RUSKIN - Barbi Evans wears a Christmas reindeer-antler headband, her hands moving fast as she sorts toys inside a large yellow bin.
While you're sitting cozy at home, scrolling Amazon for your next holiday gift, Evans is at work finding spots for toys, trinkets and electronics that haven't even been ordered yet inside Amazon's million-square-foot warehouse in Ruskin.
"I feel like I'm Santa's helper," said Evans, 61 of Riverview, as she scans a mini Batman action figure.
With just more than a week before Christmas, Tampa Bay's four-story Amazon fulfillment center is buzzing and loud. About 2,000 people share night and day shifts as they do their part to fill several million orders Amazon expects to deliver over the holiday season just from Ruskin, one of the company's 75 distribution centers in North America.
For a sense of scale: Amazon shipped 180 million items overall during the five-day period from Black Friday to Cyber Monday this year alone.
It's all coordinated by a network of man and machine, each parcel tracked the moment a shopper hits "buy."
"Everything has a place here," said Amazon spokeswoman Kayla Hansen during a tour of the Ruskin center, which spans the area of 28 football fields.
And a fleet of autonomous robots is at the core of the speedy delivery system.
When items come into the center, workers like Evans scan each one, then push them into cubby holes inside one of thousands of portable shelving "pods" Amazon uses to house its millions of parcels of merchandise. When the yellow pod is full, a floor robot - think an orange super-sized Roomba vacuum - slides under the shelves, taking it to its designated spot on the floor.
The robots move constantly, swapping one shelf in and another out. When a shopper orders that Batman Evans placed in hole "3A," a robot takes the unit to another employee, a "picker," who puts it in a bin to be sent off and boxed.
"People are surprised to learn we have a random stow system," Evans said. "It's not like a grocery store where all the pasta, or all the produce, is kept together. It allows our employees to stow much faster."
It's Amazon's complex computer system that knows the place of each item an employee has stashed. The robots read scannable "QR" codes pasted to the floor, helping direct their movement. Sensors on the machines help them avoid any stray items that may have fallen.
When a shopper orders anything - from a toothbrush to a Kindle - Amazon's computers calculate which stowed item is closest, which can get moved to a truck or plane quickest. They then push that one to the front of the queue.
For a Tampa shopper, that could very well mean their order is coming from Ruskin or the company's other fulfillment center in Lakeland, which handles items heavier than the Ruskin center's 25-pound weight limit.
"Or it could come from Chicago," said Hansen. "It just depends."
That calculated ordering is how Amazon gets product out so fast, often in two days like it promises its Prime members who pay a $119 membership fee per year. Other retailers have followed suit, offering free shipping and two-day shipping to keep up.
Walmart just announced it has expanded its list of gifts that can be ordered on Dec. 22 and still arrive by Christmas Eve, as well as items that can be ordered up until Dec. 23 and picked up the next day at a store.
At the Ruskin center, long conveyor belts whiz overhead. Bins of orders are sent to packers, who follow the guide of the computer tracking system. It tells them which size box to select for each item while another machine spits out pre-measured packing tape.
A red light flashes as each box is scanned, a computer logging barcodes so it knows which customer shipping label to stamp on top. The boxes are sent off on a final set of belts, before they're dropped on a massive slide to make their way to the truck-loading docks.
"I'm a shopper, too," said Hansen. "And you don't really think what that box goes through before it winds up on your doorstep."
Then you go back online, and the cycle continues.
Contact Sara DiNatale at [email protected] or . Follow @sara_dinatale.