Patent Application
20070187496
The present application relates to inventory tracking processes, systems and devices.
Radio frequency identification (“RFID”) technology has been used for wireless (i.e., non-contact, non-line of sight) automatic identification. A RFID system typically includes a RFID transponder, which is sometimes referred to as an inlet, inlay or tag, and a RFID reader. The transponder typically includes a radio frequency integrated circuit (“RFIC”) and an antenna. Both the antenna and the RFIC can be positioned on a substrate. The inlet, inlay or tag includes the antenna and may also include a substrate on which the antenna is positioned.
The RFID reader utilizes an antenna and a transceiver, which includes a transmitter, a receiver, and a decoder incorporating hardware and software components. Readers can be fixed, tethered, or handheld devices, depending on the particular application. When a transponder passes through the read zone of a reader, the transponder is activated by the electromagnetic field from the reader antenna. The transceiver decodes the data sent back from the transponder and this decoded information is forwarded to a host computer for processing. Data transfer between the transponder and transceiver is wireless.
RFID systems may utilize passive, semi-passive, or active transponders. Each type of transponder may be read only or read/write capable. Passive transponders obtain operating power from the radio frequency signal of the reader that interrogates the transponder. Semi-passive and active transponders are powered by a battery, which generally results in a greater read range. Semi-passive transponders may operate on a timer and periodically transmit information to the reader. Active transponders can control their output, which allows them to activate or deactivate apparatus remotely. Active transponders can also initiate communication, whereas passive and semi-passive transponders are activated only when they are read by another device first. Multiple transponders may be located in a radio frequency field and read individually or simultaneously.
Inventory tracking systems are currently being developed that utilize RFID technology to track location of inventory. For example, it has been proposed to install readers at fixed locations, such as at a loading dock, that can read RFID tags passing nearby. When a RFID tag is read by the reader, the tracking system can determine that an item carrying that RFID tag is at a particular location (i.e., near the reader). It is desirable to provide other inventory tracking systems and methods.
In an aspect, a method of tracking inventory movement using a material handling device is provided. The method includes utilizing automatic identification objects positioned at predetermined locations about a perimeter of a zone, each automatic identification object having zone determining information that is readable by a reader. The zone determining information from at least one automatic identification object is obtained using a reader that is carried by the material handling device. Zone determining information is obtained from a source different from the at least one automatic identification object. The zone determining information obtained from the at least one automatic identification object and the source different from the at least one automatic identification object is processed to identify that the material handling device is moving into the zone.
In another aspect, a method of tracking inventory movement using a material handling device is provided. The method includes utilizing automatic identification objects positioned at predetermined locations about a perimeter of a zone, each automatic identification object having zone determining information that is readable by a reader. An inventory unit is engaged using a power-operated mechanism of the material handling device that is configured to engage the inventory unit during a transport operation whereby the inventory unit is moved from one location to a different location. The material handling device includes a reader. The zone determining information is obtained from at least one automatic identification object using the reader. Zone determining information is obtained from a source different from the at least one automatic identification object. The zone determining information obtained from the at least one automatic identification object and the source different from the at least one automatic identification object is processed to identify that the inventory unit is moving into the zone.
In another aspect, a method of tracking inventory movement using a material handling device is provided. The method includes utilizing automatic identification objects positioned at predetermined locations about perimeters of multiple zones, each automatic identification object having zone determining information that is readable by a reader. The zone determining information is obtained from at least one automatic identification object using a reader that is carried by the material handling device. Zone determining information is obtained from a source different from the at least one automatic identification object. The zone that the material handling device is moving into is determined by processing the zone determining information obtained from the at least one automatic identification object and the source different from the at least one automatic identification object.
In a fourth aspect, an inventory tracking system includes a plurality of zones. A plurality of automatic identification objects are positioned at predetermined locations about perimeters of the zones, each automatic identification object having zone determining information that is readable by a reader. A material handling device includes a reader configured to obtain zone determining information from the automatic identification objects. A processor processes zone determining information obtained by the reader and zone determining information obtained from a source different from the at least one automatic identification object to determine which of the plurality of zones the material handling device is moving into.
In a fifth aspect, a method of tracking inventory movement using a material handling device is provided. The method includes crossing a zone boundary. The zone boundary is at least partially defined by an array of automatic identification objects positioned at predetermined locations about a perimeter of a zone, each automatic identification object having zone determining information that is readable by a reader. Zone determining information is obtained from at least one of the automatic identification objects using a reader to determine that the reader is crossing the zone boundary into the zone. With the reader moving into the zone, it is determined that the reader is moving into the zone regardless of which of the automatic identification objects zone determining information is obtained from.
In yet another aspect, a method of tracking inventory using a computer system that receives information transmitted by a material handling device is provided. The method includes utilizing automatic identification objects positioned at predetermined locations about the perimeters of multiple zones, the automatic identification objects having zone determining information. A reader on the material handling device is utilized to read inventory information from an automatic identification object associated with an inventory unit. The inventory information is transmitted to the computer system. As the material handling device moves into one of the zones, zone determining information is obtained from at least one automatic identification object positioned at the predetermined location using the reader and zone determining information is obtained from a source different from the at least one automatic identification object. The zone determining information obtained from the at least one automatic identification object and the source different from the at least one automatic identification object is transmitted to the computer system to identify that the material handling device is moving into the zone.
The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.
Referring to
The system utilizes a material handling device, in this example, vehicle 14 in the form of a forklift truck. Vehicle 14 is movable, e.g., manually and/or automatically and includes a manually and/or automatically power-operated material handling mechanism 16 that can be used for moving the inventory unit 12 from one position to a different position during a material handling operation. During such material handling operations, the vehicle 14 can read automatic identification objects in the form of transponders that lie beneath or embedded within the warehouse floor 18 along strips 20 and 22. In some embodiments, strips 20 and 22 may include visual indicia such as painted lines that allow a user to visually identify the strips.
In the illustrated example, each aisle 24 and 26 includes a pair of strips 20, 22 located at opposite sides of the aisle. In some embodiments, each aisle 24, 26 includes only a single strip of transponders located at a side of the aisle. As used herein, the term “transponder” refers to an electrical device that receives a specific signal and automatically transmits a reply that may include zone determining information. The term “zone” refers to an area or region set off as distinct, while the term “zone determining information” refers to information (e.g., in the form of a number, alphanumeric character, direction, heading, etc.) that can be used in identifying a particular zone.
In the illustrated embodiment, the transponders are RFID tags that include an integrated circuit connected (e.g., electrically coupled, either by direct contact or by capacitive coupling) to an antenna. The integrated circuit may include semiconductor circuits having logic, memory, RF circuitry, and may be a silicon-based chip, a polymer-based chip and the like. Data may be stored in the integrated circuit of the RFID tags (e.g., using EEPROM or SRAM, laser programming, etc.) and can be transmitted through the connected antenna.
Referring to
The vehicle 14 includes a reader 36 (sometimes referred to as an interrogator) for use in activating and receiving data from RFID tags 38 embedded in the floor 18 in strips 20, 22. The reader 36 may be controlled by a processor 44 such as a microprocessor or digital signal processor, which may be carried by the vehicle 14. In other embodiments, the processor may be located externally of the vehicle 14 or may be incorporated within the reader 36. Any suitable reader may be used. Exemplary readers 36 include a Model 0101-0092-04 Sensormatic® EPC Reader is commercially available from Tyco International, Ltd and a Model “REAL” EPC Reader (MPR-3118, 3114 or 4114) is commercially available from Applied Wireless ID.
Reader 36 communicates with tags 38 via an antenna 42. Antenna 42 is mounted to receive the zone determining information from a RFID tag 38 embedded in the floor 18. Reader 36 is also capable of communicating with a computer or processor, such as on-board computer 44 or a computer or processor embedded within the reader 36. In some embodiments, reader 36 (and/or computer 44) may communicate with an off-board computer or processor 46 (represented by dotted lines). Computer 44, 46 may further process or link information obtained from the RFID tag 38 to another site, such as the Internet, for offsite monitoring. In some embodiments computer 44, 46 may be linked to a data management system, such as a warehouse management system or database, for example, that includes inventory component information in memory. In certain embodiments, computer 44, 46 may provide instructions and/or information to be transmitted to the RFID tag 38 through reader 36 and stored in the tag. Computer 44, 46 may also provide instructions and/or display information to an operator based at least in part on information received from the RFID tag 38. In embodiments including on-board computer 44, the computer 44 may provide instructions and/or display information to a user operating the vehicle 14. Information may also be provided by computer 44 to a warehouse management system which, in turn, based upon business logic or rules provides instructions and/or displays information to an operator based on information received from the tags 38 and/or other zone determining information.
Computer 44, 46 utilizes an application (e.g., a software application) that interfaces with the reader 36 to command the reader-to interrogate and obtain the RFID tag 38 zone determining information, which may be in the form of a tag identification number, and processes the zone determining information obtained from the RFID tag. An association table is stored in memory that relates the particular zone determining information to a particular strip 20, 22. The application further includes an algorithm for processing the zone determining information obtained from one or more RFID tags 38 to determine the zone the vehicle 14 is moving into.
In some embodiments, it is desirable that each of the RFID tags 38 include a unique identification number. Often, this unique identification number is preprogrammed into the RFID tags 38, for example, by the manufacturer of the RFID tag. Each RFID tag 38 can be interrogated to retrieve its identification number and the number can be stored into memory. Using preprogrammed RFID tags can reduce cost relative to custom programming the RFID tags with an identification number. However, in some embodiments, it may be desirable to use RFID tags that are programmed with a selected identification number (e.g., the RFID tags may be writable or rewritable). In certain implementations, it may be desirable to program multiple tags with the same identification number. Referring still to
Table I below is an illustrative example of an association table for mapping consecutively obtained RFID tag identification numbers to a particular zone.
For example, reading the columns from left to right, the first column of characters may correspond to the first obtained identification number from a first strip of RFID tags, the second column of characters may correspond to the second obtained identification number from a second strip of RFID tags and the third column of characters may correspond to the associated zone.
In some instances, it maybe desirable for the application to automatically report a boundary crossing into a zone (e.g., see the rows of Table I indicating “SendLocation”). The boundary crossing or zone may be automatically reported, for example, to the computer 44, 46 for system updating and/or to a graphical interface. In other instances, it may be desirable to report the zone determined using the association table only after the occurrence of a triggering event (e.g., such as a load put down, load pick up event, etc.) for system updating and/or to a graphical interface (e.g., see the rows of Table I without the “SendLocation” command).
In an alternative embodiment represented by
The computer-assisted system can be used to track vehicle 14 movement between zones. Referring now to
As an example, vehicle 14 is shown at zone A and moving in the direction of arrow 53 toward zone C. In crossing from zone A to zone C, vehicle 14 will read a RFID tag associated with strip 20a and then a RFID tag associated with adjacent strip 20b to obtain two consecutive identification numbers which can be processed to determine that vehicle 14 is crossing a boundary between zones A and C and is moving into zone C. It should be realized that vehicle will remain at zone C until zone determining information is again retrieved from RFID tags of adjacent strips, which indicates that the vehicle 14 is crossing another boundary between zone C and an adjacent zone. Additionally, regardless of the approach of the vehicle 14 across the boundary and into zone C (e.g., from zone B or D into zone C), the RFID tags are arranged such that the consecutive reads of RFID tags will identify the vehicle's movement into zone C. As indicated above with reference to
Referring now to
The manufacturing and warehouse facility 54 includes multiple threshold tag arrays 60, 62, 64 and 66. The threshold arrays 60, 62, 64 and 66 are each disposed at an entrance or doorway 98 providing access to spaces within the facility. Threshold array 60 is used to determine vehicle and product movement between primary storage zone 68 and temporary storage zone 70, threshold array 62 is used to determine vehicle and product movement between primary storage zone 68 and primary storage zone 72, threshold array 64 is used to determine vehicle and product movement between receiving zone 74 and at pre-production storage zone 76, and threshold array 66 is used to determine vehicle and product movement between pre-production storage zone 76 and manufacturing zone 78. Of course, other configurations are possible.
The threshold arrays 60 and 62 are further used to determine vehicle and product movement into respective regions D and B within primary storage zone 68. Primary storage zone 68 is subdivided into multiple zones A-D in a fashion similar to that described with reference to
Depending on the application, various types of RFID tags 38 may be used. Tags 38 are typically classified as active or passive. A passive tag has no internal power supply and receives power from an outside source. An active tag includes an internal power source. In some applications, passive tags may be preferred due to, e.g., relatively small size and low cost. In other applications, active tags may be preferred due to relatively long transmit ranges and large memories. Tags 38 may be read-only (i.e., stored data can be read but not changed), writable (i.e., data can be added), rewritable (i.e., data can be changed or re-written), or some combination of each. Suitable, commercially available passive tags 38 may include, for example, an AD-410 single dipole tag (Class 1) available from Avery Dennison, ALN-9340-R “Squiggle™” (Class 1) available from Alien Technology Corporation, Symbol Dual Dipole (Class 0) available from Symbol Technologies, and ALL-9334-02 “2×2” Tag (Class 1) available from Alien Technology Corporation.
The above-described computer-assisted system can be used with a variety of inventory handling devices. For example, referring to
In some embodiments, if the paper roll 58 (or other inventory unit) is moved from a first zone to a different zone, information regarding this relocation may be stored in the RFID tag 82. This product relocation information may also be stored or updated in memory accessible by the tracking system and/or warehouse management system. For example, in one embodiment, vehicle 80 may include a sensor (not shown) for use in detecting an inventory pick up and/or put down event and for responsively sending a signal to the computer 44 indicating that an inventory pick up or put down event has occurred. The sensor may, for example, be a pressure sensor that capable of monitoring pressure in a hydraulic line of the material handling mechanism. The computer 44 can process the zone determining information, the inventory unit identifications and an inventory load or unload signal to identify that the inventory unit has been placed in or picked up from a particular zone. The computer 44 can also communicate this information to a secondary computer.
Referring to
The systems and methods described above can be utilized to provide a number of benefits in real time, including the ability to track the location of inventory, improve warehouse utilization, improve the placement of inventory, provide independent shipment verification, and provide an electronic physical inventory. Movement of the material handling device into a particular zone can be determined without any need for determining a precise location, for example, using relatively complex location tracking systems, such as GPS. The systems and methods may be used to identify and track a variety of inventoried products for a variety of industries.
While various features of the claimed invention are presented above, it should be understood that the features may be used singly or in any combination thereof. For example, other demarcation tools may be used such as laser scanning systems, laser triangulation systems and optical triangulation systems. In some instances, it may be possible to locate the one or more strips of RFID tags overhead or to the side of the material handling device. Therefore, the claimed invention is not to be limited to only the specific embodiments depicted herein.
Further, it should be understood that variations and modifications may occur to those skilled in the art to which the claimed invention pertains. The embodiments described herein are examples of the claimed invention. The disclosure may enable those skilled in the art to make and use embodiments having alternative elements that likewise correspond to the elements of the invention recited in the claims. The intended scope of the invention may thus include other embodiments that do not differ or that insubstantially differ from the literal language of the claims. The scope of the present invention is accordingly defined as set forth in the appended claims.
