Abstract: An inventory system can include a workspace in which is defined different areas and different stations at which tasks can be performed. A receipt receptacle received from a shipping vehicle can be moved to a rack without separating items from the receipt vehicle. A mobile drive unit can move the rack to an area on the workspace depending on information known about the items. Items from the receipt receptacle can be removed from the receipt receptacle and placed in inventory holders for movement or storage or in other receptacles for performance of other tasks such as order processing.

Abstract: An inventory system can include a workspace in which is defined different areas and different stations at which tasks can be performed. A receipt receptacle received from a shipping vehicle can be moved to a rack without separating items from the receipt vehicle. A mobile drive unit can move the rack to an area on the workspace depending on information known about the items. Items from the receipt receptacle can be removed from the receipt receptacle and placed in inventory holders for movement or storage or in other receptacles for performance of other tasks such as order processing.

Abstract: An inventory system can include multiple floors. The system can assign operations involving inventory items to a floor based on information about the floor, other floors, the operations, and/or the inventory items. In one example, the system may assign an order to be assembled on a floor based on the floor containing items for the order. Items may be moved to the floor from other floors to complete the order. In another example, a receipt receptacle received from a shipping vehicle can be moved to a rack without separating inventory items from the receipt vehicle. A mobile drive unit can move the rack to a floor based on information known about the inventory items matching criteria about the floor.

Abstract: A brake stack comprises a stator having an annular, inner periphery section disposed substantially along a first radial plane extending normal to an axis of a wheel, and a stator side wall having a first stator contact surface, the first stator contact surface including a sloped portion which deviates away from the radial plane defined by the annular, inner periphery section. The brake stack further comprises a rotor having an annular, outer periphery section disposed substantially along a second radial plane extending normal to the axis of the wheel, and a rotor side wall having a first rotor contact surface shaped complementary to the first stator contact surface, wherein the stator and the rotor are interleaved. A brake disk may comprise a first radius of a friction surface at a first axial position and a second radius of the friction surface at a second axial position, where the first radius is different than the second radius.

Abstract: An inventory system can include multiple floors. The system can assign operations involving inventory items to a floor based on information about the floor, other floors, the operations, and/or the inventory items. In one example, the system may assign an order to be assembled on a floor based on the floor containing items for the order. Items may be moved to the floor from other floors to complete the order. In another example, a receipt receptacle received from a shipping vehicle can be moved to a rack without separating inventory items from the receipt vehicle. A mobile drive unit can move the rack to a floor based on information known about the inventory items matching criteria about the floor.

Abstract: An inventory system can include multiple floors. The system can assign operations involving inventory items to a floor based on information about the floor, other floors, the operations, and/or the inventory items. In one example, the system may assign an order to be assembled on a floor based on the floor containing items for the order. Items may be moved to the floor from other floors to complete the order. In another example, a receipt receptacle received from a shipping vehicle can be moved to a rack without separating inventory items from the receipt vehicle. A mobile drive unit can move the rack to a floor based on information known about the inventory items matching criteria about the floor.

Abstract: Inventory holders in an inventory system can be moved among differing storage positions. The moves can be performed by mobile drive units not otherwise transporting inventory holders directly to or from inventory stations. A free mobile drive unit can move an inventory holder not likely to be useful soon at any nearby station from a storage position near the station to a position farther away from the station. A mobile drive unit can move an inventory holder likely to be useful soon from a storage position farther away from one or more stations to a storage position nearby one or more stations.

Abstract: Inventory holders in an inventory system can be moved among differing storage positions. The moves can be performed by mobile drive units not otherwise transporting inventory holders directly to or from inventory stations. A free mobile drive unit can move an inventory holder not likely to be useful soon at any nearby station from a storage position near the station to a position farther away from the station. A mobile drive unit can move an inventory holder likely to be useful soon from a storage position farther away from one or more stations to a storage position nearby one or more stations.

Abstract: An inventory system includes inventory holders, container holders, containers carried by the container holders, mobile drive units, stations, and a management module. The management module instructs the mobile drive units to move the inventory holders and container holders to stations. Container holders are loaded with containers of inbound inventory items at a first station. Inbound inventory items are transferred from containers to inventory holders at a second station. Outbound inventory items are transferred from inventory holders to containers at a third station. Containers of outbound inventory items are removed from container holders at a fourth station.

Abstract: An inventory system can receive a receipt receptacle from a shipping vehicle. The receipt receptacle can be moved to a case shuttle without separating or sorting inventory items in the receipt receptacle. A mobile drive unit can move the case shuttle to a receiving station, where the receipt receptacle can be removed and where the inventory items can be stowed in a pickable inventory holder. A mobile drive unit can move the pickable inventory holder to an order-compiling station, where inventory items can be picked from the inventory holder into order receptacles. A mobile drive unit can move an order shuttle carrying order receptacles with completed orders to a shipping station, where the completed order receptacles can be transferred to a shipping vehicle.

Abstract: Inventory holders in an inventory system can be moved among differing storage positions. The moves can be performed by mobile drive units not otherwise transporting inventory holders directly to or from inventory stations. A free mobile drive unit can move an inventory holder not likely to be useful soon at any nearby station from a storage position near the station to a position farther away from the station. A mobile drive unit can move an inventory holder likely to be useful soon from a storage position farther away from one or more stations to a storage position nearby one or more stations.

Abstract: An inventory system includes inventory holders, container holders, containers carried by the container holders, mobile drive units, stations, and a management module. The management module instructs the mobile drive units to move the inventory holders and container holders to stations. Container holders are loaded with containers of inbound inventory items at a first station. Inbound inventory items are transferred from containers to inventory holders at a second station. Outbound inventory items are transferred from inventory holders to containers at a third station. Containers of outbound inventory items are removed from container holders at a fourth station.

Abstract: An inventory system can receive a receipt receptacle from a shipping vehicle. The receipt receptacle can be moved to a case shuttle without separating or sorting inventory items in the receipt receptacle. A mobile drive unit can move the case shuttle to a receiving station, where the receipt receptacle can be removed and where the inventory items can be stowed in a pickable inventory holder. A mobile drive unit can move the pickable inventory holder to an order-compiling station, where inventory items can be picked from the inventory holder into order receptacles. A mobile drive unit can move an order shuttle carrying order receptacles with completed orders to a shipping station, where the completed order receptacles can be transferred to a shipping vehicle.

Abstract: An inventory system can include multiple floors. The system can assign operations involving inventory items to a floor based on information about the floor, other floors, the operations, and/or the inventory items. In one example, the system may assign an order to be assembled on a floor based on the floor containing items for the order. Items may be moved to the floor from other floors to complete the order. In another example, a receipt receptacle received from a shipping vehicle can be moved to a rack without separating inventory items from the receipt vehicle. A mobile drive unit can move the rack to a floor based on information known about the inventory items matching criteria about the floor.

Abstract: A brake stack comprises a stator having an annular, inner periphery section disposed substantially along a first radial plane extending normal to an axis of a wheel, and a stator side wall having a first stator contact surface, the first stator contact surface including a sloped portion which deviates away from the radial plane defined by the annular, inner periphery section. The brake stack further comprises a rotor having an annular, outer periphery section disposed substantially along a second radial plane extending normal to the axis of the wheel, and a rotor side wall having a first rotor contact surface shaped complementary to the first stator contact surface, wherein the stator and the rotor are interleaved. A brake disk may comprise a first radius of a friction surface at a first axial position and a second radius of the friction surface at a second axial position, where the first radius is different than the second radius.