1. A method comprising, under the control of one or more computer systems configured with executable instructions: for each inventory item of a plurality of inventory items: determining an identity of the inventory item to be grasped from among identities previously stored for inventory items; accessing, based on the determined identity of the inventory item, a record from an item database including characteristics of the inventory item; accessing, based at least in part on the characteristics of the inventory item, grasping strategies from an item grasping database; and responsive to the inventory item not having a grasping strategy associated therewith: generating a grasping strategy for the inventory item based at least in part on at least one of (i) characteristics of the inventory item that are at least one of stored in the record or detected by one or more sensors; (ii) input from a human operator received through a human-based grasping strategy module for grasping the inventory item; (iii) grasping strategies for items with characteristics similar to the characteristics of the inventory item; (iv) physical constraints associated with a location in which the inventory item is to be grasped or placed; or (v) information about a success of grasping strategies that have been previously employed; instructing a robotic manipulator to perform the generated grasping strategy for the inventory item; and storing the generated grasping strategy in association with the characteristics of the inventory item in the item grasping database.