This work studies the trajectory tracking control for unmanned aerial helicopter(UAH)system under both matched disturbance and mismatched ones.Initially,to tackle the strong coupling,an input-output feedback lineariza...This work studies the trajectory tracking control for unmanned aerial helicopter(UAH)system under both matched disturbance and mismatched ones.Initially,to tackle the strong coupling,an input-output feedback linearization method is utilized to simplify the nonlinear UAH system.Secondly,a set of finite-time disturbance observers(FTDOs)are proposed to estimate mismatched disturbances with their successive derivatives,which are utilized to design the feedforward controller via backstepping.Thirdly,as for matched disturbance,by defining the disturbance characterization index(DCI)to determine whether the disturbance is harmful or not for the UAH system,a feedback controller is proposed and a sufficient condition is established to ensure the convergence of the tracking error.Finally,some numerical simulations and comparisons illustrate the validity and advantages of our control scheme.展开更多
To keep multiple missiles to fly in a formation, a robust controller for missile formation is designed. Based on the leader-follower formation mode, two formation relative motion models in different coordinate frames ...To keep multiple missiles to fly in a formation, a robust controller for missile formation is designed. Based on the leader-follower formation mode, two formation relative motion models in different coordinate frames are established and compared. The three-dimension model built in a follower reference coordinate frame is chosen due to its control inputs decoupling, then this model is decoupled into three subsystems. For each subsystem a robust formation controller is proposed based on the disturbance observer and f＇mite-time control theory when the external disturbance exits. The stability of the closed-loop system adopting the controller is proved theoretically. Simulation resuits show that the follower can foUow the leader and keep the desired formation despite the external disturbance, which validates the effectiveness of the proposed robust formation controller.展开更多
基金This work was supported by National Natural Science Foundations of China(Nos.62073164,61873127,61922042)the Foundation of Equipment Pre-research Project of Key Laboratory(No.61422200306).
文摘This work studies the trajectory tracking control for unmanned aerial helicopter(UAH)system under both matched disturbance and mismatched ones.Initially,to tackle the strong coupling,an input-output feedback linearization method is utilized to simplify the nonlinear UAH system.Secondly,a set of finite-time disturbance observers(FTDOs)are proposed to estimate mismatched disturbances with their successive derivatives,which are utilized to design the feedforward controller via backstepping.Thirdly,as for matched disturbance,by defining the disturbance characterization index(DCI)to determine whether the disturbance is harmful or not for the UAH system,a feedback controller is proposed and a sufficient condition is established to ensure the convergence of the tracking error.Finally,some numerical simulations and comparisons illustrate the validity and advantages of our control scheme.
基金Supported by the National Natural Science Foundation of China(10872029)
文摘To keep multiple missiles to fly in a formation, a robust controller for missile formation is designed. Based on the leader-follower formation mode, two formation relative motion models in different coordinate frames are established and compared. The three-dimension model built in a follower reference coordinate frame is chosen due to its control inputs decoupling, then this model is decoupled into three subsystems. For each subsystem a robust formation controller is proposed based on the disturbance observer and f＇mite-time control theory when the external disturbance exits. The stability of the closed-loop system adopting the controller is proved theoretically. Simulation resuits show that the follower can foUow the leader and keep the desired formation despite the external disturbance, which validates the effectiveness of the proposed robust formation controller.
