Efficient Generation of Fast Trajectories for Gantry Cranes with Constraints

Abstract Time is a crucial factor in the transport business. Besides the duration of the transport itself, also the loading and unloading of the goods is expected to be done as fast as possible to save valuable time and money. Amongst others, this holds true for container ships where the containers are usually loaded and unloaded by means of ship-to-shore gantry cranes. This scenario exemplarily motivates the investigations in this paper. Different methods are proposed for generating a trajectory for the load based on a geometric path connecting the loading and unloading position. As the path is usually just known right before the task has to begin, special emphasis lies on a fast calculation of the trajectory. The overall goal is to traverse the geometric path as fast as possible under the consideration of constraints for the gantry crane system. The optimal solution is calculated and serves as a reference for comparison reasons as the required computing time is usually rather large. Therefore, tailored methods for a fast calculation of the trajectory are developed. All the different approaches are evaluated and compared by means of representative test paths.

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