There are 10 of Amazon's eighth-generation fulfillment centers based across the US. Central to these is the Kiva mobile fulfillment system, which Kiva says increases productivity by 2-4 times over other picking methods.
The traditional approach to warehouse picking sees individual employees moving around the warehouse to collect the required items from shelves. This can be a time-consuming process, especially if order items are scattered around the warehouse and if the warehouse itself is at all large.
The Kiva system flips this approach on its head. Pickers are assigned to static stations that are laid out for ease of use. The order being processed is shown on a screen and mobile shelves containing the items are transported to the picking station by autonomous robots. A laser points out where the item is located on the shelf, and the picker simply scans it for confirmation before grouping it with any other items in the order.
The robots themselves are low enough to the ground to be able to move beneath the mobile shelving units, from where they can pick the units off the ground slightly for transportation. They are connected to a wireless network and navigate using barcodes on the floor. Sensors on the robots help them to detect and avoid obstacles. Amazon says it has over 15,000 Kiva robots operating in the US.
In addition to the Kiva system, Amazon's eighth-generation fulfillment centers feature a Robo-Stow robotic arm for moving large quantities of inventory items, vision systems for unloading good from a trailer in half an hour, and a computer system designed for ease of use by employees.