Research On Modeling Technology And Control System Of Tail-Sitter Aircraft

The traditional fixed-wing UAV is limited by the take-off and landing facilities.The rotor drone has a short battery life.The tail-sitter drone combines the advantages of both.It can perform both vertical take-off and landing,and can have horizontal cruising ability.The tail-sitter drone has received extensive attention at home and abroad,and has high research value in both military and civilian fields.The tail-sitter aircraft has three typical flight states during flight: vertical flight state,transitional flight state,and horizontal cruise flight state.In this paper,the research on mathematical model construction and controller design of tail-sitter aircraft under different flight conditions is carried out.Since the difficulty of tail-sitter aircraft control lies in the special flight mode and transition process,the horizontal cruise mode is the same as that of fixed-wing aircraft.Therefore,this paper mainly studies the first two flight modes.Firstly,the configuration and principle of the tail-seat aircraft are analyzed,and the mathematical model of the tail-sitter aircraft based on the vertical Euler angle and the horizontal Euler angle is established,which avoids the singularity of the horizontal Euler angle in the vertical flight mode.The mathematical model in the vertical flight mode is decoupled and simplified,and the height and attitude PID controller is designed and verified by simulation.Secondly,an LPV model with the flight path angle as the scheduling parameter is established for the transitional flight state of the tail-seat aircraft.Using the gain scheduling method,a set of working points is selected as the gain scheduling switching working point in the transition process.At each working point,the local controller is designed by using the LQR and the hybrid sensitivity method respectively,and these local working points are tracked.The angle is used as the scheduling parameter to establish the gain scheduling controller and simulate the flat and vertical transition to verify the performance of the controller.Finally,for the traditional gain scheduling controller design method,the work point selection is conservative,and the system cannot be guaranteed to be globally stable.The controller design requires a lot of experimental verification.Based on the guardian mapping theory,the H? speed is designed.And the track angle tracking controller,and the simulation based on the guardian mapping theory design,the results show that the designed controller has a good control effect in the whole state of the transition process.Compared with the traditional gain scheduling method,the controller design based on the guardian mapping theory can ensure the global stability of the transition process,and can automatically obtain the controller parameters and scheduling range,reducing the workload.