Planar Dynamics of Dual-quadrotors Cooperative Carrying a Slender Beam

This paper focuses on the dynamics and control of the current trendy dual-quadrotors cooperative suspension transportation system. In this article, a planar non-linear dynamic model of a dual-quadrotors suspension slender beam system is established. The coupling effects between quadrotors attitudes, cable swings and load slope are considered in the model. Subsequently, a near-hovering hypothesis is made for the nonlinear model, and a cascade control method is designed to suppress the oscillations caused by external disturbance and the oscillations generated during flight. Finally, a non-zero initial condition response and the flight command drive response are performed for a symmetrical situation, which prove that the control method successfully suppressed the vibration of the quadrotor attitude and load swing. The theoretical findings in this paper may be extended to other types of aerial cranes, such as helicopters or tilt-rotor aircraft with suspended loads.