Control System Design On Transition Stage Of Tilt Rotor UAV

In recent years,with the continuous progress and development of science and technology,unmanned aerial vehicle(UAV)market has been emerged.UAV almost solves lots of practical problems with revolutionary progress in real life.With the increasingly complexity of UAV's working environment,the vertical tilt rotor UAV,which combines the advantages of both the rotary-wing UAV with fixed-wing UAV,begins to undertake more and more flight tasks.The transition mode is the key to the missions.However,there exist these problems,the modeling and control of the transition mode of vertical tilt rotor UAV are complex.In the process of rotated transition model,in view of the pneumatic actuator and pulling force vector control,control and distribution,the weight and rotated when radial channels and transverse has the problem of strong coupling,making UAV's aero dynamic characteristics in the process of change are extremely complex,the aero dynamic interference is serious,which will reduce the dynamic stability of UAV.In order to make the UAV fly smoothly and safely,this paper focuses on the transition mode of UAV.The main research contents of this paper are as follows.First of all,according to the mission requirements,the transitional flight control of UAV is studied,then the UAV flight platform is built,the airframe movement mode is preliminarily analyzed,according to the overall structure of the system,the flight control scheme of the vertical tilt-rotor aircraft in the rotor mode,the fixed wing mode and the transitional mode are detailed analyzed.The dynamic model of vertical tilting rotor UAV is established based on the kinematic principle of six degrees of freedom of rigid body.Secondly,the key technologies of tilt-rotor aircraft are introduced.Aiming at the characteristics of vertical tilt-rotor UAV platform,the hardware control system is designed and the operation logic under different modes is elaborated.According to the attitude balance condition of the transition mode,the equilibrium state equation is obtained,and the relationship between the tilt angle and flight velocity is determined,which provides the theoretical basis for the tilt path design.Finally,for the rotor mode control system,the attitude control structure is analyzed,the effective allocation algorithm is designed,and the attitude controllers based on PID and active disturbance rejection(ADRC)are researched and designed.On this basis,the controller design of transition mode is completed.Based on the optimal tilting path,the control allocation method based on efficiency allocation is designed,and the control effects of different controllers are simulated and compared.