Abstract: An item may be outfitted with a cartridge for varying a net density of the item and deposited in a body of liquid for storage. The cartridge may cause a net density of the item to exceed a density of the liquid, or to fall below the density of the liquid, and to descend or ascend within the liquid, as desired. The cartridge may also cause a net density of the item to equal the density of the liquid, and thus remain at a constant depth. The cartridge may be configured to receive acoustic signals or other forms of instructions for varying a net density of the item, and may send acoustic signals or other messages identifying a depth or position of the item. The cartridge may thus enable an item to be stored at any depth within the liquid, and be retrieved upon demand.

Abstract: Robotic arms or manipulators can be used to toss inventory items within an inventory system. Tossing strategies for the robotic arms may include information about how a grasped item is to be moved and released by a robotic arm to achieve a trajectory for moving the item to a receiving location. A tossing strategy may also use a trajectory that avoids time and/or space reserved for a trajectory of another tossed item. The receiving location can include surfaces and/or other features that can be manipulated for receiving the item based on one or more characteristics of the tossed item and/or a trajectory of the tossed item.

Abstract: Inventory management systems and related methods employ a catching member to selectively catch items dropped by a robotic manipulator. A related method includes controlling a robotic manipulator to move an inventory item from a first location to a second location. A catching member is selectively positioned to catch the inventory item if dropped by the robotic manipulator prior to the item reaching the second location. The catching member is moved to a suitable location for subsequent processing of one or more items dropped by the first robotic manipulator into the catching member.

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: A system for managing inventory items includes a portable inventory holder and an unmanned drive unit configured to move the inventory holder between locations in an inventory facility. The inventory facility includes a plurality of light emitting elements. The drive unit captures an image of a subset of the light emitting elements. The captured image is processed to determine the location of the drive unit within the facility. A path is determined along which the drive unit moves to an inventory holder and moves the inventory holder to another location. The light emitting elements can be provided by optical fibers embedded in the floor of the inventory facility.

Abstract: A system for managing inventory items includes a portable inventory holder and an unmanned drive unit configured to move the inventory holder between locations in an inventory facility. The inventory facility includes a plurality of uniquely identifiable fiducial markers having a small set of values distributed in a pattern. The drive unit captures at least one image of a subset of the plurality of the fiducial markers. The at least one captured image is processed to determine a location of the drive unit within the facility. A path is determined along which the drive unit moves to an inventory holder and moves the inventory holder to another location. The pattern of fiducial markers can include one or more repeated instances of uniquely identifiable fiducial markers. A fiducial marker can encode information using a readable code and at least one attribute of the fiducial marker.

Abstract: An inventory system includes an inventory holder and a mobile drive unit. The mobile drive unit includes sensors for detecting one or more load characteristics of the inventory holder and/or includes magnets and/or magnetic surfaces for securing the inventory holder to the mobile drive unit during lifting and/or moving.

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: In an infrastructure that uses a mobile order fulfillment system, robotic drive units may be dispatched and instructed to bring inventory holders to a workstation where at least one of the inventory holders is packed and prepared for shipment. The robotic drive units are then instructed to move the prepared inventory holder to a transport vehicle such as a truck. Fiducial marks may be removably placed within the transport vehicle to aid navigation of the robotic drive units. At a destination facility, additional robotic drive units may be instructed to move the inventory holders from the truck and place the inventory holders at appropriate storage locations.

Abstract: A system to provide additional functionality to robots in automated warehouse systems is disclosed. The system can include a number of additional components that can be attached to existing components of the warehouse system to improve safety, functionality, and decrease costs. The system can provide modular tools to enable robots to perform additional tasks without having equipment permanently installed on the robots. The bases or shelves for the automated warehouse system can be equipped with robotic arms, lights, cameras, sensors, actuators and other components to enable a robot to utilize a particular tool for a particular job. The robot and the bases or shelving units can also comprise complementary electronic connections to provide power and/or data communications between the robot, the bases or shelving units, and/or a management module.

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 includes an inventory holder and a mobile drive unit. The mobile drive unit includes sensors for detecting one or more load characteristics of the inventory holder and/or includes magnets and/or magnetic surfaces for securing the inventory holder to the mobile drive unit during lifting and/or moving.

Abstract: An inventory system has mobile drive units that freely and independently move about a facility to transport inventory holders. The mobile drive units may operate through communications with other drive units, or under a more centralized control of a management module. For various operating scenarios, the mobile drive units are directed to shuffle the inventory holders in a manner that minimizes travel of the mobile drive units, thereby improving overall system efficiency. One or more single mobile drive units may be used to transport inventory holders to and from a region, and one or more other mobile drive units may be used to reposition or slide each of the inventory holders back and forth within the region to efficiently place inventory holders before an operator on an as-needed basis.

Abstract: A system for managing inventory items includes a portable inventory holder and an unmanned drive unit configured to move the inventory holder between locations in an inventory facility. The inventory facility includes a plurality of uniquely identifiable fiducial markers having a small set of values distributed in a pattern. The drive unit captures at least one image of a subset of the plurality of the fiducial markers. The at least one captured image is processed to determine a location of the drive unit within the facility. A path is determined along which the drive unit moves to an inventory holder and moves the inventory holder to another location. The pattern of fiducial markers can include one or more repeated instances of uniquely identifiable fiducial markers. A fiducial marker can encode information using a readable code and at least one attribute of the fiducial marker.

Abstract: A system for managing inventory items includes a portable inventory holder and an unmanned drive unit configured to move the inventory holder between locations in an inventory facility. The inventory facility includes a plurality of light emitting elements. The drive unit captures an image of a subset of the light emitting elements. The captured image is processed to determine the location of the drive unit within the facility. A path is determined along which the drive unit moves to an inventory holder and moves the inventory holder to another location. The light emitting elements can be provided by optical fibers embedded in the floor of the inventory facility.

Abstract: A system for managing inventory items includes a portable inventory holder and an unmanned drive unit configured to move the inventory holder between locations in an inventory facility. The inventory facility includes a plurality of uniquely identifiable fiducial markers having a small set of values distributed in a pattern. The drive unit captures at least one image of a subset of the plurality of the fiducial markers. The at least one captured image is processed to determine a location of the drive unit within the facility. A path is determined along which the drive unit moves to an inventory holder and moves the inventory holder to another location. The pattern of fiducial markers can include one or more repeated instances of uniquely identifiable fiducial markers. A fiducial marker can encode information using a readable code and at least one attribute of the fiducial marker.

Abstract: An inventory system has mobile drive units that freely and independently move about a facility to transport inventory holders. The mobile drive units may operate through communications with other drive units, or under a more centralized control of a management module. For various operating scenarios, the mobile drive units are directed to shuffle the inventory holders in a manner that minimizes travel of the mobile drive units, thereby improving overall system efficiency. One or more single mobile drive units may be used to transport inventory holders to and from a region, and one or more other mobile drive units may be used to reposition or slide each of the inventory holders back and forth within the region to efficiently place inventory holders before an operator on an as-needed basis.

Abstract: In an infrastructure that uses a mobile order fulfillment system, robotic drive units may be dispatched and instructed to bring inventory holders to a workstation where at least one of the inventory holders is packed and prepared for shipment. The robotic drive units are then instructed to move the prepared inventory holder to a transport vehicle such as a truck. Fiducial marks may be removably placed within the transport vehicle to aid navigation of the robotic drive units. At a destination facility, additional robotic drive units may be instructed to move the inventory holders from the truck and place the inventory holders at appropriate storage locations.

Abstract: In an infrastructure that uses a mobile order fulfillment system, robotic drive units may be dispatched and instructed to bring inventory holders to a workstation where at least one of the inventory holders is packed and prepared for shipment. The robotic drive units are then instructed to move the prepared inventory holder to a transport vehicle such as a truck. Fiducial marks may be removably placed within the transport vehicle to aid navigation of the robotic drive units. At a destination facility, additional robotic drive units may be instructed to move the inventory holders from the truck and place the inventory holders at appropriate storage locations.

Abstract: In an infrastructure that uses a mobile order fulfillment system, robotic drive units may be dispatched and instructed to bring inventory holders to a workstation where at least one of the inventory holders is packed and prepared for shipment. The robotic drive units are then instructed to move the prepared inventory holder to a transport vehicle such as a truck. Fiducial marks may be removably placed within the transport vehicle to aid navigation of the robotic drive units. At a destination facility, additional robotic drive units may be instructed to move the inventory holders from the truck and place the inventory holders at appropriate storage locations.