Efficient shuffling of mobile drive units for inventory holders

A method comprising:

• retrieving a new inventory holder from a storage location and temporarily placing the new inventory holder in a temporary staging location;
• moving a mobile drive unit to a first pick location at which a first inventory holder is positioned;
• repositioning, using the mobile drive unit, the first inventory holder from the first pick location to the temporary staging location proximal to the first pick location upon the first inventory holder being recently completed;
• repositioning, using the mobile drive unit, a second inventory holder from a second pick location to the first pick location vacated by the repositioning of the first inventory holder, the second pick location being located adjacent to the first pick location;
• transporting, using the mobile drive unit or another mobile drive unit, the first inventory holder away from the temporary staging location;
• and
• repositioning, using the mobile drive unit, the new inventory holder from the temporary staging location to one of the second pick location or a third pick location,
• wherein the temporary staging location and the first, second and third pick locations are part of a pick station within a warehouse.

An inventory system comprising:

• a plurality of mobile drive units that are remotely controllable to transport inventory holders about a warehouse;
• and
• a management module configured to direct movement of the plurality of mobile drive units to transport the inventory holders among regions in the warehouse, the management module being further configured to direct a mobile drive unit from the plurality of mobile drive units to perform a shuffle process within a region of the warehouse as follows:
• directing the mobile drive unit or another mobile drive unit from the plurality of mobile drive units to retrieve a new inventory holder from a storage location and temporarily placing the new inventory holder in a temporary staging location;
• directing the mobile drive unit to reposition a first inventory holder from a first pick location within the region to the temporary staging location within the region that is proximal to the first pick location upon the first inventory holder attaining a completion status;
• directing the mobile drive unit to subsequently position a second inventory holder from a second pick location into the first pick location vacated by repositioning the first inventory holder, the second pick location being adjacent to the first pick location;
• directing the mobile drive unit or another mobile drive unit from the plurality of mobile drive units to transport the first inventory holder away from the temporary staging location within the region of the warehouse;
• and
• directing the mobile drive unit or another mobile drive unit from the plurality of mobile drive units to reposition the new inventory holder from the temporary staging location to the second pick location or a third pick location,
• wherein the region of the warehouse includes a pick station.

An inventory system comprising:

• a plurality of inventory holders to store items, the plurality of inventory holders including at least first, second, and third inventory holders wherein the first inventory holder is positioned at a first pick location of a pick station, the second inventory holder is positioned at a second pick location of the pick station, and the third inventory holder is positioned at a third pick location of the pick station;
• and
• a mobile drive unit configured to shuffle the first, second, and third inventory holders as follows:
• retrieving a new inventory holder and depositing the new inventory holder in a first holding location;
• moving the first inventory holder from the first pick location to a second holding location upon the first inventory holder attaining a complete status, the second holding location being separate from the first, second, and third pick locations, the first and second holding locations being located adjacent to each other and separate from the first, second, and third pick locations;
• subsequently moving the second inventory holder from the second pick location into the first pick location vacated by the first inventory holder;
• and
• subsequently moving the third inventory holder from the third pick location into the second pick location vacated by the second inventory holder;
• and
• subsequently moving the first inventory holder away from the second holding location to remove the first inventory holder from the pick station,
• wherein the first and second holding locations are located within the pick station.