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Title:
BAGGAGE TRACKING SYSTEM
Document Type and Number:
WIPO Patent Application WO/2010/067132
Kind Code:
A2
Abstract:
A baggage tracking system (200) uses an array of cameras (212) to image a bag tag (128) and thereby route a bag (132) with a sort allocation computer (114) in the event that a barcode on the tag (128) is unreadable. The system can also identify and create baggage source messages with reference to various databases (212, 214, 216, 218, 220).

Inventors:
BEHAN, Max (3 Shakespeare Cottages, Park LaneSnitterfield, Stratford-upon-Avon Warwickshire CV37 0LS, GB)
Application Number:
GB2009/051704
Publication Date:
June 17, 2010
Filing Date:
December 14, 2009
Export Citation:
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Assignee:
DIRECT RADIO RESPONSE LTD (3 Shakespeare Cottages, Park LaneSnitterfield, Stratford-upon-Avon Warwickshire CV37 0LS, GB)
BEHAN, Max (3 Shakespeare Cottages, Park LaneSnitterfield, Stratford-upon-Avon Warwickshire CV37 0LS, GB)
International Classes:
B64F1/36; G06K7/00; G06K9/03; G06K9/72
Attorney, Agent or Firm:
WITHERS & ROGERS LLP (Goldings House, 2 Hays Lane, London SE1 2HW, GB)
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Claims:
Claims

1. A baggage directing apparatus comprising a computer having a memory and a processor, the system being configured to communicate with a baggage router apparatus, the baggage router apparatus being configured to direct baggage from a first location to a second location, wherein the computer is configured to generate by calculation at least a partial baggage source message from an image of a bag tag stored in the memory using the processor and communicate the at least partial baggage source message to the baggage router apparatus for use in directing baggage.

2. A baggage directing apparatus according to claim 1 further comprising image capture apparatus proximate the baggage router apparatus, which image capture apparatus is configured to capture the image of the bag tag.

3. A baggage directing apparatus according to claim 2 in which the image capture apparatus is a camera.

4. A method of routing an item of baggage comprising the steps of: providing a computer having a memory and a processor, using the processor to calculate an at least partial baggage source message from an image of the bag tag stored in the memory, communicating the at least partial baggage source message to a baggage router apparatus to route the item of baggage using the at least partial baggage source message.

5. A method of routing an item of baggage according to claim 4 further comprising the steps of: providing an image capture apparatus proximate the baggage router apparatus, and, using the image capture apparatus to capture the image of the bag tag.

6. A baggage directing apparatus comprising: a computer configured to access a data memory, the data memory having a database comprising a plurality of entries stored therein, each entry comprising a baggage source message and an associated unique baggage identifier corresponding to a bag tag, the computer having an image memory and a processor, wherein the computer is configured to: extract tag data from an artefact of an image of a bag tag stored in the image memory using the processor, which bag tag is unreadable by a barcode scanner, identify a relevant entry in the database corresponding to the bag tag which is unreadable by a barcode scanner using the tag data, look up a baggage source message corresponding to the bag tag which is unreadable by a barcode scanner, and, communicate the baggage source message to the baggage router apparatus to enable the baggage router apparatus to direct the baggage.

7. A baggage directing apparatus according to claim 6 in which the step of identifying the relevant entry comprises the step of comparing the tag data to a plurality of entries in the database and determining a best match entry from the database, the the relevant entry being the best match entry.

8. A baggage directing apparatus according to claim 6 or 7 in which the artefact comprises the unique identifier in alphanumeric form.

9. A baggage directing apparatus according to any of claims 6 to 8 in which the artefact comprises a partial bar code.

10. A baggage directing apparatus according to claim 9 in which the artefact comprises at least two partial barcodes and the step of identifying the relevant entry comprises the step of combining the at least two partial barcodes to determine the unique identifier.

11. A baggage directing apparatus according to claim 10 in which the at least two partial barcodes are parts of identical barcodes.

12. A baggage directing apparatus according to claim 11 in which the identical barcodes are differently oriented.

13. A baggage directing apparatus according to any of claims 6 to 12 in which the artefact comprises alphanumeric information containing passenger and / or route information.

14. A baggage directing apparatus according to any of claims 6 to 13 in which the artefact comprises the format of the bag tag.

15. A baggage directing apparatus according to any of claims 6 to 14 in which the step of identifying comprises the step of accessing a further database.

16. A baggage directing apparatus according to claim 15 in which the further database comprises a flight schedule.

17. A baggage directing apparatus according to any of claims 6 to 16 in which in the event that a relevant entry cannot be identified, the computer is configured to calculate at least a partial baggage source message from the artefact (and preferably also using external data sources) using the processor and communicate the at least partial baggage source message to the baggage router apparatus for use in directing baggage.

18. A baggage directing apparatus according to any of claims 6 to 17 in which the data memory is stored in a single apparatus, for example the system, the computer or the router apparatus.

19. A baggage directing apparatus according to any of claims 6 to 17 in which the data memory is stored in multiple apparatus, for example the system, the computer and / or the router apparatus.

21. A method of routing an item of baggage comprising the steps of: providing a baggage router apparatus, providing a data memory storing a first data set having a plurality of entries, each entry having a baggage source message and an associated unique baggage identifier corresponding to a bag tag allocated to an item of baggage, providing a computer having a memory and a processor, the computer being configured to access the data memory and to communicate with the router apparatus, providing an image of a bag tag on the memory, using the processor to extract a second data set from an image of the bag tag stored on the image memory using the processor, using the processor to compare the second data set and the first data set to determine a best match entry from the first data set, and, communicating the identity of the baggage source message of the best match entry to the baggage router apparatus to enable the baggage router apparatus to direct the baggage.

22. A computer program comprising a set of instructions which when run on a computer of a baggage directing apparatus converts the system to a system according to any preceding claim.

Description:
Baggage tracking system

The present invention is concerned with the correct operation of baggage routing apparatus in particular relating to identification and tracking of baggage items present routed by the apparatus. More particularly, the present invention is concerned with airport baggage transport and directing apparatus.

When an item of baggage is checked in at an airport check-in desk by a passenger, an operator uses a check-in computer to create a unique 10 digit alphanumeric baggage identifier string. This string is known as a "licence plate".

In addition a first data set is created comprising routing information based on the intended route of the passenger (and hence the item of baggage). The data set comprises information such as the identity of the passenger and the flight number. At this point the format of the data set is proprietary, i.e. based upon the airline with which the passenger is flying.

The licence plate (i.e. the unique baggage identifier string) is printed onto a self adhesive baggage tag in bar code format. Additional data (such as the alphanumeric form of the string, the flight number, all or part of the passenger's name and the three letter airport code) are also printed on the tag. Often, the licence plate bar code is printed twice on each face of the tag, with each occurrence of the bar code at 90 degrees to the other.

The tag is then affixed to the baggage item by the operator, usually by looping it though a handle and adhering it to itself.

The first data set is formatted into an industry standard baggage source message (BSM). The BSM contains all of the data necessary to route the bag successfully through the departure airport's baggage handling system, onto the correct aircraft and to the correct position within the destination airport to meet an onward flight (in the event that the journey comprises more than one flight leg). The BSM is sent electronically to each airport, and each relevant baggage handling system in each airport throughout the baggage item's journey. The BSM may also be sent to other airlines.

The BSM contains a number of elements such as the outbound flight information, inbound flight information and passenger details. Not all fields are mandatory and (for example) the inbound flight information is of little or no use routing the bag on the outbound flight.

The licence plate acts as an identifier which can be used to reference the BSM within the relevant airport's computer systems and thereby access this information. The licence plate barcode is scanned at various points on the baggage item's journey such that the BSM can be accessed and the item's route determined. Laser barcode scanning arrays are used to scan the barcodes.

Therefore, correct reading of the barcode and hence correct matching of the baggage item to the BSM is vital to the correct operation of the baggage routing apparatus.

Known tags are susceptible to damage and may be obscured by dirt or parts of the baggage item. If this occurs, and the barcode becomes obscured known barcode scanners cannot successfully determine the licence plate number, and therefore cannot match the baggage item to the BSM.

In this situation, the routing apparatus cannot successfully control gates in the desired manner and so instead the baggage item is diverted to a holding area where it can be manually identified and manually carried to the appropriate place by a handler.

The BSM may not be present in the airport's system. This may occur due to a failure in the BSM transmission, or an error resulting in a failure to generate a BSM at all. This may be because the BSM generating system was deactivated before transmission, or because the BSM receiving system was inactive during transmission. This may occur in particular when considering long haul flights between airports in significantly differing time zones. In these situations, the baggage routing apparatus cannot correctly route a bag to the correct aircraft by controlling gates and instead diverts it to a holding area where it can be manually identified and routed.

A further problem with the known system is that the readers may misread bag tags where certain airlines and carriers may not print bag tags in the format expected by an airport's system.

Various proposals have been made to overcome these problems. RFID tags have been proposed which enable real time tracking of the baggage item and do not require line of sight bar code scanning. Although potentially effective at overcoming barcode reading issues, such systems are very expensive compared to the readable tags described above, and are therefore undesirable. Furthermore, the replacement of barcodes with RFID tags does not overcome the problem of missing BSMs.

It is an aim of the present invention to provide an improved baggage directing apparatus.

According to a first aspect of the invention there is provided a baggage directing apparatus comprising a computer having a memory and a processor, the system being configured to communicate with a baggage router apparatus, the baggage router apparatus being configured to direct baggage from a first location to a second location, wherein the computer is configured to generate by calculation at least a partial baggage source message from an image of a bag tag stored in the memory using the processor and communicate the at least partial baggage source message to the baggage router apparatus for use in directing baggage.

Preferably, the apparatus comprises an image capture apparatus proximate the baggage router apparatus, which image capture apparatus is configured to capture the image of the bag tag. The image capture apparatus may be a digital camera or a line scanner. The image capture apparatus is beneficially passive, i.e. relying on an external light source. According to a second aspect of the invention there is provided a method of routing an item of baggage comprising the steps of: providing a computer having a memory and a processor, using the processor to calculate an at least partial baggage source message from an image of the bag tag stored in the memory, communicating the at least partial baggage source message to a baggage router apparatus to route the item of baggage using the at least partial baggage source message.

According to a third aspect of the invention there is provided a baggage directing apparatus comprising: a computer configured to access a data memory, the data memory having a database comprising a plurality of entries stored therein, each entry comprising a baggage source message and an associated unique baggage identifier corresponding to a bag tag, the computer having an image memory and a processor, wherein the computer is configured to: extract tag data from an artefact of an image of a bag tag stored in the image memory using the processor, which bag tag is unreadable by a barcode scanner, identify a relevant entry in the database corresponding to the bag tag which is unreadable by a barcode scanner using the tag data, look up a baggage source message corresponding to the bag tag which is unreadable by a barcode scanner, and, communicate the baggage source message to the baggage router apparatus to enable the baggage router apparatus to direct the baggage.

According to a forth aspect of the invention there is provided a method of routing an item of baggage comprising the steps of: providing a baggage router apparatus, providing a data memory storing a first data set having a plurality of entries, each entry having a baggage source message and an associated unique baggage identifier corresponding to a bag tag allocated to an item of baggage, providing a computer having a memory and a processor, the computer being configured to access the data memory and to communicate with the router apparatus, providing an image of a bag tag on the memory, using the processor to extract a second data set from an image of the bag tag stored on the image memory using the processor, using the processor to compare the second data set and the first data set to determine a best match entry from the first data set, and, communicating the identity of the baggage source message of the best match entry to the baggage router apparatus to enable the baggage router apparatus to direct the baggage.

According to a fifth aspect of the invention there is provided a computer program comprising a set of instructions which when run on a computer of a baggage directing apparatus converts the system to a system according to the present invention.

An example system according to the invention will now be described with reference to the accompanying figures in which:

Figure 1 is a schematic diagram of a known baggage directing apparatus; Figure 2 is a flow diagram of the operation of the baggage directing apparatus of figure 1; Figure 3 is a diagram of a bag tag,

Figure 4 is a schematic diagram of part of a baggage directing apparatus according to the present invention,

A known baggage handling system 100 is shown in figure 1. The system 100 is located in both a departure airport 102 and a destination airport 104. In this example, the destination airport is an intermediate airport in the journey- i.e. the baggage item experiences a two leg journey. A first aircraft 106 flies from the departure airport 102 to the destination airport 104.

At the departure airport 102, the system 100 comprises a check in computer 108 and a first baggage router apparatus 110. The first baggage router apparatus 110 is shown schematically, but comprises a series of conveyors configured to transport items of baggage from a check in area to the vicinity of the first aircraft 106 for loading thereon. The route of the items of baggage is determined by a series of gates 112 which are controlled by a first sort allocation computer (SAC) 114 to route the items of baggage to the appropriate aircraft 106. The baggage router apparatus 110 comprises a manual handling area 116, the function of which will be described below.

At the destination airport 104, the system 100 comprises a second baggage router apparatus 118. The second baggage router apparatus 118 is shown schematically, but comprises a series of conveyors configured to transport items of baggage from the vicinity of the first aircraft 106 to a second aircraft 120. The route of the items of baggage is determined by a series of gates 122 which are controlled by a second SAC 124 to route the items of baggage to the second aircraft 120. The baggage router apparatus 118 comprises a manual handling area 126, the function of which will be described below.

The check in computer 108 is configured to print a bag tag 128 comprising a printed bar code and selected alphanumeric data relating to a bag 132 as will be described below. The check in computer is also connected to the first SAC 114 and the second SAC 124 via network communication lines 130, which in this case are capable of carrying text packets containing data.

Each gate 112, 122 comprises a junction in the router path controlled by the relevant SAC 114, 124. Each gate 112, 122 comprises a laser barcode scanner (not shown) arranged to scan the bag tag 128 as it enters the gate. The gate 112, 122 is configured to transmit data from the barcode scanner to the SAC 114, 124, which computer can then control the gate to direct a baggage item as appropriate.

Turning to figure 2, the sequence of operation of the system 100 is shown. At step SlOO the bag 132 is checked in at which point the check in computer 108 generates a unique identifier number (licence plate - LP) and a baggage source message (BSM). The unique identifier is a 10 digit numeric string associated with the particular bag 132. The BSM is an industry standard data set comprising passenger and route details. At steps S 102, S 104 the BSM and LP are sent to the destination airport's second SAC 124 and the departure airport's first SAC 114 respectively over the network communication lines 130.

At step S 106 the bag tag 128 is printed. The printed bag tag 128 is shown in figure 3. The bag tag comprises a self adhesive strip 150 onto which is printed a first barcode 152 and a second barcode 154. The barcodes 152, 154 represent the licence plate and are identical and printed at 90 degrees to each other. The licence plate is also printed alphanumerically at 156. Further alphanumerical data is printed on the tag such as the departure airport code 158, passenger name 160 and flight number 162. The tag 128 is printed in an industry standard format or PECTAB (parametric table). The tag printer at the check in computer 108 has firmware which produces the tag 128 in the industry standard PECTAB format. Certain format features will be unique to the airline printing the ticket (within the bounds of the PECTAB format constraints).

The bag tag 128 is affixed to the bag 132, and the bag is sent (by conveyor) to the first router apparatus 110 at step S 108. As the bag approaches the first gate 112, the tag 128 is scanned by the barcode scanner at step SI lO. The barcode scanner reports the LP from the barcode(s) 152, 154 to the first SAC 114. The first SAC 114 looks the LP up in a database of LPs and BSMs to access the relevant BSM at step Sl 12.

The first SAC 114 based on the BSM routing instructions selects the appropriate path for the bag 132 from a number of possible paths that follow the gate 112. Based on this selection, the SAC 114 controls the gate 112 to route the bag 132 onto the appropriate path and on its way towards the first aircraft 106 (step Sl 16).

This process is repeated for the appropriate number of gates required to complete the passage of the bag 132 to the first aircraft 106.

If the barcode scanner cannot read the barcodes 152, 154, then the bag is routed to the handling area 116 where it will be manually identified and routed at step Sl 14. Reasons why the scanner cannot read any of the barcodes include that the barcodes may have become obscured by dirt or the bag tag 128 may have become damaged in transit.

If at step Sl 12 the SAC 114 cannot find a BSM to match the LP then the bag is routed to the handling area 116 where it will be manually identified and routed at step Sl 14. Reasons why the SAC 114 may not find a BSM to match the LP include that the BSM may not have been generated, may not have been delivered to the SAC 114 or may have been the subject of a computer error or malfunction.

Once the first aircraft 106 has arrived at the destination airport 104, the bag 132 is unloaded from the first aircraft 106 and transferred to the second router apparatus 118 at step Sl 18. As the bag approaches the second set of gates 122, the tag 128 is scanned by the barcode scanner at step S 120. The barcode scanner reports the LP from the barcode(s) 152, 154 to the second SAC 124. The second SAC 124 looks the LP up in a database of LPs and BSMs to access the relevant BSM at step S122. Once the BSM is identified, the second SAC 124 can select the desired paths of the bag 132 and control the appropriate gates 122 to route the bag 132 to the second aircraft 120 at step S 124 based on the BSM routing instructions.

In a similar way to the first router apparatus 110, the second router apparatus 118 can eject the bag 132 to a manual handling area 126 at step S 126 if the barcode cannot be read or if the BSM cannot be found.

As such, it is clear that the system 100 is dependent upon successful reading of the barcodes 152, 154. The system is also dependent upon the correct generation, storage and communication of the BSM. If many bags are routed for manual handling then the bags may miss their flight, be manually misdirected or lost.

Figure 4 shows a baggage directing apparatus 200 according to the present invention.

The system 200 comprises a tunnel 202 which is configured to provide an internal shadow free lighting environment. The tunnel 202 is provided with light sealing blinds (not shown) at either end, which the bag 132 can pass through. A conventional conveyor 204 passes through the tunnel and is configured to support the bag 132. A computer 206 is provided and loaded with system control software.

The tunnel 202 is provided with a "magic eye" or movement sensor 208 of known type which detects the presence of the bag 132 and can signal such presence to the computer 206. The tunnel 202 is provided with an LED lighting system 210 which is directed towards the bag 132 to illuminate it and the tag 128 in particular. The LED lighting system, 210 is controlled by the computer 206.

The tunnel 202 comprises a circular array of 8 digital cameras 212. Each camera 212 comprises a hard coded application specific integrated circuit (ASIC) which has the following executables:

• a camera control algorithm which manages the camera's frame capture rate, focus and aperture. The algorithm controls the camera's behaviour locally,

• a barcode reading algorithm which can read full barcodes 152, 154 or parts thereof from an image taken by the camera and translate the data into machine readable format (i.e. all or part of the LP),

• an alphanumeric image processing algorithm which can read alphanumeric data from an image taken by the camera such as the flight number 162 and translate the data into machine readable format,

• a further image artefact processing algorithm which can recognise non- alphanumeric information in images taken by the camera such as colour, tag format, size and position of alphanumeric / barcode data and images e.g. airline logos.

Each ASIC can communicate the results of the above executables to the computer 206. The advantage of the ASIC is that each camera operates locally and independently, negating the need for any heavy networking gear between the computer 206 and cameras 212 for remote control.

The computer 206 is networked to the first sort allocation computer (SAC) 114. The computer 206 is also networked to memories comprising the following databases:

• An LP-BSM database 212 storing each LP against a BSM for each bag 132,

• An LP-BPM (baggage process message) database 214 containing further information about each bag 132,

• A database of carrier tag formats and the general PECTAB format 216,

• A database of LP-PBSMs (pseudo BSMs) 218 as created by the system 200 or equivalent systems (as will be described below),

• External databases 220 (e.g. flight timetables & scedules, real time flight information).

Figure 5 shows the operational sequence of the system 200. As the conveyor 204 conveys the bag 132 into the tunnel 202 the magic eye 208 detects the presence of the bag 132 at step S200 and sends a signal to the computer 206.

At step S202, the computer 206 instructs the cameras 212 to capture an image of the bag, one or more of which images will contain the tag 128. Each camera ASIC will then attempt to detect and read the barcodes 152 / 154 from the image at step S204 using the barcode reading algorithm. If at least one of the barcodes is decipherable then the relevant ASIC will send the LP represented by the barcode to the computer 206 which will then look up and extract the corresponding BSM from the LP-BSM database 212 and send it to the SAC 114 for bag routing.

The ASIC contains an algorithm for reconstructing a single meaningful barcode from at least two partial barcodes (for example if both barcodes 152 and 154 are partially obscured). If the ASIC has been unable to read any complete barcode but was able to read parts of at least two barcodes, the ASIC uses the reconstruction algorithm to attempt to reconstruct the full barcode from the parts. This can be done either by compiling a composite image from the parts of the barcodes deemed readable and then reading the complete barcode from this composite image, or by converting each part separately and compiling a complete LP from the parts. The computer 106 may in addition (or less preferably in place of) the ASIC contain an algorithm for reconstructing a composite LP from parts of LPs. In the preferred embodiment any camera ASIC which is not able to construct a full barcode from the limited parts of barcodes captured still compile a partial LP and sent these to the computer 106. If the computer 106 has not received a full LP from any camera, it will attempt to compile it from any partial LPs received from different cameras 106.

Beneficially where barcodes have been damaged, it is often found that they have been damaged in different areas and therefore the apparatus is able to sometimes compile the full, correct LP when all barcodes are damaged. The compiling algorithms can also be used as a check even if at least one full LP has been received.

If an ASIC cannot read or compile a complete barcode 152 / 154, the ASIC will resort to the alphanumeric image processing algorithm at step S206. The ASIC uses the alphanumeric image processing algorithm to calculate an alphanumeric string and its position on the tag, and send both of these pieces of information to the computer 206. The computer 206 will compare the information to the database of carrier tag formats 216 at step S210 to determine the nature of the alphanumeric string gathered by its position on the tag 128. The computer will also determine the nature of the alphanumeric string by its content (e.g. it may contain two letters followed by a number, indicating a flight number). The position of the string will vary depending on the tag format- for example the computer 206 may determine that the information directly above or below the barcode is the LP.

If the alphanumeric form of the LP can be read at step S212, then the computer 206 extracts the relevant BSM from the LP-BSM database 212 as if the barcode had been read successfully and sends it to the SAC 114 at step S214.

If the alphanumeric form of the LP is not present, or cannot be read, the computer 206 will analyse the text which was retrieved by the cameras 212, and compare it to the PECTAB format in the database of carrier tag formats 216 to determine the nature of each text string at step S216. For example an item of text in a certain location may represent the name of the passenger. This tag data can then be compared to the database of BSMs in the LP-BSM database

212 at step S218 to find a "best match" and the best match BSM sent to the SAC 114 for routing. The tag data is only compared to unmatched BSMs to reduce computing time. The system is configured to only report a BSM to the SAC 114 if a good match is found (i.e. there is a minimum match criterion to be met). If a partial barcode or alphanumeric LP can be extracted, this can also be used to establish the best match

BSM by comparing it to the corresponding LPs as well. For example, from the image the surname of the passenger and the first part of the booking reference may be read and there may only be a single BSM containing these two pieces of data.

If no good match can be found, for example if the tag data is insufficient or if the BSM is not present in the LP-BSM database 212, then the computer 206 uses the available tag data in conjunction with the external databases to generate a pseudo BSM (PBSM). The PBSM may only contain a small amount of the data of the full BSM, however the amount of data can be sufficient to route the bag successfully.

For example, the computer may have the three letter code of the departure airport 158 and the passenger name 160. By referencing the schedule database the computer 206 can extract routing information and create a PBSM which can be communicated to the SAC 114 to route the bag 132.

The computer 206 or ASIC can use alternative artefacts on the tag 128 to extract data from which a PBSM may be created. For example the computer 206 is configured to recognise airline specific tag formats (as described these can vary within the general IATA PECTAB format). The computer 206 is also configured to recognise airline logos. The computer 206 may also be able to detect the green coloured tag edges used for European flights (thus reducing the flight data search field).

Variations in the above described system fall within the scope of the present invention. The complexity of the baggage handling systems at each airport may vary considerably. The above example is appropriate for large airports 102, 104 (such as London Heathrow and New York JFK). Airport 102 may be a small airport in which bags are manually transported from check in to the first aircraft 106. The system may then only be used in the airport 104. Equally, the airport 102 may be complex and require a system according to the invention whereby the airport 104 may be very small and not require automated baggage sorting systems.

The computer software and databases mentioned may be collocated or remotely located. The system is applicable to the destination airport 104 as to the departure airport 102, as it is to any intermediate airport in a multi-leg flight.

The system is retrofittable to existing systems and may serve to act as an optional stage in the bag's journey. For example if the barcode cannot be read by known laser scanners, the bag may be diverted to a system according to the invention.

Preferably, the system may completely replace the laser barcode scanners.

The system may be configured with any kind of tag, even tags without any barcode at all, relying solely on the remaining artefacts.

The array 202 may not be circular, but may be any shape providing a 360 degree field of vision of the bag.