Nonlinear Control with Energy Shaping for Unmanned Helicopter Slung-load System Based on Disturbance Observer

In this study, a nonlinear anti-swing controller based on energy shaping and disturbance observer is designed for the longitudinal system model of unmanned helicopter slung-load under the external disturbance. A finite time sliding mode disturbance observer (FTSMDO) is employed to estimate the external disturbance, and the anti-swing controller is devised by combining with the energy shaping and Lyapunov analysis. The Lyapunov principle and LaSalle invariance theorem are used to prove the asymptotic stability of all errors in the closed-loop system, and the effectiveness of the proposed method is verified by a comparative simulation.