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Robust Fault Detection Using Robust Z1 Estimation and Fuzzy LogicThis research considers the application of robust Z(sub 1), estimation in conjunction with fuzzy logic to robust fault detection for an aircraft fight control system. It begins with the development of robust Z(sub 1) estimators based on multiplier theory and then develops a fixed threshold approach to fault detection (FD). It then considers the use of fuzzy logic for robust residual evaluation and FD. Due to modeling errors and unmeasurable disturbances, it is difficult to distinguish between the effects of an actual fault and those caused by uncertainty and disturbance. Hence, it is the aim of a robust FD system to be sensitive to faults while remaining insensitive to uncertainty and disturbances. While fixed thresholds only allow a decision on whether a fault has or has not occurred, it is more valuable to have the residual evaluation lead to a conclusion related to the degree of, or probability of, a fault. Fuzzy logic is a viable means of determining the degree of a fault and allows the introduction of human observations that may not be incorporated in the rigorous threshold theory. Hence, fuzzy logic can provide a more reliable and informative fault detection process. Using an aircraft flight control system, the results of FD using robust Z(sub 1) estimation with a fixed threshold are demonstrated. FD that combines robust Z(sub 1) estimation and fuzzy logic is also demonstrated. It is seen that combining the robust estimator with fuzzy logic proves to be advantageous in increasing the sensitivity to smaller faults while remaining insensitive to uncertainty and disturbances.
Document ID
20020018894
Document Type
Conference Paper
Authors
Curry, Tramone (Florida Agricultural and Mechanical Univ. Tallahassee, FL United States)
Collins, Emmanuel G., Jr. (Florida Agricultural and Mechanical Univ. Tallahassee, FL United States)
Selekwa, Majura (Florida Agricultural and Mechanical Univ. Tallahassee, FL United States)
Guo, Ten-Huei
Date Acquired
August 20, 2013
Publication Date
November 1, 2001
Publication Information
Publication: HBCUs/OMUs Research Conference Agenda and Abstracts
Subject Category
Quality Assurance and Reliability
Report/Patent Number
P13
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle20020018881Analytic PrimaryHBCUs/OMUs Research Conference Agenda and Abstracts