A Novel Approach for Structural Health Monitoring Using In Situ Thermoelastic Stress Analysis

Abstract

The Australian Defence Science and Technology Organisation has developed a novel low-cost, rugged and compact thermoelastic stress analysis (TSA) system for non contact full-field stress analysis based on a microbolometer detector. As commercial microbolometer devices invariably reduce in size and cost, microbolometer-based TSA could have significant ramifications for aircraft structural integrity management, especially in the area of in situ structural health monitoring (SHM). An integrated full-field stress measurement capability in operational aircraft could continually monitor structural ‘hot spots’ providing both diagnostic and prognostic information to aid in efficient structural management. This paper provides an overview of the technology and outlines some of its potentially unique SHM capabilities through laboratory coupon studies and demonstrations on a full-scale fatigue test of a flight-critical aircraft structural component. These experimental studies illustrate key aspects of this capability which in turn point to possible future directions in its development and application. Although the case study focuses on an aircraft structure, the concept has potential application to a wide variety of different engineering assets across the aerospace, civil and maritime sectors.