnostic and Prognostic Neural Networks. The Diagnostic Neural Network (DNN) based on multi-resolution temporal signals monitor data from various sensors to recognize any potential structural flaw. Since the DNN is a parallel signal processing paradigm and since it is based on multi-resolution analysis, these systems can be easily adapted to real-time health monitoring. A Prognostic Neuro-Fuzzy System has also been developed in the project to predict the amount of life a structural member has endured.;Since the focus of the project from the start has been away from expensive sensing capabilities and toward intelligent algorithms working on simple processor cores, one can achieve better fault-tolerant capabilities. Also, since the core of the health monitoring is done by the micro-controllers, the number of potential points of failure is drastically reduced. Hence one does not require a monitoring system for a structural monitoring system.