The warehouse that walks

In an older warehouse, a worker walks to the shelf. In a newer one, the shelf walks to the worker. Small robots lift an entire storage unit and carry it to a person who stands still and picks items from it.

The gain is enormous and it is not mainly about robot speed. Walking was the largest component of the old job: studies found pickers spending more than half their time in transit between shelves. Removing the walking removes most of the time, and it does so without the robots needing to be clever, because carrying a shelf in a straight line is a far simpler problem than finding a particular item on it.

The arrangement has a second consequence that is easy to miss. The shelves no longer need to be in any human-readable order. Items can be stored wherever there is space, with the system remembering locations, which means popular items drift towards the front through ordinary use. A warehouse organised this way looks chaotic and is substantially more efficient than one organised alphabetically.

The cost is borne by the person who stays still. The job becomes repetitive in a way that walking jobs are not, with the pace set by the arrival of shelves rather than by the worker, and several studies report higher rates of strain injury.

The technology removed the walking, which was the tiring part, and removed the variation, which was the tolerable part. Both came from the same change.