Asset management using mobile radio-frequency identification (RFID) readers

Apparatus having corresponding methods and computer programs comprise: a mobile RFID reader adapted to receive radio-frequency (RF) signals from a plurality of RFID tags, wherein each RF signal represents a tag identifier associated with the respective RFID tag, and wherein the RFID tags include a plurality of asset tags and a plurality of location tags, wherein each of the asset tags is associated with a respective one of a plurality of assets, and wherein each of the location tags is associated with a respective one of a plurality of first locations; and an association module adapted to generate first associations between each of the assets and one or more of the first locations based on the tag identifiers.

BACKGROUND

The present disclosure relates generally to radio-frequency identification (RFID). More particularly, the present disclosure relates to asset management using a mobile RFID reader.

In radio-frequency identification (RFID) systems for asset management, each asset is tagged with an RFID tag that emits a radio-frequency (RF) signal representing a tag identifier that can be used to identify the tagged asset. Current RFID systems for asset management are generally implemented using one or more fixed RFID readers permanently deployed in each room where the assets are located. Such systems can generally determine in which room an asset is located. In rooms having multiple RFID readers, current systems can determine an approximate location (zone) of an asset in a room based on the location of the RFID reader receiving the strongest RF signal from the asset.

However, such systems suffer from at least two problems. First, asset tracking at the zone level is not precise enough for most applications. A zone may include many assets, so that a search of the zone for the desired asset can consume considerable time. Second, such systems generally require a large number of RFID readers, making such systems very expensive.

SUMMARY

In general, in one aspect, an embodiment features an apparatus comprising: a mobile RFID reader adapted to receive radio-frequency (RF) signals from a plurality of RFID tags, wherein each RF signal represents a tag identifier associated with the respective RFID tag, and wherein the RFID tags include a plurality of asset tags and a plurality of location tags, wherein each of the asset tags is associated with a respective one of a plurality of assets, and wherein each of the location tags is associated with a respective one of a plurality of first locations; and an association module adapted to generate first associations between each of the assets and one or more of the first locations based on the tag identifiers.

In general, in one aspect, an embodiment features a method comprising: receiving radio-frequency (RF) signals from a plurality of radio-frequency identification (RFID) tags into a mobile RFID reader, wherein each RF signal represents a tag identifier associated with the respective RFID tag, and wherein the RFID tags include a plurality of asset tags and a plurality of location tags, wherein each of the asset tags is associated with a respective one of a plurality of assets, and wherein each of the location tags is associated with a respective one of a plurality of first locations; and generating first associations between each of the assets and one or more of the first locations based on the tag identifiers.

In general, in one aspect, an embodiment features an apparatus comprising: a network interface adapted to receive a plurality of first tag identifiers, wherein each of the first tag identifiers is associated with a respective RFID tag, and wherein the RFID tags include a plurality of asset tags and a plurality of location tags; a RFID database adapted to store a plurality of entries, wherein the entries comprise a plurality of first entries, wherein each of the first entries associates one of the asset tags with a respective one of a plurality of assets, and a plurality of second entries, wherein each of the second entries associates one of the location tags with a respective one of a plurality of locations; and an association module adapted to generate first associations between each of the assets and one or more of the first locations based on the first tag identifiers, the first entries, and the second entries.

In general, in one aspect, an embodiment features a computer program comprising: instructions for receiving a plurality of tag identifiers, wherein each tag identifier is represented by a respective radio-frequency (RF) signal received from a radio-frequency identification (RFID) tag into a mobile RFID reader, wherein the RFID tags include a plurality of asset tags and a plurality of location tags, wherein each of the asset tags is associated with a respective one of a plurality of assets, and wherein each of the location tags is associated with a respective one of a plurality of first locations; and instructions for generating first associations between each of the assets and one or more of the first locations based on the tag identifiers.

The leading digit(s) of each reference numeral used in this specification indicates the number of the drawing in which the reference numeral first appears.

DETAILED DESCRIPTION

Embodiments of the present disclosure provide elements of a low-cost, scalable system for asset management using mobile radio-frequency identification (RFID) readers. The system can operate in several modes, including scan, search, locate, and doorway modes. The system can also include a data entry mode for entry of the operating parameters described below into an operating database. For example, the parameters can include tag ID, asset, location, make, model, serial number, and the like.

In scan mode, a mobile RFID reader receives radio-frequency (RF) signals from RFID tags as the mobile RFID reader is moved relative to the RFID tags. Each RF signal represents a tag identifier associated with the respective RFID tag. The RFID tags include asset tags and location tags. Each asset tag is associated with an asset. Each location tag is associated with a location. For example, the assets can be electronic devices such as computers, each having a respective RFID tag attached, and the locations can be shelving units in which the assets are stored. An association module generates associations between each of the assets and one or more of the locations based on the RF signals. The association module can generate the associations based on times of reception of the RF signals, the order of reception of the RF signals, and the like.

In search mode, an input module accepts an indication of one or more of the assets. Then a search module identifies one or more of the locations based on the indication and the associations generated during scan mode.

In locate mode, an input module accepts an indication of one or more of the assets. Then a locate module generates an alert when an RF signal representing a tag identifier associated with the indicated asset(s) is received by the mobile RFID reader.

In doorway mode, a motion detector and a fixed RFID reader are fixed in a location such as a doorway of a room in which the assets are stored. When the motion detector detects motion in the location, a camera creates an image of the location, and the fixed RFID reader captures any RF signals present in the location. The association module then generates an association among the location, the image, and any assets associated with tag identifiers represented by the RF signals captured by the fixed RFID reader.

FIG. 1shows elements of a radio-frequency identification (RFID) system100in scan mode according to some embodiments. Although in the described embodiments, the elements of RFID system100are presented in one arrangement, other embodiments may feature other arrangements, as will be apparent to one skilled in the relevant arts based on the disclosure and teachings provided herein. For example, the elements of RFID system100can be implemented in hardware, software, or combinations thereof.

Referring toFIG. 1, RFID system100includes five assets102A-E stored in three storage units104A-C. However, embodiments of the present disclosure are scalable to any number of assets102and storage units104. Assets102can include any sort of asset. For example, assets102can include electronic devices and the like. Storage units104can include any sort of storage units as long as the RFID asset tags of the assets102stored therein are sufficiently exposed for reading by an RFID reader. For example, storage units104can include shelving units, disk drive bays and the like. For example, individual disk drives mounted in computer disk drive bays can be tagged individually as assets102, for example using tag hangers to expose the tags for reading.

RFID tags are attached to each asset102and storage unit104. Each RFID tag has a different tag identifier. For clarity of description, the RFID tags attached to assets102are referred to as “asset tags” AT1-AT5, while the RFID tags attached to storage units104are referred to as “location tags” LT1-LT3. However, asset tags AT and location tags LT can be identical except for the tag identifiers encoded therein. RFID tags AT, LT can be implemented in any manner, can be active or passive, and the like.

RFID system100further includes a mobile RFID scanner106in communication with a server computer108over a network110. Network110can be implemented as a wide-area network (WAN) such as the Internet, a local-area network (LAN), or the like. In other embodiments, network110can be replaced by a direct communication link.

Mobile RFID scanner106includes one or more RFID antennas112, a mobile RFID reader114, a client computer116, and a network interface118. RFID antenna(s)112and RFID reader114can be implemented in any manner. For example, RFID antennas112and mobile RFID reader114can be commercially-available units. Client computer116can be implemented as a commercially-available general-purpose computer, as a special-purpose computer, and the like. Network interface118can be implemented in any manner. For example, network interface118can be a commercially-available unit. To further mobility of mobile RFID scanner106, network interface118is preferably a wireless network interface.

Mobile RFID scanner106is shown mounted on wheels120for mobility. In various embodiments, mobile RFID scanner106can be mounted on a standard utility cart, as a handheld unit, and the like. For example, for large warehouse applications, Mobile RFID scanner106can be mounted on a truck, forklift, and the like. In addition, multiple mobile RFID scanners106can be implemented on a single platform or vehicle.

Server computer108includes a network interface122, an association module124, and an RFID database126. Server computer108can be implemented as a commercially-available general-purpose computer, as a special-purpose computer, and the like. Network interface122can be implemented in any manner. For example, network interface122can be a commercially-available unit.

Association module124can be implemented in any manner. For example, association module124can be implemented as a software module for execution by a processor of server computer108. RFID database126can be stored on a memory, storage device, or the like of server computer108.

Before scanning begins, each RFID tag AT, LT is registered in RFID database126. That is, an entry is created in RFID database126for each RFID tag AT, LT. For example, RFID database126can include an asset table for asset tags AT and a location table for location tags LT. Example asset and location tables for the example ofFIG. 1are presented below as Tables 1 and 2, respectively.

Referring to Table 1, each entry for asset tags AT includes the tag identifier encoded into the asset tag AT, along with information describing the tagged asset102such as make, model, serial number, and the like. For clarity of description, reference numbers fromFIG. 1are used as the tag identifiers in Table 1.

Referring to Table 2, each entry for location tags LT includes the tag identifier encoded into the location tag LT, along with information describing the location of the tagged storage unit104such as building number, room number, aisle, storage unit number, and the like. In implementations involving locations in multiple cities, the location information can include, city, state, country, and the like. For clarity of description, reference numbers fromFIG. 1are used as the tag identifiers in Table 2. In addition, it is assumed that storage units104are the first three storage units on aisle A in room222of a one-building implementation.

FIG. 2shows a process200for RFID system100ofFIG. 1in scan mode according to some embodiments. Although in the described embodiments, the elements of process200are presented in one arrangement, other embodiments may feature other arrangements, as will be apparent to one skilled in the relevant arts based on the disclosure and teachings provided herein. For example, in various embodiments, some or all of the steps of process200can be executed in a different order, concurrently, and the like.

Referring toFIG. 2, mobile RFID scanner106is set in motion (step202). The motion of mobile RFID scanner106can be controlled manually or automatically. For example, in a manual implementation, mobile RFID scanner106can be pushed or driven by a human operator past storage units104. As another example, in an automatic implementation, mobile RFID scanner106can automatically follow a magnetic or optical track affixed to the floor past storage units104.

As mobile RFID scanner106moves relative to RFID tags AT, LT, mobile RFID reader114receives radio-frequency (RF) signals from RFID tags AT, LT through RFID antenna112(step204). Each RF signal represents a tag identifier associated with the respective RFID tag AT, LT. Client computer116collects the tag identifiers (step206), and passes the tag identifiers to server computer108, either individually or in batches.

At server computer108, association module124generates associations between assets102and the locations of storage units104based on the tag identifiers received from mobile RFID scanner106(step208). The associations can be generated based on times of reception of the RF signals by mobile RFID reader114, the order of reception of the RF signals, and the like. In the example ofFIG. 1, the tag identifiers are collected in the following order, with mobile RFID scanner106moving from left to right inFIG. 1: LT1, AT1, AT2, LT2, AT3, LT3, AT4, AT5. With knowledge that the each location tag LT is mounted on the left side of a storage unit104, association module124creates the associations shown in Table 3, referred to as the cross-reference table, which is added to RFID database126.

Tables 1-3 together now define associations between assets102and their locations in storage units104. These associations can be used in search mode, locate mode, and doorway mode, as described below. Referring to Table 3, note that each asset102can have multiple locations if desired.

FIG. 3shows elements of a radio-frequency identification (RFID) system300in search mode according to some embodiments. Although in the described embodiments, the elements of RFID system300are presented in one arrangement, other embodiments may feature other arrangements, as will be apparent to one skilled in the relevant arts based on the disclosure and teachings provided herein. For example, the elements of RFID system300can be implemented in hardware, software, or combinations thereof.

Referring toFIG. 3, RFID system300includes a client computer302in communication with server computer108over network110. Server computer108and network110can be implemented as described above.

Client computer302can be implemented as a commercially-available general-purpose computer, as a special-purpose computer, and the like. Client computer302includes a network interface304, an input module306, and a search module308. Input module306and search module308can be implemented in any manner. For example, input module306and search module308can be implemented as software modules for execution by a processor of client computer302. In other embodiments, all or part of input module306and search module308can be implemented on server computer108.

Network interface304can be implemented in any manner. For example, network interface304can be a commercially-available unit.

FIG. 4shows a process400for RFID system300ofFIG. 3in search mode according to some embodiments. Although in the described embodiments, the elements of process400are presented in one arrangement, other embodiments may feature other arrangements, as will be apparent to one skilled in the relevant arts based on the disclosure and teachings provided herein. For example, in various embodiments, some or all of the steps of process400can be executed in a different order, concurrently, and the like.

Search module308identifies one or more locations based on the user-provided indication of asset(s)102and the associations in RFID database126(step404). For example, if the user indicates asset102C, search module308indexes the cross-reference table (Table 3 above) using the asset tag identifier AT3, which returns the location tag identifier LT3. Search module308then indexes the location table (Table 2 above), which returns the location as Room222, Aisle A, Unit2. Server computer provides the location to mobile RFID scanner106using network interfaces122and118.

Alternatively, location tags can be placed more densely than one per storage unit104. In these embodiments, search module308can return the locations that surround the asset102. For example, assume that storage units104A-C are not separate storage units, but form a single storage unit104. In such embodiments, search module308can return the location of asset102C as being between location tags LT2and LT3in Room222, Aisle A.

FIG. 5shows elements of a radio-frequency identification (RFID) system500in locate mode according to some embodiments. Although in the described embodiments, the elements of RFID system500are presented in one arrangement, other embodiments may feature other arrangements, as will be apparent to one skilled in the relevant arts based on the disclosure and teachings provided herein. For example, the elements of RFID system500can be implemented in hardware, software, or combinations thereof.

Referring toFIG. 5, RFID system500includes five assets102A-E stored in three storage units104A-C. RFID system500further includes mobile RFID scanner106in communication with server computer108over a network110. Mobile RFID scanner106includes one or more RFID antennas112, a mobile RFID reader114, a client computer116, and a network interface118. Server computer108includes a network interface122, an association module124, and an RFID database126. Each of these elements can be implemented as described above.

FIG. 6shows a process600for RFID system500ofFIG. 5in locate mode according to some embodiments. Although in the described embodiments, the elements of process600are presented in one arrangement, other embodiments may feature other arrangements, as will be apparent to one skilled in the relevant arts based on the disclosure and teachings provided herein. For example, in various embodiments, some or all of the steps of process600can be executed in a different order, concurrently, and the like.

Referring toFIG. 6, input module502accepts an indication of one or more assets102(step602). For example, input module502can provide a graphical user interface (GUI) where a user can enter one or more search parameters such as values for the fields shown in Table 1. That is, a user can specify the make, model, serial number, and the like, of the asset102to be located. Alternatively, input module502can provide a GUI listing some or all of the assets102in RFID database126, allowing the user to select one or more of the assets102. Mobile RFID scanner106sends the indication of the asset(s) to server computer108. In particular, network interface118of mobile RFID scanner106transmits the indication, and network interface122of server computer108receives the indication. Association module124of server computer108identifies one or more tag identifiers associated with the one or more assets102based on the indication. Server computer108provides the tag identifiers to mobile RFID scanner106using network interfaces122and118.

Mobile RFID scanner106is then set in motion (step604), for example as described above. As mobile RFID scanner106moves relative to RFID tags AT, LT, mobile RFID reader114receives radio-frequency (RF) signals RFID tags AT, LT through RFID antenna112(step606), also as described above. When an RF signal representing a tag identifier associated with the asset(s)102to be located is received by mobile RFID reader114(step608), locate module504generates an alert (step610). The alert can take any form, such as a sound, light, or the like.

FIG. 7shows elements of a radio-frequency identification (RFID) system700in doorway mode according to some embodiments. Although in the described embodiments, the elements of RFID system700are presented in one arrangement, other embodiments may feature other arrangements, as will be apparent to one skilled in the relevant arts based on the disclosure and teachings provided herein. For example, the elements of RFID system700can be implemented in hardware, software, or combinations thereof. As another example, although RFID system700is described as monitoring a doorway, RFID system700can be used to monitor any location.

Referring toFIG. 7, RFID system700may include a doorway module702in communications with server computer108over network110. Server computer108and network110can be implemented as described above.

Doorway module702monitors a doorway704, and includes a motion detector706, a fixed RFID reader710, and a network interface712, and can optionally include a camera708. Doorway module702can also include a monitor module714to manage motion detector706, fixed RFID reader710, and camera708. These elements can be implemented in any manner. For example, motion detector706, RFID reader710, and network interface712can be implemented as commercially-available units, and camera708can be implemented as a commercially-available IP camera or the like.

FIG. 8shows a process800for RFID system700ofFIG. 7in doorway mode according to some embodiments. Although in the described embodiments, the elements of process800are presented in one arrangement, other embodiments may feature other arrangements, as will be apparent to one skilled in the relevant arts based on the disclosure and teachings provided herein. For example, in various embodiments, some or all of the steps of process800can be executed in a different order, concurrently, and the like.

Referring toFIG. 8, when motion detector706detects motion in doorway704(step802), optional camera708creates one or more images of doorway704(step804), and fixed RFID reader710captures any RF signals present in doorway704(step806). Network interface712transfers the image(s), and the tag identifiers represented by the captured RF signals, to server computer108, using network interfaces118and122.

At server computer108, association module124generates an association among doorway704, the image(s), and any assets102associated with the tag identifiers (step808). The association can be recorded in RFID database126of server computer108. This association can also include other information, such as the time and date of each image. This association can be useful when an asset102cannot be found in search mode or locate mode. Doorway mode can also be used to update the locations of assets102, for example to indicate that an asset102has left the room.

The images associated with the asset102can be used to identify the last person that had possession of the asset102, to identify an intruder and aid in their prosecution, and the like. Multiple images of the person can be useful to improve the ability to identify the person. For example, the gap between images in a series can be approximately 1 second. If the asset still cannot be found, security personnel can use the images to investigate.

In some embodiments, the mobile RFID scanner is implemented as a standalone unit. In such implementations, the association module and RFID database are incorporated into the mobile RFID scanner. Therefore, no separate server is needed.FIG. 9shows elements of a radio-frequency identification (RFID) system900including a standalone mobile RFID scanner906according to some embodiments. Although in the described embodiments, the elements of standalone RFID system900are presented in one arrangement, other embodiments may feature other arrangements, as will be apparent to one skilled in the relevant arts based on the disclosure and teachings provided herein. For example, the elements of standalone RFID system900can be implemented in hardware, software, or combinations thereof.

Referring toFIG. 9, RFID system900includes five assets102A-E stored in three storage units104A-C. Assets102and storage units104are tagged as described above. RFID system900further includes a standalone mobile RFID scanner906. Mobile RFID scanner106includes one or more RFID antennas112, mobile RFID reader114, client computer116, association module124, and RFID database126. The elements of standalone mobile RFID scanner906can be implemented as described above, and can operate in any of the modes described above.

While several modes of operation have been described above separately, it should be understood that these modes can be used alone or in combination. Furthermore, functions and apparatus of the different modes can be combined into a single apparatus implementing multiple modes.

A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the scope of the disclosure. Accordingly, other implementations are within the scope of the following claims.