In [2], it's very surprising that the system is designed so that the worker must use steps to access bins on the transporter. Since this seems so obviously and counterintuitively bad for the workflow I assume there must be a very, very good reason for it. Would be interesting to know what it is.
That surprised me, too, because a previous version of the system used smaller bin stacks and no steps.
Amazon could have gone in the other direction. The layout could be designed so that the picker sits on a swivel stool and never stands at all. That's what they do when they test robot picking - there's one human-sized robot arm on a turntable mount doing the picking.
