SYSTEM FOR RECYCLING WASTE

Technical field

The present disclosure relates to a disposable waste bag, a system and a method of gripping and emptying such disposable waste bag.

Background

It is known and generally desirable, to sort waste into different fractions for recycling. Economic and environmental handling of the waste requires some types of waste to be packed and thereafter transported to a sorting plant for further sorting and/or processing, e.g. recycling. An environmental way is to sort the waste at waste sources and to pack waste into different categories, such as recyclable plastic, metal, glass, etc.

Disposable waste bags are widely used for containing and transporting waste. Such a waste bag is normally made of thin, flexible, plastic film, nonwoven fabric, or plastic textile, e.g. by blow moulding. Alternatively, the waste bags may be heat sealed together or bonded by adhesions, welding or stitching.

The waste bags filled with wastes are transported to the sorting plant for sorting. Systems and methods for sorting of waste are known from, e.g. WO2004/050264A1 . Waste bags with identifications, such as different colours, can be used for sorting the waste bags containing different sorts of waste.

However, in areas with limited access of waste carrier vehicles, bins, such as villages accessible only by stair paths and the places in a center of a pedestrian area, the waste bags are normally collected in a larger bag. The larger bag is carried to waste carrier vehicles by a person and then

transported to the sorting plant. Thus, the waste bags contained inside the larger bag need to be removed from the larger bag to be able to be sorted. US5002451 A discloses a waste material debagging apparatus for emptying waste bags. However, a drawback of such debagging apparatus is that when the larger bag is debagged by a destructive debagging process, e.g., by a penetrating means, the waste bags contained in the larger bag are normally broken such that the waste already sorted at waste sources will be mixed up again. Thus, the different categories of waste have to be sorted once again in the sorting plant. Furthermore, due to the scattered waste, the debagging devices and the sorting plant have to be cleaned more frequently.

The debagging process can be manually handled to secure the integrity of the contained waste bags. However, such a manual process is tedious and inefficient.

While waste bags, systems and methods of debagging waste bags mentioned above have found extensive use, there is a desire to provide a disposable waste bag which facilitates the debagging and thus improves the debagging efficiency.

Therefore, there remains a need for an improved disposable waste bag.

Summary

An object of the present disclosure is to provide an improved disposable waste bag.

A particular object is to provide a disposable waste bag which is improved in terms of facilitating the debagging and improving the debagging efficiency.

The invention is defined by the appended independent claims, with embodiments being set forth in the appended dependent claims in the following description and in the attached drawings.

According to a first aspect, there is provided a disposable waste bag, comprising an open end, a closed end, spaced from the open end, as seen in a longitudinal direction of the bag, a wall, extending between the closed end and the open end, an optically readable element arranged on a wall of a first portion of the bag, which optically readable element represents information of a relative position of at least a second portion of the bag, and a gripping portion, extending from the closed end in a direction opposite the open end, wherein said second portion of the bag is a portion of the gripping portion and/or a portion of a corner indention.

An "optically readable element" is defined as one or more patterns that is/are specifically adapted for machine reading.

A waste bag as defined makes it possible to efficiently and reliably automate emptying of the bag.

The optically readable element may comprise at least one point representing information of a relative position of the at least a second portion of the bag.

The point may be identified as an intersection between at least two lines, which meet at an angle of 15 ^° -165 ^° , 30 ^° -150 ^° , preferably 45 ^° -135 ^° or 80 ^° -100 ^° .

Lines may be created by line elements, or by edges of geometric shapes, such as rectangles, triangles, etc. That is, the lines may be merely lines formed of a line with different color than its background. Alternatively, the lines may be formed by the edge of the geometric shape having a different color than the background.

The point may comprise a unique identifier associated to it such that the point is uniquely identifiable.

The optically readable element may comprise a plurality of said uniquely identifiable points, disposed over an area of the optically readable element.

The optically readable element may be arranged within a portion of the bag that is situated within a distance of less than 50 % of a length of the bag, from the closed end.

The optically readable element may extend over at least 10%, preferably at least 20 %, 30 %, 40 % or 50 %, of the length of the bag, in the longitudinal direction of the bag.

The optically readable element may extend over at least 50 %, preferably at least 60 % or 70 %, of a circumference of the bag along a circumferential direction of the bag.

The information may be represented by a sub area of the optically readable element which is at most 50 %, preferably at most 40 %, more preferably at most 30 %, 20 % or 10 % of the area of the optically readable element.

The optically readable element may comprise a pattern, color or colors, or a symbol.

For example, the optically readable element may comprise a one or more patterns and/or symbols. Such patterns and/or symbols may be monochrome or they may comprise two or more colors.

The pattern may comprise a geometrical pattern. The optically readable element may comprise a character or a number. The optically readable element may comprise a plurality of stripes. At least two stripes may have different widths.

The disposable waste bag may further comprise a corner indention, provided at the closed end and defined at least by the closed end and a longitudinal side of the bag, said corner indention being adapted to counteract contents reaching corners of the bag at the closed end.

The corner indention may be defined also by a joint extending along a direction forming an angle of 10 ^° -80 ^° to the longitudinal side of the bag.

The corner indention may extend at least 2 %, preferably at least 5 %, more preferably at least 10 % or at least 15 %, of the length of the bag, in the longitudinal direction of the bag.

The corner indention may extend at least 10%, preferably at least 20%, more preferably at least 30 % or 40 %, of a width of the bag when the bag is in a collapsed state, in a transverse direction of the bag.

The angle presented by the extended joint and the closed end may be at most 60°, preferably at most 45° or 30°.

The extended joint may comprise at least one non-linear portion.

That is, the line may be a curve or otherwise bent portion.

The corner indention may be formed by a gusset crease.

The corner indention may be formed by a weld, stitching or an adhesive. In particular, the corner indention may be formed by a so-called "star weld". Alternatively, the closed end may be formed by a constriction of a portion of the bag. In this case the bag may be formed by a tubular member, which is constricted to form the closed end.

The constriction may be maintained by at least one of a knot, a cord, a cable tie or a clamp. A width of the gripping portion in the longitudinal direction may be at least 5 mm, preferably at least 7 mm or 10 mm.

The width of the gripping portion in the longitudinal direction is at most 100 mm, preferably at most 50 mm, 40 mm or 20 mm.

The gripping portion may be outside the interior of the bag.

The gripping portion may be formed by a weld, stitching or adhesive.

That is, the gripping portion may be formed by means of one or more welds separating the interior of the waste bag from the gripping portion.

The gripping portion may comprise a reinforcing element.

The corner indention may comprise a reinforcing element.

The reinforcing element may be attached by welding, stitching or adhesion.

The reinforcing element may comprise a reinforcing strip.

The reinforcing element may be formed of a material selected from but not limited to: metal, wood, polymer, paper, woven fibre web and non-woven fibre web.

The closed end may comprise a weld across the bag along the transverse direction of the bag.

The bag may be formed of a flexible material, such as a polymer material or paper. The material may be a thin sheet or film, provided as one or more sheets which are joined together, or as a tube, which is processed by welding the portions that are to form gripping and corner portions.

Preferably, the bag is formed of paper, polymer film, woven fibre web or non-woven fibre web. As one option, a coated paper may be used.

A volume of the bag may be at least 5 litres, preferably at least 10 litres, more preferably at least 20 litres, 30 litres, 40 litres or 50 litres.

The volume of the bag may be at most 350 litres, preferably at most 300 litres, more preferably at most 250 litres, 200 litres, 150 litres or 100 litres. According to a second aspect, there is provided a bag gripping system, comprising an optical device, for capturing 3D data of the bag and for capturing an image of at least a first portion of the bag, said image depicting an optically readable element, which is arranged on a wall of the bag and which represents information of a relative position of at least a second portion of the bag, the second portion being a portion of a gripping portion extending from the closed end in a direction opposite an open end of the bag, and/or a portion of a corner indention, a control device, comprising a processor arranged to perform the following steps using the captured 3D data and the captured image to determine a spatial position and orientation of the second portion of the bag, controlling a gripping device to engage the second portion of the bag, such that the bag is held by the gripping device to an extent sufficient to allow the gripping device to lift or move the bag.

3D data may typically be data describing the bag's position and orientation. Such 3D data may be generated by e.g. laser scanning and/or by means of a stereoscopic camera.

The optical device may comprise a laser scanning device, e.g. a line laser.

The optical device may further comprise one or a plurality of cameras. The captured 3D data may comprise stereo images.

The system may further comprise a conveyor for moving the bag after the gripping device engaging the second portion of the bag.

The gripping device may comprise a grip enhanced engagement surface for providing enhanced friction relative to the bag.

Alternatively, or in addition, the gripping device may comprise at least one protrusion for enhancing engagement with the bag by piercing or plastically deforming it.

According to a third aspect, there is provided a bag emptying system, comprising an optical device, for capturing 3D data of the bag and for capturing an image of at least a first portion of the bag, said image depicting an optically readable element, which is arranged on a wall of the bag and which represents information of a relative position of at least a second portion of the bag, the second portion being a portion of a gripping portion and/or a portion of a corner indention, a control device, comprising a processor configured to perform the following steps. Using the captured 3D data and the captured image including the optically readable element to determine a spatial position and orientation of the second portion of the bag, controlling a gripping device to engage the second portion of the bag, controlling the gripping device to move the second portion relative to a content of the bag such that the content is evacuated from the bag.

The system may further comprise a conveyor for moving the bag after the gripping device engaging the second portion of the bag.

The control device may be further configured for performing controlling the gripping device to lift the second portion upwardly.

The gripping device may comprise a grip enhanced engagement surface for providing enhanced friction relative to the bag.

Alternatively, or in addition, the gripping device may comprise at least one protrusion for enhancing engagement with the bag by piercing or plastically deforming it.

According to a fourth aspect, there is provided a system for recycling waste, comprising a plurality of bags described above, and a bag gripping system or a bag emptying system as described above. The optical device is configured to capture an image of the optically readable element, the optical device is configured to capture 3D data of the one of said bags when the bag is filled with contents to at least 10 % of its volume, preferably at least 25 % or at least 50 %, and the processor is configured: to identify a position and orientation of the second portion of the bag, and to control the gripping device to engage the second portion of the bag.

The processor may be configured to control the gripping device so as to raise the second portion of the bag to an extent sufficient to cause evacuation of the contents from the bag.

The system may further comprise a conveyor for transporting the bag on a conveyor, wherein the optical device is configured to capture the image and the 3D data while the bag carried on the conveyor.

The capture may be performed while the conveyor is moving or when the conveyor is temporarily stopped. The system may further comprise a conveyor for transporting the bag on a conveyor, wherein the processor is configured to control the gripping device to engage the second portion of the bag while the bag is carried on the conveyor.

The engagement may be performed while the conveyor is moving or when the conveyor is temporarily stopped.

According to a fifth aspect, there is provided a method of gripping a bag, comprising providing a disposable waste bag as described above, the bag being filled with contents to at least 10 % of its volume, preferably at least 25 % or at least 50 %, arranging the bag on a carrier, capturing an image of at least a first portion of the bag, said image depicting an optically readable element, which is arranged on a wall of the bag and which represents information of a relative position of at least a second portion of the bag, capturing 3D data of the bag, using the image including the optically readable element and the 3D data to determine a spatial position and orientation of the second portion of the bag, and controlling a gripping device to engage the second portion of the bag.

Capturing 3D data may comprise laser scanning, e.g. by a line laser. Capturing the image may comprise scanning, e.g. by one or a plurality of cameras.

The captured 3D data may comprise stereo images.

The method may further comprise moving the bag by means of a conveyor after the gripping device engaging the second portion.

The gripping device may be controlled to lift the second portion upwardly.

The contents may comprise a plurality of individual bags, in particular waste bags, having a smaller volume than the bag, and the bags may be evacuated from the bag and transported to a sorting station, where the bags are sorted into at least two fractions depending on a parameter that is derivable from said bags.

The method may further comprise piercing or plastically deforming the bag upon gripping it with the gripping device. That is, the piercing or deforming occurs at the part of the bag which is engaged by the gripping device, and typically within the footprint of an engagement surface of the gripping device.

According to a sixth aspect, there is provided a method of emptying a bag, comprising providing a disposable waste bag as described above, the bag being filled with contents to at least 10 % of its volume, preferably at least 25 % or at least 50 %, arranging the bag on the carrier, capturing an image of at least a first portion of the bag, said image depicting an optically readable element, which is arranged on a wall of the bag and which represents information of a relative position of at least a second portion of the bag, capturing 3D data of the bag, using the image and the 3D data to determine a spatial position and orientation of the second portion of the bag, controlling a gripping device to engage the second portion, and moving the second portion relative to the contents such that the contents are evacuated from the bag.

The method may further comprise moving the bag by means of a conveyor after the gripping device engaging the second portion.

The gripping device may be controlled to lift the second portion upwardly.

The contents may comprise a plurality of individual waste bags, in particular waste bags, having a smaller volume than the bag, and the bags may be evacuated from the bag and transported to a sorting station, where the bags are sorted into at least two fractions depending on a parameter that is derivable from said bags.

The method may further comprise piercing or plastically deforming the bag upon gripping it with the gripping device. That is, the piercing or deforming occurs at the part of the bag which is engaged by the gripping device, and typically within the footprint of an engagement surface of the gripping device.

Brief description of the drawings

Fig. 1 schematically illustrates a disposable waste bag in a collapsed state.

Fig. 2 schematically illustrates an example of the bag of Fig. 1 .

Fig. 3 schematically illustrates another example of the bag of Fig. 1. Figs 4a-4b schematically illustrates a device for emptying waste bags. Fig. 5 schematically illustrates another embodiment of a disposable waste bag.

Figs 6a-6b schematically illustrate a gripping device 204.

Detailed description

Fig. 1 schematically illustrates a disposable waste bag 100 in a collapsed state. The disposable waste bag comprises an open end 2, a closed end 1 , spaced from the open end 2, in a longitudinal direction of the bag 100. The bag further comprises a gripping portion 4, extending from the closed end 1 in a direction opposite the open end 2 and a corner indention. The corner indention 5 is provided at the closed end 1 and defined by the closed end 1 , a longitudinal side of the bag and a weld 6 extending at an angle relative to the closed end 1 . The angle of the weld 6 relative to the closed end is between 10° and 80°. The angle may be at most 60°, preferably at most 45° or 30°.

An optically readable element 3 is arranged on the wall of the bag between the closed end 1 and the open end 2. The optically readable element 3 represents information of a relative position of at least a portion of the bag. The information may comprise, e.g., an orientation of the portion, a distance from the pattern to the portion.

The optically readable element 3 may present information of a relative position of a portion of the gripping portion and/or a portion of the corner indention. For example, the information may be the orientation of the gripping portion 1 , the corner indention 5, the weld 6 and the closed end 1 . The information may also be a distance from the element to the gripping portion 1 , the corner indention 5, the weld 6 and the closed end 1.

Figs 1 -3 illustrate three disposable waste bags with different optically readable elements 3. The optically readable element may comprise individual sub elements 7, as shown in Figs 1 -2. The sub elements 7 may be aligned, as in Figs 1 -2 or stochastic arranged in the area. At least one sub element 7 may present information of a relative position of the portion. Alternatively, the optically readable element may comprise a plurality of stripes, as in Fig. 3. At least two stripes may have different widths.

The optically readable element may comprise a geometrical pattern, as shown in Fig.2. The optically readable element may comprise a character, as shown in Fig.1. Alternatively, the optically readable element may comprise a number.

The optically readable element comprise at least one point 8 identified as an intersection between at least two lines, as shown in Figs 1 -2. The point 8 may represent information of a relative position of at least a second portion of the bag. The second portion may be a portion of the gripping portion and/or a portion of the corner indention.

The optically readable element may comprise a plurality of such points 8, disposed over an area of the optically readable element 3, as in Figs 1 -2.

The optically readable element may be arranged closed to the closed end 1 , as shown in Figs 1 -3. A distance from the closed end to the optically readable element may be less than 50 % of a length of the bag.

The optically readable element may extend in the longitudinal direction, over at least 10%, of the length of the bag.

The disposable waste bags in Figs 1 -3 are in a collapsed state showing a front side provided with the optically readable element. The back side of the bag (not shown) may be provided with an optically readable element. The optically readable element may be extended over at least 50 %, preferably at least 60 % or 70 %, of a circumference of the bag along a circumferential direction of the bag.

By extending the optically readable element in the longitudinal direction and/or the circumferential direction of the bag, the likelihood that at least a sufficient part of the optically readable element is visible, when the bag is filled with waste, and transported on a conveyor, in which case the bag may be standing up, or lying on its side.

As illustrated in Figs 1 -3, the bag may comprise two corner indentions

5 each situated on one end of the closed end 1 , when the bag is in the collapsed state. The corner indention 5 may extend at least 10 %, preferably at least 20 %, more preferably at least 30 %, of the length of the bag, in the longitudinal direction of the bag.

The corner indention may be formed by welding together the layers of film forming opposite sides of the bag. Hence, the corner indentions are, like the gripping portion, not filled with waste, and thus will remain thin, though double walled, portions of the bag.

The corner indention may extend at least 10%, preferably at least 20%, more preferably at least 30 % or 40 %, of a width of the bag when the bag is in the collapsed state, in a transverse direction of the bag.

As in Figs 1 -3, the corner indention may extend a same distance in both the longitudinal and transverse directions of the bag. Alternatively, the corner indention may extend differently in the longitudinal and transverse directions.

In Figs 1 -3, the weld may be linear. As one option, the weld may comprise at least one non-linear portion. As another option, the weld may be curved.

The width w1 of the gripping portion may be long enough for gripping. The width may be at least 5 mm, preferably at least 7 mm or 10 mm.

The width w1 of the gripping portion may be at most 50 mm, preferably at most 40 mm or 20 mm.

In Figs 1 -3, the gripping portion 4 and the corner indentions 5 are separate portions. Alternatively, the gripping portion 4 and the corner indentions 5 may be formed into one portion, e.g., by welding.

Fig. 4a schematically illustrates a waste bag emptying system, comprising a conveyor 205 for transporting a plurality of waste bags 100, a support frame 201 and a robot 203.

A pair of cameras 202a, 202b may be arranged on the support frame. Further camera(s) may be arranged e.g. on the robot 203, such as on or close to the gripping device. In particular a line laser scanner may be arranged either on the support frame 201 or on the robot 203, or on both.

The robot 203 is illustrated as being arranged on a floor beside the conveyor 205, but may alternatively be arranged on the support frame 201 . The robot 203 may be a general industrial type robot with 5 or 6 axes, fitted with a gripping device 204 that is suitable for engaging the gripping portion 4 of the waste bag 100. For example, jaws of the gripping device 204 may provide a 2D contact surface, between which the gripping portion 4 is received. Optionally, one or more protrusions or even pins may be provided to deform or pierce the gripping portion for enhanced grip.

A controller 300 may be provided for controlling the robot and the conveyor 205. To this end, the controller 300 may receive input data from the camera(s) 202a, 202b.

As illustrated in Fig. 4a and 4b, waste bags 100 are transported on the conveyor 205. As a preceding step, the waste bags 100 may be prearranged on the conveyor 205, e.g. with their longitudinal direction along the

transportation direction, as illustrated. Moreover, the waste bags 100 may be separated from each other along the transportation direction, the separation being sufficient to allow for the identification, gripping and emptying of the waste bags.

As a waste bag 100 reaches the emptying station, the conveyor 205 may, but need not, slow down or stop. Images of the waste bag 100 are captured by the cameras 202a, 202b, and any laser device (not shown).

Optically readable elements are identified and a spatial position and orientation of the gripping portion is determined.

The robot 203 with the gripping device 204 is then directed to engage the gripping portion 4. Once engaged, the robot 203 may typically lift the gripping portion 4 upwardly. During the lifting, the conveyor 205 may, but need not, move in the transportation direction.

Methods of determining the geometry of 3D objects and controlling a robot to engage such objects are known from e.g. WO2007046763A1 .

Once the gripping portion 4 has reached a predetermined vertical level, such that the contents of the waste bag 100 can be assumed to have been evacuated, the robot 203 may optionally shake or otherwise agitate the supposedly empty waste bag 100.

The robot 203 may then dispose of the empty waste bag, e.g. in a container (not shown) near the emptying station. The contents of the waste bag may continue to be transported on the conveyor for further processing, such as sorting.

Fig. 5 schematically illustrates a disposable waste bag having gusset creases 61 extending longitudinally and thus effectively forming, together with the closed end (e.g. a weld) corner indentions 51 , which counteract material lingering at the corner portions of the closed end of the bag.

Figs 6a-6b schematically illustrate a gripping device 204, which may be used to grip a gripping portion of the waste bag discussed above.

The gripping device 204 may be attached to an arm 2041 of the robot 203 via a joint 2042, which may allow the gripping device 204 to move with one or more degrees of freedom.

The gripping device may comprise a pair of jaws 2043a, 2043b, which may have a respective bag engaging portion 2044a, 2044b. The bag engaging portions 2044a, 2044b may be controllably movable towards, and away from, each other, for example through rotation about one or more joints 2042.

The bag engaging portions 2044a, 2044b may comprise engagement surfaces 2045a, 2045b, which may be provided with grip enhancing means, such as a material having greater coefficient of friction than the material of the jaws 2043a, 2043b. Such grip material may be provided as a continuous layer on the engagement surfaces 2045a, 2045b, or as one or more dots, ridges or other patterns on one, or both, of the engagement surfaces 2045a, 2045b.

In addition, and referring to Fig. 6b, the engagement surfaces 2045a, 2045b may comprise a protrusion 2046, arranged on one of the engagement surfaces 2045b and a corresponding recess 2047 provided on the other one of the engagement surfaces 2045a, whereby the protrusion (or protrusions) may enter the corresponding recess (or recesses) when the engagement surfaces 2045a, 2045b engage a gripping portion of the bag.

The protrusion 2046 may be designed to pierce the gripping portion of the bag, or merely to cause plastic deformation thereof, such that a positively interlocking engagement with the bag is achieved.