Double-pendulum underactuated control for quadrotor UAV with slung load

Purpose The double pendulum phenomenon observed in quadrotor unmanned aerial vehicle (UAV) transportation is primarily attributed to the dynamics of the hook and payload. While quadrotor UAV systems inherently exhibit underactuation and instability, the addition of a hook and load for transport significantly amplifies these challenges. The double-pendulum quadrotor positioning and anti-swing control method based on online trajectory planning is proposed in this paper. Design/methodology/approach The three-dimensional quadrotor UAV dynamic model is built. A new trajectory that has the performances of positioning and anti-swing is constructed by adding an anti-swing control. The anti-swing control method without influencing positioning is introduced, which is based on the smooth S trajectory. The dynamic coupling relationship between the quadrotor and hook load is used. Findings This paper integrates online trajectory planning control with a constructed 3D double-pendulum quadrotor UAV dynamics model and provides detailed derivation and stability proof. Originality/value The proposed method in this paper can quickly eliminate hook and load swing angle and achieve accurate positioning of the quadrotor UAV, which effectively suppresses residual swing angle and improves the safety and reliability of UAV transportation.