WO2007012352A1

WO2007012352A1 - Apparatus to group together a plurality of physical objects, and method to obtain data from the objects

Info

Publication number: WO2007012352A1
Application number: PCT/EP2006/002413
Authority: WO
Inventors: Rafael Pous Andres
Original assignee: Aida Centre, S.L.
Priority date: 2005-07-26
Filing date: 2006-03-16
Publication date: 2007-02-01
Also published as: ES2273586A1; ES2273586B1

Abstract

The apparatus to group together a plurality of physical objects with a flexible element comprises at least one mobile element (30), associated to at least one feeder (31) of the flexible element (22). The mobile element is mobile in relation to a group of physical objects (20) to wrap said group of physical objects (20) with the flexible element (22). The mobile element (30) comprises at least one antenna (32) associated to a system for interrogating electronic tags by radio frequency, so that during the movement of the mobile element (30) with regard to the group of physical objects (20), the antenna (32) can emit interrogation signals aimed at electronic tags (201) associated to said physical objects (20), and/or receive response signals from said electronic tags (201). The invention also relates to a method to obtain data.

Description

APPARATUS TO GROUP TOGETHER A PLURALITY OF PHYSICAL OBJECTS, AND METHOD TO OBTAIN DATA FROM THE OBJECTS

TECHNICAL FIELD OF THE INVENTION The invention is included in the field of logistics and, more specifically, in the field of transport and storage of products on pallets.

BACKGROUND OF THE INVENTION

In many logistics chains, a plurality of products or elements is grouped together on a base to form what is commonly called a product pallet. Once the products have been grouped together, i.e. once the pallet is full, it is shrink-wrapped with plastic or similar, so that it forms a unit wrapped in said plastic. An automatic shrink-wrapping machine is often used, which may comprise a rotatable platform whereon the pallet is arranged, and an arm which runs from top to bottom and throughout its perimeter whilst the plastic film is being positioned. These types of machines are very well known in the sector and examples thereof are disclosed in, for example, patent application publ. no. EP-A-0022135 and in patent publ. nos. US-A-5140795, US-A- 4993209, US-A-4934123 and US-A-4722170. Once the products stacked on the pallet have been wrapped in the plastic (or by a mesh or similar packaging), it can be said that a composite product has been formed, which is composed of or defined by the stacked products or elements, wrapped in plastic or similar.

On the other hand, radio frequency identification (RFID) technology is known, which is based on electronic tags which may comprise a chip provided with a small antenna. These tags may be incorporated in all the products and enable their remote identification and efficient control throughout the distribution chain, from the manufacturer to the buyer. They further allow the storage of multiple information relating to the article that carries them. This functionality is analogous to that offered by the traditional barcode, with the difference that in RFID tags the information may also be reinserted/modified, in addition to being read without direct line of vision, and that a large number of tags can be read simultaneously, with a single reader. Figure 1 schematically shows an example of a conventional electronic tag in the UHF band, whose essential parts are i) a chip 1 , which may comprise a ROM memory with data identifying the chip and which cannot be modified, a read-write memory -which allows the modification of the information content in the chip-, and a processor, and ii) an antenna 2, e.g. an antenna in dipole form. There are essentially two types of tags in the market: some are passive tags, which only broadcast the information they contain when illuminated by a reader. This type of product is used when the reading distances should not exceed 10 metres. Nevertheless, we can increase the reading distance by making them active. Active tags generally have a small battery which make them broadcast with greater power, and therefore reach a greater distance. Logically, they are more expensive but in turn allow a greater reading range.

Three basic elements are necessary for a RFID-based solution to be totally operative: an electronic tag, a tag reader, which incorporates its own antenna, and an information system. Electronic tags may incorporate a microchip which may store a unique code identifying the product to which they are adhered. The reader sends a series of radio frequency waves to the tag using an antenna, the tag capturing said waves through a small antenna. These interrogation waves activate the microchip which, via the micro antenna, transmit the article's unique code by radio frequency to the reader. In other words, a reader equipment sends an interrogation signal to a set of products and these respond by each one sending their unique identification number. The number of readings per second in an RFID system is of higher orders of magnitude than the traditional barcode-based system. For the above reasons, it can be said that RFID technology is a self-identification technology. Once the reader has received the products' unique codes, it can in turn transmit them to an information system, where the characteristics of the articles in question have previously been stored, e.g. expiry date, material, weight, dimensions, etc. In this way, it is possible to consult the identity of a product and its associated information, at any time, quickly, efficiently and simply throughout the supply chain. The information system can also use this information to control the production, distribution or commercialization processes and improve the management thereof.

Figure 2 schematically reflects the reading process of a plurality of electronic tags 10 of the types described above: step S1 : A reader equipment 11 sends, via an antenna 12, an interrogation signal. This interrogation signal serves as a source of energy or activation for the electronic tags 10, and its frequency represents the clock signal for synchronization. The interrogation signal may optionally include data modulated on a carrier. step S2: Each electronic tag 10 reads the data sent by the reader 11 (if they exist). step S3: The electronic tag 10 responds with its own information. In practice, an anti-collision protocol allows the simultaneous response of multiple electronic tags 10 to be managed. step S4: The information received is interpreted and handled (e.g. stored, etc.) in the reader 11 and/or in one or more electronic systems associated to the reader (e.g. in a goods management system).

RFID technology overcomes many of the limitations of the barcode- based tags. For example:

- Unlike tags with barcodes, electronic tags do not need visual contact with the reader module so that it can read them. The reading can be performed at a distance of up to 10 metres or more.

- Whilst the barcode usually identifies a type of product, electronic tags can identify each individual product.

- RFID technology allows multiple tags to be read simultaneously. Barcodes, in contrast, must be sequentially read.

- Electronic tags can store much more information on a product than tags with a barcode, which usually only contain a code and, in some cases, a price or quantity.

- The content of the electronic tags may be modified as many times as necessary. - RFID technology makes forgery more difficult. A barcode can be reproduced with a simple photocopy. Electronic tags, in contrast, are more difficult to copy.

- Electronic tags may form part of the product or be arranged under a protective surface, for which reason they can be less susceptible to deterioration than barcode tags, which must be visibly positioned.

RFID technology began to be developed several decades ago and has evolved substantially from its beginnings. Initially, a low frequency (LF) band was used, around 125 Khz. (2.4 km wavelength). This band requires relatively large reader antennas to achieve reading distances of less than one metre, although small readers have also been developed with reading distances of a few centimetres. In this band, tag manufacturing is relatively expensive, as it is usually necessary to use coils on ferrite cores, and expensive encapsulations in plastic, glass or ceramic. At present, this band is especially used to identify animals, and is considered a highly consolidated technology, although with a very large dispersion of standards.

Later on, tags were developed in the high frequency (HF) band, around 13.56 MHz (22 m wavelength). These tags are usually cheaper to manufacture than LF tags, although they usually require double layer circuits. The identification is usually limited to reading distances typically less than one metre with antennas of sizes difficult to apply in practice. As with the LF band, communication between tag and reader is produced by magnetic coupling, i.e. by near-field electromagnetic fields, which strongly drop when the distance is increased. Furthermore, the tag reading is especially sensitive to the presence of metal nearby, as it requires continuous retuning of the reader antennas. Additionally, the reading is very sensitive to the tag's orientation with respect to the antenna, which requires three-dimensional antennas if the tag orientation may be variable. For example, with this technology, to detect a person passing through a 1.5-metre wide door, two one square metre antennas may be required, one at each side, and tags of approximately 10 x 20 cm. Unlike LF, in this band there exists a widely- accepted standard communication protocol between the reader and tag, although with diverse variations, which means that great but not total interoperability has been achieved.

More recently a new range of RFID products has been developed in the UHF band of around 900 MHz (33 cm wavelength). This band allows cheaper tags to be manufactured than in the HF band, due to the fact that a double layer is not required nor such high precision in defining the tag antenna. Furthermore, it can operate with reading distances of up to 10 m or more, due to the communication being produced by radiated fields, which are given off from the antennas and travel in the form of electromagnetic waves between tag and reader. With the use of circular polarization, in practice, independence of the tag orientation can be obtained and reader antennas of sizes less than 20 x 20 cm can continue to be used. Furthermore, together with the advance of UHF band technology, the EPC (Electronic Product Code) coding standard was developed, which has been adopted by the UCC/EAN organization, responsible for the barcode standard most commonly used in the trade. Finally, a unique communication protocol between reader and tag, known as Generation 2 (Gen 2), has been proposed and accepted, which ensures interoperability between different equipment and tags. This has lead to the start of the mass use of tagged products thanks to RFID.

In conclusion, it should be stated that RFID technology is widely used today and it is foreseen that, little by little, it will replace the use of tags with barcodes, in many applications, for example and especially, in logistics applications, thanks to its great cost reduction potential. In particular, the use of RFID-based electronic tags is known in logistics applications; for example, the patent application publ. no. WO-A-03/042916 discloses pallets provided with electronic tags which may be read using antennas installed on a forklift truck to transport the pallets.

DESCRIPTION OF THE INVENTION It has been considered that it may be convenient to establish means to enable the identification of data related to products in relation to grouping products, e.g. on a pallet. In this way, a list of data can be established, which univocally identify a composite product consisting, for example, of a pallet that comprises a plurality of products physically grouped together by a plastic ^■ film or similar, with data relating to products which integrate said composite product.

To do this, a first aspect of the invention relates to an apparatus to group together a plurality of physical objects so that they constitute a composite object, wherein the physical objects are retained by a flexible element which wraps, at least partially, said plurality of physical objects. The apparatus has at least one mobile element (e.g. an arm), associated to at least one feeder of the flexible element, the mobile element being configured to be mobile in relation to a group of physical objects to wrap said group of physical objects, at least partially, with said flexible element. In accordance with the invention, the mobile element comprises at least one antenna associated to a system for interrogating electronic tags by radio frequency, so that during the movement of the mobile element with regard to the group of physical objects, said antenna can emit interrogation signals aimed at electronic tags associated to said physical objects, and/or receive response signals from said electronic tags.

Thus, the relative movement between the mobile element and the physical objects is used for two purposes, something that represents a synergic effect:

- on the one hand, the objects are wrapped with the flexible material to physically form the composite object; and

- at the same time, use is made of this relative movement to pass the antenna around the physical objects, something which facilitates the reading of the electronic tags. This reading is not always easy, especially in hostile environments, for which reason a single antenna fixed with regard to the objects perhaps may not manage to capture information from all the tags. The movement of the antenna with regard to the objects causes variations in the distribution of electromagnetic fields between antenna and tags, so that variations arise in the quality of the signals received, and it avoids the blind points in a fixed zone of the pallet, something which increases the possibility of the correct reading of all the tags. The invention thus resolves this problem without requiring new working movements or moments to be performed: it takes advantage of the movement that the mobile element performs for the shrink-wrapping, to also capture data from the shrink-wrapped objects, to thus have available a complete set of data on said objects. A mobile element which "travels across" the entire surface of a group of objects has a high probability of correctly "reading" the tags of all the objects in the group.

The mobile element can, for example, be vertically mobile (e.g. the mobile element can be an arm of a robot or machine which is vertically displaced along the length of a guide or similar).

Additionally, the apparatus may comprise means for supporting a pallet whereon the physical objects are grouped together, and means for rotating a pallet in relation to the mobile element. The means for rotating the pallet may comprise a rotatable platform whereon the pallet can be arranged.

The apparatus may further comprise at least one electronic device associated to the antenna and configured to generate interrogation signals and to record response signals from electronic tags. This electronic device may be in contact with the antenna via a cable or via another communications link.

The electronic device may be configured to store data related to a plurality of electronic tags read in a grouping process of a plurality of physical objects, in a manner associated to an identifier of a corresponding composite object. This composition can have various levels, as objects grouped together in boxes, and boxes grouped together on the pallet.

The electronic device may be provided with means of communication with an external control and/or management system, via any communications system, e.g. via Wireless LAN links or similar. The management of the data related to electronic tags read may take place both in the electronic device associated to the apparatus and in the external system with which the device is connected. In other words, for example, the storage of data related to a plurality of electronic tags read in a grouping process of a plurality of physical objects, associated to an identifier of a corresponding composite object, may take place in the external system.

Another aspect of the invention relates to a method to obtain data relating to a plurality of physical objects during a grouping process of said physical objects, which comprises the steps of: a) arranging said plurality of physical objects so that they form a grouped set of physical objects; b) wrapping, at least partially, said grouped set of physical objects with a flexible element, using at least one mobile element associated to, at least, one feeder of the flexible element, so that a composite object is formed that comprises said plurality of physical objects wrapped, at least partially, in said flexible element.

In accordance with the invention, the method further comprises the step of: c) reading, during step b) and using at least one antenna associated to the mobile element, information stored in electronic tags associated to the physical objects.

During step b), the mobile element can, for example, be vertically displaced and the set of physical objects can be rotated in relation to the mobile element, so that the flexible element wraps, at least laterally, the grouped physical objects and so that data on the electronic tags of said physical objects can be read with the antenna.

The set of physical objects can be rotated by, for example, the use of a rotatable platform whereon the physical objects are arranged.

Step c) can be performed by emitting, with the antenna, interrogation signals and receiving, as a response to the interrogation signals, response signals from the electronic tags. Based on the information read using the antenna, data related to the electronic tags can be extracted and said data can be stored associated to an identifier of a composite object constituted by said physical objects.

DESCRIPTION OF THE DRAWINGS To complement the description and with the object of aiding towards a better understanding of the characteristics of the invention, in accordance with a preferred example of embodiment thereof, a set of drawings is attached as an integral part of said description, wherein the following has been represented, with an illustrative, non-limiting character: Figure 1 Shows a schematic view of an electronic tag, in accordance with the state of the art. Figure 2 Schematically shows an electronic tag reading process, in accordance with the state of the art.

Figure 3 Schematically shows an apparatus in accordance with a preferred embodiment of the invention.

Figure 4 Schematically shows a part of the memory of the electronic device of the apparatus.

PREFERRED EMBODIMENT OF THE INVENTION Figure 3 schematically shows the apparatus in accordance with a possible embodiment of the invention, wherein the apparatus is used to group together a plurality of physical objects 20 so that they constitute a composite object 21 of "pallet" type, wherein the physical objects are retained by a flexible element 22 (schematically illustrated in figure 3), e.g. a plastic sheet, which wraps said plurality of physical objects, at least laterally, so that they are joined together on the pallet. As can be observed in figure 3, the apparatus comprises an arm 30 with a feeder 31 (in this case, positioned at the free end of the arm) of the flexible element 22. The arm can be vertically displaced at the same time as the feeder 31 of the flexible element expulses or releases the flexible element, which may be a plastic tape or similar.

Furthermore, it can be observed how the physical objects 20 are positioned on a pallet 23, which in turn is positioned on a rotatable platform 34. The apparatus has a control and propulsion system (not illustrated) which makes the platform 34 rotate in a synchronized manner with the vertical displacement of the arm 30. In this way, to "wrap" the objects 20 on the pallet 23 with the flexible element 22, a free end of said flexible element is applied to one of the objects 20 or to part of the pallet 23, and then the platform 34 is rotated, at the same time as the arm 30 rises (or lowers, or repetitively rises and lowers, in accordance with the number of layers that one wants to apply), so that the objects are wrapped in the flexible element, from top to bottom. These type of devices are conventional and are known in English as "pallet wrappers" or "stretch wrappers", and in Spanish as pallet "retractiladoras" or "enfardadoras".

Now, in accordance with the invention, at least one antenna 32 associated to a system for interrogating electronic tags by radio frequency is arranged on the arm 30, so that during the movement of the arm 30 with regard to the physical objects 20, this antenna 32 can emit interrogation signals aimed at electronic tags 201 associated to the physical objects 20, and receive response signals from said electronic tags 201. The antenna is in communication by cable (not illustrated) with a RFID reader electronic device 33 which may be integrated in the main body 35 of the apparatus. This electronic device is associated to the antenna or antennas and configured to generate interrogation signals and to record electronic tag response signals. Furthermore, the electronic device 33 is configured to store data related to a plurality of electronic tags 201 read in a grouping process of a plurality of physical objects 20, associated to an identifier of a corresponding composite object 21. Figure 4 schematically illustrates how, in the memory of the electronic device 33, an identifier ID21 of the composite object 21 is associated to a group of identifiers (ID20-1 , ID20-2, ID20-3, ID20-4,...,ID20-n) corresponding to n physical objects that integrate the composite object. Each one of these identifiers may include a substantial quantity of information on the corresponding object.

Now, this storage may also take place in an external system, with which the electronic device 33 may be in contact by communication by cable, by radio frequency or by another means. In this text, the word "comprises" and variations thereof (such as

"comprising", etc.) should not be taken as being exclusive, i.e. they do not exclude the possibility that the item described might include other elements, steps, etc.

Furthermore, the invention is not limited to the particular embodiments described above, but also covers, for example, variations that might be made by the person skilled in the art (for example, as regards the choice of materials, dimensions, components, configuration, etc.), within the bounds of what can be inferred from the claims.

Claims

1. Apparatus to group together a plurality of physical objects (20) so that they constitute a composite object (21 ) wherein the physical objects are retained by a flexible element (22) which wraps, at least partially, said plurality of physical objects, said apparatus comprising at least one mobile element (30), associated to at least one feeder (31) of the flexible element (22), the mobile element (30) being configured to be mobile in relation to a group of physical objects (20) to wrap said group of physical objects (20), at least partially, with said flexible element (22); characterized in that said mobile element (30) comprises at least one antenna (32) associated to a system for interrogating electronic tags by radio frequency, so that during the movement of the mobile element (30) in relation to the group of physical objects (20), said antenna (32) can emit interrogation signals aimed at electronic tags (201 ) associated to said physical objects (20), and/or receive response signals from said electronic tags (201 ).

2. Apparatus according to claim 1 , characterized in that the mobile element (30) is vertically mobile.

3. Apparatus according to claim 2, characterized in that it further comprises means for supporting the pallet (23) whereon the physical objects (20) are grouped together, and means for rotating the pallet (23) in relation to the mobile element. (30).

4. Apparatus according to claim 3, characterized in that the means for rotating the pallet (23) comprise a rotatable platform (34) whereon the pallet can be arranged.

5. Apparatus according to any of the previous claims, characterized in that it further comprises at least one electronic device (33) associated to the antenna and configured to generate interrogation signals and to record response signals from electronic tags (201).

6. Apparatus according to any of the previous claims, characterized in that the electronic device (33) is configured to store data relating to a plurality of electronic tags read in a grouping process of a plurality of physical objects (20), in a manner associated to an identifier of a corresponding composite object (21 ).

7. Method to obtain data relating to a plurality of physical objects during a grouping process of said physical objects, which comprises the steps of: a) arranging said plurality of physical objects (20) so that they form a grouped set of physical objects; b) wrapping, at least partially, said grouped set of physical objects with a flexible element (22), using at least one mobile element (30) associated to at least one feeder (31 ) of the flexible element (22), so that a composite object (21 ) is formed that comprises said plurality of physical objects (20) wrapped, at least partially, in said flexible element (22); characterized in that it further comprises the step of c) reading, during step b) and using at least one antenna (32) associated to the mobile element (30), information stored in electronic tags (201 ) associated to the physical objects (20).

8. Method according to claim 7, characterized in that during step b), the mobile element (30) is vertically displaced and the set of the physical objects (20) is rotated in relation to the mobile element, so that the flexible element (22) wraps, at least laterally, the grouped physical objects (20) and so that data from the electronic tags (201) of said physical objects can be read with the antenna (32).

9. Method according to claim 8, characterized in that the set of physical objects (20) rotates by the use of a rotatable platform whereon the physical objects are arranged.

10. Method according to any of claims 7-9, characterized in that step c) is performed by emitting, with the antenna (32), interrogation signals and receiving, as a response to the interrogation signals, response signals from the electronic tags (201 ).

11. Method according to any of claims 7-10, characterized in that, based on the information read using the antenna (32), data is extracted related to the electronic tags (201) and said data is stored associated to an identifier of a composite object (21) comprised by physical objects (20) is stored.