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AGENCY USE ONLY (Leave blank)2. REPORT DATE
FEB 023. RE.
AFRL-SR-BL-TR-02-
HEALTH MONITORING ON VIBRATION SIGNATURES
AUTHOR(S)PROFESSOR GARY YEN
PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)OKLAHOMA STATE UNIVERSITY SCHOOL OF ELECTRICAL AND COMPUTER ENGINEERING 202 ENGINEERING SOUTH STILLWATER, OK 74078-5032
SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)AIR
ABSTRACT (Maximum 200 words)This final report covers the entire contracting effort from August 1, 1997 to July 31, 2001 (with an extended year at no cost tc the program). The progress made is primarily targeted to establish the fundamental bases from analytical and simulation studies. In addition, we have moved forward to validate the algorithms developed in several experimental testbeds. Toconsolidate the technical efforts dedicated to the theoretical developments appropriate for vibration monitoring in Air Force structures (e.g., aircraft, rotorcraft and RLVs), a comprehensive "modular" approach is taken. The tasks as outlined include Wavelet feature extraction, sensor validation, feature selection, fault detection, identification and classification, knowledge representation, multi-model on-line control autonomy, nonlinear system identification, adaptive critic fault tolerant control anc multi objective optimization design. The approach is evolving as more mathematical analyses are accomplished and desired specifications are defined. The methodology proposed is generic and applicable to a wide variety of industrial applications (e.g., chemical fluidized processes, semiconductor RIE facility), medical-assisted monitoring (e.g., EKG, intra-cranial pressure monitoring) and environmental assessment (e.g., frog/bird call monitoring). The vibration data set used for preliminary test is derived from U.S. Navy CH-46E Chinook helicopters available in public domain; commonly know as the Westland data set. The data set (4-second time series) is available in public domain and has been used for benchmark comparison by researchers within this community. The data set is clean and complete as opposed to the USAF Academy bearing data set, which is highly noisy and sparse. 1. OBJECTIVE This DoD-EPSCoR research proposed to develop, design and evaluate an on-board intelligent health assessment tool for Air Force vibration monitoring applications. The system developed is capable of promptly detecting, correctly identifying, properly accommodating and reliably predicting the gradual material degradation and catastrophic component failures of Air Force vibrating structures in adverse operating environments. In addition, the system is equipped with the ability to...