Research On Control Method For Quadrotor Carrying A Load System Based On Saturated Method

With the increase of load-carrying UAV in reality,more and more people are aware of the advantages of this system.UAVs can perform aerial operations that many robots cannot achieve and transport objects to their destinations faster,which has prompted more people to be keen to study UAV carrying a load.In this paper,three control methods are designed for the real-time logistics application of the UAV carrying load system to meet different needs.In this article,the main works are listed as follows:Firstly,a control method based on cascade saturation is studied for the general logistics transportation problem.First,the general model of the UAV carrying a load system is established by using the Newton-Euler equations,and then the complex model is simplified into four independent subsystems.The cascaded saturation controller is designed for the above four subsystems and the stability analysis is carried out based on recursion theorem.The parameters range in the saturation controller is obtained by the Routh-Hurwitz stability criterion,and the stability of the system is proved.Theoretical and simulation analysis shows that the proposed method can effectively limit the amplitude of the load swing.Secondly,a nested saturation control method is proposed for the problem of strictly limiting the swing control in logistics transportation.First,the UAV carrying a load is modeled.The control model of UAV carrying a load is transformed into a stability control design problem for a feedforward cascade nonlinear system through designing the nested saturation control.After the nested saturation controller is designed,the swing of the load on the UAV is limited by restricting the control input of the system.Finally,a decoupled independent saturation method is compared with the control method proposed in this chapter through Matlab simulation platform.The simulation shows the effectiveness of the proposed method.Thirdly,a terminal sliding mode control method is proposed in this chapter for the problem of fast transportation load in the problem of logistics transportation in reality.The model of the UAV carrying a load system is modeled.The system is divided into inner and outer loops.Then the terminal sliding mode controller is designed for the attitude system of inner loop and the position system of outer loop respectively.The stability of the system is proved by the Lyapunov function.Finally,the traditional sliding mode control and the control method of this chapter are simulated and verified,and the effectiveness of the proposed method is highlighted by simulation.