An enhanced coupling optimal trajectory planning for bridge cranes

For the bridge crane system, the control objective is to deliver the cargo to the target location quickly, accurately, and with the smallest possible swing. Therefore, this paper proposes a novel signal-based trajectory planning approach and designs the corresponding tracking control strategy. The approach ensures that the payload can be transported smoothly in the shortest time and effectively suppresses and eliminates payload swing throughout the process. Specifically, a novel signal with enhanced coupling is first constructed, and then the system model is transformed into the system represented by the signal. The system is further discretized into critical control points, the trajectories are designed, and the optimization problem is formulated using the constraints obtained from the discrete system. Moreover, the proposed method enhances the coupling between the trolley motion and the payload swing angle, which reduces computational accuracy loss and improves the transient performance of the system. Additionally, a tracking controller is designed to verify the feasibility of the trajectory and enhance the tracking effect of the trajectory. Finally, the effective control performance of the proposed method is verified by comparing it with existing methods.