U.S. patent application number 09/874749 was filed with the patent office on 2002-12-05 for radio frequency identification in document management.
Invention is credited to Erickson, David P., Kelliher, William J. JR., Sainati, Robert A., Waldner, Michele A..
Application Number | 20020180588 09/874749 |
Document ID | / |
Family ID | 25364482 |
Filed Date | 2002-12-05 |
United States Patent
Application |
20020180588 |
Kind Code |
A1 |
Erickson, David P. ; et
al. |
December 5, 2002 |
Radio frequency identification in document management
Abstract
Various systems and methods of handling items such as files are
disclosed, including systems and methods for polling RFID-tagged
items while they are stored in storage areas.
Inventors: |
Erickson, David P.;
(Stillwater, MN) ; Kelliher, William J. JR.; (Lino
Lakes, MN) ; Sainati, Robert A.; (Bloomington,
MN) ; Waldner, Michele A.; (Minneapolis, MN) |
Correspondence
Address: |
Office of Intellectual Property Counsel
3M Innovative Properties Company
P.O. Box 33427
St. Paul
MN
55133-3427
US
|
Family ID: |
25364482 |
Appl. No.: |
09/874749 |
Filed: |
June 5, 2001 |
Current U.S.
Class: |
340/10.2 |
Current CPC
Class: |
G06K 19/07796 20130101;
G06K 17/00 20130101 |
Class at
Publication: |
340/10.2 |
International
Class: |
H04Q 005/22 |
Claims
We claim:
1. A method of minimizing interactions between overlapping RFID
tags, wherein the method comprises the step of intentionally
staggering the location of RFID tags on consecutive items to which
RFID tags are applied.
2. A method of minimizing interactions between overlapping RFID
tags, wherein the method comprises the steps of: (a) determining an
order in which items are to be placed in a storage area; and (b)
intentionally staggering the location of RFID tags on consecutive
items in the order.
3. A method of minimizing interactions between overlapping RFID
tags, wherein the method comprises the steps of: (a) applying RFID
tags to items; (b) providing information in a database that is
indicative of the location of the RFID tag on the item; and (c)
using the information to select successive items for a storage area
so that instances of overlapping RFID tags are minimized.
Description
TECHNICAL FIELD
[0001] The present invention relates to document management and
file management, and specifically the use of radio frequency
identification systems for document and file management.
BACKGROUND OF THE INVENTION
[0002] At least two patent publications describe the use of radio
frequency identification (RFID) systems for document or file
management. One is U. S. Pat. No. 5,689,238 (Cannon, Jr. et al.),
which according to its abstract describes methods and systems for
locating objects using electronic tags that are attached to the
object before it is stored. To locate the object, the response code
associated with the tag on that object is entered into an
interrogator, and the interrogator sends a signal that causes the
tag to emit a sound, or a signal.
[0003] Another publication is PCT published application WO
00/16280, and specifically at page 23, line 11 through page 24,
line 5. That portion of the PCT publication references a filing
cabinet having drawers, each of which stores file folders. The file
folders may be provided with an RFID tag. In use, a controller
sequentially polls antennae in the drawers of the filing cabinet.
The controller detects response signals or codes, and thus can
determine which files are in the drawers.
[0004] The present invention is related to improvements in fields
of this type.
SUMMARY OF THE INVENTION
[0005] A number of embodiments of the present invention are
described herein, some of which are summarized below.
[0006] In a first embodiment of the invention, a method is provided
for minimizing interactions between overlapping RFID tags, wherein
the method comprises the step of intentionally staggering the
location of RFID tags on consecutive items to which RFID tags are
applied. In a second embodiment of the invention, a method is
provided for minimizing interactions between overlapping RFID tags,
wherein the method comprises the steps of (a) determining an order
in which items are to be placed in a storage area; and (b)
intentionally staggering the location of RFID tags on consecutive
items in the order. In a third embodiment of the invention, a
method is provided for minimizing interactions between overlapping
RFID tags, wherein the method comprises the steps of (a) applying
RFID tags to items; (b) providing information in a database that is
indicative of the location of the RFID tag on the item; and (c)
using the information to select successive items for a storage area
so that instances of overlapping RFID tags are minimized.
[0007] In a fourth embodiment of the invention, a guide is provided
for positioning successive RFID tags on successive items, wherein
the guide includes an indication of more than one position at which
an RFID tag may be located relative to the item, so that an RFID
tag may be applied to each successive item in a position different
from the previous item. In a fifth embodiment of the invention, a
method is provided for minimizing interactions between RFID tags,
wherein the method comprises the step of providing a guide that
includes an indication of more than one location at which an RFID
tag can be located on an item.
[0008] In a sixth embodiment of the invention, an RFID tag is
provided, comprising an RFID element including an integrated
circuit and an antenna, a substrate, and a repositionable adhesive
that enables the RFID tag to be attached to a surface, detached
from the surface, and reattached to a surface. In a seventh
embodiment of the invention, a repositionable tag is provided for
mounting on a file folder, comprising, (a) an RFID tag; and (b) a
support for the RFID tag. In an eighth embodiment of the invention,
a file folder is provided comprising an RFID tag that can be
repositioned at different locations on the file folder to minimize
interactions between the RFID tag and another RFID tag.
[0009] In a ninth embodiment of the invention, a method is provided
for minimizing interactions between RFID tags associated with
adjacent items, the method comprising the step of providing a
surface on which the items rest, the surface including structures
that position each successive item at a different vertical position
than the previous item. In a tenth embodiment of the invention, the
ninth embodiment of the invention includes a surface that is a
shelf, and items that are files, and the structures position each
successive file at a different vertical position than adjacent
files. In an eleventh embodiment of the invention, a method is
provided for minimizing interactions between RFID tags associated
with adjacent items, the method comprising the steps of (a)
providing a surface adjacent the items; and (b) providing a
structure that positions each successive item at a different
horizontal position than the previous item. In a twelfth embodiment
of the invention, the eleventh embodiment of the invention includes
items that are files, and the files are supported by shelves. In a
thirteenth embodiment of the invention, a file folder is provided
comprising an RFID tag, the file folder including a spacer for
maintaining a predetermined minimum thickness in the area of the
RFID tag so as to minimize interactions between the RFID tag and
another RFID tag.
[0010] In a fourteenth embodiment of the invention, an RFID tag is
provided including a light source that can be activated when the
RFID tag is interrogated. In a fifteenth embodiment of the
invention, a method is provided for identifying an item that is
associated with an RFID tag, the method comprising the steps of (a)
interrogating the RFID tag; and (b) illuminating a light source
associated with at least one of the item and the RFID tag to
indicate that the RFID tag has been interrogated by an RFID reader.
In a sixteenth embodiment of the invention, the item of the
fifteenth embodiment of the invention is at least one of (a)
misplaced; (b) identified on a list of items available to an RFID
reader that interrogates the RFID tag; (c) a candidate for
archiving or destruction; and (d) adjacent to a misplaced item.
[0011] In a seventeenth embodiment of the invention, a method is
provided for determining a desired location for an item, the method
comprising the steps of (a) identifying an item adjacent to the
desired location, the item being associated with an RFID tag; (b)
interrogating the RFID tag; and (c) illuminating a light source
associated with the RFID tag to indicate that the desired location
is adjacent to the item. In an eighteenth embodiment of the
invention, a storage area is provided, comprising (a) a desired
location for an item; (b) an item bearing an RFID tag, wherein a
light source is associated with at least one of the item and the
RFID tag, the RFID-tagged item being adjacent to the desired
location.
[0012] In a nineteenth embodiment of the invention, a system is
provided for locating an item of interest within a container that
holds other items, the item of interest and the container each
including an RFID tag, wherein a light source is associated with
the container whereby the light source may be illuminated when the
RFID tag associated with either the item of interest, the
container, or both is interrogated by an RFID reader. In a
twentieth embodiment of the invention, at least one of the item of
interest and the container of the nineteenth embodiment of the
invention is (a) misplaced; (b) identified on a list of items
available to an RFID reader that interrogates the RFID tag; (c) a
candidate for archiving or destruction; and (d) adjacent to a
misplaced item.
[0013] In a twenty-first embodiment of the invention, a method is
provided for interrogating a storage area that includes a number of
items each bearing an RFID tag, the method comprising the step of
polling designated portions of the storage area more frequently
than other portions of the storage area. In a twenty-second
embodiment of the invention, the method of the twenty-first
embodiment of the invention further includes automatically polling
designated portions of the storage area more frequently than other
portions of the storage area based on information determined from
polling. In a twenty-third embodiment of the invention, the
frequency of the polling of the method of the twenty-first
embodiment of the invention depends on the number of items that
have been removed from or returned to the storage area. In a
twenty-fourth embodiment of the invention, the frequency of polling
of the twenty-first embodiment of the invention depends on the
number of people who have used the storage area.
[0014] In a twenty-fifth embodiment of the invention, a method is
provided for interrogating a storage area that includes a number of
items each bearing an RFID tag, the method comprising the steps of
(a) providing a polling schedule for polling the RFID tags; and (b)
preempting the polling schedule to poll a designated portion of the
storage area, prior to polling the RFID tags according to the
polling schedule. In a twenty-sixth embodiment of the invention, a
method is provided for interrogating a storage area that includes
items each bearing an RFID tag, the method comprising the steps of
(a) providing a polling schedule for polling the RFID tags; and (b)
providing a user interface associated with the RFID polling system
that enables a user to alter the polling schedule by increasing or
decreasing the number of times that a portion of the storage area
is polled relative to other portions of the storage area.
[0015] In a twenty-seventh embodiment of the invention, an RFID
polling system is provided, comprising (a) an antenna system for
polling RFID tags associated with items stored in a storage area;
(b) a controller for controlling which portion(s) of the storage
area are polled; (c) a polling schedule that designates which the
order in which portions of the storage area are polled; and (d) a
user interface that enables a user to alter the polling schedule by
increasing or decreasing the number of times that a portion of the
storage area is polled relative to other portions of the storage
area. In a twenty-eighth embodiment of the invention, an RFID
polling system is provided, comprising (a) an antenna system for
polling RFID tags associated with items stored in a storage area;
(b) a controller for controlling which portion(s) of the storage
area are polled; (c) a polling schedule that designates which the
order in which portions of the storage area are polled; and (d) a
detection system that detects activity in portions of the storage
area, whereby the polling schedule is altered based on information
provided by the detection system. In a twenty-ninth embodiment of
the invention, the alteration in the polling schedule of the
twenty-eighth embodiment of the invention is proportional to the
activity detected.
[0016] In a thirtieth embodiment of the invention, a method is
provided for polling RFID-tagged items, comprising the steps of (a)
providing a list of items for a user to locate; and (b) polling the
last-known locations for the items on the list prior to the user
searching for the items. In a thirty-first embodiment of the
invention, a method is provided for interrogating a storage area
that includes items each bearing an RFID tag, the method comprising
the steps of (a) providing a polling schedule for polling the RFID
tags; (b) monitoring portions of the storage area to detect
activity; and (c) altering the polling schedule based on the
activity detected. In a thirty-second embodiment of the invention,
a method is provided for polling RFID tags associated with items in
a storage area, the method comprising the steps of (a) providing a
database including information identifying the current location of
each item within the storage area; and (b) updating the database
using information from polling the storage area for items being
removed or replaced. In a thirty-third embodiment of the invention,
the entire storage area of the thirty-second embodiment of the
invention is polled periodically to obtain a census of every
RFID-tagged item in the storage area.
[0017] In a thirty-fourth embodiment of the invention, a method is
provided for locating the approximate position of an item bearing
an RFID tag within a storage area, comprising the steps of (a)
providing an antenna on each side of the item, the antennas being
adapted to interrogate the RFID tag; (b) interrogating the RFID tag
using both antennas; and (c) identifying that the item is located
closer to one of the antennas if only that antenna is able to
interrogate the item successfully, and identifying that the item is
located approximately in the center of the two antennas if each
antenna is able to interrogate the item successfully. In a
thirty-fifth embodiment of the invention, a storage area is
provided, comprising (a) an antenna shelf tape for interrogating
RFID tags associated with items stored in the storage area; and (b)
at least one light source within the storage area, the light source
adapted to be illuminated when an RFID tag located in proximity to
the light source is interrogated.
[0018] In a thirty-sixth embodiment of the invention, a system is
provided for tracking items associated with RFID tags, comprising
(a) a check-out station for interrogating an RFID tag, and for
updating a database to indicate that the item has been checked-out;
and (b) a timer for tracking the amount of time for which the item
has been checked-out. In a thirty-seventh embodiment of the
invention, the system of the thirty-sixth embodiment of the
invention further comprises (c) a notification system for sending a
notification if the amount of time that an item has been
checked-out exceeds a predetermined amount of time. In a
thirty-eighth embodiment of the invention, the notification of the
thirty-seventh embodiment of the invention is by e-mail. In a
thirty-ninth embodiment of the invention, the e-mail of the
thirty-eighth embodiment of the invention is sent to a person who
checked the item out.
[0019] In a fortieth embodiment of the invention, a system is
provided for RFID-tagged items, comprising (a) a storage area for
RFID-tagged items, the storage area including an RFID reader for
detecting the presence of RFID-tagged items; and (b) a notification
system for notifying a user that at least one RFID-tagged item is
in the storage area and awaiting the user's action. In a
forty-first embodiment of the invention, an RFID system is
provided, comprising (a) an antenna system for transmitting write
command signals to RFID tags; (b) a storage location for storing
items of interest, each of which includes an RFID tag; and (c) an
RFID writer in operative connection to the antenna system, wherein
the RFID writer is adapted to write identical information to each
RFID tag within range of an antenna to which a write command signal
is directed.
[0020] In a forty-second embodiment of the invention, a container
system is provided, comprising (a) a container for holding a
plurality of items each associated with a barcode; (b) an RFID tag
associated with the container; and (c) a database entry associating
the RFID tag with the items. In a forty-third embodiment of the
invention, a container system is provided, comprising (a) a
container for holding a plurality of items each associated with a
bar-code; (b) an RFID tag associated with the container; and (c)
information stored within a memory on the RFID tag that is
sufficient to identify the bar-codes.
[0021] In a forty-fourth embodiment of the invention, a method is
provided for associating items that are each associated with a
barcode with a single RFID tag, comprising the step of creating an
entry in a database associating the bar-coded items with the single
RFID tag. In a forty-fifth embodiment of the invention, the method
of the forty-fourth embodiment of the invention comprises scanning
each barcode with a barcode scanner, and associating the barcode
with the single RFID tag in a database.
[0022] In a forty-sixth embodiment of the invention, a method is
provided for associating items that are each associated with a
barcode with a single RFID tag, comprising the step of writing to
the memory of the RFID tag information sufficient to identify the
barcodes. In a forty-seventh embodiment of the invention, the
method of the forty-sixth embodiment of the invention comprises
scanning each barcode with a barcode scanner, and associating the
barcode with the single RFID tag in the memory of the RFID tag.
[0023] In a forty-eighth embodiment of the invention, the use of an
RFID-based tracking system in a medical facility is disclosed,
wherein (a) patient files each include an RFID tag; (b) a patient
file storage location includes an RFID reader that is connected to
a database, for checking files into and out of the storage location
and updating the database accordingly; and (c) at least one office
in which a patient file is used includes an RFID reader for
detecting the presence of the file, the reader being connected to
the database to provide current information regarding the location
of the file.
[0024] In a forty-ninth embodiment of the invention, the use of an
RFID-based tracking system in a legal office is disclosed, wherein
(a) client files each include an RFID tag; (b) a client file
storage location includes an RFID reader that is connected to a
database, for checking files into and out of the storage location
and updating the database accordingly; and (c) at least one office
in which a client file is used includes an RFID reader for
detecting the presence of the file, the reader being connected to
the database to provide current information regarding the location
of the file.
[0025] In a fiftieth embodiment of the invention, the use of a
portable RFID reader in combination with a storage area including a
polling system for polling RFID-tagged items is disclosed, wherein
information from the polling system is provided to the portable
RFID reader to enable a user to locate an RFID-tagged item. In a
fifty-first embodiment of the invention, the use of a portable RFID
reader for checking items into or out of inventory, or both, is
disclosed, wherein a user interrogates an RFID tag associated with
the item, and provides information to the portable RFID reader,
using a user interface associated with the RFID reader, to indicate
whether the item is being checked into or out of inventory. In a
fifty-second embodiment of the invention, a method is provided for
checking items into or out of inventory, comprising the steps of
(a) providing a mobile storage area including an associated RFID
tag; (b) associating at least two RFID-tagged items with the
RFID-tagged mobile storage area; and (c) checking the items into or
out of inventory by interrogating- the RFID tag associated with the
mobile storage area, and not interrogating the RFID-tagged items.
In a fifty-third embodiment of the invention, the fifty-second
embodiment of the invention is modified by checking the items into
or out of inventory by a method other than interrogation of an RFID
tag associated with the mobile storage area.
DESCRIPTION OF THE DRAWINGS
[0026] The present invention will be described with reference to
the attached FIGS. 1 through 9, as described below.
DESCRIPTION OF THE INVENTION
[0027] Despite some interest in converting offices to paperless
environments in which paper documents are entirely replaced by
electronic versions of those documents, a number of industries
continue to rely heavily on paper documents. Examples include law
offices, government agencies, and facilities for storing business,
criminal, and medical records. Although in some instances these
records are stored in enclosed filing cabinets, in many cases the
files are positioned on open shelve of the type shown in FIG. 1.
Documents and files can also be found in other locations, including
on desks and tables, in drawers, or on carts. Although the various
aspects of the present invention will largely be described in the
context of files or documents or both, the invention may be used in
tracking other items including books, video tapes,
optically-recorded media, or retail items, pallets, containers, or
other assets, as appropriate, whether or not each of these items is
specifically called out as an alternative application.
[0028] Various aspects of the present invention will be described
beneath certain headings below, but persons of ordinary skill in
the art will immediately recognize that certain features described
in one part of this description may be used in conjunction with
features in other parts of this description, and thus the headings
are intended to be a helpful guide, not a limiting boundary.
[0029] I. Smart Labels or Tags
[0030] RFID tags or labels are made by various manufacturers
including Texas Instruments of Dallas Tex., under the designation
"Tag-It". Another type of RFID tag is actually a combination tag
that includes an RFID element and a magnetic security element, and
is described in U.S. Pat. No. 6,154,137, which is assigned to the
assignee of the present invention, the contents of which is
incorporated by reference herein. An RFID tag typically includes an
integrated circuit with a certain amount of memory, a portion of
which may be used by the manufacturer to write certain information
to the tag (and perhaps lock it to protect it from being changed or
overwritten), and another portion of which may be used by a
purchaser to store additional information to the tag. The
integrated circuit is operatively connected to an antenna, as also
shown in FIG. 2, that receives RF energy from a source and also
transmits RF energy in a manner well known in the art. It is this
transmitted RF energy that provides a signal that may be received
by an interrogator or reader to obtain information about the RFID
tag, and the item with which it is associated. RFID tags may
operate in one or more different frequency ranges, such as the
Tag-It RFID tags sold by Texas Instruments, which operate at 13.56
MHz.
[0031] RFID tags may be associated with or applied to items of
interest, as described above. The tag may even be embedded within
the item or the packaging of the item so that the tag is at least
substantially imperceptible, which can help to prevent detection
and tampering. Thus it would be possible to "source-mark" items
with an RFID tag, such as inserting an RFID tag into or applying an
RFID tag to an item during its manufacture, as with a book, compact
disc, consumer product, file folder, pallet, carton, box-sealing
tape, shipping label, or the like.
[0032] In many file rooms, color-coded file folders are used to
help users organize records. Colors may be used for categories or
sorting. An RFID element could be embedded or added to the
color-coded label. A separate color could, for example, be used to
indicate that a file has been converted, meaning that an RFID tag
or label has been attached to it, so that a user can quickly
determine which files are still awaiting conversion and which have
already been converted. If a folder were sold with embedded RFID
capability, the memory on the RFID tag could be pre-programmed to
include the color-coding information.
[0033] One potential difficulty in tagging items with RFID tags can
occur when the items are very thin, or more specifically when the
RFID tags are overlapping and in approximately the same plane. For
example, file rooms such as those shown in FIG. 1 may include thick
files containing many papers, but may also contain thin files that
are empty or contain only a small number of papers. If individual
pages are tagged with RFID tags, then those tags also may overlap
when, for example, the papers are stacked in a pile or collected in
a file. When RFID tags overlap, they can become difficult to
interrogate (or read) reliably with an RFID interrogator (or
reader). Without wishing to be bound by any particular scientific
theory regarding the cause of that difficulty, it is believed that
two RFID tags that overlap each other may respond at a different
frequency than either tag does alone. The next aspect of the
present invention relates to solutions for tag-tag interaction
problems.
[0034] One method of overcoming undesirable tag-tag interaction is
to reduce the degree to which adjacent tags overlap each other.
This can be done by systematically staggering the locations of RFID
tags associated with file folders, documents, containers, or other
items so that it is very unlikely that the tags on two adjacent
items would overlap each other to any substantial degree. This may
not eliminate the potential problem, but would substantially
decrease it. The systematic staggering of tags could be done
automatically by a machine that is adapted to position each tag at
a position different from that of the last tag it applied to an
item. It could also be done manually, perhaps in conjunction with a
guide that shows the user where to position each tag. For example,
if one tag is positioned at location A on an item, the guide may
show positions A, B, C, D, and E so that the user can simply select
the next successive position when applying a tag to the next item.
It should be noted that incidental differences in the location of
tags on items, such as may happen when tags are manually or
automatically applied by a machine in only approximately the same
location each time, are not considered to be staggered tags within
the meaning of the present invention because incidental differences
would not be sufficient to overcome the tag-tag interaction
problems noted above.
[0035] Another method of overcoming undesirable tag-tag
interactions is to make the tag repositionable, so that a user who
notes that the tag is located adjacent to another tag can move one
or both tags to new locations on the items so that no significant
interactions take place. This could be done by providing each RFID
tag with a repositionable adhesive, such as those adhesives used on
repositionable labels or paper notes generally, so that a tag
adhered to an item can easily be removed and repositioned. Another
similar method is to provide the RFID tag in or on a repositionable
tab on the item, such as a file folder, so that the tab can be
moved to a desired location, as shown in FIG. 3. These tags could
be repositioned along the top, side, or other portion of the item
to which they are attached.
[0036] Alternatively, RFID tags can be staggered based on a
database or other information. For example, the user could indicate
which item was next to receive a tag. The system would look into a
database of known records that are going to be filed nearby. Then,
a non-overlapping position would be computed for the user to affix
the tag. The calculated position could be displayed on a computer
monitor, or directly on the file with a light beam or the like (as
shown in FIG. 4), or the calculated position could be transmitted
to a device that would automatically apply the tag in the
appropriate location. In another embodiment, instead of determining
the tag placement based on the filing order, the filing order could
be based on the tag placement. That is, files could be placed on a
shelf based on their tag locations, so that adjacent files do not
have overlapping RFID tags. This may or may not be used in
conjunction with a random filing system (in which files may be
located anywhere in the storage area).
[0037] Items may also be arranged so that the tags are in
essentially identical locations on each item, but the items are
positioned at different positions relative to each other within the
storage location. For example, in the case of files stored on a
shelf, some type of structure that changes the shelf from a
continuous flat surface to a surface having varying heights along
its length could be used to offset adjacent items from each other.
The shelf structures could be placed on the storage locations, or
made integral with the storage locations, as desired. The
structures may have, for example, a sawtooth profile, a ramp
profile, an undulating profile, or other similar profiles that have
the same effect, as shown in FIG. 5. Another alternative would be
to position adjacent files, for example, at different distances
from the front edge of the shelf, so that the RFID tags would then
also be at different locations relative to each other. This could
be done by providing shelf structures (or structures in storage
locations generally) that only permit alternating items to be
inserted a full distance into the storage location, which would
provide for staggered locations of tags by virtue of the positions
of adjacent items, and not the positions of the tags on the
items.
[0038] Another way to address the tag-tag interaction problem is to
provide items or structures that provide for a specified minimum
distance between adjacent tags. For example, each tag could include
a bumper or structure (either added to the tagged item or formed in
or on the tagged item) that prevents another item from being closer
than the specified minimum distance. For example, a file folder may
be embossed to provide such a bumper that projects from the
remainder of the folder, so that the tag is essentially recessed
relative to the bumper. Another way to do the same thing is to tag
only items having a certain minimum thickness, such as file folders
that are more than 1.27 cm (0.5 inch) thick. Then if each item is
tagged on the same surface, such as the left-hand side of the file
folder, it would remain at least the specified distance away from
each adjacent tag. This could be done in the case of file folders
by providing a spacing strip within or outside the folder, in which
the strip maintains the specified minimum thickness of the folder.
Other similar embodiments may be used for items having different
forms. In another "spacing" embodiment, a rigid portion could be
built into the bottom of each folder to comprise part of the bottom
and enforce the minimum width, yet allow the rest of the folder to
expand as needed to accommodate a variable amount of folder
contents. This is illustrated in FIG. 6. A tag could also be
embedded in plastic and inserted along the spine of the folder or
book, as shown in FIG. 7.
[0039] II. RFID Tag that can be Illuminated When Interrogated
[0040] As noted above, when conventional RFID tags are
interrogated, they emit a response that can be detected by an RFID
reader. Information regarding the item to which the tag is attached
may then be displayed on a display associated with the RFID reader,
or the RFID reader may emit a sound indicating that a tag has been
interrogated.
[0041] In another aspect of the present invention, an RFID tag is
provided that includes a light source that can be illuminated when
the tag is interrogated. The light source could be an LED or other
suitable source, and could be powered by a battery provided on the
RFID tag (which would be referred to as an "active" tag), or by
energy transmitted to the RFID tag by the REID reader or another
source (which would be referred to as a "passive" tag). When a user
wishes to search for a specific item, the REID reader can be
programmed to emit a signal that instructs the RFID tag or tags
that meet a certain description to respond by illuminating the
light source, or returning an RFID signal to the RFID reader, or
both. This visual indication makes the task of locating a specific
item much easier, particularly if the item is stored with a large
number of like items.
[0042] Another feature related to the one described just above is
the illumination of a light source associated not with a specific
item of interest, but instead with the items stored on either side
of the item of interest. This could be useful when returning the
item of interest to a storage location, and could be done by
causing the RFID reader to emit a signal that instructs the tags
known to be located on either side of the item of interest to be
illuminated.
[0043] Items are often stored in storage locations in a
predetermined order. For example, library materials are stored in a
predetermined order, as are medical and other types of files. In
another embodiment of the present invention, the light source
described above could be illuminated when the position of the item
to which it is attached does not correspond to its position in the
desired order. In other words, items that have been mislocated
could be illuminated, which would enable a user to obtain those
files, determine their correct location (perhaps by interrogating
the RFID tag again and obtaining its location either from
information contained only on the tag, or from an existing
database, or a combination of the two), and relocate them. In a
related embodiment, items that meet a certain description may be
illuminated following interrogation, such as any items that are
believed by an inventory control system to be missing or checked
out, damaged, or eligible for archiving or disposal. For example,
files that are believed to have been checked out of the file room,
but are located by the RFID reader in the file room, may be
illuminated in the manner described above to permit a user to find
them easily.
[0044] Items are often stored together within a common container,
and an RFID tag is associated with each of the items and with the
common container. For example, a number of files may be tagged and
stored within a larger accordion folder that also bears an RFID
tag. These RFID tags may also include a light source of the type
previously described, so that common containers that are missing
one or more items may be located, or so that items that are
mislocated within a common container may be located.
[0045] III. Smart Storage Areas
[0046] A smart storage area is one that is equipped with RFID
interrogation capability so that it can read the RFID tags
associated with the items stored in the storage area. One
application of this aspect of the invention is for tracking and
locating files or documents bearing RFID tags. A system of this
type is illustrated in FIG. 1. Antennas are positioned on the
shelves so that they can read the RFID tags associated with the
files. The antennas may be positioned in various ways, such as on
top of each shelf, at the back of the shelves, or supported
vertically, interspersed among the files. The antennas can be
retrofitted to existing shelves or built into a shelf and purchased
as a unit.
[0047] The antenna or antennas associated with the storage area can
interrogate, or poll, the RFID tags continuously. If polling is
done continuously, a controller (perhaps including a circuit for
multiplexing signals through the antennas sequentially) can cause
the antennas to interrogate portions of the storage area in a
predetermined order. The antenna system may include one or more
smart nodes that control a subset of antennas. The number,
location, and other characteristics of the antennas associated with
a given node may be determined by the user. For example, if it is
desired to poll the shelves quickly, more nodes may be added to the
system. Another approach is for the user to configure or customize
the polling system so that nodes or portions of the storage area
may be configured to poll in a sequence specified by the user. For
example, if one portion of the storage area is unavailable for use
at certain times, then the RFID tags in that area need not be
interrogated during those times. A more sophisticated schedule for
polling could involve interrogation of high-use or important areas
more frequently than low-use or less important areas. Important
areas may be areas in which items of high value are located, or
areas in which theft or unauthorized acquisition of items is
suspected, or areas where the transfer of items is more frequent
than in other areas. This polling system can also be customized
using software that enables the user to specify the frequency with
which certain areas of the storage area are interrogated. For
example, some areas (such as shelves in a file storage area) could
be set up to poll the RFID tags only once or twice a day, or when
there is known to have been activity in that portion of the storage
area, while other areas could poll RFID tags more frequently.
[0048] In another embodiment of the invention, an intermediate or
master RFID tag may include information related to RFID tags in a
local area. That information may be re-written periodically, so
that the master RFID tag includes current information regarding the
other RFID tags. The master RFID tag does not itself interrogate
other tags, but instead serves as a local repository or database of
information related to local RFID tags. Then, a fast inventory may
be taken simply by interrogating only the master RFID tags.
[0049] If a user is going or has recently been to an area to shelve
or remove records, she may want that area to be immediately polled
to update location information for those file locations. Then,
instead of continuously polling all shelves, the system would focus
on polling only the area of interest as specified by the user. This
kind of event-driven polling may provide the advantage of faster
updating for files of interest.
[0050] Even when a polling schedule has been set by a user, the
system may permit that schedule to be altered either temporarily or
permanently. For example, the storage area (such as a set of
shelves for files) may include a button or display that enables a
user to request more frequent polling or less frequent polling.
This may be done in response to an increase in activity or a
decrease in activity, and these requests for alteration of the
polling schedule may in this manner preempt the standard polling
schedule for a defined period of time (one hour, one day, or one
week, for example), or simply alter the polling schedule for the
future. The alteration of the polling schedule could even be
automated. For example sensors, such as optical sensors, placed in
or near a storage area to detect activity in that area, and the
automated polling system could accordingly decrease, increase, or
leave the polling schedule unchanged based on the activity level
detected. For example, optical sensors may detect an increased
number of people passing through a door into a room containing
medical records, and if the number of people detected is more than
20% more than a predetermined number, the sensor could send a
signal to the controller and the controller could alter the polling
schedule so that the monitored area is polled more frequently.
There could even be a direct correlation between the activity level
detected by the optical or other sensor and the polling frequency,
so that a 15% decrease in traffic results in a 15% decrease in
polling activity, and a 27% increase in traffic results in a 27%
increase in polling activity. The correlation between detected
traffic and polling frequency need not be exact, or even
proportional, but may be approximate. Polling could also be
activated when even a single access to a storage area is detected
by a sensor.
[0051] In a related embodiment, a polling schedule may be altered
based on information obtained from a database. That information may
be simply how many items have been removed from or replaced in a
particular storage area, or may reflect the proportion of file
removals and replacements in a particular storage area relative to
other storage areas. In another embodiment, polling may be
increased in an area where one or more files have been checked out,
until those files have been returned.
[0052] As an alternative (or supplement) to polling by taking a
complete census of all tagged items, the system could instead
detect changes in the presence or absence of items. For example, if
the system database includes information regarding the current
location status of all items, such as files, then the system may
only need to track changes (removals, additions) to maintain
accurate status information. This type of tracking system could be
referred to as "differential polling," and may provide a
performance advantage because the presence or absence of the tagged
items can be determined by the database without a complete polling
of all shelves. Periodic polling of the entire area may still be
desirable to confirm the accuracy of the database, even when a
differential polling system is used. As an example, a database may
include the "circulation status" of various items such as books,
files, or pallets, meaning that the database includes information
indicating whether the item is supposed to be present in the
storage area or not. Then, rather than polling every RFID tag in
the entire storage area, the system may "instruct" each antenna or
node to report back to the controller any items that are missing
compared to the last time the area was polled, as opposed to
reporting all items that are present. This may require memory
associated with each antenna or node, but may result in a savings
of time. A complete inventory may in any event be conducted at the
end of each day, for example.
[0053] A single file may be interrogated as it is removed from or
replaced on a shelf By keeping track of just those individual files
that are being removed or added, the system can maintain an
accurate inventory database. The removal or addition of items such
as files may be detected by two or more sensors that when used
together provide an indication of the direction that an item has
moved, and can thus determine whether the item is entering or
leaving the storage area. Another useful embodiment includes a user
interface, which may include a button or display, such as a touch
panel display, that a user uses to indicate whether an item is
being added to or removed from the storage area. In another
embodiment, an antenna in a particular portion of the storage area,
such as a shelf, can be activated to interrogate the RFID-tagged
items on that shelf to update the inventory database. It may be
useful to provide some type of indicator (audio, visual, or both)
that confirms for a user that an item has been removed or added to
the storage area. This differential inventory system, and others of
its kind described herein, differ from other differential inventory
systems at least in that the removal or addition activity is
detected at the storage location itself, and not at a check-in or
check-out station when those transactions are typically
recorded.
[0054] Another aspect of the present invention is that of masking
RFID tags from interrogation while the items to which they are
attached are in a stored position in a storage area, and unmasking
the RFID tags when the items are removed from or added to the
storage area. For example, tag-tag interaction could be maximized,
rather than minimized, so that as long as files remain adjacent to
each other, they cannot be interrogated. When files are removed or
added, the RFID tags do not interact with each other, and the file
being removed or added can be interrogated by an RFID reader
antenna, such as an antenna shelf tape. In another embodiment, RFID
tags could be shielded, or could be in contact with a metal shelf,
so that the tags cannot be read in a stored position but can be
read as they are being removed from or replaced on a shelf Systems
of this type may be much faster than standard RFID interrogation
systems, because the RFID tags associated with most items cannot
respond to interrogation, and only a selected few files that are
being removed from or added to the storage area can be
interrogated.
[0055] Resolution of Position within a Storage Area
[0056] For some applications it may be sufficient to know only
whether a tagged item is within a storage area of interest. For
other applications, however, it may be most useful to know not only
whether an item is within a storage area of interest, but also
where the item is located in absolute terms (perhaps by position
within a bin or on a shelf), relative terms (relative to other
tagged items), or both. For example, it may be useful to know that
a file is in the middle quarter of the top shelf, that the file is
between files labeled "Coyle" and "Coyne," or both.
[0057] One basic way of determining shelf position using
fixed-position antennas (as opposed to a portable RFID reader with
an antenna) is to place an antenna at each end of the shelf If the
antennas have ranges that overlap slightly, then if the antenna on
the left end of the shelf detects the item, the item is known to be
toward the left end of the shelf The same principle applies on the
right end of the shelf If both antennae detect the item, then the
item is known to be in the center of the shelf Greater resolution
can be gained by adding additional antennas.
[0058] Another method of indicating position is to provide one or
more light sources on or near the storage area, such as along the
edge of a shelf The light sources, which could be LEDs, could be
used in conjunction with an antenna shelf tape of the type
described in PCT Publication No. WO 00/10112, the contents of which
is incorporated by reference herein. In that manner, when an
antenna detects that an RFID tag of interest is near that antenna,
a light source may be illuminated to attract the attention of a
user to that portion of the storage area. The light source could
also or instead be used for indicating that an item has been
misplaced in the area of the light source. Antenna shelf tape, and
the light sources described herein, can of course be used for other
storage areas.
[0059] Another useful feature of the present invention is that of
notification. Software associated with the smart storage area
system can begin tracking the time from check-out of an item until
check-in, and can issue a notification of overdue items. For
example, if an item may only be checked out for 14 days, the
software may begin a counter when the item is checked out, issue a
notification to the user after 14 days, and issue a notification to
a staff member after 21 days if the item has not been returned. The
notification may be an e-mail message, a list, an audio alarm, or
another suitable type of notification either to the person to whom
the item was charged out, or to another interested person or
system. This notification system could be completely automated, so
that an e-mail message is sent automatically to the person to whom
the item was charged out, or a computerized telephone call is
placed to the person's telephone number. This has the advantage of
reducing staff time associated with reminding people to return
overdue files. Other aspects of the notification feature include,
for example, the notification of pending work for an individual or
group based on the detection of items such as files in an area
designated for review by that individual or group. An example may
be an area designated for upcoming matters for attorneys, where
files related to those matters may be placed in advance of their
respective deadlines. The attorney may then be notified that the
file is ready for review. Similarly, if patient files are located
in a designated area, a medical professional may be notified
(perhaps through a cellular telephone or a pager) that the file
(and perhaps the person to whom the file relates) is ready for
review. Lastly, the notification system may notify a records system
administrator when items that are indicated in a database as
present are not detected during a polling cycle, so that the
administrator may manually search for the file either in the
storage area or elsewhere.
[0060] In another embodiment, a user can request a particular item
or group of items, such as a file or a group of books. The smart
storage system can then report to the user the last location at
which the items were located within the storage area, and can as
described above illuminate a light source associated with the item
or the location, or both. Optionally, the system can re-poll the
last-known location at which the item was detected to verify that
the item was in the location indicated in the database.
[0061] Reading Information from and Writing Information to RFID
Tags in Smart Storage Areas
[0062] It is often advantageous to write certain data to tags so
that those data can be accessed even when the reading device is not
connected to a database and does not have access to a database. The
smart storage areas of the present invention may also be adapted to
update or add to the information stored on the RFID tags. This is
done by using the programming or "writing" capability associated
with RFID readers, in conjunction with the antennas provided in the
storage areas for communication with the RFID tags. This method is
particularly useful when identical information is to be stored on a
large number of RFID tags, because a person is not required to
obtain all of the tagged items manually for individual processing.
For example, if a records retention schedule is stored on the tag,
that data could be automatically written to tags on or in the smart
storage area as new retention dates are computed. Conversely, tag
data can be read while in or on a smart storage area. A user may
want to obtain specific information from the RFID tag associated
with a particular item, such as a file, and can obtain those data
via a computer interface to the smart storage area without having
to locate the actual file. Reading and writing could occur from any
place there is network access to the system. The mass update of
files may be useful when, for example, a group of files will be
transferred to a new location, or will be designated for archiving
or destruction on the same date in the future. In these instances,
software for mass updating of all the RFID tags (or the database
entries associated with the respective RFID tags) can be activated
by a user or automatically.
[0063] IV. Portable RFID Readers
[0064] Portable RFID readers are disclosed in patent publications
including U.S. Pat. No. 6,232,870, which is assigned to the
assignee of the present invention and is incorporated by reference
herein. One preferred embodiment of a portable RFID reader is a
handheld reader of the type shown generally in FIG. 8, which
includes an RFID reader, an antenna, a processor, a display, and a
power supply. The display is part of a user interface that provides
information to a user or receives information from a user, or both.
The portable RFID reader typically also includes a system for
communicating with a database, which may be a wireless
communications system, or a removable media system in which
information can be stored by the RFID reader to the removable media
and the media then removed and used to upload information to or
download information from a database associated with another
computer. The communications system could also or instead include a
wired (tethered) link for exchanging information. Another method of
transferring information is to dock the RFID reader, or a portion
of the reader (such as the computer and display, if those are
provided as part of a handheld computer such as a Palm Pilot or
TRGPro), and then to update the databases in a manner commonly used
in connection with handheld computers. Other details of the
portable RFID reader are provided in the publication incorporated
by reference above.
[0065] A portable RFID reader can be used in conjunction with a
smart storage area. For example, a list of items that a user wishes
to locate could be loaded into the portable RFID reader, along with
the corresponding locations where those items are expected to be
found based on the information obtained the last time that the RFID
tags were polled. For example, a list of files and their locations
may be loaded into the portable RFID reader. The portable reader
can then guide the user (perhaps using graphics, words, or the like
provided on the user interface) toward the location for the files
that the user wishes to locate. A database associated with the
portable RFID reader can indicate which items have been retrieved
and which items have not yet been located. At the conclusion of a
particular search, the user can easily produce a list of the items
that haven't yet been retrieved by, for example, producing a report
or viewing a list directly on the display of the portable device.
The data can be transferred to the handheld devices by one or more
of the communications links described above.
[0066] In another embodiment, a portable RFID reader such as a
handheld RFID reader may be used to check items into and out of
inventory. That is, the user may interrogate an RFID tag associated
with an item, indicate through a user interface that the items is
being checked into or out of inventory, as appropriate, and replace
or remove the item, respectively. The updated inventory information
may be stored on a database associated with the RFID reader, such
as one stored in memory integral to the reader, or a removable data
storage device, and that information can be uploaded to another
computer as needed by one or more of the communications links
described above.
[0067] A combination RFID/bar code system could also be used in the
following manner. It may be desirable for a collection of barcoded
items to be tracked using an RFID system. If the cost of the RFID
tags or the cost of placing RFID tags on or in the items is not
justified, then a group of barcoded items may be placed in a single
container or in a storage area having one or more RFID tags, and
the individual items can be associated with that tag or tags in a
database. This can be done by scanning each barcode with a barcode
scanner as the item is placed into the container or storage area.
Then the items can be located in the container or in the storage
area without the cost of converting each item to an RFID
tagged-item.
[0068] V. RFID Readers
[0069] Some items such as files are difficult to track once they
are taken from the main storage area. As illustrated in FIG. 9, for
example, RFID readers can be placed throughout a facility to
improve tracking and locating items of interest. Options for
specific RFID reader designs include small shelves, such as those
that could be located in an office, an in/out basket, a bin, a
chart holder mounted to a wall, or the like. Each such reader
includes read and write capability as with the smart storage area.
The readers could be designed to hold and store items, or as a
simple pad on which a tagged item is temporarily placed until the
RFID tag can be interrogated by the reader. RFID readers may also
be mounted on a wall, or around part or all of a portal such as a
door or a pass-through window.
[0070] Another feature of the invention is the ability to position
an RFID reader in or near each of several areas to which a tagged
item may be taken. For example, medical records may be tracked by
placing an RFID reader in each clinic, doctor's office, reception
area, and temporary file location(s). It may also be advantageous
for these RFID readers to read stacked items, such as files,
without having to position the items in a certain orientation, in
part because users are more likely to use the system regularly if
it is simple to use. One method of accomplishing this aspect of the
invention is to place multiple antennas under, behind, next to,
and/or above the area where the tagged items are going to be
temporarily positioned. These antennas and the associated RFID
reader(s) can be placed in as many or as few locations as the user
desires.
[0071] When RFID readers are positioned in the manner described
just above, the readers can act as automatic check-in and/or
check-out devices. That is, the system may be configured so that
whenever an item is detected by a particular RFID reader, that item
is then checked out (meaning temporarily associated with a person,
entity, or location, for example) to the person or location to
which the RFID reader is associated. As noted above, if check-in
and check-out procedures are both simple, accurate, and convenient
(for example if an RFID reader is located near where items
requiring a particular action are normally located, such as files
that require dictation, transfer to another site, or are ready to
be re-filed), user compliance is likely to increase.
[0072] In another aspect of the present invention, information
related to the frequency of item movements can be used to improve
planning. For example, information indicating the number of items
moved to or from a particular area may be used to allocate
personnel to areas with higher activity and away from areas with
lower activity. Information of that kind may also be used to
determine when to assign additional personnel to an area based on
activity level. In the case of file management, if the system
detects many more files being returned than normal, additional
staff may be allocated to the file return area in time. That
information may also be used to detect the activity levels of
individual users or groups of users, and the person or group who
maintain the item inventory (such as a file tracking database) can
contact the users and perhaps customize the item management system
to serve the frequent users more effectively. In another aspect of
the invention, items indicated as having been checked in and
checked out more frequently than other items may be made available
to users on a different basis, such as electronically through a
computer network, over an intranet or the Internet, or otherwise.
Items indicated as having been checked in and checked out less
frequently than other items may be scheduled for archiving or
destruction, as appropriate. As described above, the system can
send automatic notifications to the person or group to whom the
item has been charged out, to the system administrators, or to
another person or group.
[0073] Items such as files that are interrogated by RFID readers
can improve work flow planning in other ways also. For example, a
particular RFID reader may be associated with a storage area such
as a bin or shelf that should be taken to a different storage
location. By monitoring the activity and number of files detected
by that particular RFID reader, the appropriate time to move the
items may be scheduled most effectively.
[0074] Multiple RFID readers may be connected to a networked
computer, or may be portable and then docked (as with a handheld
computer or portable RFID reader) with a computer and the data
exchanged (synchronized). Those readers could also be part of a
centralized polling system, or each RFID reader could be connected
to its own computer that is itself "polled" by another computer on
demand. The multiple RFID readers could transfer information to a
computer by a wireless network connection.
[0075] VI. Transporting RFID-Tagged Items
[0076] The present invention also includes within its scope a
mobile smart storage area, such as a "smart cart" of the type shown
in FIG. 10. For convenience, mobile smart storage areas will be
referred to herein as smart carts, though they may take a different
form than that illustrated or described. Each smart cart may itself
have an RFID tag, or another identification means such as a
wireless link, a cable (for hot-synching), or a user interface,
which enables the cart and/or all of the items such as files on the
cart to be checked in or checked out of inventory at one time. If
the items are already associated with the cart (perhaps due to
interrogation of the associated RFID tags either by an RFID cart
reader, or by another portable RFID reader), then the task of
interrogating each item individually can be eliminated. This can be
done with any of the storage areas of RFID readers described
herein. A smart storage area may also detect the presence of a
mobile smart storage area, and provide an indication (such as
activating a light source) of where to place certain tagged items
within the smart storage area.
* * * * *