WO2017216536A1

WO2017216536A1 - Product verification system

Info

Publication number: WO2017216536A1
Application number: PCT/GB2017/051710
Authority: WO
Inventors: Mark Lynch; Lee RAGG
Original assignee: Fairfield Labels Limited
Priority date: 2016-06-15
Filing date: 2017-06-13
Publication date: 2017-12-21
Also published as: GB2551489A; GB201610411D0

Abstract

A product verification system is described that comprises a camera (18) operable to capture an image (18a) of a first product (12a) as the first product (12a) is moved past the camera (18), and to subsequently capture an image (18a) of a second, immediately subsequent product (12b) as the second product (12b) is moved past the camera (18), an image comparator (20) operable to compare at least one aspect of the captured image of the first product (12a) with an expected image to verify that a characteristic of the first product (12a) is correct, wherein the image comparator (20) operates substantially in real-time and the verification operation undertaken in relation to the captured image of the first product (12a) is complete before the captured image of the second product (12b) is available for verification by the image comparator (20).

Description

Product Verification System

This invention relates to a system operable to verify that characteristics of a product passing along a production line fall within acceptable ranges. The system is particularly suited to use in a manufacturing or packaging plant in which products, for example beverages or foodstuffs, are manufactured and/or packaged, the system being operable to confirm that characteristics of the product and/or its packaging satisfy the requirements of a customer. However, it may be used in a number of other applications.

Systems for use in verifying that certain characteristics of products passing along a production line meet an acceptable level are well known. By way of example, systems are known in which a bar code reader or the like is located adjacent a production line and is operable to scan the bar codes provided upon the packaging of products as they pass along the production line. By scanning or reading the bar codes in this manner, an operator of the production line may be satisfied that the products include a readable bar code.

It is desirable for other characteristics of the product and/or its packaging to be verified. By way of example, it may be desired, in some circumstances to check that the printing of the bar code meets certain quality standards, or to check that a best before date, or other date, lot number or other code is printed upon the packaging in a predetermined area. Where such a date or code is printed, then it may be desirable to be able to check that the printed date matches an actual best before date of the product. It will be appreciated that these represent just examples of a wide range of characteristics of a product or its packaging that it may be desired to be able to verify.

Whilst verification of such parameters may be desired, existing systems are unable to inspect and validate the characteristics of each and every product and/or its packaging passing along a production line whilst the production line is operating at its normal operating speed. As slowing down the operating speed of the production line is not desirable, known systems typically only allow verification of a small number of parameters or characteristics of the products, and only allow verification to be undertaken in relation to selected ones of the products on the production line. By way of example, every one hundredth, say, product passing along the production line may be inspected, and this inspection may be undertaken away from the production line. Whilst this avoids slowing down the production line, in the event that the inspection identifies that there is a fault with the inspected product, then the operator must assume that all products on the production line since the last one that was inspected and for which the result of the inspection was acceptable may also be faulty. Since these products may be faulty, then typically they will be disposed of, although in some cases it may be possible for the detected fault to be rectified. In the case where only every one hundredth product is tested, it will be appreciated that the number of products that must be disposed of will be in excess of one hundred. Clearly, this level of wastage is undesirable.

Failure to identify and remove faulty products before dispatch to a customer can lead to product recalls, fines, loss of contracts and other penalties. Accordingly, it is important for a manufacturer to ensure that such faults are identified and the faulty products either corrected or removed and disposed of, rather than being passed on to the customer.

It is an object of the invention to provide a system whereby a number of characteristics of a product can be inspected and verified, in which each and every product passing along a production line can be inspected, and in which the inspection does not significantly require the operating speed of the production line to be slowed.

According to the present invention there is provided a product verification system comprising a camera operable to capture an image of a first product as the first product is moved past the camera, and to subsequently capture an image of a second, immediately subsequent product as the second product is moved past the camera, an image comparator operable to compare at least one aspect of the captured image of the first product with an expected image aspect to verify that a characteristic of the first product is correct, wherein the image comparator operates substantially in real-time and the verification operation undertaken in relation to the captured image of the first product is complete before the captured image of the second product is available for verification by the image comparator.

The at least one aspect of the captured image that is verified preferably includes at least one of (a) checking that the product contains a bar code and that the bar code is correct; (b) checking that the print quality of the bar code is acceptable; (c) checking that the product has a best before date, other date, lot number or other code printed in a specified area thereof; (d) checking that the printed best before date, other date, lot number or other code matches an expected date or code; (e) checking that a label is correctly orientated; (f) checking that the product and/or packaging is of an expected shape or size; (g) where the product is a liquid filled container, checking that a cap and/or seal is correctly fitted; and (h) checking that the level of the liquid within the container falls within an acceptable range. It will be appreciated that this list is not exhaustive, and that arrangements are possible in which other characteristics than those mentioned above are verified. Furthermore, depending upon the product under inspection, only some of the characteristics mentioned above may be verified.

The image comparator may undertake several comparisons between the captured image and the expected image simultaneously or substantially simultaneously, the comparisons being undertaken in parallel. It will be appreciated that, in this manner, comparison speed may be increased, allowing a number of individual comparison operations to be undertaken in the time available.

It will be appreciated that such an arrangement allows a number of comparison operations to be undertaken to verify a number of characteristics, parameters or aspects of a product and/or its associated packaging, the system allowing the comparison operations to be undertaken in relation to each and every product passing along the production line. As the comparison operation is undertaken rapidly, it will be appreciated that the operation may be undertaken without requiring the operating speed of the production line to be slowed. Importantly, the arrangement allows the quality with which applied codes have been printed to be checked, to ensure that standards applied by customers are met, and hence that penalties for supplying below quality products are avoided, and allows it to be ensured that the applied codes are correct, correctly relating to the associated products. This is important where a product line is used to manufacture a number of different products, for example foodstuffs with different ingredients, or different formulations, ensuring that the codes associated with the product accurately match the relevant product.

Conveniently, the system further includes an illumination arrangement, operable to illuminate the products, the images of which are being captured by the camera. It will be appreciated that by brightly illuminating the products, the quality of the captured image may be enhanced, simplifying the comparison operation and increasing the accuracy with which it may be performed. Depending upon the nature of the product, the illumination arrangement may be operated to illuminate the product with a selected colour of light. In this manner, the clarity with which, for example, a best before date printed onto the packaging shows up may be enhanced to achieve further enhancements in the accuracy with which the comparison operation can be undertaken.

The system may further include a warning device to provide an audible and/or visible warning in the event that a fault has occurred. If desired, it may further be arranged to interrupt operation of the production line, or may be operable to control a device to remove faulty products from the production line.

Parts of the system may be located within a housing. Preferably, the housing carries the warning device. It may further include a control panel, for example in the form of a touch screen display, whereby an operator can control the operation of the system and, for example, input information regarding the products being inspected, for example to input a best before date that the system then uses to check that each and every product on the product line contains the correct date. The expected image will typically be made up of information input via the control panel. However, it could, if desired, be based upon an image captured by the camera of a product that has been manually verified as being correct.

The invention further relates to a corresponding product verification method comprising using a camera to capture an image of a first product as the first product is moved past the camera, and to subsequently capture an image of a second, immediately subsequent product as the second product is moved past the camera, comparing at least one aspect of the captured image of the first product with an expected image aspect to verify that a characteristic of the first product is correct, wherein the image comparison and verification is undertaken substantially in real-time, the verification operation undertaken in relation to the captured image of the first product being complete before the captured image of the second product is available for verification by the image comparator.

The invention will further be described, by way of example, with reference to the accompanying drawings, in which:

Figures 1 is a diagrammatic view illustrating a system in accordance with an embodiment of the invention;

Figure 2 is a view illustrating part of the system, in use; and

Figure 3 is a view illustrating another part of the system.

Referring to the accompanying drawings, a product verification system 10 is shown, the system 10 being operable to verify that aspects of each and every product 12a, 12b, 12c passing along a production line 14 meet predetermined requirements. The system 10 comprises a lighting arrangement 16 operable to illuminate at least one side of the products 12, and a digital camera 18 operable to capture an image 18a of each product 12 as the products pass, in turn, in front of the camera 18. The camera 18 may be operable to output a continuous image of the products 12 as the products 12 pass in front of the camera 18. In such an arrangement, the image output from the camera 18 is converted into a series of individual images, each being representative of a single one of the products 12. Alternatively, it may be arranged to output a series of discrete images, one for each of the products 12 as they pass along the production line 14.

The lighting arrangement 16 may take a range of forms. By way of example, it could take the form of an array of LEDs or the like. Preferably, the lighting arrangement is operable to brightly illuminate the parts of the product that are imaged using the camera 18. The lighting arrangement may be operable to emit light of a wavelength or wavelength range tuned to the product in order to maximise the contrast between, for example, a background colour and a colour printed onto the product packaging to aid discrimination, checking and verification of the printed matter as set out below. Depending upon the application in which the invention is employed, the lighting arrangement may be controllable in such a manner as to vary the illumination to permit such tuning.

The system 10 further comprises an image comparator 20 operable to receive the images 18a in turn, to analyse the images 18a and determine whether aspects of the images 18a match specific criteria. Discrepancies between the aspects of the images 18a and the predetermined criteria are taken to indicate that there is a fault with the product 12 under inspection.

The image comparator 20 is operable to undertake a number of comparison operations substantially simultaneously, the comparison operations being undertaken in parallel with one another. As shown in Figure 1, therefore, the image comparator 20 includes a first comparison tool 20a operable to compare the image 18a with an expected image to identify whether a predetermined part of the product shown in the image has the appearance of a bar code. If it has the appearance of a bar code then the first tool outputs a signal indicating that the product is acceptable. If no bar code is identified in the predetermined part, then the first tool outputs a fault signal. The fault signal is relayed from the comparator 20 to a control unit 22 which, in turn, upon receipt of the fault signal, triggers the operation of a warning device 24, for example in the form of flashing lights or an audible alarm. Depending upon the application in which the invention is used, the control unit 22 may further be operable to interrupt the operation of the production line 14 to allow the cause of the fault to be remedied to avoid the production of a number of similarly faulty products.

Whilst the first tool 20a mentioned above simply checks that a bar code is present, the tool 20a could be more complex than this. By way of example, it may operate to compare the detected bar code with an expected bar code, for example input to the system 10 via a control panel 26 in the form of a touch screen or the like mounted upon a housing 28 within which the control unit 22 and comparator 20 are located, and upon which the warning device 24 is mounted. In this manner, the system 10 not only checks that a bar code is present, but further confirms that the correct bar code is present.

The first tool 20a of the system 10 may further be operable to ensure that the quality of the detected bar code meets predetermined requirements. By way of example, checks may be undertaken to ensure that the contrast between the dark and light bars of the code meets certain requirements, and to ensure that the level of defects in the printed bar code is lower than a predetermined level so as to ensure that the bar code is of good long-term readability. It may return a grade based upon these measured parameters, and output a fault signal in the event that the grade is lower than a predetermined grade.

The comparator 20 further includes a second comparator tool 20b operating in parallel with the first tool 20a. The second tool 20b is operable to identify if text is present in a predetermined area of the product image 18a. By way of example, where the product contains a region upon which a best before date or other date or code information is to be printed, the tool 20b operates to identify whether text is present within that region. Upon identifying that text is present in that region, the identified text is passed through an optical character recognition sub-tool 30, the output of which is compared with an expected text string previously input via the control panel 26. Discrepancies between the expected text and the identified text output from the optical character recognition sub-tool 30 result in the generation of a fault signal that is supplied to the control unit 22 to trigger warnings, etc, to the production line operator and/or interrupt the production line 14.

As the first tool 20a and the second tool 20b operate in parallel, it will be appreciated that all of the comparison operations may be undertaken quickly. Accordingly, by the time that an image of the second product 12b is ready for analysis, all of the comparison operations required to be undertaken in connection with the image of the first product 12a will have been completed, and by the time the image of the third product 12c is ready for analysis, the comparisons under taken in connection with the image of the second product 12b will have been completed. It will be appreciated, therefore, that the system 10 is able to conduct a plurality of different comparison operations on the products 12 moving along the product line 14, the comparison operations being undertaken on each and every product 12, without requiring the operating speed of the production line 14 to be slowed to an unacceptable extent.

Whilst the system described so far only undertakes comparisons to ensure that a bar code is present (and optionally that it meets other requirements) and that a best before date or other text is present and correct, the system may, as illustrated, be arranged to undertake other comparison operations. Accordingly, as shown, a third comparator tool 20c is present, arranged in parallel with the first and second tools 20a, 20b. The third tool 20c may, for example, be arranged to identify the locations of two corners of a label applied to the product, and to ensure that the positions of the corners relative to the outline of the product meets certain criteria. By way of example, it may be arranged to verify that the label is not skewed. In the event that it is detected that the label is skewed, then a fault signal is generated. Other tests or comparisons that may be undertaken include comparing the outline of the product in the image with an expected shape, to identify whether the product has been damaged, for example dented, during the production, or to identify whether the product is of an expected size. Where the product is a beverage or liquid container, then the third tool 20c may be operable to identify whether a cap has been fitted as expected, to check that a fill level of the container meets expectations or to conduct other tests. Other tests that can be conducted include counting whether a predetermined number of product elements are present within the image of a product. For example, the system could be used to check that a box of chocolates contains a predetermined number of chocolates by counting the number present before a lid is fitted to the box. Alternatively, it may be arranged to check for the presence or absence of product elements at specific locations within the image. Obviously, if required, additional tools may be provided within the comparator 20 to undertake these tests. The nature of such tests or inspections may depend upon the nature of the products under inspection and the requirements of the customer.

As set out hereinbefore, the arrangement of the invention has the advantage that each and every product passing along the production line is inspected and verification checks are undertaken to ensure that appropriate requirements are met. By checking each and every product, wastage is reduced and the risk of faulty products being supplied to the customer, with the associated risk of product recalls, fines or the like, is reduced. By conducting a number of different checks on the product, it can be ensured that the product complies with a number of customer specified criteria. By conducting the comparisons necessary to verify that the criteria are satisfied in parallel, it will be appreciated that the verification process can be undertaken at a sufficiently high speed that there is no need for the operating speed of the production line to be reduced to allow the verification process to be undertaken.

The verification operation may be undertaken at any appropriate point in the production line. For example, individual products may be checked prior to packaging with larger cartons. However, if desire, it may be employed elsewhere in the manufacturing process. Indeed, there may be circumstances in which two or more verification processes are undertaken at different points in the manufacturing process.

Whilst a specific system is described hereinbefore, it will be appreciated that a wide range of modifications and alterations may be made thereto without departing from the scope of the invention as defined by the appended claims, and all such variants or modifications fall within the scope of this application.

Claims

CLAIMS:

1. A product verification system comprising a camera operable to capture an image of a first product as the first product is moved past the camera, and to subsequently capture an image of a second, immediately subsequent product as the second product is moved past the camera, an image comparator operable to compare at least one aspect of the captured image of the first product with an expected image to verify that a characteristic of the first product is correct, wherein the image comparator operates substantially in real-time and the verification operation undertaken in relation to the captured image of the first product is complete before the captured image of the second product is available for verification by the image comparator, wherein the said characteristic relates to the quality and/or accuracy of a code applied to the first product.

2. A system according to Claim 1, wherein the at least one aspect of the captured image that is verified includes checking that the product contains a bar code and that the bar code is correct.

3. A system according to Claim 1 or Claim 2, wherein the at least one aspect of the captured image that is verified includes checking that the print quality of the code is acceptable.

4. A system according to any of Claims 1 to 3, wherein the code comprises an alphanumeric sequence comprising a best before date, other date, lot number or other code printed in a specified area on the product, and the at least one aspect of the captured image that is verified includes checking for the presence of the best before date, other date, lot number or other code.

5. A system according to any of Claims 1 to 4, wherein the code comprises an alphanumeric sequence comprising a best before date, other date, lot number or other code printed in a specified area on the product, and the at least one aspect of the captured image that is verified includes checking that the best before date, other date, lot number or other code matches an expected date or code.

6. A system according to any of the preceding claims, further comprising (a) checking that a label is correctly orientated; (b) checking that the product and/or packaging is of an expected shape or size; (c) where the product is a liquid filled container, checking that a cap and/or seal is correctly fitted; or (d) checking that the level of the liquid within the container falls within an acceptable range.

7. A system according to any of the preceding claims, wherein the image comparator undertakes several comparisons between the captured image and the expected image simultaneously or substantially simultaneously, the comparisons being undertaken in parallel.

8. A system according to any of the preceding claims, wherein the comparator includes a plurality of comparator tools operable to conduct different comparator operations independently of one another.

9. A system according to Claim 8, wherein the comparator tools operate in parallel.

10. A system according to any of the preceding claims, further including an illumination arrangement, operable to illuminate the products, the images of which are being captured by the camera.

11. A system according to any of the preceding claims, further comprising a warning device to provide an audible and/or visible warning in the event that a product fault has been detected.

12. A system according to any of the preceding claims, wherein parts of the system are located within a housing.

13. A system according to Claim 12, wherein the housing carries the warning device.

14. A system according to Claim 12 or Claim 13, wherein the housing includes a control panel whereby an operator can control the operation of the system.

15. A system according to Claim 14, wherein the control panel comprises a touch screen display.