Barrier Lyapunov function-based nonlinear cooperative control approach for dual-quadrotor slung load system

Due to the limited payload capacity of single-quadrotor unmanned aerial vehicles (UAVs) in cargo transportation, there is a pressing need for the collaborative transportation of heavy goods using multiple quadrotor UAVs. In this context, the dual-quadrotor aerial transportation system stands out for its heightened research significance, driven by its stringent requirements for controller swing reduction performance. In practical transportation scenarios, uncertainties such as disturbances and emergency avoidance constraints elevate the risk associated with excessive variations in the relative distances between quadrotor aircraft during collaborative transportation. Building upon the established nonlinear model by D'Alembert, this paper proposes a nonlinear coordinated control strategy based on the barrier Lyapunov function. The strategy employs an innovative energy storage approach, incorporating cooperative error constraints to effectively restrict relative errors between quadrotor aircraft, thereby mitigating the risk of collisions. Furthermore, this control strategy facilitates rapid convergence of the positions of quadrotor aircraft and the swing angles of suspended loads. Theoretical analyses, grounded in LaSalle's invariance theorem, provide evidence of the stability of the closed-loop system. Finally, comparative assessments conducted using the Matlab/Simulink visualization platform validate the superior control performance of the designed controller in collaborative transportation scenarios.