Patent ID: 8275665

Claim:
A method for monitoring a storage unit, the method comprising: responsive to a computer detecting an initial presence of an item in the storage unit, collecting, by the computer, an item identification of the item, a product type of the item, and an initial mass of the item; and searching, by the computer, a database for a recorded item containing the item identification; retrieving, by the computer, a total mass of the recorded item from the database; comparing, by the computer, the initial mass of the item with the total mass of the recorded item; and responsive to a difference between the initial mass of the item and the total mass of the recorded item that is less than a predetermined amount, setting, by the computer, a tare mass of the item equal to a tare mass of the recorded item retrieved from the database; responsive to the computer detecting the item has been removed and replaced in the storage unit, collecting, by the computer, a current mass of the item; and determining, by the computer, a mass depletion of the item as the current mass of the item minus the tare mass of the item; and responsive to the mass depletion of the item reaching a threshold depletion, the computer alerting a user.