Abstract:
A system and method is disclosed for a shopping system, the system including a shopping cart including a plurality of wheels; a portable electronic device (e.g., a CST or POS terminal), coupled to the shopping cart, for displaying shopping data; and a position mapping system, coupled to the electronic device, for developing a shopper location relative to a start location, the mapping system including a distance measuring system, coupled to one of the plurality of wheels; for providing a distance signal indicating a distance of movement of the shopping cart; and a direction measuring system for providing a direction signal concurrent with the distance signal. Another embodiment is a shopper tracking system including a shopping cart having a plurality of wheels; a portable electronic device, coupled to the shopping cart, for displaying shopping data; and an energy generator, coupled to one of the plurality of wheels, for adding energy to a power source of the portable electronic device. The shopper tracking method includes the steps of measuring a net distance traveled by a shopping cart and measuring direction information concurrently with the distance information to produce a relative location that is offset from a known location and converting the relative location to an absolute coordinate by providing absolute coordinates for the known location.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to shopper tracking systems, and more specifically to a shopper tracking system for retrofit addition to an existing shopping location having reduced infrastructure improvement requirements. 
     BACKGROUND OF THE INVENTION 
     It is known to provide shopper-tracking systems to use in locating a shopper within a shopping location. Shopper tracking systems typically employ portable electronic devices such as, for example, customer service terminals (CSTs) or portable point-of-sale (POS) terminals that display sales and marketing information to the shopper, and may in some cases allow the user to tabulate and purchase items without passing through a stationary checkout location. 
     There are many advantages to knowing a shopper&#39;s current location as well as the path that the shopper walked in reaching the particular location. Among these advantages are special retail options available to the shopper near the current location may be easily presented on the portable device, and directions may be provided the shopper for moving to a desired product&#39;s location when the shopper&#39;s present location is known. 
     Shopper-tracking systems that rely on triangulation with various beacons installed throughout the shopping establishment to pinpoint a shopper&#39;s location do exist. Such systems require an infrastructure investment to install and maintain the multitude of beacons. Other systems locate a shopper by use of a universal product code (UPC) scanner incorporated into the portable device. When the shopper scans the UPC barcode, the system locates the shopper in the shopping establishment where such products are available for selection. Such a system cannot track a precise shopping path taken by the user, and it does not know the shopper&#39;s location absent the user scanning a UPC code. 
     Accordingly, what is needed is a method and system for easily tracking a shopper&#39;s current location as the shopper moves through a store without requiring installation of wireless location systems for triangulation or constant scanning of merchandise. The present invention addresses such a need. 
     SUMMARY OF THE INVENTION 
     A system and method is disclosed for a shopping system, the system including a shopping cart including a plurality of wheels; a portable electronic device (e.g., a CST or POS terminal), coupled to the shopping cart, for displaying shopping data; and a position mapping system, coupled to the electronic device, for developing a shopper location relative to a start location, the mapping system including a distance measuring system, coupled to one of the plurality of wheels; for providing a distance signal indicating a distance of movement of the shopping cart; and a direction measuring system for providing a direction signal concurrent with the distance signal. Another embodiment is a shopper tracking system including a shopping cart having a plurality of wheels; a portable electronic device, coupled to the shopping cart, for displaying shopping data; and an energy generator, coupled to one of the plurality of wheels, for adding energy to a power source of the portable electronic device. The shopper tracking method includes the steps of measuring a net distance traveled by a shopping cart and measuring direction information concurrently with the distance information to produce a relative location that is offset from a known location and converting the relative location to an absolute coordinate by providing absolute coordinates for the known location. 
     The present invention tracks a shopper&#39;s current location as the shopper moves about a store without requiring installation of wireless location systems for triangulation or constant scanning of merchandise that the shopper passes during the shopping trip. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic block diagram of a preferred embodiment for a shopper tracking system; 
         FIG. 2  is a process flowchart of the preferred embodiment for the shopper tracking system; and 
         FIG. 3  is a generic block diagram of a portable electronic device of the type that may be used as described in FIGS.  1 - 2 . 
     
    
    
     DETAILED DESCRIPTION 
     The present invention relates to tracking a shopper&#39;s current location as the shopper moves about a store without requiring installation of wireless location systems for triangulation or constant scanning of merchandise, and in some implementations providing a recharging platform for a portable electronic device, such as for example a customer service terminal (CST) or a portable point-of-sale (POS) terminal. The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements. Various modifications to the preferred embodiment and the generic principles and features described herein will be readily apparent to those skilled in the art. Thus, the present invention is not intended to be limited to the embodiment shown but is to be accorded the widest scope consistent with the principles and features described herein. 
     In the sales environment, systems and applications are being developed to permit a customer to carry a portable electronic device with them as they walk through an establishment. To simplify the following discussion, a preferred type of portable electronic device (the CST) will be specifically referred to, though the present invention may be used with many types of portable electronic devices having the functions described below. The CST may provide sales or marketing information to the customer as they move about the establishment. An internal battery that requires periodic recharging typically powers the CST. It is part of the preferred embodiment to adapt the shopper tracking system to include a recharging function for such devices when they are being used. 
       FIG. 1  is a schematic block diagram of a preferred embodiment for a shopper tracking system  100 . System  100  includes a portable electronic device  105  engaged with a cradle  110  coupled to a generator  115  driven by a wheel  120  of a shopping cart  125 . Additionally, system  100  may also include a communications system  130  coupled to a computing system  135  having a merchandise database  140 , computing system  135  operable in response to instructions stored on a non-volatile removable medium, represented by disk  145 . A merchandise reader  150 , coupled to cradle  110  reads merchandise identification information used to access database  140 . 
     Device  105  of the preferred embodiment is a special purpose computing platform having a microprocessor or microcontroller coupled to memory, input/output (I/O) devices, direct memory access, timers and other supporting hardware, firmware, and software to determine and display appropriate information to a shopper and to implement the particular functions for the shopper and the retail establishment. There are many general purpose and special purpose devices available that could be modified for use in the present invention, as well as new devices that are introduced into the marketplace. For example, customer service terminals (CSTs), personal digital assistants (PDAs), tablet PCs, webpads, portable point-of-sale (POS) terminals may all be suitable for use as device  105 . Device  105  includes a compass function, either embedded or available as an added function, for producing a direction signal for use by device  105  as further described herein. Additionally, electronic device  105  typically includes one or more batteries for powering its operation and functions. 
     Cradle  110  is a docking cradle for device  105  and exchanging power and signals between other components of system  100  and device  105 . In some implementations, device  105  may be permanently engaged with cradle  110 , or removably coupled. In some embodiments, some of the features of the present invention may be unavailable while device  105  is removed from cradle  110 . 
     Generator  115  of the preferred embodiment provides both power for recharging rechargeable batteries of device  105 , and a net movement distance signal to device  105  through cradle  110 . The distance signal is a composite of the number of whole or partial rotations of wheel  120  and the direction of those rotations. By knowing the circumference of wheel  120 , device  105  is able to know the net distance cart  125  has moved from one calculation cycle to another. 
     Device  105  combines the distance signal with the concurrently available direction signal from the compass function to track a series of path vectors of cart  125  as a shopper moves about the retail establishment. The total of these path vectors define a shopper&#39;s relative location at each moment, the location being relative to various origins of the path vector components. Device  105  of the preferred embodiment includes a calibration function to map a beginning origin path vector component of the series of path vectors to an absolute location. This in turn allows device  105  to determine a shopper&#39;s absolute location at any time, with the series of path vectors defining the shopper&#39;s path. Additionally, as the shopper moves throughout the store, generator  115  continually recharges the batteries of device  105  extending the time that each device  105  may be used. 
     Reader  150  and computing system  135  are used to help refine the shopper&#39;s location indicated by the path vector calculations. The user may periodically scan merchandise to retrieve merchandise identification information as part of the normal shopping/marketing/sales function of device  105 . For example, reader  150  may be a bar code reader for reading universal product code (UPC) information available on many grocery store products. Other types of sales locations may use different types of merchandise identification information, possibly requiring use of a different type of reader  150 . 
     This scanning may be done for obtaining price, nutrition information or other data about the product, for example. Device  105  is able to query database  140  by transmitting the UPC to computing system  135  using wireless transmission system  130  (e.g., radio frequency, ultrasonic or infrared communications) and receive absolute coordinates for the scanned product. Device  105  may update the calculated location using the product location information to more accurately position the shopper. To account for mis-shelved products, device  105  may ignore product location information having too large of a distance delta from the calculated location. 
       FIG. 2  is a flowchart of the preferred embodiment for a process  200  of the shopper tracking system  100 . Process  200  determines a system&#39;s starting location at step  205 . Step  205  establishes an absolute starting location for a particular system  100  by, for example, scanning an item with a known absolute location. Thereafter, process  200  waits at node  210  for information that may be used to update the system&#39;s present location. 
     Process  200  responds, in the preferred embodiment, to two types of location updating data: movement of system  100  and absolute location updating data. In response to an update indication, or expiration of a timer, process  200  advances to step  215  from node  210  to test whether system  100  has moved. If the test is negative, process  200  advances to step  220  to test whether location-updating data may be available. If the test at step  220  is negative, process  200  returns to node  210  to wait for a next event. 
     When the test at step  215  is positive, indicating movement of cart  125 , process  200  advances to step  225  to measure a net wheel rotation. Generator  115  provides both an indication of the direction of wheel rotation, and the number of whole or partial rotations in the particular direction. The information may be provided over a data channel separate from the power channel, or the data may be superimposed on the power signal. At step  225 , process  200  determines the net number of whole or partial rotations of wheel  120 . Next, process  200  at step  230  converts the rotation information into a distance. The conversion may be done by knowing/calculating the circumference of wheel  120 . This number is the magnitude of a path vector component for movement of cart  125 . 
     Next at step  235 , process  200  measures the direction cart  125  is pointing when the distance signal from step  225  and step  230  is being generated. The cart direction signal is preferably an output from the compass function included as part of device  105 . In some embodiments, two or more encoders included in wheels of cart  125  may be compared to provide the cart direction signal. In some embodiments, one or more wheels of cart  125  are pivotally coupled to the cart and could provide a cart direction signal to device  105  through cradle  110 . The cart direction signal is the direction information for the path vector component. 
     After generating the distance signal at step  230  and the cart direction signal at step  235 , process  200  advances to step  240  to update the shopper&#39;s delta distance location using the path vector component produced from the direction signal and the distance signal. The end point of the path vector component, when added to the previous path vector component, relatively locates the shopper in the shopping center. 
     After step  240 , process  200  calculates the shopper&#39;s current absolute location at step  245  by applying a known absolute coordinate to the origin of the initial path vector component (the known absolute coordinate is available from step  205  in the preferred embodiment). 
     Device  105  of the preferred embodiment has a calibration feature to enter the absolute coordinates of one of the origins of the path vector components. For example, when a shopper passes over a certain landmark, the shopper could activate a button associated with that landmark to assign a predetermined absolute location to the origin of one of the path vectors. Thereafter, knowing the relative movement from the landmark, and knowing the absolute location of the landmark positively locates absolute coordinates for the shopper. After step  245 , process  200  goes to step  220 . Step  220  is also reached when the test at step  215  is negative, meaning the cart has not moved. 
     Step  220  determines when a bar code is scanned and reader  150  is active. When the test at step  220  is positive, process  200  advances to step  250  from step  220 . 
     Step  250  uses reader  150  to obtain merchandise identification information, in this case the UPC. Next, process  200  advances to step  255  to obtain absolute coordinate information for the identified merchandise. System  100  does this by using computer system  135  to query database  140  using the UPC and retrieving the absolute location of the identified merchandise. Process  200  tests the absolute location of the identified merchandise against the calculated location available using the current summation of the location vector components. In step  260 , process  200  determines whether the calculated location is physically close (e.g., within some predetermined threshold) to absolute location data for the merchandise. If the test at step  260  is not close, process  200  does not update the calculated location with the merchandise absolute location and returns to node  210 . For example, for a product that is not shelved in the proper location, the UPC may indicate a wrong location for the user, so system  105  rejects adjustments that exceed a predetermined threshold. 
     When the test at step  260  determines that the calculated location is physically close to the merchandise absolute location, process  200  at step  265  updates the calculated location using the absolute location for the read merchandise. 
     In some stores, computing system  135  may return a range of possible locations for the product and device  105  must discriminate among the data, or adjust the shopper only when the calculated location is within the proper range. In some implementations, device  105  may also transmit the calculated location and computing system  135  may return corrected information. In this embodiment, when device  105  has a unique identifier, computing system  135  may track and record the user&#39;s location rather than having device  105  store the entire path record. After step  265 , process  200  returns to node  210  to monitor for possible changes to the shopper&#39;s location as described above. As long as the user is scanning, process  200  cycles through steps  220 - 265  for each scanned product. 
       FIG. 3  is a generic schematic diagram of device  105  of the type that may be used as described in  FIGS. 1-2 . Device  105  includes a central processing unit  305  that interfaces to memory  310 , a display  315 , a Bluetooth module  320 , a bus interface  325  and a power management module  330 . CPU  305  controls the operation of device  105  under instructions stored in memory  310  to implement process  200  as described above. 
     CPU  305  monitors power status from power management module  330 , with power management module  330  controlling the state of a display backlight  335  and monitoring a status of a battery  340  through a bus (e.g., SMBus  345 ). CPU  305  controls operation of power management  330  and sends/receives data and/or control signals to other peripherals by use of a register file  350  coupled to bus interface  325 . Register file  350  is additionally coupled to power management  330 , bus  345 , a universal asynchronous receiver-transmitter (UART)  355 , and a peripheral interface  360  for interfacing information to CPU  305 . 
     UART  355  is coupled to a RS-232 transceiver  365  that is coupled in turn to a docking cradle connector  370  included as part of cradle  110  shown in FIG.  1 . Docking cradle  370  is also coupled to battery  340  when recharging is desired. 
     Peripheral interface  360  may be a serial peripheral interface or an inter-integrated circuit (I2C), for example, to interface to a touchscreen  375 , an analog-digital converter (ADC)  380 , or a keypad  385 . In some applications, a compass  390  coupled to ADC  380  is used as described above, and device  105  uses a wireless network interface  395  to communicate to computing system  135 . 
     The components of device  105  are but one example of a suitable configuration, with CPU  305  controlling operation and receiving information based upon instructions in memory  310 . Memory  310  may be removable, and is preferably non-volatile. Other configurations of the components, or additional components may be used to configure a suitable device  105  to implement process  200 . 
     In device  105 , the distance signal is provided through docking cradle connector  370  and associated with the proper direction signal from compass  390 . It is one feature of the present invention that device  105  may deactivate backlight  335  using power management module  330  during periods when the distance signal is below a particular threshold to conserve battery power. As also described above, compass function  390  may not be available internally, as direction data may be provided through cradle connector  370 . Further, Bluetooth module  320  may provide broadcasts that may directly, or indirectly, provide location update information when passing close enough to the station without requiring the shopper to actively scan a product, or without installing extensive location systems throughout the shopping establishment. 
     Although the present invention has been described in accordance with the embodiments shown, one of ordinary skill in the art will readily recognize that there could be variations to the embodiments and those variations would be within the spirit and scope of the present invention. Accordingly, many modifications may be made by one of ordinary skill in the art without departing from the spirit and scope of the appended claims.