Here are the uprights, and they are made in the same way as the decks. They could have been three-sided as they share an edge with each deck, but sometimes it is easier to use modular construction techniques even should it add extra weight.
The majority of the drones currently in production are not built by robots but human beings, for a number of reasons. Humans are cheaper to employ, faster to set up in manufacture and able to run away should bombs rain down upon their factory. And if you're a dictator, they're also easier to replace.
The first means of industrial mass production anywhere in the world took place in the UK ~ naturellement Rodney ~ and involved rigging-blocks for the largest naval force in the world. There is a picture of one below, and again they'd be made from wood and produced by hand.
So in a funny way, what goes around comes around.
