Fault Diagnosis For Flight Control Systems Of Quadrotor Helicopter

The safety and reliability are required for quadrotor helicopter due to its complex aerodynamic characteristics and special flight status. The quadrotor helicopter suffers from external disturbances, actuator faults, and sensor faults during flight. Thus, a more accurate mathematical model and a more robust fault diagnosis method are necessary to ensure flight quality and safety. In this paper, the attitude control model of quadrotor helicopter is studied. The possible faults are analyzed in consideration with the occurring channel of uncertainties. The incipient faults are studied specially. The faults of quadrotor helicopter can be estimated and tracked using the designed detection algorithm. The simulation results of quadrotor helicopter attitude systems validate the efficiency of the proposed detection algorithm.Firstly, the concept and classification of the fault are introduced. Then the research status and development trend of the fault diagnosis technology are given, which expound the significance of the research. Then the quadrotor dynamics model with the state equations of the attitude control systems is built under the analysis of physical effects. Finally, the semi-physical simulation platform--QstudioRP platform with hardware and software is introduced, which offers the simulation model for the research of fault diagnosis of quadrotor helicopter flight control systems.Secondly, three fault diagnosis methods for the quadrotor helicopter flight control systems are proposed based on the modeling strategy in this paper. First of all, the fault detection algorithm is put forward based on a sliding mode observer in which the uncertainties occur both in the input and the output channel. Then, the incipient fault diagnosis algorithm is proposed based on the system decoupling and associated adaptive and sliding-mode observers for the linear quadrotor model subject to incipient faults and external disturbances. Besides, the adaptive observer and sliding-mode observer are combined innovatively. Last but not least, a new associated adaptive and sliding-mode observer is proposed for the nonlinear quadrotor model under incipient faults and external disturbances.Finally, three kinds of fault diagnosis methods for the quadrotor helicopter flight control systems are applied to the QstudioRP simulation platform. The experimental results show that the three methods of fault diagnosis can effectively estimate the conventional and incipient faults of the quadrotor helicopter, which verify the feasibility and effectiveness of the proposed algorithms.