Modeling and Anti-Swing Control for 7-DOF Overhead Crane with Double Spherical Pendulum and Varying Cable Length Effects

Complex double spherical pendulum dynamics increase the difficulty of the swing suppression control for underactuated overhead crane. Moreover, it would be a big challenge for trolley and bridge motion control while considering varying cable length effects. In this article, an accurate dynamic model for seven degree-of-freedom (7-DOF) overhead crane with double spherical pendulum and varying cable length effects is established by Lagrangian method without any simplifications. The dynamic model includes trolley travelling, bridge moving, cable length varying, hook swing and payload swing. An anti-swing controller is designed to suppress the hook swing and payload swing simultaneously. Theoretical analysis and simulation results prove the accuracy of the dynamic model and the effectiveness of the anti-swing controller.