Research On Control Algorithm For Uncertain Quadrotor UAV's Predetermined Performanc

QUAV is widely used in the development of today’s society.It has small size,it is easy to operate and has a lot of space for daily travel,production and military applications,deeply concerned by photographers and technicians.With the continuous development of control technology and the complexity of flight tasks,higher control requirements are required for the QUAV system,which also brings challenges to the stability control of QUAV.Due to its advantages such as fast convergence speed and good transient performance,the prescribed performance control of quadrotor UAV has become popular in current research.Based on the existed research results,this paper studies the appointed time prescribed performance control of the QUAV system based on the dynamic surface control method and the adaptive control method.The main research work is summarized as followsFirstly,according to the flight characteristics of the QUAV,a complete mathematical model of the QUAV is established by using Newton-Euler method,and appropriately explain the relevant theories of prescribed performance control.Secondly,the QUAV system with time-varying payloads and unknown dynamics parameters is studied.For position and attitude systems,adaptive prescribed performance dynamic surface control and robust adaptive control methods are designed respectively.The adaptive parameter correction method was used to estimate the load in the position loop.Combined with the dynamic surface control method,the adaptive prescribed performance position tracking controller is designed.A robust controller design method is proposed for attitude loop.Using Lyapunov stability theory,the uniform ultimate bounded stability of the tracking error of the double-closed loop system is proved.Simulation results show the effectiveness of the proposed method.Then,considering the external disturbance and unknown dynamic parameters of the QUAV system,a double closed-loops adaptive prescribed performance control design method is proposed.The adaptive control method is used to estimate the dynamic parameters and the boundary of the external disturbance on.Based on the dynamic surface technology and the backstepping method,the prescribed performance control of the position and attitude loops of the QUAV is realized.Lyapunov theory is used to prove the stability of the closed-loop system of the QUAV,and the simulation results verify the effectiveness and superiority of the proposed control method.Finally,for a QUAV system with actuator faults,the fault-tolerant control problem of a QUAV system with unknown external disturbance and unknown system parameters is studied.For the position loop and attitude loop,a new appointed time prescribed performance control strategy based on adaptive dynamic surface control framework was proposed,which realized the appointed time convergence of position and attitude tracking errors and met the requirements of prescribed transient performance.The introduction of adaptive technology in the design removes the limitation of known parameters.Finally,the stability of the closed-loop system is proved by Lyapunov theory,and the effectiveness and superiority of the proposed control scheme are verified by numerical simulation.