New York (CNN Business) Walmart wants store workers to help out customers instead of mopping up floors and unloading boxes in backrooms. So it's increasingly turning to robots to fill those tasks.

The world's largest retailer announced Tuesday that it is adding thousands of new robots to its stores. By next February, it expects to have autonomous floor scrubbers in 1,860 of its more than 4,700 US stores. Walmart will also have robots that scan shelf inventory at 350 stores. And there will be bots at 1,700 stores that automatically scan boxes as they come off delivery trucks and sort them by department onto conveyer belts.

Walmart says these "smart assistants" will reduce the amount of time workers spend on "repeatable, predictable and manual" tasks in stores and allow them to switch to selling merchandise to shoppers and other customer service roles.

"The overall trend we're seeing is that automating certain tasks gives associates more time to do work they find fulfilling and to interact with our customers," CEO Doug McMillon said last year of the new technology in stores.

Walmart will deploy 920-pound autonomous floor scrubbers in 1,860 of its stores by next year.

The retailer believes that bringing on bots will lift sales and make stores more efficient. Walmart also says bots limit worker turnover. That's because it's hard to consistently find workers to unload trucks and keep up stores overnight.