HUGE Lego train coal terminal fully automated by Arduino

Three Lego trains load and unload at a huge Lego coal terminal. Everything is automated by Arduino. The trains can stop at two silos to load coal into their wagons. Next, they are parked at the train yard. When the unload facility is available, a train will be unloaded. The unloading part is the most complicated part of the structure: after arrival of the Lego train, pneumatic cilinders will push a conductor to the bottom of the wagons, where also a conductor is located. These conductors drive power which