Note: Descriptions are shown in the official language in which they were submitted.
CA 02476968 2004-08-10
SYSTEM AND METHOD FOR NOTIFYING A CASHIER OF THE PRESENCE OF
AN ITEM IN AN OBSCURED AREA OF A SHOPPING CART
[0001] The present invention relates generally to an improved system and
method for
notifying a cashier if an item is present in an obscured area of a shopping
cart.
BACKGROUND OF THE INVENTION.
[0002] Bottom of Buggy (BOB) is a common grocery and general retail industry
term.
BOB is a key phrase that retail managers use to express their desire for
cashiers to pay
close attentions to a bottom storage area of shopping carts in order to spot
items that need
to be processed through the cash register or other point of sales terminal.
[0003] Point of sales terminals are known in the art and need not be described
in great
detail. Generally speaking, they comprise a software package operating a
collection of
hardware devices including a keyboard, monitor, barcode scanner, weight scale,
and
electric payment terminal device. The point of sale terminal reads in objects,
usually by
barcode or unique identification number and optionally by weight, as they are
presented
to a cashier and keeps a running tatal payable far purchased products.
[0004] The bottom storage area of the shopping cart refers to a flat storage
area, typically
just above the wheels, which runs the length of the shopping cart and is
located
underneath the main package storage area. This area is a concern for retail
managers
because it is often obscured from the cashier's view. Therefore, iterr~s
placed on the
bottom of the cart may be missed by the cashier and losses may be incurred by
a store.
[0005] Losses through missed items on the bottom of the cart can occur for a
number of
different reasons. The customer may forget that there is an item on the bottom
of the
shopping cart and either is never aware that the item has not been properly
processed
through the store's Point Of Sale system or decades not to return to the store
once they are
aware of the unprocessed items.
[0006] Alternately, an unscrupulous customer may attempt to hide the existence
of items
located on the bottom of the buggy. This can be accomplished in many different
fashions, including: covering the bottom of the main package storage area with
a flyer or
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CA 02476968 2004-08-10
articles of clothing so as to shield the bottom of the buggy from the
cashier's view;
placing articles of clothing over top of items located on the bottom of the
shopping cart,
concealing the items underneath; pushing the shopping cart through t:he
checkout aisle
quickly enough so as not to give the cashier time or opportunity to check the
bottom of
the shopping cart.
[000'1] Yet further, some cashiers may be negligent in their duty to practice
due diligence
in checking for items in the bottom of the shopping cart. Worse yet,
unscrupulous
cashiers may act in coercion with customers known to them personally and
purposely not
process items placed on the bottom of the shopping cart, in effect defrauding
the retailer.
This is often referred to as a form of "sweet hearting".
[0008] The retail industry, most notably the retail grocery industry, has long
suffered
these types of losses despite the several inventions designed to reduce them.
For
example, U.S. Patent No. 5,485,006 issued to Allen describes a detection
mechanism that
uses photodetectors to detect the presence of objects located on the lower
storage section
of a shopping cart as it moves past a checkout station, an audio and/or video
alarm for
alerting the cashier to the detected object, and a video camera for recording
a video image
of the object that was detected. Allen discloses that once the alarm state is
entered, the
cash register draw is commanded to close, thereby preventing any further
transactions.
The alarm state remains until nullified by depressing a push-button at the
checkout
station. However, locking the cash register typically occurs after the
customer has been
checked out. Therefore, the cashier may not notice that there is an it~;,m on
the lower
storage cart until it is too late. The cashier would then have to ring the
items in
separately which is time consuming and tedious for both the cashier and
customer.
[0009] Another example of a prior art attempt to solve this problem is
described by U.S.
Application No. 2003/0184440, filed by Ballantyne. The application describes
an item
detection apparatus that uses an optical line generator, an area-imaging
sensor, and a
pattern analyzer to determine the presence or absence of items on the bottom
tray of a
cart as it moves through a checkout aisle. The pattern-recognition algorithm
used by the
pattern analyzer determines a differential image process to remove the impact
of ambient
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CA 02476968 2004-08-10
lighting on the analysis. If an item is detected on the bottom tray of the
cart, an audible
alarm may be triggered and a secondary system, such as a wheel brake, may be
activated
that physically prevents further movement of the cart through the checkout
aisle. Similar
to the previous solution, the cashier may not notice that there is an item on
the lower
storage cart until it is too late. The cashier would then have to ring the
items in
separately which is time consuming and tedious for both the cashier and
customer.
(0010] Further, Canadian Patent No. 2,283,382 issued to Ballantyne describes
an
inspection apparatus that uses a sensor for detecting the presence of a
shopping, a video
camera for capturing an image of the lower portion of the shopping cart, and
an image
display for displaying the image to the cashier. If the presence of a shopping
cart is
detected, the image of the lower portion of the shopping cart is displayed on
the image
display. The image display remains until the cash register drawer is closed.
The present
solution simply displays the bottom of the buggy to the cashier while the
transaction is
taking place. Typically, however, as the cashiers hecome accustomed to the
display, they
will begin to pay less attention to it, reducing its effect.
(0011] Yet another example of prior art attempt to solve this problem is
described by
U.S. Patent No. 5,883,968 issued to Welch. The patent describes a fraud-
detection
system that uses a colour video camera to identify the items that are
contained in a
shopping cart. The system uses a colour-normalization technique to improve the
accuracy of the item identification process. The system also takes an overhead
image of
the checkout station and the adjacent cart aisle to determine whether the
shopping cart is
empty. If, at the end of the transaction, the shopping cart is found to be not
empty, the
system determines whether the transaction involved the purchase of any items
that are
considered to be too large to be placed on the take-away belt of the checkout
station. An
"event" is generated if the shopping cart is found to be not empty, but the
transaction
record contains no "large" items: However, the patent does not explain the
ramifications
of such an event being generated.
[0012] Accordingly, even with such a proliferation of solutions, Bottom Of
Buggy
product detectors have achieved only a very limited success in the marketplace
since
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CA 02476968 2004-08-10
there has been a continuing need for improvement. Accordingly, it is an object
of the
present invention to obviate or mitigate at least some of the aforementioned
disadvantages.
SUMMARY OF THE INVENTION
[0013) In accordance with an aspect of the present invention there is provided
a method
of facilitating a checkout at a shopping cart checkout station, comprising the
steps of:
inhibiting processing of items on the shopping cart in, the event of a
detection of a non-
empty obscured section of the shopping cart; and processing the items upon
receipt of a
command input from an operator at the checkout station.
[0014] In accordance with a further aspect of the present invention, there is
provided a
shopping cart checkout station, comprising: detector for detecting a non-empty
obscured
section of a shopping cart, the detector being configured to generate a halt
command
upon the detection of the non-empty obscured section; and computer processor
for
processing items on the shopping cart for checkout, the processor being in
communication with the detector and being configured to inhibit the processing
of the
items on the shopping cart upon receipt of the halt command from the detector.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] An embodiment of the present invention will now be described by way of
example only with reference to the following drawings in which:
24 Figure 1 is a top view of a checkout counter;
Figure 2 is a side view of the checkout counter shown in Figure 1;
Figure 3 is a side view of a shopping cart barcode scanner;
Figure 4 is a front view of the shopping cart barcode scanner shown in Figure
3; and
Figure 5 is a flow chart illustrating operation of the checkout counter in
accordance
with an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] For convenience, like numerals in the description refer to like
structures in the
drawings. Referring to Figure l, an overhead view of a checkout station (or
counter) is
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CA 02476968 2004-08-10
illustrated generally by numeral 100. The checkout counter 100 comprises an
entry
counter or conveyor belt 102, a combination weight scale/barcode scanner 104,
a
keyboard 106, a cashier display monitor 108, an exit counter or conveyor belt
110, a
bagging area 112, a customer display monitor 114, a handheld barcode scanner
116 and a
cashier workspace 118.
[0017) Typically, customer traffic flows as indicated by arrow 101 in Figure
1, as each
customer passes through a cashier lane. The general process is described as
follows. The
customer removes their products from the shopping cart and places them on the
entry
counter or moving conveyor belt 102.
(0018] The cashier is then responsible for passing all items past the
combination weight
scale/barcode scanner 104 for scanning or weighing the items as required. This
operation
is typically part of the Point Of Sale system and under control of the point
of sale
software. The handheld barcode scanner 116, which is also part of the Point Of
Sale
system provides the cashier with the ability to scan barcoded items that are
too big to be
passed through the combination weight scale/scanner 104. The handheld barcode
scanner
116 is typically on a cord long enough for the cashier to reach over the
counter 100 and
access the product.
(0019] Further, the cashier may need to enter information for non-barcoded
items, such
as produce for example. Accordingly, the cashier uses the keyboard 106 to
enter their
Product Look Up (PLU) numbers. The keyboard 106 is also used for entering
miscellaneous Point Of Sale information such as tender amounts.
(0020] While the cashier is checking out the customer's products, information
is
displayed to the cashier on the cashier display monitor 108. The cashier
display monitor
108 is typically a Point Of Sale computer monitor aimed at the cashier, for
displaying
various items of information about the current transaction, such as a list of
items akeady
checked out and a running total of dollar amount of the transaction. The same
or similar
information is displayed to the customer on the customer display monitor 114.
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CA 02476968 2004-08-10
[0021] After the cashier has processed a product through the point o:f sale
system, the
cashier typically places the product on the exit counter or conveyor belt 110.
The
products are moved into the bagging area 112, where they are placed into bags
by one or
more of the cashier, the customer, or a bagging clerk.
S [0022] Although the above description illustrates a typical checkout process
at a typical
checkout counter, various modifications can be implemented. For example,
instead of
providing both a cashier display monitor 108 and a customer display monitor
114, a
single display monitor may perform both functions. Further, the bagging
process may
differ in that the cashier places the products into bags before placing them
onto the exit
counter 110. In this case the bagging area 112 may not be necessary. Yet
further, the
handheld barcode reader 116 may be cordless, or may not be provided at all.
These and
other modifications will be apparent to a person of ordinary skill in the art.
[0023] Refernng to Figure 2, a side view of the checkout counter 100
illustrated in
Figure 1 is shown. As seen from this perspective, the checkout counter 100
further
includes a camera housing 202, a camera view port 204, and a shopping cart
barcode
reader 206.
[0024] The camera housing 202 is used to house a camera (not shown). The
camera
model used in the present embodiment is the Logitech 4000 Pro web camera. The
Logitech camera is a slightly higher end web camera and other cameras such as
the
Creative PD1130 would likely function equally as well. The camera housing 202
is used
both for protecting the camera from physical harm, as well as protecting it
from having
its angle of view altered after installation. In the present embodiment, the
camera
housing 202 is bolted down to a rear vertical surface under the checkout
counter 100.
[0025] The camera housing 202 includes the camera view port 204, which is
basically a
hole facing out towards the area whereby the shopping cart will pass. The
camera is
positioned such that its lens aims out of the camera view port 204. The camera
view port
204 may also be covered by a clear material such as glass or plastic in order
to protect the
camera's lens.
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CA 02476968 2004-08-10
[0026] The shopping cart barcode reader 206 comprises a laser beam barcode
reader and
is mounted so that the laser beam, which scans the barcodes, is in a generally
vertical
configuration. The laser beam is directed towards the area through which the
shopping
cart will pass for reading a barcode affixed to the shopping cart.
[0027] The camera housing 202 and the shopping cart barcode reader 206 are
spaced
apart such when the shopping cart barcode reader 206 detects a barcode on the
shopping
cart, the lower level storage area of the shopping cart will be positioned in
from of the
camera.
[0028] Referring to Figure 3, a side view of the shopping cart barcode reader
206 is
shown. In the present embodiment, the shopping cart barcode reader 206
comprises a
scanner 302, a laser beam 304, and a cord assembly 306. The cord assembly
includes a
power cable and a communications cable. The cord assembly 306 leads into an
interfaceljunction box, which splits the power and communications into two
separate
cables. The cord assembly 306 exits from the rear of the scanner 302 and is
typically
attached to the checkout counter to avoid causing problems.
[0029] As can be seen from the drawing, the laser beam is emitted from the
scanner 302
towards the cashier aisle through which the shopping cart will be passing.
Referring to
Figure 4 a front view of the shopping cart barcode reader is shown. In this
figure the
laser beam 304 being emitted from the barcode scanner is aimed directly at the
viewer.
[0030] All shopping carts in the store are affixed with a barcode. The barcode
is placed
on the cart such that it can be scanned by the shopping cart barcode reader
206. In the
present embodiment, the barcode is placed on the lower storage level of the
shopping
cart. Further, it is preferable that the location of the barcode for shopping
carts of similar
size and shape is similar.
[0031] The actual barcodes affixed to the shopping cart can vary depending on
the
implementation. For example, all shopping carts may share a common barcodes or
each
shopping cart may have a unique barcode. In the present embodiment, the
shopping carts
have unique barcodes comprising a common five-digit prefitx.
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CA 02476968 2004-08-10
[0032] Referring to Figure 5, the checkout process in accordance with the
present
embodiment is illustrated generally by numeral 500. In step 501, the shopping
cart
barcode scanner 206 scans for a shopping cart baxcode to pass in front of it.
Once a
barcode is detected, the process proceeds to step 502 where several tests are,
optionally,
performed on the barcode to verify the presence of a shopping cart. These
tests are
described as follows.
[0033] The barcode may be verified to ensure that the prefix of the shopping
cart barcode
matches the predefined common prefix assigned to all shopping carts. Further,
the
barcode may be checked to ensure that it differs from the previously scanned
shopping
cart barcode. This reduces any adverse effects of the same shopping cart being
moved
back and forth in front of the scanner during the same transaction. Duplicate
entries may
be checked by control logic cantained in the scanner itself, or the software
used to
implement the checkout process. If either of these tests fails, the process
returns to step
501, otherwise it continues to step 504.
[0034] When the barcode is detected the process proceeds to step 504,. In step
504, the
camera takes a picture of the lower storage area of the shopping cart and
captures the
image. Once again, the placement of the camera in relation to the shopping
cart barcode
scanner 206 and the barcode affixed to the shopping cart result in the camera
taking the
picture as soon as the barcode is detected.
[0035] The process then proceeds to step 506, wherein the captured image is
processed to
determine whether or not a product is present on the lower storage areav of
the cart. The
image processing is performed a,s follows. A predefined region is spf;cified
within the
camera's view area for analysis. Typically, this is the region in which the
product would
be located. Anything in the captured image appearing outside of this region is
ignored
for the purposes of image analysis.
[0036] The image is converted to a saturated, 256 grayscale image to assist
with the
image processing. Although the image is captured in colour, the image
processing is
performed in grayscale for increasing the processing accuracy. When an image
is
converted into saturated grayscale, details such as textures and patterns. are
washed out,
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CA 02476968 2004-08-10
while edges are emphasized. This allows features such as the wire grating of
the
shopping cart itself or the lines of tile on a floor, to be practicavlly
ignored when
comparing images, so items on the bottom of the cart are emphasized. It also
reduces the
effects of varying light conditions.
[0037] The converted image is compared against a stored image, also a
saturated 256
grayscale image, of an empty shopping cart. The stored image is not
necessarily stored
as a saturated grayscale image, but may be converted from a colour image
during a
system startup routine. The differences between the images are analysed using
a Mean
Square Error formula. Although other image comparison algorithms may also be
used
effectively, this method protects the process from varying light conditions
that are
common throughout the day in a retail store where outside lighting affects the
quality and
hue of the light indoors. 'The image processing used in the present embodiment
is
provided Intrepid Control Systeys. The Mean Square Error algorithm is applied
to the
captured and stored images to determine whether or not an item exists within
the
predefined region.
[0038] In step 508, once the comparison has been made, the process determines
whether
or not an item was detected on the lower storage area of the cart. If no item
was detected,
the process returns to step 502 and waits for the next shopping cart.
[0039] If an item was detected, the process continues to step 512, where the
cashier is
notified of existence of an item on the bottom of the shopping cart. In the
present
embodiment the cashier is notified via a popup window that displays an image
of the
item, captured by the camera, on the cashiers display screen 108.
[0040] Further, in addition to displaying an image of the item, the Point; Of
Sale terminal
is halted. Accordingly, the cashier is prevented from any further processing
of the
transaction, including scanning items or tendering the sale, until that
notification screen is
acknowledged by the cashier.
[0041] In the present embodiment, operation of the point of sale terminal is
halted as
follows. When the notification screen is sent to the cashier, a "PostMessage"
Windows~
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CA 02476968 2004-08-10
API call is made to the point of sale terminal with the following parameters
to deactivate
the scanning equipment: the parameter "wParam" is set to 1; the parameter
"msg" is set
to a unique id obtained through the Windows~ API call "RegisterWindowMessage";
and
the parameter "lPararn" is set to a pointer addressing the barcode of the
shopping cart. In
this manner, not only in the transaction halted, but the point of sale
terminal is updated
with the barcode ofthe corresponding shopping cart.
[0042] In step 514, the process pauses until the cashier provides
acknowledgement of the
existence of items on the bottom of the shopping cart. In the present
embodiment, this is
achieved by pressing a predefined key on the keyboard 106.
[0043] Once the key has been pressed, the process continues to step 516 in
which the
point of sale terminal is allowed to proceed as normal. In the present
embodiment, the
point of sale terminal is reactivated using a second "PostMessage" Windows~
API call
with the following parameters: the parameter "wParam" is set to 0; the
parameter "msg"
is set to a unique identifier obtained through the Windows~ API call
"RegisterWindowMessage"; and the parameter "lParam" is set to null.
[0044) If the cashier determined that the item on the bottom storage area of
the shopping
cart was not a product sold by the store, for example the customer's purse,
the cashier can
continue to scan the remaining items, if any. Alternately, if the cashier
determined that
the item on the bottom storage area of the shopping cart was product sold by
the store, the
cashier can scan the product and then continue to scan the remaining items, if
any.
[0045) For the present embodiment, the software required to implement the
process is
stored on the point of sale Terminal, but is separate from the point of savle
software. This
provides flexibility to integrate the process with various types of point of
sales terminals.
[0046] Accordingly, it can be seen that the present embodiment provides a
store manager
with a tool for alerting cashiers to potential products stores in the lower
level storage area
of a shopping cart. The method forces the cashier to take note of the lower
level storage
area of a shopping cart if an items is detected, and allows the cashier to
easily include the
product in the transaction.
CA 02476968 2004-08-10
[0047] In an alternate embodiment, further control is exercised by the store
manager by
providing a central computer for monitoring all of the point of sale
terminals. In the
present embodiment, all the point of sale terminals are connected via, a
network to the
central computer. As described in the previous embodiment, the bottom storage
area of
the shopping cart is scanned for items. When an item is detected, in addition
to
displaying the item image to the cashier, the item image is communicated from
the point
of sale terminal to the central computer. In addition to the item image, other
information
may be transmitted as well, including the date, time, a point of sale terminal
identifier, a
cashier identifier, shopping cart barcode, a list of items checked out, and
the like.
[0048) Depending on the implementation, shopping cart barcodes can be linked
to the
transaction by one of the following two methods. In a first method, the
barcode scanned
by the shopping cart barcode scanner 206 is sent to the Point Of Sale terminal
to be
stored, along with the transaction, in the Point Of Sale database.
[0049] In a second method, the shopping cart includes an additional copy of
the barcode
on an upper portion of the cart. The cashier can then scan the additional
barcode, using
the handheld scanner 116, which is connected to and controlled by the Point Of
Sale
terminal.
[0050] Accordingly, it can be seen that storing a list of items checked out
along with the
picture of the bottom of the cart for later review by a store manager will
likely discourage
cashiers from attempting to ignore, purposefully or otherwise, detection of
items on the
lower storage area of the shopping cart.
[0051) Further, the shopping cart serial numbers can be shown on customer
transaction
receipts a,s well as stored in Point Of Sale historical databases on the
central computer for
later review. This indicates to the customer that the retailer has technology
in place to
safe guard against unpaid items, which are placed on the bottom of the
shopping cart,
leaving the store. Additionally, the customer display monitor 114 may be
configured to
display a notice to the customers indicating that this type of technology is
in place. Such
warnings may deter some customers from trying to sneak products through the
checkout
counter.
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[0052] Additionally, having a record of the shopping cart serial numbers
provides a
digital record for the retailer to identify which shopping cart left the
building with which
customer. Such information would be valuable where once missing carts are
retrieved
throughout the neighborhood and returned to the retailer.
[0053] Therefore, it can be seen that the central computer provides valuable
statistical
information tracking all shopping cart movement, and making all images
available for
analysis. Further it can be seen that by recording point of sale transaction
information
along with an item's image, and forcing a cashier to acknowledge these
transactions by
interrupting a point of sale terminal's operation, a store manager has a tool
to hold
cashiers accountable for products placed on the bottom of shoppin~; carts that
move
through their checkout station.
[0054] Additionally, having a record of shopping cart traffic as they :move
through the
cashier stations, regardless of an item detected or not, allows the store
manager to
monitor the health of their shopping cart inventory. Furthermore, head office
personnel
are presented with a tool that may assist in transferring shopping cart
inventory out of one
store and into another. For example, if the cart traffic data shows that 20
percent of the
carts get used 80 percent of the 'time, it may indicate that there is an
excess of shopping
carts at a particular location. This provides the store with an opportunity to
save money
by transferring carts to a different store location that is in need, instead
of ordering new
carts. Likewise, if the reverse were true, it would indicate that there is a
shortage of
shopping carts.
[0055] Yet further, cart traffic data may also indicate problem carts. If a
cart has not been
pushed through a cashier station for quite some time, typically well below the
store
average rate, it may indicate a caa~t is in need of repair.
[0056] Although the previous embodiments have been described as detecting
items
stored on the lower storage area of the cart, the present invention is not
limited as such.
Rather, the invention can be equally applied to another area that may be
obscured from
the cashier's view, as will be appreciated by a person of ordinary skill in.
the art.
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[0057] While the invention has been described in connection with a specific
embodiment
and in a specific use, various modifications will occur to those skilled in
the art without
departing from the spirit of the invention.
[0058] The terms and expressions which have been employed in the specification
are
used as terms of description and not of limitations, there is no intention in
the use of such
terms and expressions to exclude any equivalents of the features shown and
described or
portions thereof, but it is recognized that various modifications are possible
within the
scope of the invention. The present invention is intended to be defined
according to the
following claims and their equivalents.
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