The present application is directed to a robotic system for maintaining product inventory and dispensing products upon request from a customer or other user. Product items are stored in an inventory storage unit (ISU), one item per bin. Controller logic allows items to be stored in, and retrieved from, arbitrarily-assigned storage locations. The bins hang on rails within drawers. Upon a request from a consumer (or other user) in a fulfillment operation, the robot retrieves a bin holding the first item from the ISU. Upon a request from an operator in a replenishment operation, the robot transfers an empty bin to an operator station (such as a replenishing unit). Upon a request from an operator in a purge operation, the robot transfers bins containing the affected items to the operator station. The controller logic further allows certain operations to be prioritized and performed for the replenishment and purge operations.

The present disclosure relates to an automated storage and retrieval system. The system comprises a multi-floor storage structure defined with a storage space in each floor of the multi-floor storage structure. The system includes a plurality of storage bins arranged in the storage space and is configured to store inventory. Further, there is at least one autonomous vehicle configured to move under and transport the at least one storage bin of the plurality of storage bins and is configured to transport the plurality of storage bins within each floor and across multiple floors of the multi-floor storage structure.