Abstract: A system for transporting inventory items includes an inventory holder capable of storing inventory items and a mobile drive unit. The mobile drive unit is capable of moving to a first point with the inventory holder at least one of coupled to and supported by the mobile drive unit. The mobile drive unit is additionally capable of determining a location of the inventory holder and calculating a difference between the location of the inventory holder and the first point. The mobile drive unit is then capable of determining whether the difference is greater than a predetermined tolerance. In response to determining that the difference is greater than the predetermined tolerance, the mobile drive unit is also capable of moving to a second point based on the location of the inventory holder, docking with the inventory holder, and moving the mobile drive unit and the inventory holder to the first point.

Abstract: A method for inventory management includes deploying a first mobile drive unit having first dimensions and deploying a second mobile drive unit having second dimensions, the first and second dimensions being different. The first and second mobile drive units are operable to transport inventory items to a plurality of inventory stations in the same workspace.

Abstract: A system includes a first mobile drive unit and a second mobile drive unit. The system also includes a first inventory holder, a second inventory holder, and a third inventory holder. An inventory station includes a first location and a second location and the inventory station operable to receive a first inventory item from the first inventory holder at the first location. The first inventory holder is transported by the first mobile drive unit. The inventory station is also operable to receive a second inventory item from the second inventory holder at the first location. The second inventory holder is transported by the second mobile drive unit. The inventory station is also operable to receive a third inventory item from the third inventory holder at the second location. The third inventory holder is fixed at the second location while the inventory station receives the first inventory item and the second inventory item.

Abstract: A method for inventory management includes deploying a first mobile drive unit having first dimensions and deploying a second mobile drive unit having second dimensions, the first and second dimensions being different. The first and second mobile drive units are operable to transport inventory items to a plurality of inventory stations in the same workspace.

Abstract: A method for moving one or more mobile drive units within a workspace includes receiving, from a first mobile drive unit, a reservation request requesting use of a first path segment to move in a first direction. The method further includes determining that a second mobile drive unit is currently located on the first path segment and determining whether the second mobile drive unit is moving in the first direction. Additionally, the method includes transmitting a reservation response indicating that the reservation request is denied, in response to determining that the second mobile drive unit is not moving in the first direction. The method also includes transmitting a reservation response indicating that the reservation request is granted, in response to determining that the second mobile drive unit is moving in the first direction.

Abstract: A system includes a first mobile drive unit and a second mobile drive unit. The system also includes a first inventory holder, a second inventory holder, and a third inventory holder. An inventory station includes a first location and a second location and the inventory station operable to receive a first inventory item from the first inventory holder at the first location. The first inventory holder transported by the first mobile drive unit. The inventory station also operable to receive a second inventory item from the second inventory holder at the first location. The second inventory holder transported by the second mobile drive unit. The inventory station also operable to receive a third inventory item from the third inventory holder at the second location. The third inventory holder is fixed at the second location while the inventory station receives the first and second inventory item.

Abstract: A system for transporting inventory items includes an inventory holder capable of storing inventory items and a mobile drive unit. The mobile drive unit is capable of moving to a first point with the inventory holder at least one of coupled to and supported by the mobile drive unit. The mobile drive unit is additionally capable of determining a location of the inventory holder and calculating a difference between the location of the inventory holder and the first point. The mobile drive unit is then capable of determining whether the difference is greater than a predetermined tolerance. In response to determining that the difference is greater than the predetermined tolerance, the mobile drive unit is also capable of moving to a second point based on the location of the inventory holder, docking with the inventory holder, and moving the mobile drive unit and the inventory holder to the first point.

Abstract: A method for fulfilling inventory requests includes receiving an inventory request requesting an inventory item and selecting the requested inventory item from an inventory holder. The method further includes storing the requested inventory item in an order holder associated with the inventory request and moving the order holder to a storage space. In addition, the method includes detecting a triggering event and in response to detecting the triggering event, retrieving the order holder from the storage space.

Abstract: A method for fulfilling orders at an inventory pier includes receiving orders. The orders are examined to identify an inventory item stored by an inventory holder stationed at an inventory pier. A first order is grouped with a second order based at least in part upon determining that the first order and the second order include requests for the inventory item. A first container associated with the first order and a second container associated with the second order are arranged on an order holder at an induction station. The first container and the second container are operable to receive the inventory item. The mobile drive unit is instructed to transport the order holder from the induction station to the inventory pier. The order holder receives the inventory item from the inventory pier at a location opposite to the inventory holder.

Abstract: A method of rotating an inventory holder includes moving an inventory holder towards a rotation area along a straight segment of a path with a first face of the inventory holder facing a first direction. The rotation area includes a portion of a workspace designated for rotation of inventory holders. The method further includes moving the inventory holder into the rotation area along a first arced segment with an orientation of the first face perpendicular to the first arced segment. The method additionally includes executing a rotation maneuver within the rotation area and moving the inventory holder out of the rotation area along a second arced segment with a second face facing the first direction.

Abstract: A method for transporting inventory items includes moving a mobile drive unit to a first point within a workspace. The first point is a location of an inventory holder. The method further includes docking the mobile drive unit with the inventory holder and moving the mobile drive unit and the inventory holder to a second point within the workspace. The second point is associated with conveyance equipment. The method further includes moving the inventory holder to a third point within the workspace using the conveyance equipment.

Abstract: A method includes determining, by a management module, to complete an inventory request, the inventory request identifying an inventory item. The method also includes identifying, by the management module, an inventory holder storing the inventory item, and identifying, by the management module, a mobile drive unit to transport the inventory holder to an inventory station.

Abstract: A method of transporting inventory items includes receiving a route request from a mobile drive unit. The route request identifies a destination location within a workspace. The workspace includes at least one cell associated with a first cell attribute and at least one cell that is not associated with the first cell attribute. The method includes determining a state of the mobile drive unit. The method also includes generating a path to the destination location for the mobile drive unit that traverses cells associated with the first cell attribute, in response to determining that the mobile drive unit is associated with a first state. The method includes generating a path to the destination location for the mobile drive unit that does not traverse cells associated with the first cell attribute, in response to determining the mobile drive unit is not associated with the first state. The method further includes transmitting the path to the mobile drive unit.

Abstract: A system for transporting inventory items includes an inventory holder capable of storing inventory items and a mobile drive unit. The mobile drive unit is capable of moving to a first point with the inventory holder at least one of coupled to and supported by the mobile drive unit. The mobile drive unit is additionally capable of determining a location of the inventory holder and calculating a difference between the location of the inventory holder and the first point. The mobile drive unit is then capable of determining whether the difference is greater than a predetermined tolerance. In response to determining that the difference is greater than the predetermined tolerance, the mobile drive unit is also capable of moving to a second point based on the location of the inventory holder, docking with the inventory holder, and moving the mobile drive unit and the inventory holder to the first point.

Abstract: A system includes a first mobile drive unit and a second mobile drive unit. The system also includes a first inventory holder, a second inventory holder, and a third inventory holder. An inventory station includes a first location and a second location and the inventory station operable to receive a first inventory item from the first inventory holder at the first location. The first inventory holder transported by the first mobile drive unit. The inventory station also operable to receive a second inventory item from the second inventory holder at the first location. The second inventory holder transported by the second mobile drive unit. The inventory station also operable to receive a third inventory item from the third inventory holder at the second location. The third inventory holder is fixed at the second location while the inventory station receives the first and second inventory item.

Abstract: A method for inventory management includes deploying a first mobile drive unit having first dimensions and deploying a second mobile drive unit having second dimensions, the first and second dimensions being different. The first and second mobile drive units are operable to transport inventory items to a plurality of inventory stations in the same workspace.

Abstract: A method for moving one or more mobile drive units within a workspace includes receiving, from a first mobile drive unit, a reservation request requesting use of a first path segment to move in a first direction. The method further includes determining that a second mobile drive unit is currently located on the first path segment and determining whether the second mobile drive unit is moving in the first direction. Additionally, the method includes transmitting a reservation response indicating that the reservation request is denied, in response to determining that the second mobile drive unit is not moving in the first direction. The method also includes transmitting a reservation response indicating that the reservation request is granted, in response to determining that the second mobile drive unit is moving in the first direction.

Abstract: A method for fulfilling inventory requests includes receiving an inventory request requesting an inventory item and selecting the requested inventory item from an inventory holder. The method further includes storing the requested inventory item in an order holder associated with the inventory request and moving the order holder to a storage space. In addition, the method includes detecting a triggering event and in response to detecting the triggering event, retrieving the order holder from the storage space.

Abstract: A method for fulfilling inventory requests includes receiving an inventory request requesting an inventory item and selecting the requested inventory item from an inventory holder. The method further includes storing the requested inventory item in an order holder associated with the inventory request and moving the order holder to a storage space. In addition, the method includes detecting a triggering event and in response to detecting the triggering event, retrieving the order holder from the storage space.

Abstract: A system for transporting inventory items includes an inventory holder capable of storing inventory items and a mobile drive unit. The mobile drive unit is capable of moving to a first point with the inventory holder at least one of coupled to and supported by the mobile drive unit. The mobile drive unit is additionally capable of determining a location of the inventory holder and calculating a difference between the location of the inventory holder and the first point. The mobile drive unit is then capable of determining whether the difference is greater than a predetermined tolerance. In response to determining that the difference is greater than the predetermined tolerance, the mobile drive unit is also capable of moving to a second point based on the location of the inventory holder, docking with the inventory holder, and moving the mobile drive unit and the inventory holder to the first point.