# Patent

## Title
Method and apparatus for use in a vending machine

## Abstract

During operation of a vending machine, an image is obtained of an area of interest in the vending machine. As a product selected by a customer moves toward a product retrieval location, images of the area of interest are obtained and transmitted to the data base. Images in the data base are compared to determine whether or not the selected product has moved to the area of interest.

## Background
BACKGROUND OF THE INVENTION
The present invention relates to a new and improved method and apparatus for use in a vending machine which dispenses products to customers.
Vending machines have been utilized to provide various snacks, beverages and other products to customers. The vending machines dispense selected products to customers in response to insertion of money, which may be paper and/or coins, into the machines. Known vending machines may be similar to vending machines disclosed in U.S. Pat. Nos. 5,303,844 and 6,732,014.
These known vending machines are periodically stocked with products which are to be dispensed to customers. During stocking, the products are positioned in dispensing devices. Each of the dispensing devices holds a plurality of products which are sequentially moved from storage locations to a dispensing location. Customer readable indicia indicates the location of the product associated with each of the dispensing devices.
When a customer has selected a product, the customer inserts money or a credit card into the known machine. In addition, the customer actuates a selection switch panel to indicate the location of the product which has been selected. When this has occurred, a dispensing device for the selected product is operated and the selected product moves from a dispensing location to a product retrieval location. The customer manually retrieves the product at the product retrieval location.
Known dispensing devices have included one or more helical conveyors. These conveyors have sequentially moved products from storage locations to dispensing locations. Other dispensing devices have utilized other types of conveyors, for example, dividers or pusher members may be connected with a conveyor belt or chain and moved with the belt or chain to sequentially move products from storage locations to a dispensing location. Other known dispensing devices use gravity feed of products.
After a vending machine has been in operation for a period of time, it is necessary to restock the vending machine with products to be sold. When this is to be done, a supply of each of the products for a vending machine is transported to the vending machine. The dispensing devices are then stocked with new products or with products which correspond to products which were previously sold. In restocking the vending machine, products which sell for the same price and which are identical to other products in a dispensing device are positioned in the dispensing device.
SUMMARY OF THE INVENTION
The present invention provides a vending machine having a plurality of product dispensing devices. Each of the product dispensing devices holds a next product to be dispensed from the dispensing device and a plurality of products which are located at product storage locations in the product dispensing device. The products at the storage locations are sequentially moved to the product dispensing location.
When a customer selects a product, the product is moved from one of the product dispensing locations to a product retrieval location where the customer has access to the selected product. The selected product moves from one of the product dispensing devices along a path which extends to the product retrieval location. In accordance with one of the features of the present invention, an image of the selected product is obtained as the selected product moves along the path toward the product retrieval location.
As the selected product moves along the path toward the product retrieval location, a plurality of images of a selected portion of the path are sequentially obtained and transmitted to a data base. Each of the images is compared to an image in a data base to determine when a product has moved into the image. In response to movement of the product into the image, controls in the vending machine determine that a product has moved to the product retrieval location.
The present invention has a number of different features. These features may be utilized together as disclosed herein. These features may be utilized separately and/or in various combinations with each other or the prior art.



BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other features of the present invention will become more apparent upon a consideration of the following description taken in connection with the accompanying drawings wherein:
FIG. 1 is a schematic illustration of a vending machine which is constructed and operated in accordance with the present invention;
FIG. 2 is an enlarged fragmentary schematic illustration depicting the manner in which products are held by dispensing devices in the vending machine of FIG. 1;
FIG. 3 is an enlarged fragmentary schematic illustration depicting the manner in which imaging devices are mounted in the vending machine of FIG. 1;
FIG. 4 is a schematic illustration of controls for the vending machine of FIG. 1;
FIG. 5 is a fragmentary schematic illustration depicting the manner in which an imaging device may be mounted on a movable carriage in the vending machine of FIG. 1;
FIG. 6 is a fragmentary schematic illustration, generally similar to FIG. 4, of a second embodiment of controls for the vending machine of FIG. 1;
FIG. 7 is an enlarged schematic illustration, generally similar to FIG. 2, depicting the relationship between product dispensing devices and a shelf at a product retrieval location; and
FIG. 8 is a pictorial illustration obtained with an imaging device as a product selected by a customer moves toward the product retrieval location.



DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION
General Description
A vending machine 10 (FIG. 1) is constructed and operated in accordance with the present invention. The vending machine 10 includes a rectangular housing 12 having side walls 14 and a door 16. The door 16 has a transparent window or panel 20. The door 16 is pivotally mounted on hinges (not shown) connected to the side walls 14 in a known manner.
Disposed within the housing 12 are a plurality of product dispensing devices 24. The product dispensing devices 24 are visible through the glass window 20 in the door 16. In FIG. 1, the product dispensing devices 24 are all shown as being empty, that is, before the product dispensing devices are stocked with products 28 (FIG. 2). It should be understood that the product dispensing devices may have any desired construction and be used to dispense any desired product. It should also be understood that the door 16 may not have a transparent window through which the product dispensing devices 24 are visible.
The location of the product dispensing devices 24 in the vending machine 10 is indicated by indicia 32 (FIGS. 1 and 2). The indicia 32 is associated with each of the dispensing devices 24. The indicia 32 indicates the location of the dispensing devices 24 in the machine 10.
In the illustrated embodiment of the invention, the indicia 32 is of the alpha numeric type. The indicia 32 includes a letter which designates the row in which a dispensing device is found in the vending machine 10. Thus, the rows are designated A, B, C, D, E, and F. The numerals in the indicia 32 indicate the position of the dispensing devices 24 in the particular row. Thus, A1 indicates the first product dispensing device 24 in the upper row of product dispensing devices. The indicia 32 may include two numbers instead of a letter and a number. Alternatively, the indicia 32 may include two letters instead of a letter and a number.
In addition to the indicia 32, an electronically changeable price display 36 (FIG. 2) is provided in association with each of the dispensing devices 24. The price display 36 indicates the price of the next product 28 to be dispensed by the dispensing device. The indicia 32 and the price display 36 are clearly visible to a potential customer through the transparent window 20 in the door 16.
If desired, the vending machine 10 may have a door which blocks a potential customer's view of the dispensing devices 24. If this is done, the price display 36 would be visible on the front of the vending machine along with indicia indentifying the products with which the prices are associated.
Each of the dispensing devices 24 includes a conveyor assembly 40 (FIG. 2) which engages the products 28. Each of the conveyor assemblies 40 has a known construction. Each of the illustrated conveyor assemblies 40 includes a pair of helical conveyor elements 42 and 44 which engage the products 28. The helical conveyor elements 42 and 44 are rotatable about their parallel longitudinal central axes relative to a tray 48 on which the products 28 are disposed. The helical conveyor elements 42 and 44 may be referred to as “spirals”. If desired, a conveyor assembly 40 may include only single conveyor element 42 or 44.
When a product 28 is to be dispensed from a product dispensing location 54 and a next succeeding product is to be advanced from a storage location 52 (FIG. 2) to the product dispensing location, the helical conveyor elements 42 and 44 are rotated in opposite directions about their longitudinal central axes. Thus, the conveyor element 42 is rotated in a counterclockwise direction (as viewed in FIG. 2) about its longitudinal central axis while the conveyor element 44 is rotated in a clockwise direction about its longitudinal axis.
This rotation of the two conveyor elements 42 and 44 is effective to move the product 28 at the dispensing location 54 off of the tray 48 so that the product drops downward between the trays 48 and the window 20 in the door 16 (FIG. 1). The dispensed product 28 drops onto a shelf (not shown in FIGS. 1-4) at a product retrieval location 60 (FIG. 1) in the vending machine 10. The customer then manually pivots a delivery door 62 to gain access to the product on the shelf. At the same time, the conveyor elements 42 and 44 move a next succeeding product 28 from a product storage location 52 to the product dispensing location 54 (FIG. 2). If desired, a product retrieval location 60 having a different construction may be utilized.
Although the illustrated conveyor assemblies 40 utilize helical conveyor elements 42 and 44 to sequentially move products 28 forward from storage locations 52 toward the product dispensing location 54, one or more of the conveyor assemblies 40 may include only a single helix. A different type of conveyor assembly may be utilized if desired. For example, indexing or pusher elements may be connected with a continuous belt or chain conveyor and utilized to push the products 28 to the dispensing location 54 and then to push each product in turn from the dispensing location. Alternatively, a circular disc may be intermittently rotated to move products 28 to a dispensing location. The disc may be rotated to dispense a product from the dispensing location. As another example, a gravity feed conveyor may be utilized.
The products 28 have been illustrated in FIG. 2 as being bags which hold the product being dispensed, for example, potato chips or popcorn. However, the product 28 may be different from the illustrated product. For example, the product may be containers (bottles and/or cans) of liquid, candy bars, video tapes, or compact discs. It should be understood that any one of many different types of known conveyor assemblies may be utilized in place of the conveyor assembly 40 to dispense many different known products in place of the illustrated products 28.
A control panel 70 (FIG. 1) is mounted on the door 16 of the vending machine 10. The control panel 70 includes various items with which a customer interacts to purchase one or more products being sold by the vending machine 10. The control panel 70 includes a bill validator insert 74 where paper money may be inserted into the vending machine 10. In addition, the control panel 70 includes a coin insert 76 where coins may be inserted into the vending machine 10. If used, a coin scavenger button 78 is manually actuatable to have coins returned at a coin return 80. Rather than depositing money, a credit/debit card may be used to pay for a purchase. A credit display window 82 indicates the amount of money which has been deposited or charged.
A selector switch keyboard 84 is manually actuatable to enable a product letter and number, corresponding to the indicia 32 associated with the products, to be entered. When the indicia corresponding with a desired product is entered at the keyboard 84, a product dispensing device 24 for the selected product is activated to move the selected product 28 from the dispensing location 54. Operation of the selected product dispensing device is also effective to move a next succeeding product 28 to the product dispensing location 54.
As the selected product moves from the product dispensing location, it falls downward to the product retrieval location 60. If the customer is entitled to change from the money which was inserted into the machine, the change is returned at the coin return 80. It should be understood that the selected product 28 may reach the product retrieval location 60 in ways other than falling. For example, the product could be scooped up or set on a shelf. If desired various elevators or X/Y delivery systems may be used.
In addition, the control panel 70 includes a display 88 where indicia relative to a selected product 28 may be displayed. This indicia may indicate the characteristics of the selected product, such as the number of calories, ingredients and/or food value. If desired the display 88 may be omitted.
The illustrated vending machine 10 has the same general construction and mode of operation as a Model 148 which is commercially available from Crane-National Vendors having a place of business at 12955 Enterprise Way, Bridgeton, Mo. 63044. However, it should be understood that the vending machine 10 may have a different construction. The features of the invention are not to be considered as being limited to vending machines made by Crane-National Vendors or to any specific type of vending machine.
Product Imaging
A plurality of imaging devices 100 are provided to obtain visual images of the next products 28 to be dispensed. The next products 28 to be dispensed are the products at the dispensing locations 54 (FIG. 2) in each of the dispensing devices 24.
In the illustrated embodiment of the invention, the imaging devices 100 are disposed on an inner side surface 106 of the window 20 (FIGS. 1 and 3). The window mounted imaging devices 100 face inward toward the product dispensing devices 24. It should be understood that the imaging devices 100 may be positioned at locations other than on the transparent panel of the window 20. For example, the imaging devices 100 may be mounted on the housing 12 and/or frame of the door 16.
In the illustrated embodiment of the vending machine 10, the door 16 has a transparent window 20 on which the imaging devices are mounted. However, the door 16 may be opaque. If this is the case, the imaging devices 100 may be mounted on an opaque panel on the inside of the door 16.
In the illustrated embodiment of the invention, the imaging devices 100 are color digital camera modules. The imaging devices 100 convert a visual image, which may be referred to as an optical image, to an electrical signal. The specific imaging devices 100 illustrated in FIG. 3 are color digital cameras which are commercially available from STMicroelectronics having places of business at 1000 E. Bell Road, Phoenix, Ariz. 85022, USA and at 39, Chemin du Champ des Filles, C.P. 21, CH 1228 Plan-Les-Ouates, Geneva, SWITZERLAND and is commercially available under the designation of ST VL6624/VS6624. It should be understood that imaging devices other than this specific imaging device may be utilized if desired. Thus, any imaging device which converts a visual (optical) signal to an electrical signal may be utilized.
Controls 106 (FIG. 4) are connected with the product dispensing devices 24, imaging devices 100, and control panel 70. The controls 106 effect operation of each of the imaging devices 100 to obtain initial images of all the products 28 (FIG. 2) disposed at the dispensing locations 54 each time the vending machine 10 is stocked with products 28. Thus, a visual image of each of the products at the dispensing locations 54 in all of the product dispensing devices 24 in the vending machine 10 is obtained by activating each of the imaging devices 100 upon completion of stocking of the vending machine 10. The controls 106 are disposed in the housing 12.
Thereafter, only an imaging device 100 associated with a product location indicated by the indicia 32 (FIG. 2) of a product dispensed from the vending machine 10 is activated. Thus, after a product 28 has been dispensed from a product dispensing device 24 and a next succeeding product has been moved to the product dispensing location 54, only one imaging device 100 (FIGS. 1, 3 and 4) is activated to obtain a visual image of the product 28 which was just moved from a storage location 52 to a product dispensing location 54 (FIG. 2). If desired, more than one imaging device 100 may be activated to obtain more than one image of the product 28 which was just moved to a product dispensing location.
After the vending machine 10 has been stocked, all of the imaging devices 100 are activated to obtain images of all of the products 28 at all of the product dispensing locations 54. Thereafter, each time a product 28 is dispensed from a product dispensing location 54 and a next succeeding product has been moved from a storage location 52 to a dispensing location, only one of the imaging devices 100 is activated to obtain an image of the next succeeding product 28 which was moved to a product dispensing location 54. As was previously mentioned, more than one imaging device 100 may be activated to obtain images of the next succeeding product 28 which is moved to a product dispensing location 54.
When a product 28 (FIG. 2) is dispensed from the product dispensing location 54, the product drops downward (as viewed in FIG. 1) between the window 20 and the trays 48 (FIG. 2) of product dispensing devices 24. As the product 28 moves downward to the product retrieval location 60, an imaging device 110 (FIG. 4) is activated to obtain an image of the product while it is dropping and/or while it is at the retrieval location 60. The imaging device 110 is a color digital camera and has the same construction as the imaging devices 100. As was previously mentioned, the product 28 may be moved to the retrieval location in a manner other than by falling downward.
Rather than using an imaging device 110 to detect dispensing of a product 28, a different product detection system may be utilized to detect dispensing of a product. For example, a product drop detection system similar to the system disclosed in U.S. Pat. No. 6,920,372 may be utilized. Of course other known product drop detection systems may be utilized if desired, such as Is VendWizardTM available from Vendor Exchange International, Inc. in Cleveland, Ohio.
Although only a single imaging device 110 for obtaining an image of a product 28 at the product retrieval location 60 is illustrated in FIG. 4, it should be understood that a plurality of imaging devices 110 may be provided in the vending machine 10. For example, an imaging device 110 may be mounted on the right side of the housing 12 (FIG. 1) and a second imaging device 110 may be mounted on the left side of the housing to obtain views of the product retrieval location 60 and a dispensed product from different locations. If desired, the imaging devices 110 for imaging the product as it drops and/or is at the retrieval location 60 may be mounted on the window 20 of the door 16 rather than the housing 12.
The imaging devices 100 and 110 convert an optical image of a product 28 to an electrical signal which is representative of the image. The electrical signals corresponding to images of product 28 are transmitted from the imaging devices 100 and 110 to a computer 114 (FIG. 4) in the controls 106. A comparator 116 compares features of the images represented by the electrical signals transmitted from the imaging devices 100 and 110 to a data base 120 of features. By comparing the electrical signals representative of the visual (optical) images obtained with the imaging devices 100 and 110 to the data base 120, the identity of a product 28 corresponding to a visual image obtained by an imaging device can be determined.
The data base 120 includes a product price data base 122. Once the identity of a product 28 has been determined, the price of the product can be determined from the product price data base 122. The computer 114 compares the price of a product 28, as determined by the data base 120, with the price set forth at the display 36 associated with the product. If the price set forth at the display 36 is different than the product price, as determined by the data base 120, the computer 114 changes the display to agree with the price determined by the data base.
If desired, once the identity of a product has been determined, the computer can reset the price at the display 36 without comparing the price of the product to the displayed price. This would result in the display 36 being reset automatically each time the identity of a product is determined. When the display is reset, the displayed price may or may not change.
The display 36 may include liquid crystal display components or light emitting diode components. The display is electrically energized to set forth the correct price of the product at the dispensing location 54 associated with the display. The display 36 may be energized by the computer 114 to set forth the price of a product, in a known manner, with seven segment numerals. It should be understood that the display 36 may have any desired construction so long as the computer 114 can effect a change in the price set forth at the display.
As was previously mentioned, the display 36 may be disposed on the outside of the vending machine 10. If this is done the door 16 may be constructed so as to block a customer's view of the dispensing devices 24. The imaging devices 100 would be disposed inside the vending machine 10 and would not be visible to a customer.
When a product 28 is dispensed from the dispensing location 54 (FIG. 2), a next succeeding product is moved from a storage location 52 to the dispensing location. Thereafter, at least one of the imaging devices 100 (FIGS. 1 and 4) is activated to obtain a visual image of the next succeeding product 28 which is moved to the product dispensing location 54. If desired, a plurality of imaging devices 100 may be activated to obtain a plurality of images of the next succeeding product 28. The computer 114 (FIG. 4) effects operation of the comparator 116 to compare the image or images of the next succeeding product to the data base 120. This enables the identity of the next succeeding product to be determined.
Once the identity of the next succeeding product moved to a dispensing location 54 has been determined, the price of the product can also be determined from the product price data base 122. The computer 114 compares the price indicated by the price display 36 with the price of the next succeeding product as determined by the data base 120 and visual image of the product. If the price indicated by the price display 36 is different than the price determined from the product price data base 122, the price indicated by the price display 36 is changed to indicate the correct price for the product which is moved from the storage location to the dispensing location 54. This enables products having different prices to be sequentially dispensed from the same dispensing location 54 while indicating the correct price for the particular product which is at the dispensing location and obtaining the correct amount of money from a customer who selects that product.
When the price at a display 36 is changed, the amount of money which a customer must pay for the associated product changes. When a customer selects the product, the computer 114 causes the control panel 70 to require the correct amount of money for the product. Thus, when the price display 36 is changed, corresponding changes are made in the amount required at the control panel 70.
Images obtained by activating the imaging devices 100 and 110 (FIG. 4) are identified by comparing the images obtained from the imaging devices with the data base 120. The data base 120 includes an aspect ratio data base 126 which contains data corresponding to the aspect ratio of each of the products 28 (FIG. 2) to be dispensed from the vending machine 10. The aspect ratio of a product is the ratio of the product image height divided by the product image width for a particular product. If desired, the imaging devices 110 may be eliminated. If this is done, other product detection devices may be substituted for the imaging devices 110.
It is contemplated that many different products 28 will be dispensed from the vending machine 10. These products may have different aspect ratios. For example, the aspect ratio of a candy bar will be substantially different than the aspect ratio of a bag containing chips or other articles. Similarly, the aspect ratio of beverage containers will be substantially different than the aspect ration of a bag containing a solid food product. The aspect ratio of an image obtained with an imaging device 100 or 110 is compared to the aspect ratios in the aspect ratio data base 126 (FIG. 4) to assist in identifying the product in the visual image obtained by an imaging device 100 or 110.
A color histogram data base 130 (FIG. 4) contains representations of frequency distributions of colors corresponding to the colors of all the products 28 sold in the vending machine 10. The color histogram for a particular product 28 is obtained by counting the number of pixels of each of a given set of color ranges in two dimensional color space. The color space of the image is partitioned into a number of spaces, for example eight spaces. For each partition, the pixels with a color within the range of the partition are counted. This results in a representation of the relative frequency of the colors of the visual image of a product obtained with an imaging device 100 or 110.
The color histogram for a particular product 28 is a representation of the distribution of colors in an image of the product. The color histogram is derived by counting the number of pixels of each of a given set of color ranges in a color space. The histogram provides a compact summarization of the distribution of data relating to color in an image. The color histogram of an image is relatively invariant with translation and rotation about a viewing axis. By comparing histograms of two images and matching the color content of one image with the other, the color histogram is particularly well suited to the problem of recognizing an object of unknown position and rotation.
In addition to the aspect ratio data base 126 and color histogram data base 130, the data base 120 includes a scale invariant feature data base 132 (FIG. 4). The scale invariant feature data base 132 is a data base of product features which are invariant to image scaling and rotation. In addition, these features are at least partially invariant to changes in illumination and view point of the imaging devices 100 and 110.
In comparing features of an image of a product 28 to the data base 132, the image is matched by comparing each feature from the image to the data base and finding matching features based on Euclidian distance of the feature vectors. The manner in which scale invariant features are utilized in the data base 132 is similar to the description in U.S. Pat. No. 6,711,293 to David G. Lowe and entitled Method and Apparatus for Identifying Scale Invariant Features in an Image and Use of Same for Locating an Object in an Image. The disclosure in the aforementioned U.S. Pat. No. 6,711,293 is hereby incorporated herein in its entirety by this reference thereto.
It should be understood that the data base 120 may identify products by comparing features other than aspect ratio, color and scale invariant features. For example, a bar code or other encoded data on a product 28 may be used alone or in combination with various features of a product to identify the product. It is contemplated that various combinations of encoded data, pixel data, metadata and other data may be utilized to identify the products.
In addition to the data base 120, the controls 106 include a transmitter 136 which is operable to transmit a signal, indicated schematically at 138 in FIG. 4, to a base station which is remote from the vending machine 10. The signal 138 transmits to the base station the identity and number of products sold. In addition, the signal 138 may indicate the total amount of money which was collected from customers making the sales. Alternatively, the signal 38 may transmit the identity and number products sold.
The base station would be able to determine the amount of money collected from customers as a function of the known price of the various products. Thus, the signal 138 may indicate the number of each of the products sold and the cost of each of those products. The base station may be in a building and/or vehicle.
Based on the information which is transmitted from the vending machine 10 by the transmitter 136, the number of each product sold can be determined. To facilitate restocking, this information is utilized to prepare a kit or group of products containing numbers of each product corresponding to the number of each product which were sold from the vending machine 10. When the vending machine 10 is to be restocked, this kit or group of products is taken to the vending machine and is utilized to replace the products that were previously sold from the vending machine. In addition, the amount of money to be collected from the vending machine 10 during restocking can be determined from the information provided by the signal 138.
If desired, DEX (Data Exchange Uniform Code Standard) may be utilized with the controls 106. The transmitter 136 would transmit data in regard to the identity and number of each product 28 sold, the amount of money collected, the service history of the vending machine 10, and other information. In addition, the data transmitted by the transmitter 136 would indicate products 28 which are not selling well. Associated software may suggest that if one particular product 28 is selling well that another product, if stocked in the vending machine 10, will sell well.
Operation
When the vending machine 10 (FIG. 1) has been in use for a period of time, it is contemplated that the vending machine will have to be restocked with products 28 (FIG. 2) to be sold from the vending machine. When this is to be done, data transmitted from the vending machine 10 by the transmitter 136 (FIG. 4) to a base location will be reviewed. When this is done, the identity and number of each of the products which have been sold from the vending machine are determined. The data transmitted from the vending machine 10 eliminates the need to rely upon restocking data which is of questionable validity. The base location may be a warehouse and/or vehicle (truck).
A kit or box of products corresponding to the identity and number of products which have been sold from the vending machine 10 will then be prepared. The number of each of the various products 28 sold from the vending machine 10 is determined and a similar number of each of the various products is placed in the box or kit. This will enable a person who is restocking the vending machine 10 to replace each product which has been sold from the vending machine without transporting excess products.
When the vending machine 10 is to be restocked, a combination door handle and lock 144 (FIG. 1) is actuated and the door 16 is pivoted to an open condition. When the door 16 has been opened, access is provided to the product dispensing devices 24. The person restocking the product dispensing devices 24 can readily position products 28 from the kit or box of products in empty storage locations 52 in the product dispensing devices.
It is contemplated that most of the product dispensing devices 24 will contain only one specific product 28. However, if desired, a variety of products may be provided in one of the product dispensing devices 24. These variety of products may have a variety of different prices.
Thus, bags of chips selling for seventy-five cents, bags of candy selling for eighty-five cents, and bags of other articles selling for one dollar may all be positioned in storage locations 52 in a single product dispensing device 24. During restocking of the vending machine 10, a product may inadvertently be placed in one product dispensing device 24 when it should have been positioned in a different product dispensing device. The controls 106 (FIG. 4) will identify each of the products 28 to be dispensed. The controls 106 will effect any necessary changes in the price display 36 (FIG. 2) associated with a product 28 at a dispensing location 54 to indicate the correct price for the product.
Once the product dispensing devices 24 have been restocked, that is, have been filled with products to be sold, the door 16 is moved from the open position to a closed position. As the door 16 is closed, a switch 148 (FIG. 3) is actuated. Actuation of the switch 148 indicates to the computer 114 (FIG. 4) that the door has been closed and restocking of the vending machine completed.
The switch 148 (FIG. 3) may be connected to the main power supply for the vending machine. When the door 16 is opened, the switch 148 opens and interrupts the power supply. When the door 16 is closed, the switch 148 closes and reconnects the power supply. Alternatively, the switch 148 may be connected with just the computer 114 and not the main power supply. A suitable sensor, to detect opening and closing of the door 16 may be utilized in place of the switch 148. Alternatively, a button or switch may be manually actuated after the door 16 is closed.
When the door closes, the computer 114 (FIG. 4), initiates operation of the imaging devices 100 to obtain images of the products at the dispensing locations 54 in all of the product dispensing devices 24. The imaging devices 100 convert the visual (optical) images of the products 28 at the product dispensing locations 54 in the product dispensing devices 24 to electrical signals. These electrical signals are representative of the images of the products 28.
The electrical signals are transmitted from all of the imaging devices 100 to the computer 114 (FIG. 4). The computer 114 initiates comparison of features of the images represented by the electrical signals with data in the data base 120. This comparison enables the computer 114 to determine the identity of each of the products 28 at each of the product dispensing locations 54 in the product dispensing devices 24.
To identify a product 28 at a dispensing location 54, the aspect ratio of the image of the product to be identified is compared to aspect ratios in the aspect ratio data base 126. The image of the product 28 to be identified is compared to the color histograms in the color histogram data base 130 for images having aspect ratios corresponding to the aspect ratios associated with the images of the product 28 to be identified. The scale invariant features of the image are compared to the scale invariant feature data base 132 for images having aspect ratios and color histograms corresponding to scale invariant feature data in the data base 132. It should be understood that the image of a product may be compared to the data bases 126, 130 and 132 in any desired order.
The identity of each of the products 28 at each of the product dispensing locations 54 is determined in this manner. Once the identity of each of the products at each of the product dispensing locations 54 has been determined, the price of each product is determined from the product price data base 122. If the display 36 for a particular product is not in agreement with the product price for the product which was identified as being present at the product dispensing location 54, the price display 36 is changed to indicate the correct product price.
Once the foregoing initialization of the vending machine 10 has been accomplished by identifying the next product 28 to be dispensed from each of the product dispensing locations 54 in each of the product dispensing devices 24 and after the price displays 36 have been set to the correct amounts, the vending machine 10 is ready to serve customers. When a customer approaches the vending machine 10, the products 28 at the product dispensing locations 54 (FIG. 2) in the product dispensing devices 24 are illuminated by a cabinet light assembly 152 (FIG. 3). The customer views the products 28 and the price displays 36 through the transparent window 20 in the door 16 of the vending machine 10.
The cabinet light assembly 152 may have any desired construction. The cabinet light assembly 132 may have a vertical axis. The cabinet light assembly 132 may be mounted on the side walls 14 of the housing 12.
After a customer has selected a particular product, he inserts money to pay for the product into the control panel 70 (FIGS. 1 and 4). Paper money is inserted at the bill validation insert 74. Coins are inserted at the coin insert 76. A location maybe provided for insertion of a credit/debit card. The customer is informed as to the amount of money which he has deposited into the vending machine by indicia at the credit display window 82 on the control panel 70.
Once the customer has deposited the requisite amount of money into the vending machine 10, the customer manually actuates the selector switch keyboard 84 on the control panel 70. The customer actuates keys on the selector switch keyboard 84 to enter indicia indicative of the indicia 32 indicating the location of the selected product dispensing device 24. The location of the product dispensing device 24 selected by a customer is transmitted from the selector switch keyboard 84 to the computer 114.
At this time, the display 88 may set forth indicia indicative of characteristics of the selected product. For example, the display 88 may indicate the number of calories, other food value information, and/or ingredients of the selected product. In addition, the display 88 may indicate the brand name of the product and/or special offers or promotions. Of course, if the selected product 28 is not food, the indicia at the display would indicate the identity of the selected product and features of the product, such as for a booklet, the title and number of pages.
Once the keyboard 84 has been actuated to enter indicia corresponding to the indicia 32 indicating the location of the selected product 28, the computer 114 (FIG. 4) effects operation of one or more motors 156 in the product dispensing device 24 at the selected product location indicated by the indicia 32 entered into the keyboard 84 of the control panel 70. The motor 156 effects rotation of the helical conveyor elements 42 and 44 in the selected product dispensing device 24. As was previously mentioned, the dispensing devices 24 may have a different construction if desired. It is contemplated that the dispensing devices 24 may have any one of many known constructions.
The helical conveyor elements 42 and 44 are rotated in opposite directions about their longitudinal central axes. Thus, the helical conveyor element 42 is rotated in a counterclockwise direction (as viewed in FIG. 2) about its longitudinal central axis while the helical conveyor element 44 is rotated in a clockwise direction about its longitudinal central axis. Although a single motor 156 has been shown in FIG. 4 as being connected with two helical conveyor elements 42 and 44, a separate motor may be provided for each of the conveyor elements. Of course, one or more of the dispensing devices 24 may have only a single helical conveyor element.
Rotation of the helical conveyor elements 42 and 44 by a motor 156 (FIG. 4) moves the product 28 at the selected product dispensing location 54 off of the tray 48 (FIG. 2). The selected product 28 then drops downward from the product dispensing device 24 to the product retrieval location 60 (FIG. 1). At the same time, rotation of the helical conveyor elements 42 and 44 (FIG. 2) advance the next succeeding product 28 from a storage location to the product dispensing location 54. Similarly, the other products 28 disposed in storage locations 52 in the selected product dispensing device 24 are advanced toward the product dispensing location 54 by the rotation of the helical conveyor elements 42 and 44.
As the selected product 28 falls downward to the product retrieval location 60, the imaging device 110 (FIG. 4) is activated to obtain a visual image of the dispensed product. The imaging device 110 converts the optical image of the dispensed product to an electrical signal which is transmitted to the computer 114. The electrical signal transmitted from the imaging device 110 to the computer 114 confirms dispensing of a product.
The foregoing description has been in association with dispensing devices 24 having helical conveyor elements 42 and 44. It is contemplated that the dispensing devices 24 will have a construction which is adapted to handling of the particular product 28 to be dispensed. For example, a dispensing device 24 to be used in association with containers of liquid would have a construction which is different than a dispensing device to be used in association with bags of chips or candy.
The comparator 116 compares features of the image of the dispensed product to the data base 120 to determine the identity of the dispensed product. This enables the computer 114 to confirm that the selected product was indeed dispensed from a product dispensing device 24 to the product retrieval location 60. However, if the image of the dispensed product obtained by operation of the imaging device 110 is inadequate to enable the comparator 116 and computer 114 to determine the identity of the dispensed product, the image will at least confirm that a product was dispensed.
In the unlikely event that the imaging device 110 does not obtain an image of a dispensed product 28, the computer 114 (FIG. 4) receives an indication of malfunctioning of the selected product dispensing device 24. The computer 114 then effects operation of the selected motor 156 with a jogging or intermittent operation in a further effort to dispense the selected product 28. If this intermittent operation of the motor 156 is successful, the intermittent or jogging operation of the motor 156 is interrupted when the imaging device 110 successfully obtains a visual image of the selected product 28 at or moving toward the product retrieval location 60.
If the intermittent or jogging operation of the motor 156 is ineffective to cause the product dispensing device 24 to dispense the selected product 28, the computer 114 changes the display window 88 to indicate to the customer that another selection is to be made. The computer 114 gives the customer credit for the money that has already deposited in the vending machine 10 and allows the customer to make a selection of a product 28 of equal or lesser cost. Of course, if the product of lesser cost is selected, the computer 114 effects operation of the vending machine 10 to refund the excess amount of money which the customer deposited. Alternatively, the computer 114 could immediately give the customer a refund if a product is not dispensed.
The computer 114 periodically activates the transmitter 136 to transmit a signal 138 (FIG. 4) to a base or remote location. The signal 138 indicates the identity of the products which have dispensed and indicates the prices of the products. This enables personnel at the base or remote location to determine how much money has been deposited in the vending machine and to determine what products need to be brought to the vending machine in order to restock the vending machine. The transmitter 136 may be of either the radio or telephone type. Of course, other types of transmitters may be utilized if desired. If desired, the computer 114 could activate the transmitter 136 to transmit data in response to a signal from a base station.
During operation of the motor 156 to rotate the helical conveyor elements 42 and 44 in the selected product dispensing device 24, the first product 28 (FIG. 2) is dispensed from the product dispensing location 54 and a second product moves from a storage location 52 to the dispensing location (FIG. 2). The second product 28 which is moved from a storage location 52 to the dispensing location 54 may or may not be the same as the product 28 which was previously at the dispensing location and was selected by a customer.
After a second product has been moved from a storage location 52 to a product dispensing location 54, one of the imaging devices 100 is activated by the computer 114 to obtain a visual image of the second product 28 at the dispensing location 54. The computer 114 activates only the imaging device 100 which is positioned to obtain a visual (optical) image of the product 28 at the dispensing location 54 from which a selected product was previously dispensed. Since a product 28 was dispensed from only one of the product dispensing locations 54, the computer 114 maintains the imaging devices 100 associated with other product dispensing locations inactive.
The imaging device 100 which is activated to obtain a visual image of the second product 28 at the product dispensing location 54 converts the optical image to an electrical signal. This electrical signal is transmitted to the computer 114. The computer 114 effects operation of the comparator 116 to compare features of the visual image of the second product to features in the data base 120 to determine the identity of the second product.
The identity of the second product 28 at the product dispensing location 54 may be the same as the identity of the product which was previously dispensed from the product dispensing location 54. However, it is contemplated that the identity of the second product 28 which replaces the previously dispensed product may be different than the identity of the previously dispensed product. If this is the case, the computer may effect an increase or decrease in the price display 36 associated with the product dispensing device 24 in which the second product was moved to the product dispensing location 54 to replace a previously dispensed product. The price display 36 associated with this product dispensing device 24 is changed to indicate the price of the product which is presently at the product dispensing location 54, that is, the price of the second product.
It is possible that a dispensing device 24 may fail to move a product 28 from a storage location 52 to a product dispensing location 54 after a product is dispensed. In the unlikely went that this occurs, activation of an imaging device 100 to obtain a visual image of the product dispensing location 54 from which a product was dispensed will result in an image of an empty dispensing location. When the image of an empty product dispensing location 54 is compared to the data base 120 by the comparator 116, the result is a signal to the computer 114 indicating the empty dispensing location. In response to this signal, the computer 114 will effect operation the one dispensing device 24 having an empty product dispensing location 54. This operation of the dispensing device will move a product 28 from a storage location 52 to the empty product dispensing location 54.
Since the product which is moved from a storage location 52 to a product dispensing location 54 in a product dispensing device 24 is identified each time a product is dispensed from the product dispensing device, different products can be sequentially dispensed from a single product dispensing device 24. The price display 36 is adjusted to accommodate the different prices of different products. This enables different products to either be intentionally or inadvertently positioned in a single product dispensing device 24 during restocking of the vending machine 10.
Images
It is contemplated that an imaging device 100 may be provided for each of the product dispensing devices 24 in the vending machine 10. The specific vending machine 10 illustrated in FIG. 1 has twenty-four dispensing devices 24. Thus, twenty-four imaging devices 100 may be provided for the vending machine 10. Of course, the vending machine 10 may be provided with either a greater or lesser number of product dispensing devices 24 and either a greater or lesser number of imaging devices 100.
Rather than providing one imaging device 100 for each product dispensing device 24, it is contemplated that it may be desirable to have each imaging device associated with a plurality of product dispensing devices. If each imaging device 100 is associated with a plurality of product dispensing devices 24, the number of imaging devices required for a particular vending machine 10 is reduced. Of course, this simplifies construction or retrofitting of the vending machine 10.
In the vending machine 10 illustrated schematically in FIG. 1, two product dispensing devices 24 are associated with each imaging device 100. When one of the imaging devices 100 is activated to obtain a visual (optical) image, the image will be of two product dispensing devices 24. These two product dispensing devices 24 will have two product dispensing locations 54 in which products 28 are disposed. This results in the image obtained from one of the imaging devices 100 being similar to the illustration depicted in FIG. 2.
The half of the image corresponding to the product dispensing device 24 from which a product was just dispensed is designated by the computer 114 as being an area of interest. Thus, if a product was dispensed from location A1 of FIG. 2, the left (as viewed in FIG. 2) half of the image obtained by activation of the imaging device 100 associated with the two product dispensing devices 24 illustrated in FIG. 2 would be of interest. Similarly, if the product had been dispensed from the location designated A2 by the indicia 32 in FIG. 2, the right (as viewed in FIG. 2) half of the image would be designated by the computer 114 as being the area of interest.
Rather than comparing the images of both the location indicated by the indicia A1 and the location indicated by A2 with the data base 120, only the image in the area of interest is compared with the data base 120. Thus, if the product which was dispensed came from the product dispensing location designated A1 by the indicia 32, only the left (as viewed in FIG. 2) half of the image would be designated as being of interest and would be compared to the data base 120. Similarly, if the product which was dispensed came from the product dispensing location designated A2 by the indicia 32, only the right half of the image would be designated as being of interest and would be compared to the data base 120.
Since two product dispensing devices 24 are viewed by each imaging device 100, there are half as many imaging devices 100 as there are product dispensing devices 24. In the specific vending machine 10 illustrated in FIG. 1, there are twenty-four product dispensing devices 24 and twelve imaging devices 100. Of course, a greater or lesser number of product dispensing devices 24 may be provided in association with a particular vending machine 10. In addition, a greater or lesser number of imaging devices 100 may be associated with a particular vending machine 10.
If desired, the imaging devices 100 may be constructed and positioned so as to view more than two product dispensing devices 24. Thus, a single imaging device 100 may be constructed and positioned so as to view three or more product dispensing devices 24. It is contemplated that an imaging device 100 may be constructed so as to view ten dispensing devices 24. This would enable a vending machine 10 having forty dispensing devices 24 to use only four imaging devices 100.
In the embodiment of the invention illustrated in FIGS. 1-4, the imaging devices 100 are positioned so that they view product dispensing devices 24 disposed on a single tray 48, that is, product dispensing devices 24 at the same vertical level. However, it is contemplated that the imaging devices 100 may be constructed and positioned so as to view product dispensing devices 24 on more than one tray 48. Thus, the product imaging devices 100 may be constructed and positioned so as to view two dispensing devices 24 on each of two trays. In this specific example, the imaging devices may be positioned so as to view product dispensing devices designated A1 and A2 (FIG. 2) and B1 and B2 (FIG. 1) disposed immediately beneath the product dispensing devices designated A1 and A2.
It is contemplated that each dispensing device 24 may be viewed by more than one imaging device. For example, each dispensing device 24 may be viewed by two imaging devices mounted at spaced apart locations in the vending machine 10. This would enable the comparator 116 to compare two different images of a product 28 at one dispensing location 54 to the data base 120 to identify the product at the dispensing location.
Mounting an Imaging Device
In the specific embodiment of the invention illustrated in FIGS. 1-4, the imaging devices 100 are mounted in a stationary relationship with the product dispensing devices, as long as the door 16 is closed. Thus, the imaging devices 100 are mounted on the inner side surface 106 (FIG. 3) of the transparent window 20 in the door 16. In this embodiment of the invention, the imaging devices 100 are fixedly secured to the inner side surface 106 of the window 20. This may be done with a suitable adhesive or other fastener.
It should be understood that the imaging devices 100 may be mounted in a different manner if desired. For example, the window 20 may be provided with mullions and/or muntins on which the imaging devices 100 are mounted. Alternatively, some or all of the imaging devices 100 may be mounted on the frame of the door 16 or on side walls of the housing 12.
In the embodiment of the invention illustrated in FIG. 5, an imaging device 100 is mounted on a carriage 162 which is movable along a track 164. A drive mechanism, such as a screw or gear drive, may be associated with the carriage 162 to move it along the track 164. It is contemplated that the track 164 may be mounted on the window 20. Alternatively, the track 164 may be offset to one side of the window 20 on the door 16. If desired, the track 164 may be mounted on the side walls 14 of the housing 12.
In the embodiment of the invention illustrated in FIG. 5, the track 164 is stationary relative to the housing 12. However, it is contemplated that the track may be movable relative to the housing. For example, one end of the track 164 may be mounted for pivotal movement relative to the housing 12. Alternatively, the track 164 may be mounted for linear movement relative to the housing 12.
Embodiments of FIGS. 6-8
In the embodiment of the invention illustrated in FIGS. 1-4, one or more imaging devices 110 are utilized to image a product as it drops and/or is at the product retrieval location 60. In the embodiment of the invention illustrated in FIGS. 6-8, an imaging device obtains an image of the selected product as the selected product moves along the path toward the product retrieval location. Since the embodiment of the invention illustrated in FIGS. 6-8 is generally similar to the embodiment of the invention illustrated in FIGS. 1-4, similar numerals will be utilize to designate similar components, the suffix letter “a” being associated with the numerals of FIGS. 6-8 in order to avoid confusion.
A vending machine 10a has a plurality of product dispensing devices 24a which are disposed in a housing, corresponding to the housing 12 of FIG. 1. The product dispensing devices 24a (FIG. 6) are operable to dispense a product 28a (FIG. 7) selected by a customer. In response to actuation of a selector switch keyboard 84a (FIG. 6) on a control panel 70a by a customer, a selected product 28a is moved from a product dispensing location 54a in one of the product dispensing devices 24a. As the helical conveyor elements 42a and 44a (FIG. 7) are rotated to dispense the selected product 28a from the dispensing location 54a, a next succeeding product 28a is moved to the dispensing location 54a. 
The selected product 28a moves downward away from its product dispensing device 24a along a path disposed between the trays 48a of products and a door, corresponding to the door 16 (FIG. 1), toward the product retrieval location 60a (FIG. 7). As the selected product is dropping downward along the path toward the product retrieval location 60a, the selected product 20a moves into an area 180 of interest in the manner illustrated schematically in FIG. 8. The area 180 of interest is disposed below the product dispensing devices 24a and is disposed above the product retrieval location 60a. The area 180 of interest extends between opposite sides of the vending machine 10.
In accordance with one of the features of this embodiment of the invention, when the selected product 28a is moving from a product dispensing device 24a to and through the area 180 of interest, one or more imaging devices 110a obtain images of the area of interest. These images are transmitted from the imaging devices 110a to the computer 114a (FIG. 6). The images are stored in an image data base 184 which forms part of the data base 120a. By using the comparator 116a to compare each of the images in turn with an image in the data base 184, the computer 114a can determine when a selected product moves into the area 180 of interest. When a product has moved into the area 180 of interest, the computer 114a provides an output which indicates that the selected product has been dispensed.
When the vending machine 10a (FIG. 6) has been restocked, that is, filled with products to be sold in the manner described in conjunction with the embodiment of the invention illustrated in FIGS. 1-4, the door of the vending machine is moved from an open position to a closed position. As the door is closed, a switch 148a (FIG. 6) is actuated. Actuation of the switch 148a indicates to the computer 114a that the door has been closed and restocking of the vending machine 10a completed.
When the door closes, the computer 114a initiates operation of the imaging devices 100a to obtain images of the products at the dispensing locations 54a (FIG. 7) in all of the product dispensing devices 24a (FIGS. 6 and 7). The imaging devices 100a have the same construction and mode of operation as the imaging devices 100 of the embodiments illustrated in FIGS. 3 and 4. The imaging devices 100a convert the visual (optical) images of the products 28a (FIG. 7) at the product dispensing location 54a in the product dispensing devices 24a to electrical signals. These electrical signals are representative of the images of the products 28a. 
The electrical signals are transmitted from the imaging devices 100a to the computer 114a (FIG. 6). The computer 114a initiates comparison of features of images represented by the electrical signals with data in the data base 120a. This comparison enables the computer 114a to determine the identity of each of the products 28a at each of the product dispensing locations 54a in the product dispensing devices 24a. 
To identify a product 28a at the dispensing location 54a, the aspect ratio of the image of the product to be identified is compared to the aspect ratios in the aspect ratio data base 126a. The image of the product 28a to be identified is compared to the color histograms in the color histogram data base 130a. The scale invariant features of the image are compared to the scale invariant feature data base 132a. 
Once the identity of each of the products 28a at the product dispensing locations 54a is determined, the price of each of product is determined from the product price database 122a. If the price display 36a for a particular product is not in agreement with the product price for the product which was identified as being present at the product dispensing location 54a, the product price display 36a is changed to indicate the correct product price.
After the vending machine 10a has been initialized identifying the next product 28a to be dispensed from each of the product dispensing locations 54a, the vending machine 10a is ready to serve customers. When a customer approaches a vending machine 10a, the products 28a at the product dispensing locations 54a in the product dispensing devices 24a are illuminated by a cabinet light assembly, corresponding to the cabinet light assembly 152 of FIG. 3. The customer views the products 28a (FIG. 7) and the price display 36 through a transparent window in the door of the vending machine 10a. 
After a customer has selected a particular product 28a, he inserts money to pay for the product into the control panel 70a (FIG. 6). Paper money is inserted at the bill validation insert 74a, coins are inserted at the coin insert 76a. A location may be provided for insertion for a credit/debit card. The customer is informed as to the amount of money which he has deposited into the vending machine by indicia at the credit display window 82a on the control panel 70a. 
Once the customer has deposited a requisite amount of money into the vending machine 10a, the customer manually actuates the selector switch keyboard 84a on the control panel 70a. The customer actuates keys on the selector switch keyboard to enter indicia indicative of the indicia 32a indicating the location of the selected product dispensing device 24a. The location of the product dispensing device 24a selected by a customer is transmitted from the selector switch keyboard 84a to the computer 114a. At this time, the display 88a may set forth indicia indicative characteristics of the selected product.
Once the keyboard 84a has been actuated to enter indicia corresponding to the indicia 32a indicating the location of the selected product 24a, the computer 114a effects operation of one or more motors 156a (FIG. 6) in the product dispensing device 24a at the selected product location indicated by the indicia 32a entered into the keyboard 84a of the control panel 70a. The motor 156a effects rotation of the helical conveyor elements 42a and 44a in the selected product dispensing device 24a. It should be understood that the product dispensing device 24a may have a different construction if desired.
Rotation of the helical conveyor elements 42a and 44a by a motor 156a (FIG. 6) moves the selected product 28a at the selected product dispensing location 54a off of the tray 48a (FIG. 7). The selected product 28a then drops downward along a vertical path extending from the product dispensing device 24a to the product retrieval location 60a. At the same time, rotation of the helical conveyor elements 42a and 44a advance the next succeeding product 28a from a storage location 52a to the product dispensing location 54a. Similarly, other products 28a disposed in storage locations 52a in the selected product dispensing device 24a are advanced toward the product dispensing location 54a by rotation of the helical conveyor elements 42a and 44a. 
As the selected product 28a falls downward along the path toward the product retrieval location 60a, the imaging devices 110a are operated to obtain images of the area 180 of interest (FIG. 7). As this occurs, the selected product moves into the area 180 of interest. The imaging device 110a (FIG. 6) is operated to obtain a visual image of the dispensed product. The visual image of the dispensed product 28a in the area 180 of interest is similar to the image illustrated schematically in FIG. 8. The imaging device 110 has the same construction and mode of operation as the imaging device 110 of the embodiment of FIG. 4. The imaging device 110a may be a video device.
The visual (optical) images obtained by operating the imaging device 110a while the selected product 28a moves toward and is the area 180 of interest compared with an image in the image database 184. The image in the image database 184 was taken without a product 28a in the area 180 of interest. The image in the data base 184 may be obtained before or during movement of the selected product 28a toward the area of interest. The comparator 116a compares the image of the area 180 of interest taken prior to movement of a product 28a into the area of interest (FIG. 7) with the image of the area of interest taken with the selected product 28a in the area of interest (FIG. 8).
When a comparison of the two images indicates that the selected product 28a has moved to the area 180 of interest, in the manner illustrated schematically in FIG. 8, a signal is transmitted from the comparator 116a to the computer 114a indicating that the selected product has been dispensed. The computer 114a then transmits a signal to the control panel 70a to change the credit display window 82a by deducting the cost of the dispensed product 28a from the amount of credit indicated at the credit display window. At the same time, the display 88a is changed to eliminate the display of the ingredients or other characteristics of the selected product 28a. At this time, the display 88a may set forth an advertisement for one or more of the products 28a in the vending machine 10a or may set forth a special price offer for one or more of the products 28a in the vending machine 10a. 
If desired, the image of the selected product 28a at the area 180 of interest, that is, the image illustrated schematically in FIG. 8, may be compared to data in the aspect ratio data base 126a, color histogram data base 130a and/or scale invariant feature data base 132a in an attempt to identify the selected product 28a. Of course, the selected product 28a will already have been identified with images obtained with the imaging devices 100a in the manner described in connection with the embodiment of the invention illustrated in FIGS. 1-4. It is contemplated that the imaging devices 100a, which image, products 28a at the dispensing location 54a, may be eliminated. If this is done, an image of the selected product 28a will be obtained only at the area 180 of interest. An attempt may be made to identify the selected product 28a from the image of the area 180 of interest (FIG. 8).
If the imaging devices 100a are eliminated, it is contemplated that the aspect ratio data base 126a, color histogram data base 130a, scale invariant feature data base 132a and product priced data base 122a may be eliminated. If this is done, the data base 120 would contain only the image data base 184. Although it is believed that some vending machines may be constructed with only the imaging devices 110a to determine when a selected product 28a has been dispensed, it is contemplated that other vending machines will be constructed with both the imaging devices 100a and the imaging devices 110a. 
To facilitate imaging of a selected product 28a in the area 180 of interest, a stripe 188 extends across the area of interest. The stripe 188 is a long narrow section which differs in appearance from adjoining areas in the vending machine 10a. The stripe 188 may have a uniform color or may have a plurality of different colors. The stripe 188 may be formed of a light reflective material. If desired, sources of light may be included in the stripe 188.
The horizontal stripe 188 extends from the left (as viewed in FIG. 8) edge of the area 180 of interest to the right edge of the area of interest. The area 180 of interest is disposed below all of the product dispensing devices 24a in the vending machine 10a and is disposed above a shelf 192 at the product retrieval location 60a (FIGS. 7 and 8). The area 180 of interest extends from an inner side surface of a left wall of a housing for the vending machine 10a to an inner side surface of a right wall of the housing for the vending machine.
The stripe 188 extends approximately through the center of the area 180 of interest. Therefore, the imaging device or devices 110a can obtain an image of a selected product 28a as it enters and/or leaves the area 180 of interest. Thus, the imaging device 110a may obtain an image of a selected product 28a as a lower portion of the selected product moves into the area 180 of interest. In addition, the imaging device 110a may obtain an image of the selected product 28a as an upper portion of the selected product moves out of the area 180 of interest. The imaging device or devices 110a may obtain an image of a selected product at any point along its path of movement through the area 180 of interest. If desired, the stripe 188 may be omitted.
As is illustrated schematically in FIG. 8, the path of movement of a selected product 28a through the area 180 of interest is disposed between the stripe 188 and the imaging device or devices 110a. Therefore, the imaging devices 110a obtain an image of the product 28a with the stripe 188 as background for the selected product. This facilitates determining when the selected product 28a is in an image transmitted from the imaging device or devices 110a to the computer 114a and compared with an image in the database 184 by the comparator 116a. 
The image or images in the data base 120a are obtained before the selected product has moved into the area 180 of interest. Therefore, the selected product 28a will not be shown in an image in the image database 184. Therefore, a comparison of the image obtained as a selected product 28a moves through the area 180 of interest with an image in the image data base 184 will result in the controls 106a sensing at least a portion of the selected product 28a in the area 180 of interest. This comparison is facilitated by having the stripe 188 extend across the entire width of the area 180 of interest to provide a contrasting background against which the selected product 28a is imaged (FIG. 8).
The illustrated stripe 188 has alternating light areas 196 (FIG. 8) and dark areas 198. The alternating light and dark areas 196 and 198 provide a contrasting background against which a selected product 28a can be viewed in an image obtained by an imaging device 110a. However, if desired, the stripe 188 may be formed with a continuous light area 196 or a continuous dark area 198 throughout the length of the stripe.
In the illustrated embodiment of the invention, the stripe 188 is formed by a strip of tape which extends across the area 180 of interest. It is contemplated that the stripe 188 may be formed in a different manner if desired. For example, a light area 196 of the stripe may be formed by light emitting diodes with an associated lens. The dark areas 198 may be formed by paint on a structural component of the vending machine 10a. As was previously mentioned, the stripe 188 may be omitted if desired.
In the unlikely event that the imaging device or devices 110a (FIG. 6) do not obtain an image of a selected product 28a at the area 180 of interest (FIG. 8), the computer 114a receives an indication of malfunctioning of the selected product dispensing device 24a. The computer 114a then effects operation of the motor 156a associated with the selected product dispensing device 24a with a jogging or intermittent operation in a further effort to dispense the selected product 28a. If this intermittent operation of the motor 156a is successful, the intermittent or jogging operation of the motor 156a is interrupted when the imaging device or devices 110a are able to obtain a visual image of the selected product 28a as the selected product moves through the area 180 of interest.
If the intermittent or jogging operation of the motor 156a is ineffective to cause the selected product dispensing device 24a to dispense the selected product 28a, the computer 114a changes the display window 88a to indicate to the customer that another selection is to be made. The computer 114a gives the customer credit for money that has already been deposited in the vending machine 10a and allows the customer to make a selection of a product 28a of equal or lesser cost. Of course, if a product of lesser cost is selected, the computer 114a effects operation of the vending machine 10a to refund the excess amount of money which the customer deposited. Alternatively, the computer 114a could immediately give the customer a refund if a selected product 28a is not dispensed.
The computer 114a periodically activates the transmitter 136a (FIG. 6) to transmit a signal 138a to a base or remote location. The signal 138a indicates the identity of the products which have been dispensed and indicates the prices of the products. This enables personnel at the base or remote location to determine how much money has been deposited in the vending machine 10a and to determine what products need to be brought to the vending machine in order to restock the vending machine. The transmitter 136a may be of either a radio or telephone type. Of course, other types of transmitters may be utilized if desired. If desired, the computer 114a could activate the transmitter 136a to transmit data in response to a signal from a base station.
One or more imaging devices 110a may be utilized to obtain visual images of the area 180 of interest. For example, the field of view of a single imaging device 110a may be large enough to include the entire area 180 of interest. This single imaging device 110a may be mounted on the door of the vending machine 10a in the manner previously explained in conjunction with the embodiment of the invention illustrated in FIGS. 1-4. Alternatively, the single imaging device 110a may be mounted on the housing or other component of the vending machine 10a. For example, the imaging device 110a may be mounted on the inside of an upper or top wall or panel of a housing, corresponding to the housing 12 of FIG. 1.
It is contemplated that a plurality of imaging devices 110a may be provided to obtain an image of the selected product 28a in the area 180 of interest. For example, a first imaging device 110a may be positioned so as to obtain an image of a central portion of the area of interest. A second imaging device 110a may be mounted so as to obtain a view of the left portion of the area of interest, including a small portion of the central portion of the area of interest. In addition, a third imaging device 110a may be provided to obtain a visual image of a right portion of the area 180 of interest and a portion of the central portion of the area of interest. It is contemplated that any desired number of imaging devices may be utilized to obtain images which are compared to images in the image data base 184.
The comparator 116a compares an image or images taken by one or more imaging devices 110a to detect the vending of a selected product 28a. Thus, the imaging devices 110a transmit images of the area 180 of interest to the controls 106a as a selected product 28a moves downward toward the product retrieval location 60a and before the selected product moves into the area of interest. This will result in the images of the area 180 of interest being transmitted to the controls 106a. These images will have the composition illustrated schematically in FIG. 7.
Each image is compared to the immediately preceding image to determine whether or not the selected product 28a has moved to the area 180 of interest. As long as the image is sent from the imaging devices 110a to the computer 114a are taken before the selected product 28a arrives at the area 180 of interest, the images will have the composition illustrated schematically in FIG. 7. A comparison by the comparator 116a of the images having the same composition will indicate to the computer 114a that the selected product 28a has not moved downward along its path toward the product retrieval location 60a to the level of the area 180 of interest. The area 180 of interest is at a level which is lower than the level of all of the product dispensing devices 24a in the vending machine 10a. 
When the selected product 28a has moved downward to the area 180 of interest, in the manner illustrated schematically in FIG. 8, the selected product 28a is disposed between the imaging device or devices 110a and the stripe 188. Therefore, at this time, when an image of the area 180 of interest is obtained by operation of an imaging device 110a, the selected product 28a will block the view of an imaging device 110a of a portion of the stripe 188. This results in the stripe being interrupted in the image obtained with the imaging device 110a. When the image obtained with an imaging device 110a of the area 180 of interest with the selected product 28a in the area of interest (as shown in FIG. 8), the image will differ from the immediately preceding image obtained by the imaging device 110a. 
As the selected product 28a moves into the area 180 of interest, the lower portion of the product moves into the area of interest. If the image of the selected product is obtained at this time, the comparator 116a and computer 114a will determine that the upper perimeter portion of the most recent image is different than the upper perimeter portion of the immediately preceding image. Therefore, the computer 116a will provide an output which indicates that a selected product has been dispensed.
When the image obtained by an imaging device 110a of an area 180 of interest with the selected product 28a in the area of interest is compared with an immediately preceding image in which the selected product is not in the area of interest, the difference between the two images will result in the comparator 116a transmitting a signal to the computer 114a indicating that the selected product 28a has moved into the area 180 of interest and will fall downward onto the shelf 192. This results in the computer 114a sending a signal to the control panel 70a indicating that the selected product has been vended. At this time, the credit display 82a will be modified to indicate a reduction in the customer's credit as a result of the successful vending of the selected product 28a. Of course, if for some unforeseen reason there is not a successful vending of a selected product 28a by the vending machine 10a, the images transmitted from the image device or devices 110a to the computer 114a will all be the same and the comparator 116a will not provide an output signal to the computer 114a indicating that a product has been successfully vended.
In the foregoing description, each image of the area 180 of interest obtained by an imaging device 110a is compared with the immediately preceding image of the area of interest. However, it is contemplated that the comparator 116a may compare an image transmitted from an imaging device with any one of the images taken before the image presently being transmitted from the imaging device to the computer 114a. For example, an image obtained by the imaging device 110a may be compared with each of the preceding five images transmitted from the imaging device 110a to the computer 114a. Alternatively, the image obtained by operation of an imaging device 110a may be compared only with the fifth preceding image in a series of preceding images.
Since the image of the area 180 of interest remains substantially constant until a selected product 28a enters the area of interest, it is contemplated that all of the images obtained from the imaging devices 110a may be compared with the same image of the area 180 of interest. For example, a base or reference image of the area 180 of interest may be stored in the image data base 184. This base or reference image will be compared with each of the images obtained by the imaging devices 110a. The comparator 116a will detect a change in the images obtained by operation of the imaging devices from the base or reference image only when a selected product 28a has moved into the area 180 of interest. The base or reference image may be provided in the data base 184 before the vending machine 10a is moved to a location where it is to vend products 28a. 
If a plurality of imaging devices 110a are utilized to obtain an image of a product as the product moves through the area 180 of interest, an image from each imaging device may be compared with a separate image in the data base. Thus, an image of the area 180 of interest obtained with a first one of the imaging devices 110a would be compared with an image in the data base 184 of the area 180 of interest obtained with the first one of the imaging devices 110a. Similarly, an image of the area of interest obtained with a second one of the imaging devices 110a would be compared with an image in the data base 184 of the area of interest obtained with the second one of the imaging devices 110a. Alternatively, images of the area 180 of interest obtained with all of the imaging devices 110a may be compared with the same image in the data base 184.
The imaging devices 110a are utilized to deter theft by being operated before and/or after dispensing of a selected product 28a. When the imaging devices 110a are operated before and/or after dispensing of a product 28a, a comparison of images obtained by the imaging devices should indicate that the images are all the same. If the comparison of images shows a change in one or more of the images, this would indicate movement of a foreign article into the area of interest. Such a foreign article may be moved into the area of interest during an attempt to steal products 28a from the vending machine 10a. In response to the change in the images obtained with movement of a foreign article into the area 180 of interest, the vending machine 10a may shut down and/or a base location notified with the transmitter 136a. If desired, an alarm may sound and/or lights may flash.
Conclusion
The present invention provides a vending machine 10 having a plurality of product dispensing devices 24. Each of the product dispensing devices 24 holds a next product 28 to be dispensed from the dispensing device and a plurality of products which are located at product storage locations 52 in the product dispensing device. The products at the storage locations are sequentially moved to the product dispensing location.
When a customer selects a product 28, the product is moved from one of the product dispensing locations 54 to a product retrieval location 60 where the customer has access to the selected product. The selected product moves from one of the product dispensing devices 24 along a path which extends to the product retrieval location. In accordance with one of the features of the present invention, an image of the selected product 28 is obtained as the selected product moves along the path toward the product retrieval location 60.
As the selected product 28 moves along the path toward the product retrieval location, a plurality of images of a selected portion 180 of the path are sequentially obtained and transmitted to a data base 120. Each of the images (FIG. 8) is compared to an image (FIG. 7) in the data base 120 to determine when a product 28 has moved into the image. In response to movement from the product 28 into the image, controls 106 in the vending machine 10 determine that a product has moved to the product retrieval location.
The present invention has a number of different features. These features may be utilized together as disclosed herein. These features may be utilized separately and/or in various combinations with each other or the prior art.

## Claims

1. A method comprising the steps of providing a vending machine having a plurality of product dispensing devices and a product retrieval location where a customer has access to a selected product, moving a selected product from one of the product dispensing devices along a path which extends from the one product dispensing device to the product retrieval location, providing a stripe which extends across the path along which the selected product moves from the one product dispensing device to the product retrieval location, and obtaining an image of the selected product as the selected product moves along the path toward the product retrieval location, said step of obtaining an image of the selected product as the selected product moves along the path is performed with a portion of the selected product disposed between the stripe and the imaging device.

2. A vending machine for use in vending products, said vending machine comprising a housing, a plurality of product dispensing devices disposed in said housing, said product dispensing devices being operable to dispense a product selected by a customer, a product retrieval location where the customer has access to a selected product dispensed by one of said product dispensing devices, said product retrieval location being disposed in said housing at a location which is lower than a location where said product dispensing devices are disposed in said housing, an area of interest disposed in said housing at a location which is lower than the location where said product dispensing devices are disposed in said housing and which is higher than the location where said product retrieval location is disposed in said housing, said area of interest being disposed along a path which a product moves from one of said product dispensing devices to said product retrieval location, a stripe extends across said area of interest in a direction transverse to the path along which a product moves from one of said product dispensing devices, and an imaging device disposed in said housing, said imaging device being operable to obtain an image of said area of interest as the product moves away from one of said product dispensing devices through said area of interest toward said product retrieval location, said imaging device being operable to obtain an image of said area of interest with at least a portion of the product disposed between said stripe and said imaging device.

3. A vending machine as set forth in claim 2 wherein said stripe includes a series of relatively light and dark areas.

4. A vending machine as set forth in claim 2 wherein said imaging device is continuously operable to obtain images of said area of interest, said vending machine including controls which are disposed in said housing and provide an output signal in response to a change in the image obtained by operation of said imaging device.

5. A vending machine as set forth in claim 2 wherein said imaging device is operable to obtain images of said area of interest prior to and after a product moves through said area of interest to enable said imaging device to be utilized to deter theft of products from said vending machine.