There are two key processes in assuring the structural integrity of airframes: prediction of fatigue performance of critical components in order to specify service life and maintenance periods; and regular inspection of the airframe during scheduled maintenance. Predictions of fatigue performance need to be validated using measurement data from ground tests which also involves pausing tests and conducting inspections to evaluate the condition of the test structure and correlate with predictions. The talk will report on the results of a series of EU research programmes that have created a novel approach to inspection during ground tests on aerospace structures which is based on continuous condition monitoring and allows tests to run 24/7 resulting considerable cost savings and accelerating the design process. A low-cost, low-volume, low-mass, non-contact sensor system has been designed, developed and deployed in fatigue tests on aircraft wings. The system supplies near real-time information on changes in stress and shape over time for a region or interest (ROI) or multiple ROIs. Experiments have demonstrated a resolution of 1 mm crack propagation in metals which is considerable better than manual inspections. Current work is considering integration of the new technology with digital twins, initially for ground tests, but ultimately for aircraft in service with real-time exchange of data between the physical and virtual entities and the likely influence on design and test strategies.
About the speaker:
Eann Patterson is the AA Griffith Chair of Structural Materials and Mechanics and the Dean of the School of Engineering at the University of Liverpool. He is a Fellow of the Royal Academy of Engineering. Previously, he was Royal Society Wolfson Research Merit Awardee (2011-16), Department Chair of Mechanical Engineering at Michigan State University (2004-09) and Head of Department of Mechanical Engineering at the University of Sheffield (2000-04). He was editor-in-chief of Fatigue and Fracture in Engineering Materials and Structures (2001-06) and Journal of Strain Analysis (2006-16).