U.S. patent application number 10/944324 was filed with the patent office on 2005-02-24 for object control and tracking system with zonal transition detection.
This patent application is currently assigned to Key-Trak, Inc.. Invention is credited to Maloney, William C..
Application Number | 20050040232 10/944324 |
Document ID | / |
Family ID | 26796671 |
Filed Date | 2005-02-24 |
United States Patent
Application |
20050040232 |
Kind Code |
A1 |
Maloney, William C. |
February 24, 2005 |
Object control and tracking system with zonal transition
detection
Abstract
An improved object tracking and control system is provided and
is particularly suited to implementation at an automobile
dealership. The system includes a Key Track system adapted to
control access to and log the check out and check in of keys to
vehicles on the lot. RFID tags are provided on the vehicles and tag
readers are embedded at selected locations within the dealership
parking lot to detect movement of vehicles. In one embodiment, the
lot is subdivided into zones and the readers are located at
transition regions between the zones. Information about the check
out and check in of keys from the Key Track system is combined and
integrated with information about the movement of vehicles about
the lot to reach conclusions regarding authorized movement and to
provide useful information to dealership management.
Inventors: |
Maloney, William C.;
(Marietta, GA) |
Correspondence
Address: |
WOMBLE CARLYLE SANDRIDGE & RICE
POST OFFICE BOX 7037
ATLANTA
GA
30357-0037
US
|
Assignee: |
Key-Trak, Inc.
|
Family ID: |
26796671 |
Appl. No.: |
10/944324 |
Filed: |
September 16, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10944324 |
Sep 16, 2004 |
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10459792 |
Jun 12, 2003 |
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10459792 |
Jun 12, 2003 |
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10172291 |
Jun 14, 2002 |
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10172291 |
Jun 14, 2002 |
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09392267 |
Sep 9, 1999 |
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6427913 |
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60099954 |
Sep 11, 1998 |
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Current U.S.
Class: |
235/385 ;
235/383; 340/10.1; 340/539.13 |
Current CPC
Class: |
G08B 13/1427 20130101;
G08B 21/0227 20130101; G08B 13/2417 20130101; G08B 13/1463
20130101; G08B 13/2448 20130101; G08B 13/2471 20130101; G08B
13/2474 20130101; G08B 13/1454 20130101; G08B 13/2434 20130101;
G08B 13/2431 20130101; G08B 13/2482 20130101; G06K 17/00 20130101;
G07B 15/04 20130101; G08B 21/0288 20130101; G08B 13/2462 20130101;
G08B 21/0286 20130101; G06K 7/0008 20130101; G08B 13/2477
20130101 |
Class at
Publication: |
235/385 ;
340/010.1; 340/539.13; 235/383 |
International
Class: |
G06F 017/60 |
Claims
What is claimed is:
1. A system for tracking the movement of objects in a predefined
area, said system comprising: a central controller; a readable tag
on each object to be tracked, each readable tag storing a code
identifying its corresponding object; readers at preselected
locations within said predefined area for reading the codes of said
readable tags as the objects corresponding to said readable tags
move past said readers; a communications link between said readers
and said central controller for communication of codes read by said
readers to said central controller; said controller being
programmed to collect data from said readers for tracking the
movement of objects within the predefined area.
2. A system for tracking the movement of objects as claimed in
claim 1, wherein said readable tags are radio frequency (RF)
tags.
3. A system for tracking the movement of objects as claimed in
claim 2, wherein said readable tags are passive RF tags and are
triggered by said readers to transmit their codes.
4. A system for tracking the movement of objects as claimed in
claim 2, wherein said readable tags are active RF tags.
5. A system for tracking the movement of objects as claimed in
claim 1, wherein said readers include embedded antennas.
6. A system for tracking the movement of objects as claimed in
claim 5, wherein said readers further include local controllers
connected to said antennas, said local controllers extracting codes
received by said antennas and conveying extracted codes to said
central controller.
7. A system for tracking the movement of objects as claimed in
claim 5, wherein said antennas are loop antennas.
8. A system for tracking the movement of objects as claimed in
claim 5, further comprising at least two antennas disposed in each
selected location, said central controller being programmed to
determine the direction of movement of a tagged object by analyzing
data collected from said antennas.
9. A system for tracking the movement of objects as claimed in
claim 2 and further comprising at least two RF tags disposed in
each object, said central controller being programmed to determine
the direction of movement of the object by analyzing data collected
by said readers from said at least two RF tags.
10. A system for tracking the movement of objects as claimed in
claim 1 and wherein said preselected locations within said area
correspond to transition regions between zones of said area and
wherein said central controller is programmed to determine movement
of objects from one zone to an adjacent zone by analyzing data
collected by said readers as objects traverse said transition
regions.
11. A system for tracking the movement of objects as claimed in
claim 1 and wherein said data network comprises local controllers
coupled to said readers and a communications link for transmitting
data between said local controllers and said central
controller.
12. A system for tracking the movement of objects as claimed in
claim 1 and further comprising at least one Key Track system having
a central controller, said data network connecting said readers to
said Key Track central controller for integration of data from said
readers with data from said Key Track system.
13. A system for tracking the movement of objects as claimed in
claim 12, wherein said Key Track system is configured to detect
removal and return of keys providing access to the objects.
14. A system for tracking the movement of objects as claimed in
claim 12, further comprising means for generating reports on the
movement of objects being tracked based on data from said readers
and data from said Key Track system.
15. A method of tracking the movement of an object between
predetermined zones within an area, said method comprising the
steps of: (a) establishing transition regions between the
predetermined zones; (b) detecting the object as the object
traverses a transition region; (c) identifying the object as it is
detected traversing the transition region in step (b); and (d)
determining the zone in which the object is located based upon the
detection and identification of the object in steps (b) and
(c).
16. The method of claim 1 5 and wherein step (d) includes
determining the zone in which the object is located by analyzing
information indicative of the zone in which the object was last
located and information derived from the detection and
identification of the object in steps (b) and (c).
17. The method of claim 15 and wherein step (b) comprises detecting
the direction in which the object traverses the transition region
and wherein step (d) includes determining the zone in which the
object is located by analyzing the direction in which the object
traversed the transition region.
18. The method of claim 15 and wherein step (b) comprises providing
the object with a readable tag and locating a reader in the
transition region for reading the readable tag as the object
traverses the transition region.
19. The method of claim 18 and wherein the readable tag is an RF
tag and wherein the reader includes at least one antenna for
receiving RF signals transmitted by the RF tag.
20. The method of claim 19 and further comprising providing the
object with at least two RF tags readable by the reader for
determining the direction in which the object traverses the
transition region.
21. The method of claim 20 and wherein the at least two RF tags are
spaced apart on the object to be read in sequence by the reader for
determining the direction in which the object traverses the
transition region.
22. The method of claim 20 and wherein the at least two RF tags
transmit signals at different radio frequencies for determining the
direction in which the object traverses the transition region.
23. The method of claim 19 and further comprising providing at
least two readers at the transition region for determining the
direction in which the object traverses the transition region.
24. The method of claim 23 and wherein the step of providing at
least two readers includes locating at least two antenna at the
transition region, each antenna receiving RF signals from a tag on
the object as the object traverses the transition region.
25. The method of claim 24 and wherein the at least two antenna are
spaced apart in the transition region for receiving a signal from
the RF tag on the object in sequence as the object traverses the
transition region.
26. The method of claim 25 and further comprising the step of
providing at least two RF tags on the object, the at least two RF
tags transmitting information to the at least two antenna as the
object traverses the transition region.
27. A system for tracking and controlling the movement of objects
in a predefined area comprising: a central controller; an array of
readers disposed at preselected locations in the predefined area,
said readers being in communication with said central controller; a
readable tag on each of the objects, each readable tag storing a
code identifying its corresponding object; said codes of said
readable tags being detected by said readers as objects move past
said readers and being communicated to said central controller;
said central controller being programmed to determine the location
of each object by analyzing the codes communicated by said
readers.
29. A system for tracking and controlling the movement of objects
as claimed in claim 27 and wherein said readable tags comprise RF
tags for transmitting said codes via radio frequency
transmission.
30. A system for tracking and controlling the movement of objects
as claimed in claim 29 and wherein said readers include antenna for
receiving codes transmitted by said RF tags and a local controller
for extracting the codes from received transmissions and
communicating the extracted codes to the central controller.
31. A system for tracking and controlling the movement of objects
as claimed in claim 30 and further comprising providing each object
with at least two RF tags for determining the direction in which
the objects traverse said transition regions.
32. A system for tracking and controlling the movement of objects
as claimed in claim 30 and wherein each reader includes at least
two antennae for determining the direction in which the objects
traverse said transition regions.
33. A system for tracking and controlling the movement of objects
as claimed in claim 32 and wherein each object is provided with at
least two RF tags.
34. A system for tracking and controlling the movement of objects
as claimed in claim 27 and wherein the objects are vehicles and the
predefined area is the lot of an automobile dealership.
35. A system for tracking and controlling the movement of objects
as claimed in claim 34 and further comprising a Key Track system
located at the automobile dealership, said central controller being
a part of the Key Track system and having access to information
regarding the check out and check in of keys to vehicles at the
automobile dealership.
36. A system for tracking and controlling the movement of objects
as claimed in claim 35 and wherein said central controller is
programmed to analyze information regarding the check out and check
in of keys and to integrate such information with information
communicated by said readers and to reach conclusions regarding
authorized movements of vehicles based on said analysis
37. The system of claim 36 and wherein said central controller uses
the integrated information to authorize movement of vehicles.
38. In a Key Track system for tracking the check out and check in
of keys providing access to objects, the improvement comprising
means for tracking movement of each object in the interim between
check out of the key to the object and check in of the key to the
object.
39. The improvement of claim 38 and wherein the objects are
vehicles and wherein said means for tracking movement of each
object comprises a readable tag on each vehicle and tag readers at
preselected locations within the region of-movement of the
vehicles.
40. The improvement of claim 39 and wherein said readable tags are
RF tags and said readers include antenna for receiving RF signals
transmitted by said tags as the vehicles move past said
readers.
41. The improvement of claim 40 and wherein the region of movement
of the vehicles is a lot, said lot being subdivided into
predetermined zones separated by transition regions and said
readers being disposed at said transition regions.
Description
REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of the filing date of
prior filed U.S. Provisional Patent Application Ser. No.
60/099,954, filed Sep. 11, 1998 (37 CRF 1.78(a) (4)).
TECHNICAL FIELD
[0002] This invention relates generally to object tracking and
control systems and, in a preferred embodiment, to vehicle key
tracking systems and enhancements usable with such systems for
monitoring and tracking the movement and use of vehicles accessed
by such keys.
BACKGROUND OF THE INVENTION
[0003] Many objects have intrinsic value while other objects have
value because they provide access to intrinsically valuable
objects. For instance, jewelry, coins, automobiles, sensitive
business files, and similar objects have intrinsic value
Accordingly, these items generally are secured against theft or
misuse either by locking them in vaults or storage cabinets in the
case of smaller objects, or by providing them with their own
locking and security systems such as, for example, locks and
security systems on automobiles. Keys to automobiles, storage
cabinets, file rooms, or apartment complexes are examples of
objects that have value because they provide access to
intrinsically valuable objects.
[0004] The collection of keys to automobiles at an automobile
dealership have substantial value because of the number of vehicles
to which they provide access. Accordingly, such collections of keys
have traditionally been either locked up or tracked in some way,
not only to prevent theft of vehicles but also to allow sales and
maintenance personnel to locate the keys to a vehicle quickly when
the vehicle needs to be shown, test driven, or provided with
maintenance. Tracking and control of access to these keys is
therefore of critical importance to an automobile dealership.
[0005] In the past, a variety of systems have been implemented to
track and control access to keys to vehicles in an automobile
dealership. For example, peg boards have been used to keep track of
keys as salespersons, maintenance personnel, and others remove keys
for access to vehicles. Generally, sign-out sheets have been
employed to log the check-in and check-out of such keys. Obviously,
such a manual system of tracking has numerous shortcomings due in
large part to the very real potential of human error and
forgetfulness in carrying out the sign-in and sign-out
procedures.
[0006] More recently, automated computer controlled key tracking
systems have been implemented for tracking vehicle keys at
automobile dealerships and other types of keys such as pass keys to
the apartments of apartment complexes. One such system particularly
applicable to the present invention and used widely at automobile
dealerships is the key tracking system disclosed and claimed in my
U.S. Pat. No. 5,801,628, the disclosure of which is hereby
incorporated fully by reference. In this system, referred to herein
as the "Key Track" system, keys to a vehicle are attached with a
rivet or the like to a thin plastic key tag having a depending
tongue. The tongue carries a small button-shaped electronic touch
memory device, which stores a unique code. The tongues of the key
tags are configured to be insertable in an array of slots formed in
a top panel within a storage drawer. A printed circuit backplane is
disposed beneath the array of slots and is provided with a
plurality of pairs of upstanding metal contacts, each pair of
contacts being aligned with a corresponding one of the slots. When
the tongue of a key tag is inserted in a selected one of the slots,
its touch memory device is engaged by the corresponding pair of
contacts. The Key Track system may alternatively include radio
frequency or RF tags rather than touch memory devices. In such an
embodiment, the codes stored on the tags are communicated to RF
sensors on the backplane, eliminating the need for physical
contacts.
[0007] A computer based controller is electronically coupled
through a communications buss such as a data matrix to the contacts
or sensors on the backplane and periodically polls each pair of
contacts or sensor, preferably several times per second, to
determine the presence or absence of a touch memory device or RF
tag and thus which slots in the storage drawer contain key tags and
which do not. When a slot contains a key tag, the touch memory
device of the tag is read to determine its unique code, from which
the identity of the particular key on the tag can be determined
through a table lookup. In this way, the absence or presence and
location within the storage drawer of the key tags and their
associated keys can be noted by the controller each time the array
of contacts are polled. If a tag present in a slot on a prior
polling is absent on a subsequent polling, then the controller
notes that the tag and its key have been removed from the storage
drawer. Conversely, if a key tag is detected in a previously empty
slot, the controller notes that the tag and its key have been
replaced in the storage drawer and also notes the location of the
slot in which the tag resides. The removal and replacement or
"check out" and "check in" of keys at the storage location is
therefore continuously monitored.
[0008] An access feature of the Key Track system requires an
authorized user such a salesperson needing a particular key to
enter an ID code into the controller to unlock and access the
storage drawer. The controller then informs the user of the
location within the drawer of the key tag bearing the key, or, if
the key has been checked out by another, so informs the user. When
the history of check out and check in of key tags and their keys is
combined with other available information, such as the time at
which tags are removed and replaced and the identities of the
persons who accessed the drawer and times of access, access to the
keys in the drawer can be controlled and monitored, detailed
tracking logs can be created, and queries can be made of the
controller at any time to ascertain which keys are checked out and
the identities of individuals who checked them out. This system
greatly decreases instances of lost or hoarded keys, reduces the
time required to find keys, and generally provides automatic
tracking and control of the keys, and thus, to some extent, tracks
the vehicles to which the keys provide access.
[0009] The Key Track system described above has proven extremely
valuable in the tracking and control of keys. However, the tracking
information available to the system is limited to the time that
each key is checked out, the time it is checked back in, and the
identity of the individual who accessed the key. Information about
the disposition of the key in the interim between check out and
check in, and more importantly the disposition and movements of the
vehicle or object to which the key provides access have not been
available to the Key Track system. Nevertheless, such information,
if available, could be valuable to automobile dealerships for a
variety of purposes. For example, such information, when coupled
and integrated with already available information from the basic
Key Track system, can enable compilation of statistics regarding
the average lengths of test drives, which sales personnel take
customers for test drives most often, and which test drives results
in sales. In a broader sense, the ability to monitor the movement
of vehicles accessed by checked out keys can allow dealerships to
locate vehicles on a lot simply by issuing a query to the
controller, to follow vehicle movements between designated areas or
"zones" of the lot, to confirm that when a vehicle leaves the lot,
its key has been checked out by a person authorized to take the
vehicle, and to detect theft by sensing when a vehicle attempts to
leave the lot without its key having been properly checked out. In
a similar environment, a rental car lot, the ability to monitor the
disposition of keys and movement of vehicles can prevent vehicles
from leaving the lot without having been properly leased, allows
rental vehicles to be located accurately and quickly, and deters
theft. In all these situations there is a strong interest in
tracking vehicle movements about a lot between the time when the
keys to the vehicle are checked out and when they are checked back
in and in determining when vehicles leave and when they return to
the lot.
[0010] Thus, a need exists for a method and apparatus and an
enhancement to the basic Key Track system to enable the system to
track not only the check out and check in of keys, but also the
interim movements of vehicles to which the keys provide access. It
is to the provision of such a method and apparatus that the present
invention is primarily directed.
SUMMARY OF THE INVENTION
[0011] Briefly and broadly described, the present invention
comprises a system for tracking the movement of objects in a
predefined area. The system includes a central computer or
microprocessor based controller and a readable tag on each of the
objects to be tracked. Preferably, the readable tags are radio
frequency (RF) tags, which store unique codes identifying their
corresponding objects and transmit their codes when appropriately
activated. Readers, which preferably comprise RF sensors or
antennas connected to local controller/receivers, are positioned at
preselected locations within the predefined area for reading the
codes of the-readable tags as objects bearing the tags move past
the readers. The preselected locations can correspond to transition
regions between designated zones of the area within which the
objects are to be tracked. Communication links connect the local
controllers to the central controller. The central controller is
programmed to collect data from the local controllers and to issue
instructions to the local controllers for monitoring, tracking, and
controlling the movement of objects within the predefined area.
[0012] A more specific and preferred embodiment of the invention,
and the embodiment that forms the context within which the
invention is described herein and that is considered the best mode
of practicing the invention, comprises enhancements and
improvements to the Key Track system disclosed in my U.S. Pat. No.
5,801,628 to adapt the system for use in tracking and controlling
the movement of vehicles at an automobile dealership. It should be
understood, however, that even though the invention is described in
the context of such an embodiment for clarity, many other
applications and embodiments, some of which are discussed in more
detail below, are possible and all such applications and
embodiments should be considered to be within the scope of the
invention.
[0013] In the preferred embodiment, vehicles at a dealership are
each provided with one or more RF tags and the dealership lot is
organized into a number of logical zones, such as the service area,
fueling area, areas outside lot exits, and the like. Tag readers
are located at the transition regions between the zones and each
tag reader includes a local controller and one or more antennas or
other appropriate sensors, preferably embedded within the pavement
at the transition regions. The local controllers are connected
through communications links to the central Key Track system
controller, which also monitors and controls access to keys to the
vehicles as previously described. The communications links can be
one of many possible types of data links including, for example,
RS232 lines, ethernet links, or parallel or serial communications
busses.
[0014] As vehicles are moved from one zone of the lot to another,
they pass the tag readers at the transition regions, where the RF
tags of the vehicles are activated to transmit their unique codes,
which are received by the local controllers and conveyed to the
central controller. The central controller can thus determine the
movement of each vehicle about the lot as well as movement of
vehicles off of and onto the lot through the lot exit. This
information is combined with information maintained by the Key
Track system about the disposition of the keys to each vehicle,
such as the identity of the person who checked out the keys, to
provide substantially improved and enhanced monitoring and control
of vehicle movement. For example, if a vehicle approaches the exit
to leave the lot, the central controller is able to determine
whether the individual who checked out the keys has authority to
remove the vehicle from the lot. If so, a gate can be opened and if
not appropriate alarms can be generated. Further, and even more
significantly, the system provides automatic day time security
against theft without the need for gates or other physical
barriers. More specifically, if a vehicle is detected by a reader
and its key has not been checked out, then a theft is indicated and
appropriate alarms or remedial actions can be taken. In addition to
authorizing vehicle movement and providing security, useful data
such as the length of test drives, maintenance histories, fuel
usage, and the like becomes readily available to the dealership
through the present invention and can be used to improve procedures
and ultimately provide better service to the customer.
[0015] Many other embodiments and implementations of the present
invention are possible, both within the context of an automobile
dealership and otherwise. For example, the invention can be
implemented with advantageous results in an automobile rental lot
or any place where vehicles or, indeed, any mobile objects need to
be tracked. Placement of two reader antennas in close proximity
and/or two RF tags on a vehicle enhances the ability to determine
the transition of a vehicle from one zone to another and provides
built in system redundancies. If desired, the monitored zones
within a parking lot can be as small as one parking space so that
the precise location of each vehicle in the lot can be
determined.
[0016] Other applications and embodiments of the invention include
controlling access to and tracking the movement of sensitive or
confidential files within a file room, tracking the check out and
movement of expensive tools at a work site, the tracking and
control of access to evidence in a court's evidence room, and other
applications where tracking the movement of and controlling access
to objects is desirable.
[0017] Thus, a method and system is now provided that enhances the
Key Track system by adding the capability not only to log check out
and check in of keys, but also to monitor and collect information
about and authorize the movement of vehicles corresponding to the
keys. The collected information is transmitted to the Key Track
controller where it is combined and strategically integrated with
existing information about the disposition of keys to provide
valuable reports and to control ingress and egress to the lot or
between various zones of the lot. The combined information can be
used for other purposes, such as scheduling and tracking
maintenance schedules where vehicles naturally move from one zone
to the next as part of the maintenance process. In a broader sense,
monitoring and control of access to and movement of many types of
portable objects is possible with this invention. These and other
applications, features, objects, and advantages of the invention
will become more apparent upon review of the detailed description
set forth below taken in conjunction with the accompanying drawing
figures, which are briefly described as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a simplified diagramatic sketch of an automotive
dealership subdivided into zones and illustrating the present
invention in a preferred embodiment thereof.
[0019] FIG. 2 is a perspective illustration of a zonal transition
region within an automotive dealership showing the embedded
antennae and local controller of the tag reader.
[0020] FIG. 3 is a perspective view illustrating application of the
present invention to control operation of a fueling station in an
automotive dealership.
[0021] FIG. 4 is a perspective view illustrating application of the
present invention to monitor and control ingress and egress at an
automotive dealership.
[0022] FIG. 5 is a perspective view illustrating the approach of a
vehicle equipped with RF tags at a transition region between zones
of an automobile dealership.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] As mentioned above, the invention is described herein within
the context of tracking movements of vehicles within an automobile
dealership and specifically the strategic integration of such
tracking with an existing Key Track system, which is described in
detail in the incorporated disclosure of U.S. Pat. No. 5,801,628.
Many other applications and embodiments are possible and some are
described in more detail below. Further, the system and method of
this invention makes use of a variety of electronic components such
as RF tags and RF tag readers. In general, the construction and
operation of such components is beyond the scope of the present
invention and will not be described in detail. However, such
components are commercially available and their use and electronic
interconnections is generally known to those of skill in the art.
For example, Radio Frequency Identification (RFID) products,
including RF tags and readers are available from Texas Instruments,
Inc., which markets both paper tags under the trade name "Tagit"
and glass capsule tags. SCS, Inc. markets RFID products under
various trade names including DuraLabel and Trolleyponder and
licenses the technology of these devices. Other companies including
Phillips and AEG also offer RFID products. Many of these
commercially available products are suitable for application in the
present invention.
[0024] While a detailed description of RFID hardware and techniques
is not necessary, a general overview is helpful. Most commercially
available RF tags and reading systems rely on low frequency
magnetic field coupling for communication. RF tag readers in many
instances include a multi turn loop antenna with a large number of
loops to maximize the magnitude of the magnetic flux generated by
the antenna and thus its range. Other types of antennae are
possible including capacitively coupled antennas, dipole antennas,
and the like. Many RF tags are passive devices that store a unique
code and are powered by capturing a fraction of the energy radiated
by the reader's antenna when the tag is in the vicinity of the
antenna. More specifically, RF tags typically consist of a small
antenna coupled to an integrated circuit chip, which includes a
memory for storing an ID code and perhaps other information and
controlling mechanisms for transmitting the code to be received by
the reader's antenna. These passive tags include power regulation
hardware to capture a fraction of the incident power from the
reader's antenna and to charge a capacitor, which acts as a local
battery. The power-on/reset circuitry causes the integrated circuit
to activate and begin operation when operational power levels are
sufficient.
[0025] Once energized and activated, the RF tag communicates with
the reader by modulating the induced radio frequency currents with
the unique ID code. The reader, in turn, includes demodulation
circuitry, which interprets the received modulations to extract the
code. In this way, the unique code stored in the RF tag is
transmitted to the reader. The reader can then convey this code
through an appropriate communications link (for example a parallel
or serial communications buss, RS 232 link, ethernet link, wireless
communications link, and the like) to a remote controller or
computer. Active RF tags are also available commercially as
alternatives to passive tags. Generally, these tags have an on
board power source and many are able to receive and store data as
well as to communicate data to a reader, as do passive tags.
Typical frequencies of operation of RF tags range from as low as
125 KHz to 13.56 MHz and to as high as 2.4 GHz, although other
frequencies are possible. It should be noted that whereas the term
"radio frequency" is considered by some to include only the portion
of the electromagnetic spectrum between 9000 Hz and 3000 GHz, this
term, as used and intended in the present disclosure, is meant to
include any appropriate portion of the electromagnetic spectrum
whether within or outside this range.
[0026] With this background in mind, reference will now be made in
more detail to the drawings, in which like numerals refer to like
parts throughout the several views. FIG. I is a diagramatical plan
view of an automotive dealership 11 having a showroom 12 surrounded
by a paved lot 13. The lot 13 is partitioned into a number of
discrete areas referred to herein as zones with each zone
representing a region of the lot where vehicles may be located from
time to time. Zone 1, for example may be a parking area of the lot
where vehicles are displayed for sale. Zone 2 may be an additional
parking area or perhaps a fueling or washing area while Zone 3 may
be a service staging area and Zone 4 a service facility. Obviously,
a lot may be subdivided into more or fewer zones than those
illustrated in FIG. 1 and the zones may correspond to any number of
types of regions where vehicles may be located. Also, Zone 5 may be
considered to be the region outside the lot and off the premises of
the dealership. The various zones of the lot 13 are separated by
transition regions, designated by the capital letter T in FIG.
1.
[0027] A Key Track system 21 as disclosed in U.S. Pat. No.
5,801,628 is located in the showroom 12 of the dealership 11. In
general, the Key Track system comprises one or more storage drawers
22 for storing keys and from which keys may be checked out and
checked back in. A computer or microprocessor based central
controller 23 is coupled to the storage drawer 22 as described in
said patent. In general, the controller 23 receives requests from
users for keys, opens the drawer 22 if the request is from an
authorized user, and logs when keys are removed from and returned
to the storage drawer.
[0028] An RF tag reader is located at each transition region T
separating the various zones of the lot. For example, RF tag reader
28 is located in the transition region T from Zone 2 to Zone 1,
reader 33 is located in the transition region T from Zone 1 to Zone
2, reader 38 is located in the transition region between Zones 2
and 3, Reader 43 is located in the transition region between Zones
3 and 4, and reader 49 is located in the transition region, which
is the lot exit, between Zones 1 and 5, outside the lot. RF tag
reader 28 comprises a pair of loop antennas 29 and 31 respectively,
which preferably are buried in the pavement of the lot in the
transition region T. Alternatively, the antennas can be located in
vertical upstanding pylons or in an overhead structure, but burial
beneath the pavement is preferred and is considered to be the best
mode of practicing the invention because the antenna is more
secure, more tamper resistant, and hidden from view.
[0029] The loop antennas 29 and 31 are connected to a local
controller 32, which is configured to energize the antennas, to
transmit and receive modulated radio frequency signals therefrom,
and to demodulate received signals to extract data, such as
identifying codes, received by the antennas. Similarly, reader 33
includes buried loop antennas 34 and 36 connected to local
controller 37, reader 38 includes buried loop antennas 39 and 41
connected to a local controller 42, reader 43 includes loop
antennas 44 and 46 connected to local controller 47, and reader 48
includes buried loop antennas 49 and 51 connected to local
controller 52.
[0030] The local controllers 32, 37, 42, 47, and 52 are
electronically coupled through appropriate communications links,
generally indicated by dashed lines and the reference numeral 56,
to the central controller 23 of the Key Track system 21. As
mentioned above, the communications links can be any of a number of
connections appropriate for bidirectional communication between the
local controllers and the central controller 23. Data transmission
links, protocols, and techniques are well know to those of skill in
the art and need not be described in detail here. A more detailed
description of one type of data transmission technique that may be
applicable to this invention is disclosed in the incorporated
disclosure of U.S. Pat. No. 5,801,628. By means of the
communications links 56, the various local controllers are able to
transmit data and information to the central controller 23 and the
central controller 23 can transmit data and information to the
local controllers.
[0031] A vehicle, generally indicated at 24, is shown on the lot 13
and is arbitrarily located in Zone 1 of the lot. While only one
vehicle is illustrated in FIG. 1 for clarity, it will be understood
that a dealership may house dozens or hundreds of vehicles and that
the present invention applies equally to large numbers of vehicles
on the lot. The vehicle 24 is provided with one or more, and
preferably a pair, of RF tags referred to with the reference
numerals 26 and 27 in FIG. 1. RF tag 26 is attached to the front of
the vehicle while RF tag 27 is attached to the rear of the vehicle.
Several physical locations for attaching the RF tags are
envisioned. In general, locations that offer easy installation of
tags, that are not obvious to the casual viewer, and that make it
difficult to remove the tags are desirable. Potential locations
include on plastic wheel wells inside the engine compartment, on
fiberglass bumpers or other non-metal body parts, or embedded
within rubber tires. In general, RF tags need to be placed on
non-metallic surfaces; however, at least one manufacturer of RF
tags reports tag functionality in close proximity to metal surfaces
such as steel I-beams.
[0032] The system illustrated in FIG. 1 may be configured to carry
out the method of the present invention, in one embodiment thereof,
as described below. It should be understood that while each
transition region T in FIG. 1 is illustrated with a pair of buried
antennas and the vehicle is illustrated with a pair of RF tags, the
invention also contemplates the use of a single antenna at each
transition zone and/or a single RF tag on each vehicle or any
combination thereof. These various configurations are described in
more detail below.
[0033] When a salesperson or other authorized user desires to
access a vehicle on the lot for purposes, for example, of a test
drive, maintenance, cleaning, etc., the Key Track system 21 is used
as described in U.S. Pat. No. 5,801,628 to retrieve the key to the
vehicle. In general, the user enters his or her identification
number into the central controller 23 and identifies the vehicle
for which access is desired. If the user is authorized to have
access to the vehicle, the Key Track system unlocks the storage
drawer 22 and indicates to the user which slot within the drawer
the key is located. The user then takes the key, whereupon the
central controller 21 notes the time the key was taken and the
identity of the user who took it.
[0034] The user then uses the key to access the vehicle 249 As the
vehicle is driven about or off of the lot 13, the readers in the
various transition regions detect movement of the vehicle past each
transition region by receiving the unique code of the is vehicle
from the PF tag or tags 26 and 27 on the vehicle. This information
is transmitted via the communications links 56 back to the central
controller 21. The central controller may use the information to
make a variety of decisions each time movement of the vehicle past
a transition zone is detected. For example, if the user is a member
of the maintenance crew, that user may be authorized to move the
vehicle only within the bounds of the lot 13 and into Zone 4 for
maintenance. In this event, if the central controller receives the
vehicles identification code from local controller 52 at the exit
portal 50, a decision may be made that the user who checked out the
key to the vehicle is not authorized to remove the vehicle from the
lot. The central controller may then generate appropriate alarms
and/or send instructions back to the local controller 52 via the
communications link 56 instructing it not to open the exit gate. In
this way, users not authorized to remove vehicles from the lot are
prevented from doing so. The system also is uniquely suited to
provide automatic security without gates. For example, if a vehicle
is detected approaching an exit and the Key Track system determines
that the key to the vehicle has not been checked out of the Key
Track system, then a possible theft can be considered to be in
progress and alarms can be sounded, a signal can be sent to the RF
tag on the vehicle to disable the vehicle, etc. Thus, theft of
vehicles on the lot is virtually eliminated.
[0035] If the user stays within the lot, the central controller
receives data from the local controllers as the vehicle passes each
transition zone. The central controller can then create logs of
vehicle movement from zone to zone, locate the vehicle in a
particular zone if its whereabouts in desired, and create reports
useful to the dealership such as, for example, maintenance
schedules, times required for maintenance, etc. When the user
finishes with the vehicle, the key is returned to the Key Track
system 21, which notes that the key has been checked back in and
its location within the storage drawer
[0036] In another example, a salesperson may retrieve a key from
the Key Track system to access a vehicle for a test drive. Since
this user is authorized to remove the vehicle from the lot,
detection of the vehicle approaching the exit portal 50 will result
in an instruction from the central controller to open the gate to
allow the vehicle to be removed from the lot If there is no gate at
the exit, which usually is the case, the vehicle will simply be
allowed to exit without an alarm being generated. When the vehicle
returns, it is again detected entering the exit portal and this
information is transmitted via the communications link 56 to the
central controller 23. From information such as this, the central
controller can track the whereabouts of the vehicle, compile useful
reports regarding, for example, average lengths of test drives for
each salesperson, ratios of sales to number of test drives for
salespersons, and the like, and provide security against
unauthorized use or theft.
[0037] Some specific examples of applications of the present
invention in the context of an automotive dealership will be
described in more detail with reference to FIGS. 2 through 5. In
general, however, it will be seen that the method and system of
this invention allows tracking not only of the check out and check
in of keys to vehicles, but also of the movement of vehicles about
and off of the lot. A substantially enhanced level of tracking,
control, and security is therefore possible. The zone in which each
vehicle resides on the lot is known by the central controller at
all times and this information can be conveyed to a user when a key
is checked out so that the vehicle can be located quickly on the
lot.
[0038] Further, while the zonal transition approach can be applied
on a macro scale as indicated in FIG. 1 wherein several vehicles
can be located in a zone, it also can be applied on a micro scale
or a combination of macro and micro scales if desired. In a micro
configuration of the invention, zones can be defined such that each
zone can contain only one vehicle. For example, micro zones might
be defined as individual parking spaces on the dealership lot with
each parking space being provided with its own RF tag reader. The
readers at each micro zone are be in continuous communication with
vehicles located in the various parking spaces and transmit this
information to the central controller. In this way, the precise
location of vehicles can be determined as well as detailed logs of
when vehicles are removed from parking spaces, when and in which
parking space they are returned, and their movements about or off
of the lot in the interim. In this regard, a micro zonal
configuration of the invention is in some respects an extension of
the Key Track system itself wherein the objects being tracked are
keys rather than vehicles and each micro zone corresponds to a slot
in the storage drawer. Any combination of micro and macro zones can
be established.
[0039] The antennae, sometimes called the sensors, of the RF
readers most preferably are controlled by their respective local
controllers, which also may be embedded or buried beneath the
surface, instead of being connected directly through a "dumb" local
interface to the central controller. The control functionality is
distributed to the local level to insure continued functionality if
the data link to the central controller of the Key Track system is
disrupted. Further, the local controller is better able to sense
tampering with the reader system. For example, if an antenna of a
reader is cut or disconnected, the resultant change in impedance
can be detected easily by the local controller whereas the central
controller connected through a dumb interface likely would only see
no signals from the antenna and the system would be vulnerable to
defeat by tampering.
[0040] In a configuration where active two way RF tags are attached
to vehicles, smart local controllers can send data and information
to the active RF tags. This allows a local controller whose link to
the central controller may be disrupted to attempt to transmit data
by "piggybacking" on RF tags; i.e., storing information for the
central controller on an RF tag for being conveyed to the central
controller when the tag is encountered by a subsequent reader. In
addition, active RF tags make possible an embodiment of the
invention wherein ID markers are positioned in the lot at various
locations and are "read" by the active tags as vehicles carrying
the tags pass over the markers in moving about the lot. The RF tags
themselves are then responsible for transmitting location
information directly via radio frequency transmission to the
central controller. In a broader sense, the use of RF tags that can
receive and store information gives rise to the possibility of a
"virtual network" wherein information can be transmitted to and
stored on the ID tags themselves for reading at a later time by
another reader at another location. Service history, for example,
might be stored and automatically read each time a vehicle is
presented at a service center for maintenance or service.
[0041] Since the local controller in the preferred embodiment is in
real-time communication with RF tags passing its antenna, it can
send information to the tags, the central controller, and/or
directly to activate ancillary equipment such as, for example,
security devices and alarms and video and/or audio capturing
equipment. This is a powerful attribute of the present invention.
For example, if a series of captured video frames of vehicles
traversing a portal are OCR processed, the license plate of
vehicles with inoperable or no RF tags can be noted (presumably
some other sensor such as a laser beam indicating a portal
transition would alert the central controller, which would
determine that a vehicle traversed the portal but no signal was
received from an RF tag). Cross linking to license plate databases
to note potential prospects who were not helped by a sales
professional would provide extremely useful information to the
dealership. Accordingly, it will be seen that the potential to
monitor and adjust the day-to-day operation of the dealership can
be enhanced significantly through application of the present
invention.
[0042] FIG. 2 illustrates in more detail a transition region T
between two zones, Zone 1 and Zone 2, within a dealership parking
lot. Preferably, but not necessarily, the transition region T is
bordered by curbs or other barriers 61 to force vehicles to
traverse the transition region T at the proper location. A pair of
spaced apart loop antennas 63 and 64 are embedded or buried within
the pavement 62 at the transition zone T. The antennae are
connected by appropriate cabling 66 and 67 respectively to a local
controller 68, which also may be buried if desired. The local
controller 68, in turn, is connected via the communications link 56
to the central controller 23, which preferably is part of a Key
Track system.
[0043] As a vehicle bearing one or more RF tags moves from Zone 1
to Zone 2, it traverses the transition region T and passes over the
antennae 63 and 64. The RF tag is activated by and, in the case of
a passive tag, draws power from the field generated by the antennae
and transmits its unique code, which is detected by the antennae,
demodulated by the local controller 68, and conveyed via
communications link 56 to the central controller for processing.
The central controller then interprets the data to determine that
the vehicle corresponding to the code is passing from Zone 1 to
Zone 2. Movement of vehicles from zone to zone is thus tracked and
monitored. FIG. 2 illustrates the tag reader with a pair of spaced
antennae or sensors buried in the pavement. While this is a
preferred configuration for purposes of system robustness, as
detailed below, a single antenna may also be used with similar,
albeit less robust, results.
[0044] FIG. 3 illustrates a particular application of the system
and method of the invention applied to a fueling station at an
automobile dealership. A fueling pump 73 is stationed by a curb 71
for delivering fuel to vehicles. A pair of antennas 74 and 76 are
embedded within the pavement 72 adjacent the pump 73. The antennae
are connected via appropriate cabling 77 and 78 respectively to a
local controller 79 which is coupled through communications link 81
to central controller 23. The pump 73 is provided with a pump
controller 82, which includes a switch for activating the pump and
may also include circuitry for capturing information from the pump
such as, for example, the amount of fuel pumped at a filling, and
conveying this information back to the local controller 79 for
transmission to the central controller 23. When a vehicle
approaches the fuel pump 73 for fueling, the unique code of its RF
tag is captured and transmitted by the local controller to the
central controller. The central controller then checks its Key
Track logs to confirm that the user who checked out the keys to the
vehicle is authorized to fuel the vehicle. If not, the central
controller may transmit an instruction to the local controller not
to activate the pump and may also generate appropriate alarms to
indicate an inappropriate fueling attempt.
[0045] If the user is authorized to fuel the vehicle, the central
controller may issue instructions to the local controller to
activate the pump, whereupon a signal is sent from the local
controller to the pump controller to allow the pump to be operated.
When fueling is complete, the pump controller may convey to the
local controller information regarding the amount of fuel used and
this information is conveyed back to the central controller.
Alternatively, the initial instruction to the pump controller may
be to pump only a predetermined amount of fuel. Thus, unauthorized
fueling is prevented and fuel usage can be monitored and controlled
on an individual vehicle level to insure the most efficient use of
fuel in the daily operation of the dealership. Preferably, the two
antennae adjacent to the pump are spaced such that each must
receive a code from a respective RF tag on the vehicle to authorize
pumping. This ensures that the vehicle is properly positioned for
fueling and prevents fraud by, for example, stationing one vehicle
with one of its RF tags over an antenna while backing an
unauthorized vehicle up to the pump for illicit fueling.
[0046] FIG. 4 illustrates application of the invention at an exit
portal of the dealership lot to monitor and control the comings and
goings of vehicles from the lot. The exit portal is bordered by
curbs 89 and an antenna 91 is embedded within the pavement 92 of
the portal. The antenna is connected by cabling 93 to the local
controller 94, which is coupled through communications link 96 to
the central Key Track controller 23. The local controller is also
connected by cabling 97 to a gate control 88, which can be
activated to raise and lower a gate 87 to allow or prevent a
vehicle from passing through the exit 86. The local controller 94
may also be connected to receive information from a key pad 101,
which can be conveniently located on a key pad pedestal 98. In
operation, as a vehicle approaches the exit, the unique code of its
RF tag is transmitted to the local controller 94 and conveyed to
the central controller 23. The central controller consults its Key
Track logs to determine the identity of the user who checked out
keys to the vehicle. If the user is not authorized to remove the
vehicle from the lot, the central controller may generate
appropriate alarms and convey instructions to the local controller
not to open gate, thereby preventing unauthorized removal of the
vehicle from the lot. If the user is authorized to remove the
vehicle from the lot, the central controller may transmit
instructions to the local controller to open the gate, whereupon an
appropriate instruction is transmitted to the gate control 88 to
open the gate 87 and allow the vehicle to leave the lot.
[0047] The user may also be required to enter a PIN number into the
key pad as a final confirmation that the vehicle is properly being
removed from the lot. The PIN number is communicated to the local
controller via cabling 99 and, possibly, on to the central
controller 23. Only if it is determined that the vehicle is
authorized to leave the lot, that the person who checked out the
keys is authorized to take the vehicle off the lot, and the
appropriate PIN number is entered will the gate be opened.
Accordingly, in the event, for example, that a would be thief
disables a salesman and attempts to remove a vehicle from the lot,
the thief will not be able to drive the vehicle off the lot because
the appropriate PIN number will not be entered. Such a system may
also be used in other situations such as, for example, at the exits
from an apartment complex to prevent vehicles of tenants from being
stolen by requiring both a proper identification of the vehicle
through its RF tag and the proper PIN number before a gate is
opened.
[0048] FIG. 5 will now be referenced as the foundation of a
discussion of the various configurations of readers and RF tags and
the advantages of each configuration. FIG. 5 illustrates a
transition region T disposed between two adjoining zones, Zone 1
and Zone 2, on the lot of an automobile dealership. A pair of
spaced apart antennas 108 and 109 are embedded within the pavement
107 in the transition region T and each is connected by cabling 111
and 112 respectively to a local controller 113. The local
controller 113 is coupled through communications link 114 to a
central Key Track controller 23. A vehicle 116, indicated generally
by phantom lines for clarity, is seen approaching the transition
region T in direction 124 from Zone 1 toward Zone 2. The vehicle
116 is provided with a forward RF tag 117, which includes an
antenna 118 connected to an integrated circuit chip 119 containing
the encoding, decoding, control, and memory circuits of the RF tag.
A rear RF tag 121 is provided at the back of the vehicle and
includes an antenna 122 connected to an integrated circuit chip
123. The RF tags are shown very much larger than their typical
actual size for clarity of illustration. In reality, RF tags can be
as small as a postage stamp or even smaller and are easily attached
and hidden on the vehicle. In the case of smaller tags, the reader
antenna can be larger to maintain operating range.
[0049] FIG. 5 shows a reader with two embedded antennae and two RF
tags on the vehicle. However, the invention contemplates multiple
variations and combinations of reader antennae and RF tags
including a single reader antenna and single RF tag, double reader
antennae and a single RF tag, and the double reader antenna double
RF tag configuration illustrated in FIG. 5. The simplest of these
configurations is a single reader antenna and a single RF tag on
the vehicle. With such a configuration, as the vehicle moves from
one zone to an adjacent zone, it is confined to pass through the
transition region T and over the reader antenna embedded in the
pavement thereof. As the RF tag on the vehicle enters the field
created by the reader antenna, it is activated by the field and
transmits its unique code as described above and the code is
received by the reader antenna and ultimately conveyed to the
central controller. The RF tag may also accept and store
information, which can be read by other readers on site or at
another location. For example, RF tags might store information
regarding the history of a vehicle's progress through the
manufacturing plant, shipping channels, dealerships, and ultimately
to a customer.
[0050] Since only a single reader antenna and a single RF tag is
used, the central controller's vehicle tracking routines must rely
on past history data to extrapolate and update the location of the
vehicle. More specifically, since the last logged location of the
vehicle (FIG. 5) is known to be in Zone 1, and since it is now
being detected in the transition region T separating Zone 1 and
Zone 2, a conclusion may be made that the vehicle can now be
considered to be in Zone 2 until again detected at a transition
region. While such a system is relatively simple, it lacks a degree
of rigor that is desired in many situations. For example, if the
history data is corrupt and the vehicle is not in reality in the
region that the central controller thinks it is, then an inaccurate
conclusion as to the new location of the vehicle may be made or an
error condition may be generated. Error conditions may also be
created if, for example, a vehicle begins to pass through a
transition region and then is reversed and backed into its original
Zone.
[0051] It can thus be seen that while the single reader/single tag
configuration may be useful in some situations, it can be subject
to mistakes and errors that may not always be acceptable. One
reason that errors nay be generated is because, with a single
reader and a single tag, no information is available to the system
regarding the direction in which the vehicle is traversing the
transition region. Only the location of the vehicle at the
transition can be determined.
[0052] A more rigorous configuration of the invention is realized
by the use of two spaced reader antennas embedded in the pavement
at the transition region and a single RF tag attached to a vehicle.
As the vehicle traverses the transition region, the first reader
antenna encounters and activates the RF tag and reads its unique
code, which is conveyed to the central controller. At this point,
the second reader antenna cannot read the transmitted code because
of the physical separation of the reader antennas. Eventually, the
RF tag moves with the vehicle out of the range of the first reader
antenna and enters the range of the second reader antenna. The RF
tag is energized a second time by the second antenna and transmits
its unique code, which is received by the second antenna.
[0053] It will thus be seen that the local controller first
receives the code from its first reader antenna and then receives
the code from its second reader antenna. With this information, the
central controller (or the local controller for that matter) can
safely conclude that since the vehicle traversed the transition
region in a direction from the first reader antenna toward the
second reader antenna, the vehicle moved from Zone 1 into Zone 2.
Since no reliance is made on knowledge of where the vehicle was
located prior to its traversal of the transition region, a two
reader antenna/one RF tag configuration provides more rigor and is
less susceptible to error and inaccurate location that the single
reader antenna/single RF tag configuration. In fact, since the new
Zone-and-transition region traversed are safely known, if the
location history data base is corrupted or contains data
inconsistent with this determination, an error or suspicious
condition can be flagged. A log of such suspicious conditions can
then be examined by key personnel to determine if a pattern
suggests that a particular reader is faulty or someone has tampered
with the readers or RF tags. Thus, this configuration is
substantially more reliable than the simple one reader/one RF tag
configuration.
[0054] Another more rigorous configuration of the invention is the
one reader antenna/two RF tag configuration wherein two RF tags are
placed on each vehicle and one reader antenna is embedded in a
transition zone. Such an arrangement is feasible for use with
vehicles since a typical car or truck is relatively large and the
RF tags can be spaced apart a distance larger, and preferably at
least twice as large, as the operating range of the reader
antennae. With such a configuration, as a vehicle traverses a
transition region, the RF tag on the front end of the vehicle
encounters the reader antenna and transmits its code followed by
the RF tag on the rear of the vehicle. The local controller, or
alternatively the central controller, can access its data base to
identify the vehicle provided with the codes of the two RF tags and
which of the two codes corresponded to the forward RF tag and which
to the rear RF tag.
[0055] Thus, the direction of traversal of the transition region is
reliably determined from the encounter. If the vehicle stops in the
transition region and reverses course, either only 1 of the tags is
read or the first tag's code is received twice with the second tag
being read only once or not at all. From this information, the
activity of the vehicle in the transition region can be determined.
However, in such a situation, since the direction of traversal is
not obtainable from the data, previous zone information still is
needed to extrapolate the zone in which the vehicle is now
considered to be located. While periodic database inventory checks
can mitigate the potential uncertainties of relying on previous
zone information, the potential for errors still exists.
[0056] The most rigorous configuration of the invention is the two
reader antenna/two RF tag configuration illustrated in FIG. 5. Such
a configuration eliminates reliance on previous zone information
and also provides a level of redundancy that enhances the
reliability of the system. For example, consider when a vehicle
traverses a transition region T between Zone 1 to Zone 2. As the
vehicle moves through the transition region, the first reader
antenna interrogates the first RF tag and then the second RF tag.
The second reader antenna also interrogates the first and then the
second RF tag, although this pair of interrogations occur later in
time than the interrogations by the first reader antenna. The local
and/or the central controller can then determine, based on various
combinations of this data, that a particular vehicle passed in a
particular direction into a Zone adjacent to the transition region.
Thus, the precise zonal location of each vehicle can be known at
all times.
[0057] Further, because more data is collected than the minimum
required, the extra data provides a level of redundancy. For
example, of one reader antenna malfunctions, the local controller
can process the received information as if the system were
configured as a two RF tag/one antenna system as discussed above.
Similarly, if one of the RF tags malfunctions, the local controller
can process the information as in a one RF tag/two reader antenna
configuration. Finally, if both a reader antenna and an RF tag
malfunctions, then the data can be processed as if the system were
configured in a one reader antenna/one RF tag system. Such
redundancy allows the local controller to continue to track zonal
transitions and update the position database with different levels
of confidence and also allows for the detection and logging of
system malfunctions observed during each traversal of a transition
region by a tagged vehicle. Defective RF tags can be flagged for
replacement and faulty readers flagged for periodic
maintenance.
[0058] In addition to providing direction of traversal information,
a configuration incorporating two reader antennae can also estimate
the speed at which the vehicle traversed the transition zone or
passed the reader. Such information can be helpful in controlling
speeding within a lot or other designated area.
[0059] Instead of requiring a relatively large physical separation
between RF tags in multiple RF tag configurations, the two RF tags
can alternatively be selected to operate at different radio
frequencies. This allows the RF tags to be located closer together
than the range of the reader antenna to a large degree. However, a
key to a dual RF tag approach is the exploitation of the order in
which the RF tags are encountered to determine direction of travel.
Therefore, in multiple frequency systems, the area of non-overlap
must remain large enough to allow sufficient communication time
before the overlap region is encountered. In reality, the size of
the non-overlap region does not need to be very large because RF
tag technology allows RF tags to be interrogated in much less that
0.1 second. Obviously, the size of the region of non-overlap is
determined to some degree by the speed-at which vehicles traverse
transition regions, but in a dealership situation, these speeds
tend to be relatively low and do not present an obstacle to close
placement of the RF tags on vehicles.
[0060] Also, communication strategies exist that allow two closely
spaced RF tags operating on the same frequency and both within a
reader antenna's range to be interrogated. These communication
strategies allow the readers to communicate with multiple RF tags
in their range of operation. Generally, these strategies require
one reader antenna to be designated master and the other the slave.
Only one antenna, the master, issues a request for RF tags to relay
codes to both receiving antennas (master and slave).
[0061] The invention has been described herein within the context
of the tracking and control of keys and vehicles at an automobile
dealership. While this is a preferred embodiment of the invention
and represents what is considered to be the best mode of carrying
out the invention, the invention is far from limited to such a
context and has a wide variety of applications outside automotive
dealerships. For example, there exists a critical need within
certain organizations such as classified government installations,
hospitals, and the like to control access to and tracking of the
location of confidential or classified files. The present invention
can be applied to these situations to, for example, prevent
classified files from being removed from specified locations by
persons not authorized to remove them. Here, the files themselves
are provided with RF tags and correspond to the vehicles of the
preferred embodiment and the designated rooms (file rooms, review
areas, and the like) correspond to the various zones. Locking doors
controllable by the central controller preferably are provided at
the transitions between rooms and only unlocked if an individual
attempting to move a file from one room to another has authority to
do so.
[0062] Another application is the tracking of personnel in
automotive dealerships or otherwise. In such a scenario, an arm
band might contain an RF tag. Readers located at key doorways
and/or key locations interrogate the tags of personnel moving
through the doorways to track the location of personnel at all
times. Personnel passing through certain designated doorways, e.g.
sensitive area entrances or exits, might activate appropriate
alarms.
[0063] Similarly, children in schools can be tracked by issuing ID
badges bearing RF tags to each child and adult. The passage of
individuals through key portals is detected by readers located at
these portals. Secondary sensors note the passage of individuals
and if no RF tag is read, then alarms can be generated to indicate
that a non-badged individual passed through the portal.
[0064] Factories have problems with workers clocking in and then
not going to their assigned work areas. Worker ID badges bearing RF
tags and readers at portals to work areas can be employed to track
workers and insure that they are at their designated stations.
These and other applications of the object tracking and control
system of this invention are possible and all are envisioned to be
within the scope of the invention as set forth in the claims.
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