A model-based fault injection system for aerocraft wing structure

Fault injection technologies, which are important component of prognostic and health management (PHM) system and being paid more and more attention, have been applied to estimate the health status of aerocraft, with aiming to enhance the safety and reduce the maintenance costs. This paper presents a method that can inject faults such as joint failures and skin damages into a finite element model of wing structure for overcoming the difficulty in simulating an actual structural fault. The fault modes of wing structure are analyzed and its influence can be reflected in the finite element (FE) model by controlling the command stream. The parameters such as linear displacement, angular displacement, constraint force and maximal node stress can be used to identify the corresponding fault mode. A Fault injection system, the integration of the fault injection controller compiled by Visual C++ with the finite element analysis (FEA) software ANSYS, is established. User can set parameters including fault mode, location and extent on the interactive interface of the software. With the command stream generated by fault injection controller, the FE model in normal or abnormal condition can be set up for simulating. The results for representative cases show that the outputs from the FEA software coincide with those analyzed through the theory of structural mechanics.