A robust anti-swing control method based on the error transformation function is proposed,and the problem is handled for the unmanned helicopter slung-load system(HSLS)deviating from the equilibrium state due to the d...A robust anti-swing control method based on the error transformation function is proposed,and the problem is handled for the unmanned helicopter slung-load system(HSLS)deviating from the equilibrium state due to the disturbances in the lifting process.First,the nonlinear model of unmanned HSLS is established.Second,the errors of swing angles are constructed by using the two ideal swing angle values and the actual swing angle values for the unmanned HSLS under flat flight,and the error transformation functions are investigated to guarantee that the errors of swing angles satisfy the prescribed performance.Third,the nonlinear disturbance observers are introduced to estimate the bounded disturbances,and the robust controllers of the unmanned HSLS,the velocity and the attitude subsystems are designed based on the prescribed performance method,the output of disturbance observer and the sliding mode backstepping strategy,respectively.Fourth,the Lyapunov function is developed to prove the stability of the closed-loop system.Finally,the simulation studies are shown to demonstrate the effectiveness of the control strategy.展开更多
基金This work was supported in part by the National Natural Science Foundation of China(No.62003163)the National Science Fund for the Key R&D projects(Social Development)in Jiangsu Province of China(No.BE2020704)+3 种基金the Aeronautical Science Foundation of China(Nos.201957052001,20200007052001)the Jiangsu Province“333”project(No.BRA2019051)the Postdoctoral Research Foundation of Jiangsu Province(No.2020Z112)the Natural Science Foundation of Jiangsu Province for Young Scholars(No.BK20200415)。
文摘A robust anti-swing control method based on the error transformation function is proposed,and the problem is handled for the unmanned helicopter slung-load system(HSLS)deviating from the equilibrium state due to the disturbances in the lifting process.First,the nonlinear model of unmanned HSLS is established.Second,the errors of swing angles are constructed by using the two ideal swing angle values and the actual swing angle values for the unmanned HSLS under flat flight,and the error transformation functions are investigated to guarantee that the errors of swing angles satisfy the prescribed performance.Third,the nonlinear disturbance observers are introduced to estimate the bounded disturbances,and the robust controllers of the unmanned HSLS,the velocity and the attitude subsystems are designed based on the prescribed performance method,the output of disturbance observer and the sliding mode backstepping strategy,respectively.Fourth,the Lyapunov function is developed to prove the stability of the closed-loop system.Finally,the simulation studies are shown to demonstrate the effectiveness of the control strategy.
