A Sliding Mode Tracking Control Method for Double Pendulum Crane Systems With Variable Rope Length

Crane systems are usually applied to achieve transportation for heavy payloads in many industrial fields. When the transported cargo cannot be regard as a mass point or the hook mass needs to be considered, the crane system is a double pendulum system, which will bring much more difficulty in design suitable control methods. Considering this fact, we propose a sliding mode tracking method for double pendulum cranes with variable rope length, which achieves accurate trolley and payload hoisting/lowering positioning by properly tracking the pre-planned reference trajectories. The important swing suppression for both payload’s and hook’s swing angles is also ensured simultaneously. Finally, some simulations are included to better verify our method.