Research On States Prediction And Recoverycontrol Of Civil Aircraft Emergency

Civil aircraft emergency threatens flight safety seriously. With the development of the aircrafts’ system stability, the proportion of flight emergency, which are caused by the atmospheric disturbances increases greatly. When the aircraft execute the scheduled task, how to restrict flight state in normal flight envelope is the key to ensure flight safety. Based on a certain civil aircraft modeling data, the whole flight dynamics model and linear parameter-varying model were built. In order to safely escape flight emergency, the moving horizon control was studied. Furthermore, this paper does further research on the control strategy about aircrafts’ glide slope capturing and tracking under wind shear. The main research contents are as follows:(1) The whole nonlinear kinematics and dynamics model was built. Base on a certain civil aircraft modeling data, the aerodynamic force and moment model was systematically analyzed, while the automatic flight control system was built. Furthermore, model validation was studied. The whole model has been used in the engineering application.(2) A near-ground dynamics model under wind disturbance was deduced. Furthermore, a landing gear model for abnormal touchdown procedure was established. Based on popular civil aircraft’s modeling data and flight data record(FDR), overweight landing and go around after abnormal touch down under wind disturbance were simulated.(3) The aircraft linear parameter-varying model during the glide path capture and tracking was built. Each aerodynamic coefficient was systematically analyzed and simplified by the special flight condition. Using function substitute method, the aircraft longitude 3 DOF linear parameter-varying model was built. Furthermore, the model validation was studied.(4) Based on the linear parameter-varying model of large civil aircraft, the model predictive control was studied to protect aircraft against loss-of-control during takeoff and landing. The flight envelope was quantized to state restriction. Furthermore, an on-line model predictive controller was designed. The validity of the controller is demonstrated by aircrafts’ glide slope capturing and tracking simulation.