Research On Sliding Mode Observers-Based Fault Diagnose With Application To Flight Control Systems

This paper deals with the actuator fault detection, isolation and estimation problem for a class of linear systems with unknown disturbance.(1) First and foremost, this paper briefly introduces the basic concept, popular research methods of fault diagnosis in addition to its development history and future prospect.(2) Based on the relevant research of predecessors, a novel sliding mode observer-based fault diagnosis and isolation (FDI) method is proposed. To isolate the possible actuator faults, we first relate each possibility to a faulty model, then for each possible faulty model, a Sliding Mode Observer (SMO) is designed, we define the residuals as the norm of the magnitudes of the output estimation errors resulting from all possible faulty models. It is proved that, for the faulty model corresponds to the faulty actuators; the SMO designed can ensure the related output estimation error converges to a sufficient small set. It is also shown that, for all other possible faulty models, the related output estimation errors are much larger.(3) In addition, the proposed actuator FDI method is tested on a Research Civil Aircraft Model (RCAM), and the successful simulation results show that it can isolate various types of actuator faults effectively.(4) Furthermore, we build the three-dimensional models and demonstrate visualized simulation by using Visual C++ & OpenGL,MultiGen-Pradigm Creator, Skin++.(5) Finally, we summarize the major conclusions of this paper and put forward the future direction of research prospect.