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WIRELESS PICK-AND-PACK SYSTEM
CROSS REFERENCE TO RELATED
APPLICATIONS
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This application claims priority from U.S. Provisional Application No. 60/383,772, filed May 30, 2002, and titled WIRELESS PICK-TO-LIGHT PICK-AND-PACK SYSTEM FOR WAREHOUSES, which is incorporated by reference. 10
TECHNICAL FIELD
Various implementations in this description relate generally to communications for identifying product locations and, more particularly, to infrared pick and pack systems.
BACKGROUND
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Manual picking and packing of goods in a warehouse or storage area environment typically involves a human picker traversing a warehouse or similar storage area and selecting, by hand, the goods corresponding to entries in a list. This list is commonly known as a picklist, and as each good in the 25 picklist is selected, the picker typically packs it away for shipment or processing. To increase the accuracy and efficiency of this manual picking and packing of goods, pickto-light systems have been developed. Typical pick-to-light systems provide pickers with a visual cue as to the location 30 of the storage container or storage subarea that contains the goods corresponding to the entries in the picklist. For example, some pick-to-light systems include lights attached to or positioned near each storage subarea (for example, a shelf or designated floor space) or storage container (for 35 example, a bin or a crate) in the storage area. The lights provide a visual cue to the picker by illuminating or flashing if the corresponding storage subarea or storage container contains the goods in the picklist. Other pick-to-light systems include a light emitting diode (LED) display associated 40 with a set of storage containers or storage subareas. The LED display is typically an alphanumeric display that provides a picker with the coordinates of the containers or subareas that contain the goods in the picklist.
Typical pick-to-light systems are limited in both flexibil- 45 ity and efficiency. First, typical pick-to-light systems tend to use fixed wiring to connect the lights or LED displays to their corresponding storage subareas or containers. The fixed wiring makes it difficult to rapidly change the location of goods in the storage area. For example, moving a set of 50 crates from one location to another may require rewiring the lights associated with those crates or, alternatively, may require using entirely different lights and reprogramming the pick-to-light system accordingly. Second, typical pick-tolight systems tend to be ill-suited to support the simulta- 55 neous processing of multiple picklists in the same region of the warehouse. Typical systems may allow such simultaneous processing by introducing yet another cognitive step into the picking process. For example, different colored lights may be used for different picklists, but doing so forces 60 a picker to identify not just which bin has an illuminated light near it but also requires that the picker further determine the color of the light and whether that color corresponds to his or her picklist. Introduction of this extra color determination cognitive step is undesirable in that it may 65 lead to more errors and further decreases the accuracy of the manual picking process. The extremely high accuracy
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demands of manual picking and packing (for example, 99% accuracy) makes introduction of such an added margin of error undesirable.
SUMMARY
One implementation of a pick-and-pack system that provides both flexibility and efficiency includes battery-powered indicator devices that are each coupled to a given storage subarea or storage container within a storage area. The picker traverses the storage area while carrying a mobile computing device that is communicatively coupled to a mobile transmitter. The mobile computing device accesses item entries in a picklist and communicates each item entry to the mobile transmitter one at a time for processing.
Continuing with this implementation, the mobile transmitter sends out a short-range infrared (IR) activation signal that corresponds to the item entry currently being processed. When the picker moves the mobile transmitter into physical proximity to an indicator device, the indicator device senses the IR activation signal and determines whether to respond to the activation signal. Each indicator device will respond only if the IR activation signal includes a specific item identifier code. The item identifier codes are different for each indicator device and are associated with the items stored within the storage subarea or storage container corresponding to that indicator device. The indicator device, therefore, only responds to the IR activation signal if the activation signal is brought physically near the indicator device (for example, to within a predetermined distance such as ten feet) and if the activation signal includes the item identifier code corresponding to that indicator device. The indicator device responds to the IR activation signal by illuminating a light that allows the picker to locate the storage container or storage subarea to which the indicator device is coupled and that will contain the items corresponding to the item entry being processed.
In one general aspect, an apparatus for requesting the location of items in a storage area includes a mobile computing device and a transmitter. The mobile computing device accesses an entry in a list of items to be selected from item storage subareas within an item storage area. The entry is associated with an item identifier code corresponding to an item storage subarea. The transmitter is communicatively coupled to the mobile computing device and is able to transmit a short-range activation signal corresponding to the item identifier code. The short-range activation signal causes an indicator device associated with the item identifier code and in physical proximity to the short-range activation signal to transmit an indicator signal in response to the short-range activation signal that indicates the location of the corresponding item storage subarea.
The mobile computing device may be a personal digital assistant (PDA), similar to devices made by Palm Corporation or iPAQ devices made by HP Corporation, laptop computer or a belt-mounted computer. The mobile computing device may receive the entry in the list of items from an enterprise system. The enterprise system may be an inventory management system. The mobile computing device may receive the entry from the enterprise system by using a docking station or over a wireless network. The wireless network may be a wireless local area network, a wide area radio network, or a cellular modem network. The mobile computing device may include a stationary component and a mobile component.
