Ship Unloader Trolley’s Cycle Optimization

Abstract

The application described hereunder will show how to save time, energy and money using a smart strategy control in order to drive the trolley’s electrical motor in a crane environment. Very often in the ports it is necessary to unload ships standing along the docks. The load can be containers full of wares but often the ship is full of row material such as pellets (small balls made of iron and coal) that must be dropped over a moving rubber belt feeding a steel reduction device. In both cases the problem is still the same: how to reduce the swinging of containers or of the hoist and grab. It is very important to point out that by using a smart driving strategy in order to reduce the swinging time, it can be possible to minimize drastically the unloading time of a ship saving not only the dock space, but even the working time of the crane. The first aspect is important because the ship can reduce the unloading time, the second point because the duty time of the crane motors will be smaller. Just to have an idea let us consider an unloading cycle: 1 Grab up to the hold full of material 2 Trolley from ship to hopper 3 Waiting time to swinging stop 4 Grab down and unloading 5 Empty grab up 6 Trolley back to hold of the ship 7 Waiting time of swinging stop 8 Grab down to material 9 Grab loading material