Patent ID: 7693757

Claim:
A processor-implemented method for performing inventory of products with identifiers disposed on a plurality of shelves in a store, using a mobile inventory robot, the method comprising: emitting ultrasonic signals from the mobile inventory robot; detecting a returned ultrasonic signal reflected from obstacles in the store; navigating the mobile inventory robot through aisles in the store and avoiding obstacles based on the detected ultrasonic signals wherein the mobile inventory robot arrives at a shelf in the store; wherein navigating the mobile inventory robot through the store comprises locating at least one of a plurality of retro-reflective tracking tags, and wherein the retro-reflective tracking tags are secured to a fixed structure of the store to assist the mobile inventory robot in determining a location of the mobile inventory robot within the store; capturing an image of the shelf; decoding a product barcode from the captured shelf image; segmenting the captured shelf image to detect an image of at least one of the products on the shelves; retrieving a product visual descriptor from the decoded product barcode; determining whether the detected image of the at least one of the products matches the retrieved product visual descriptor; and upon determination that the detected image of the at least one of the products does not match the retrieved product visual descriptor, setting an out-of-stock flag for the product corresponding to the decoded product identifier; determining whether the at least one of the products corresponds to the decoded product barcode; and generating a flag when the at least one of the products on the shelf is located in a wrong location if the at least one of the products does not correspond to the decoded product barcode for the shelf.