Identification and Monitoring of Modal Parameters in Aircraft Structures Using the Natural Excitation Technique (NExT) Combined with the Eigensystem Realization Algorithm (ERA)
Publication: Journal of Aerospace Engineering
Volume 23, Issue 2
Abstract
The early detection of cracks, fatigue, corrosion, and structural failure in aging aircraft is one of the major challenges in the aircraft industry. Common inspection techniques are time consuming and hence can have strong economic implications due to aircraft downtime. As a result, during the past decade a number of methodologies have been proposed for detecting structural damage based on variations in the structure’s dynamic characteristics. This paper describes the implementation of the natural excitation technique (NExT) combined with the eigensystem realization algorithm (ERA) to determine the dynamic characteristics of a T-34A Mentor acrobatic category aircraft and a modified DC-3 cargo/transport category aircraft. In-flight acceleration data were processed using NExT-ERA to monitor the predominant natural frequencies and associated mode shapes of the aircraft for varying flight conditions. The results show the effectiveness of this modal identification methodology and the possibility of implementing it in a real-time structural health monitoring system for aircraft.
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Acknowledgments
The writers wish to acknowledge the cooperation of Centro de Investigación en Tecnologías Aeronáuticas CITA at Colombian Air Force, Cali, Colombia.
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Information & Authors
Information
Published In
Journal of Aerospace Engineering
Volume 23 • Issue 2 • April 2010
Pages: 99 - 104
Copyright
© 2010 ASCE.
History
Received: Aug 28, 2008
Accepted: Feb 10, 2009
Published online: Apr 2, 2009
Published in print: Apr 2010
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