Method and system for feeding a flatwork item to a transport conveyor and / or a flatwork treating device

Abstract

The invention relates to a system and method for feeding a flatwork item to a transport conveyor and / or a flatwork treating device. The method comprises thereto the steps of providing at least one flatwork item, determining a position and / or orientation of a first corner of the at least one flatwork item based on an imaging process and gripping the determined first corner of the at least one flatwork item. The positioned and / or orientation of the second corner of the flatwork item is also determined based on an imaging process, and when both corners are gripped the at least one flatwork item is fed to a transport conveyor and / or a flatwork treating device.

Description

[0001] Method and system for feeding a flatwork item to a transport conveyor and / or a flatwork treating device

[0002] The invention relates to a method for feeding a flatwork item to a transport conveyor and / or a flatwork treating device. The invention also relates to a system for feeding a flatwork item to a transport conveyor and / or a flatwork treating device. The invention further relates to the use of such system.

[0003] Industrial laundry services are specialized in providing a full service laundry solution for, for example, hotels, restaurant, gyms, spas, schools, care and nursing homes or any further. This means that the dirty washing of such party is provided to the industrial laundry service and will be returned once clean. Therefore, batches of used or soiled laundry need to be sorted, washed, dried, optionally ironed or pressed and subsequently folded such that they can be returned to their place of use. The washing and drying process is almost fully automated by making use of a sequence of washing machines, dryers and / or presses and automated transport systems. Also folding of laundry can be automated by making use of a folding device. However, for some steps the laundry item needs to be provided to the following processing unit in a rather specific arrangement. For example the sorting of a bunch of laundry is done manually. Another example is feeding of laundry to a feed conveyor or a mangle, or the insertion of textile in a folding machine. For the latter, it is of importance that for example a sheet (or towel) is positioned such that a first side of the typically rectangular or square sheet is perpendicular to a transport direction and that two corners of the sheet are parallel to each other when inserted in two vertically positioned rollers or on a conveyor. This specific alignment is a typical requirement of conventional folding devices and further machinery used in this technical field. Since this specific orientation of sheets it is difficult to automate this step and manual labor is nowadays still applied on a large scale. The applicant has found a solution which enables further automating of the entire system.

[0004] A method and system for feeding a flatwork item to a transport conveyor and / or a flatwork treating device is described in W02021 / 034190 of the applicant. However, it was experimentally found that this system and method experience a few limitations and difficulties. The quality of the output, thus the way wherein flatwork items are fed to a transport conveyor and / or a flatwork treating device cannot always be guaranteed with the known systems and the system and method experience difficulties in further increasing the output thereof.

[0005] It is therefore a goal of the invention to provide a method and / or a system which can contribute to further automating of an industrial laundry process. Alternatively, a goal of the invention to provide an improved system and method for feeding a flatwork item to a transport conveyor or a flatwork treating device.

[0006] The invention provides thereto a method for feeding a flatwork item, such as a towel, cloth, bed sheet, napkin, bed linen, duvet, tabletop and / or pillowcase, to a transport conveyor and / or a flatwork treating device, comprising the steps of:

[0007] - providing at least one flatwork item;

[0008] - optionally capturing at least one image of at least part of the at least one flatwork item, in particular of at least one first corner of the at least one flatwork item;

[0009] - optionally determining a possible position and / or orientation of a first corner of the at least one flatwork item in particular by means of at least one processor;

[0010] - gripping a first corner, in particular the determined first corner, of the at least one flatwork item by at least one initial gripper in particular such that at least one further corner and preferably each further corner of the at least one flatwork item substantially hangs free;

[0011] - retaining at least part of the at least one flatwork item at a distance from the first corner by at least one clamp and preferably lifting at least part of the at least one flatwork item such that at least one second corner of the at least one flatwork item which is adjacent to the first corner substantially hangs free;

[0012] - displacing the at least one flatwork item onto at least one carrying surface and releasing the at least one flatwork from the at least one initial gripper and / or the at least one clamp in particular such that at least the first corner and the second corner of the at least one flatwork item are positioned upon the at least one carrying surface; - capturing at least one image of at least part of the first corner and at least one image of at least part the second corner of the at least one flatwork item;

[0013] - determining a possible position and / or orientation of the first corner of the at least one flatwork item and a possible position and / or orientation of the second corner of the flatwork item by means of at least one processor;

[0014] - gripping the determined first corner of the at least one flatwork item by at least one first gripper and gripping the determined second corner of the at least one flatwork item by at least one second gripper; and

[0015] - optionally feeding the at least one flatwork item to a transport conveyor and / or a flatwork treating device via the at least one first gripper and / or the at least one second gripper.

[0016] The method according to the present invention provides an improved, an in particular more reliable method to enable gripping of a first corner and a second corner of a flatwork item in an automated manner. Correct gripping of the first and second corner and keeping the flatwork item in a straight and unfolded or twisted configuration is important to ensure the quality of the output. The flatwork items need to be fed to the transport conveyor and / or flatwork treating device in a predetermined and consistent manner. In case the flatwork item is not optimally provided to the next treating device the quality of the next processing step there can be negatively affected. The most challenging part in practice is to detect and grip a first corner of the flatwork item. In the method according to the present invention, however, the gripped first corner of the flatwork item is let loose by the initial gripper and subsequently determined again by an imaging device and gripped again by a first gripper. Since the detection step for detecting the second corner is performed whilst the flatwork item is positioned upon a carrying surface and at least the first corner and second corner of the flatwork item are left free, the position and orientation of the first and second corner can be determined very accurately. It is also relatively easy to predict where the corners are located, and thus where the images are to be captured. This results in that the respective first and second grippers can always grip the respective first and second corner of the flatwork item in the same orientation such that a consistent and repeatable output can be obtained. It is counter intuitive to let go of the first corner of the flatwork item once it is gripped. As indicated above, it is a challenge to determine and grip the first corner, and once this first corner is gripped, the flatwork item is subjected to several processing steps to get the second corner and / or to get the flatwork item in the desired configuration which results in that the first corner is typically strictly retained during all further processing steps. In the prior art, it is possible that multiple grippers are cooperating in the retention of the first corner, for example that the gripping action is transferred to another gripper, but it is not seen that a determined and first corner is completely discarded from gripping.

[0017] The method steps of the method according to the invention can be performed in a repetitive way ensuring a high output quality and thus a very low failure rate. This also enables that the production capacity of the method and in particular of the corresponding system according to the invention can be increased significantly.

[0018] The at least one clamp which retains at least part of the at least one flatwork item at a distance from the first corner by at least one clamp and which may lift at least part of the at least one flatwork item such that at least one second corner of the at least one flatwork item which is adjacent to the first corner substantially hangs free, typically retains the at least one flatwork item at a part of the towel which is at a distance from the first corner and the first edge of the at least one flatwork item. The second corner is thereby typically adjacent to the first corner. The first corner and the second corner are typically connected via a first edge. Within the context of the present invention, the first corner of the flatwork item is the corner which is determined first. The second corner is the corner which is adjacent to said first corner, typically seen from a leading edge of the flatwork item. The leading edge can for example be the edge which is fed first to the transport conveyor or a flatwork treating device. Preferably, the first corner is determined by analysis of at least one image of at least part of at least one corner, in particular at least one first corner, of the at least one flatwork item which at least one image is captured by an imaging device. Once the position and / or orientation of the first corner is determined, said first corner can be gripped by at least one initial gripper. The first gripper preferably retains the flatwork item in a hanging configuration, in particular such that at least one further corner and preferably each further corner of the at least one flatwork item substantially hangs free. The free configuration of the flatwork item is beneficial as the further corners will typically be relatively easy detectable and the flatwork item can be prepared for positioning upon the carrying surface. In the method according to the invention, a clamp will retain at least part of the at least one flatwork item at a distance from the first corner and preferably lift at least part of the at least one flatwork item such that the second corner substantially hangs free. Now the flatwork item is in a useful orientation to be put upon a carrying surface in a predetermined manner. Thereto, at least one initial gripper and / or at least clamp displace the at least one flatwork item upon or onto at least one carrying surface. The at least one flatwork is subsequently from the at least one initial gripper and preferably also from the at least one clamp in particular such that at least the first corner and the second corner of the at least one flatwork item are positioned upon the at least one carrying surface. The flatwork item is preferably at least partially dragged over the carrying surface in particular such that a substantially straight first edge, between the first and second corner, is of the flatwork item is obtained. Releasing of the flatwork item from the initial gripper typically results in a drop of at least the first corner of the flatwork item. For the further handling of the flatwork item, the first corner and second corner are captured in at least one image. It is possible that at least one image of at least part of the first corner is made and that at least one image of at least part the second corner is made. It is also possible that an image is made which captures at least part of the first corner and at least part of the second corner. Subsequently, the possible position and / or orientation of the first corner of the at least one flatwork item and the possible position and / or orientation of the second corner of the flatwork item are determined, in particular by means of at least one processor. The processor thereto make use of at least one image or multiple images are captured in the previous step. Once the position and / or orientation of the first corner and second corner are determined, said determined first corner can be gripped by at least one first gripper and said determined second corner can be gripped by at least one second gripper. The flatwork item is now retained via its first and second corners by respective first and second grippers and can be fed to a further processing device.

[0019] The use of captured imagines of the first and second corner to determine the (exact) position and / or orientation corners of the flatwork item results in that the grippers and / or clamps can be controlled precisely for the gripping thereof. Basically, the method according to the present invention makes use of image recognition in a practical manner. The initial gripper, first gripper, second gripper and / or clamp can be displaced and / or actuated based upon the determined position and / or orientation of at least one corner of the flatwork item. The step wherein the flatwork item is dropped from at least the initial gripper results in a rearrangement of the flatwork item which enables speeding up of the last steps of the method. In practice it can happen that after gripping the first corner and subjecting the flatwork item to further method steps to get the second corner, that parts of the flatwork item get folded, crossed and / or twisted. It is for example possible that the gripper grips the first corner in an incorrect orientation. It is time consuming to detect and correct such orientation error. The latter can for example be done by moving or rotating at least part of the gripper such that the orientation of the (corner of the) flatwork item is corrected. As indicated above, the correct orientation of the (corners of the) flatwork item is needed to provide a qualitative acceptable output. Due to the drop of the flatwork item, and thus the rearrangement thereof, the first and second corner can always be gripped in the desired orientation. Overall this results in an increased speed for detecting and gripping of the first and second corner in the correct orientation, resulting a higher output of processed flatwork items.

[0020] The steps of the method according to the present invention are typically successive steps. Capturing of at least one image can for example be done by visual imaging means or a visual imaging device. This can be any conventional visual imaging means, non-limiting examples thereof are a 2D camera and a 3D camera. When it is referred to a flatwork item, this can be type of conventional flatwork item. Nonlimiting examples of flatwork items according to the present invention are towels, cloths, (bed) sheets, napkins, bed linen, duvets, tabletops and / or pillowcases. Such flatwork item is typically substantially rectangular or square. Typically, the flatwork item has at least one corner, preferably at least two corners, and more preferably the flatwork item has four corners. The flatwork item is typically at least partially made of a textile or fabric, which can be either woven or nonwoven. However, it is also conceivable that the flatwork item is a garment. Hence, further non-limiting examples of the flatwork item are a top, shirt, blouse, sweater, trousers and / or a dress. With respect to the present invention, the term corner is just exemplary, this can also be any predetermined part or area of the flatwork item. Non-limiting examples thereof are an edge, corner region, shoulder part, collar, sleeve, button and / or zipper. Hence, the invention also relates to a method for detecting and gripping a predetermined part of a flatwork item, wherein a predetermined part of a flatwork is determined making use of imaging and subsequently gripped by at least one gripper.

[0021] The method could also include the step of picking at least one or a single flatwork item from multiple flatwork items. The method may for example comprise the steps of providing a plurality of flatwork items, picking at least one flatwork item from the plurality of flatwork items by at least one picker, positioning the at least one flatwork item upon a carrying structure, capturing or taking at least one image of at least part of at least one corner, in particular at least one first corner, of the at least one flatwork item, determining a position and / or orientation of a first corner of the at least one flatwork item in particular by means of at least one processor and gripping the determined first corner of the at least one flatwork item by at least one initial gripper. At least one picker can for example comprise at least one hook. Such embodiment can easily drop the at least one flatwork item upon a carrying structure. At least one picking may also comprise a clamp and / or a gripper. At least one picker can be configured to randomly pick at least one flatwork item from a plurality of flatwork items. At least one initial gripper may grip the at least one flatwork item from the carrying structure. At least one carrying structure may be formed by or may comprises at least one conveyor. The use of at least one conveyor can further speed up the method. The conveyor may for example be used to displace the at least one flatwork item to a capturing location. It is also possible that the conveyor is applied to transport the at least one flatwork item back into the initial pile of flatwork items, for example in case at least one corner cannot be detected or in case the detected corner is difficult to grip.

[0022] The processor may make use of at least one neural network, an Al system and / or deep learning model. It is possible that the method comprising the steps of providing at least one neural network at least one Al system and / or at least one deep learning model which is trained to recognize at least one corner of a flatwork item in an image and to indicate the position and / or orientation of said at least one corner, capturing at least one image of at least part of the at least one flatwork item, providing the at least one image to the at least one neural network, , an Al system and / or deep learning model receive a position and / or orientation of a first corner of the at least one flatwork item from the at least one processor and displacing at least one (initial and / or first) gripper towards the determined first corner of the flatwork item.

[0023] At least one carrying surface is in a possible embodiment at least partially permeable to air. It is for example possible that at least one carrying surface has a substantially open configuration. The carrying surface for example comprises at least one air opening. This may enable that air is expelled from underneath the carrying surface and / or that air is sucked towards the area underneath the carrying surface. It is for example possible that air is expelled from underneath the carrying surface such that at least part of the at least one flatwork item is partially lifted. The method may include the step of at least partially lifting of the at least one flatwork item positioned upon the carrying surface by air. This is preferably done after release of the flatwork item by the at least one initial gripper and / or prior to the first and / or second corners are determined. It is also conceivable that at least one air knife is used in order to assist the positioning of the flatwork item onto the carrying surface and / or when removing the flatwork item from the carrying surface.

[0024] At least one carrying surface preferably comprises at least one conveyor. It is also possible that at least one carrying surface is formed by or forms part of at least one conveyor. The use of at least one conveyor can further positively contribute to the operational speed of the system or the speed of the method, as a conveyor enables a continuous throughput or displacement of flatwork items between several sections of the system and / or steps of the method. It is also possible that the conveyor is applied to transport the at least one flatwork item back into the initial pile of flatwork items, for example in case at least one corner cannot be detected or in case the detected corner is difficult to grip. The conveyor can thereto transport the at least one flatwork item into a rotatable drum which enables controlled displacement of the flatwork item.

[0025] It is for example also possible that the at least one carrying surface comprises at least two adjacent conveyors, wherein each conveyor is individually operable. At least two conveyors can be positioned in line with each other, wherein at least one flatwork item is displaced from a first conveyor to a second conveyor. In an optional embodiment, at least one conveyor comprises multiple parallel belts. Such conveyor has a relatively open configuration.

[0026] At least one first gripper may be a vacuum gripper. It is also conceivable that at least one second gripper is a vacuum gripper. At least one vacuum gripper can for example be configured for gripping at least part of at least one corner by making use of an air flow. The gripping step of gripping the first and / or second corner may include the steps of lifting the corner of the at least one flatwork item via suction or the intake of air, and gripping the corner via a enclosing at least part of the second corner by the (initial, first and / or second) gripper, in particular by a clamping element thereof. Hence, the first gripper and / or the second gripper may comprise a suction element in combination with a (movable) clamping element. Lifting of the corner of the flatwork item via suction can for example be done by applying a vacuum. With suction, typically suction of air is meant. The suction is preferably temporarily and may be stopped once the second corner is gripped by the second gripper. The clamping element can for example be a gripping mouth. The combination of lifting and gripping of a corner enables that an item of flatwork, which is mostly a textile or the like, can be gripped in a controlled manner. Due to the flatwork item typically being made of a textile or fabric it is difficult to grip a corner which is positioned on a substantially flat surface, such as a carrying surface.

[0027] At least one initial gripper may for example be a Coanda gripper. The Coanda gripper preferably makes use of the lifting force of air in order to (temporarily) lift the flatwork item, such that the item can be gripped. It is for example conceivable that the initial gripper makes use of compressed air and / or pressurized air. The Coanda gripper can ensure that only the top layer of the flatwork item is gripped, for example when multiple parts of the flatwork item are engaged and / or sticked together.

[0028] Displacing the at least one flatwork item onto at least one carrying surface and releasing the at least one flatwork from the at least one initial gripper and / or the at least one clamp in particular is particular done such that at least the first corner and the second corner of the at least one flatwork item are positioned upon the at least one carrying surface, preferably in an aligned configuration wherein at the edge between the first and the second corner is substantially stretched and / or elongated. It is conceivable that displacing the at least one flatwork item onto at least one carrying surface is performed by the at least one initial gripper, wherein the at least one initial gripper substantially drags the at least one flatwork item over the carrying surface. In this way, the flatwork item can be spread out over at least part of the carrying surface in a relatively simple and effective manner. Dragging the flatwork item over the carrying surface via the gripped first corner whilst the second corner is hanging free enables the effective positioning of the flatwork item such that the first and second corner are freely exposed. The dragging movement can prevent that the corners of the at least one flatwork item will get flipped, folded and / or twisted.

[0029] In a preferred embodiment, the carrying surface comprises at least one conveyor, and the at least one flatwork item is positioned upon the carrying surface such that the edge defined by the first corner and the second corner of the at least one flatwork item is positioned under an angle with respect to the transport direction of the at least one conveyor, and preferably the edge is positioned substantially perpendicular to the transport direction of the at least one conveyor. In this way, the flatwork item can be effectively transported between processing steps. It is for example possible that the flatwork item is transported from a dropping location to a detection and / or gripping location. In a possible embodiment, it is conceivable that the transport direction is transports the outer end opposing the first edge of the flatwork item first. The flatwork item can basically be transported backwards within the system.

[0030] It is possible that the first corner is dropped during displacement thereof by the at least one initial gripper. At least one initial gripper preferably releases the at least one flatwork item such that at least the first corner of the at least one flatwork item makes a drop. Said drop is preferably at least 150 mm, more preferably at least 200 mm, most preferably at least 250 mm and / or of at most 450 mm, preferably at most 400 mm, more preferably at most 350 or 300 mm. Such drop can be sufficient to detangle and / or twist the corner such that the corner is positioned substantially flat upon the carrying surface. It is also possible that the flatwork item makes a drop of at most 250 or at most 200 mm or even at most 100 mm. Alternatively, it is conceivable that at least one initial gripper releases the at least one flatwork item such that at least the first corner of the at least one flatwork item makes a drop of at least 5 mm, at least 10 mm, more preferably at least 50 mm or 100 mm. It is conceivable that the clamp retains the flatwork item during the displacement and may optionally provide tension to the flatwork item. After the flatwork item is dropped, the first corner and the second corner are positioned upon the at least one carrying surface. Subsequently, the position and / or orientation of the corners can be determined such that the corners can be gripped. The second corner is gripped for the first time, the first corner is gripped for a second time.

[0031] It is conceivable that the first corner of the at least one flatwork item is gripped by multiple initial grippers, wherein at least one initial gripper acts as buffer gripper. It is also conceivable that a secondary initial gripper takes over the first corner after the first gripping step and / or prior to the displacing onto the carrying surface. It also possible that multiple buffer grippers are applied. The use of multiple grippers can significantly speed up the overall process of feeding a flatwork items to a transport conveyor and / or a flatwork treating device. It may further contribute to enabling continuous application of the method and / or increasing the output of flatwork items fed to a subsequent step. The buffers grippers can be substantially equal in their technical construction. It is however also conceivable that a secondary initial gripper and / or a tertiary initial gripper has a different design from the at least one initial gripper.

[0032] It is possible that multiple images are captured of at least part of the at least one flatwork item, and wherein each image is annotated with information about a position and / or orientation of at least one corner of the at least one flatwork item. The annotated images of flatwork items may be saved by the processor and / or by a neural network, an Al system and / or deep learning model.

[0033] It is conceivable that the method comprises the step of lifting at least part of the at least one flatwork item by the at least one first gripper and the at least one second gripper such that the flatwork item is flipped in its orientation prior to the at least one flatwork item is fed to a transport conveyor and / or a flatwork treating device. It is for example possible that the at least one flatwork is flipped 180 degrees. The upper side of the flatwork item in the configuration wherein the corners were detected in the imaging step can then be facing downwards. It can be beneficial to flip the orientation when feeding the flatwork items to a transport conveyor and / or a flatwork treating device as this step can achieve that the flatwork item as such is spread out evenly and / or in its unfolded configuration.

[0034] The method may include the steps of determining if the gripping of the determined first and / or corner by the initial gripper, the first gripper or the second gripper was successful and discharging the flatwork item from the system if the grip was classified as unsuccessful. A gripping action can be classified as successful if the corner is gripped in clamping configuration, preferably without any folds and / or irregularities in the material of the flatwork item.

[0035] It possible that the method includes the step of shaking the flatwork item preferably such that a second corner which is at shortest distance from the first corner will hang free. This can be done prior to the clamp grabs part of the flatwork item or after grabbing thereof.

[0036] The invention also relates to a system for feeding a flatwork item to a transport conveyor and / or a flatwork treating device by making use of a method according to the present invention. The system according to the invention is configured for feeding a flatwork item, such as a towel, cloth, bed sheet, napkin, bed linen, duvet, tabletop and / or pillowcase, to a transport conveyor and / or a flatwork treating device, preferably via a method according to the present invention, said system comprising:

[0037] - at least one displaceable initial gripper configured for gripping at least part of at least one flatwork item, in particular at least one corner of the at least one flatwork item flatwork item;

[0038] - optionally at least one clamp configured for retaining at least part of the at least one flatwork item;

[0039] - at least one displaceable first gripper configured for gripping a first corner of the at least one flatwork item;

[0040] - at least one displaceable second gripper configured gripping a second corner of the at least one flatwork item; - at least one carrying surface configured for carrying at least part of at least one flatwork item;

[0041] - at least one visual imaging device configured for capturing images of at least part of the at least one flatwork item; and

[0042] - at least one processor configured for determining at least one parameter of at least part of the at least one flatwork item based upon at least one captured image and configured to displace the at least one initial gripper, the at least one clamp, the at least one first gripper and / or the at least one second gripper based on at least one determined parameter.

[0043] The system according to the invention benefits of the same advantages as described for the method according to the present invention. The embodiments described for the method apply to the system and vice versa.

[0044] The system may further comprise at least one picker configured to pick at least one flatwork item from a plurality of flatwork items. It is for example possible that the at least one picker is configured to pick at least one flatwork items from a pile of flatwork items.

[0045] At least one processor is in particular configured for determining a position and / or orientation of at least part of the at least one flatwork item based upon at least one captured image and configured to displace the at least one picker, the at least one initial gripper, the at least one clamp, the at least one first gripper and / or the at least one second gripper based on the determined position and / or orientation. It is possible that the at least one processor work by means of at least one neural network, an Al system and / or deep learning model. It is also conceivable that the at least one processor comprises at least one neural network at least one Al system and / or at least one deep learning model, wherein the at least one neural network, the at least one Al system and / or the at least one deep learning model is trained to recognize at least one corner of at least one flatwork item in at least one image and to indicate a position and / or orientation of said at least one corner. The system may further comprise at least one drive unit for displacing the at least one picker, the at least one initial gripper, the at least one clamp, the at least one first gripper and / or the at least one second gripper. It is possible that the at least one drive unit is controlled and / or activated by the at least one processor. The at least one picker, the at least one initial gripper, the at least one clamp, the at least one first gripper and the at least one second gripper are all configured to clamp, grip or grasp at least part of at least one flatwork item. Based on the actual function of the gripper, clamp or picker the design thereof can be determined. The at least one initial gripper, the at least one first gripper and / or the at least one second gripper preferably comprise a gripping mouth configured to enclose at least part of a corner of the flatwork item. It is also conceivable that the at least one initial gripper, the at least one first gripper and / or the at least one second gripper and in particular the gripping mouth thereof if applied, is rotatable over at least 180 degrees, preferably 360 degrees, over an axis of rotation. The at least one initial gripper, the at least one first gripper and / or the at least one second gripper may be configured for lifting at least part of the at least one flatwork item, and in particular of the corner before gripping it. The at least one initial gripper, the at least one first gripper and / or the at least one second gripper may also comprise at least one telescopic arm or multiple telescopic arms.

[0046] At least part of the at least one carrying surface may be permeable to air. The carrying surface can for example comprises at least one air opening and / or may be at least partially configured by a mesh or mesh structure. Hence, the carrying surface can enable that a flow of air through the carrying surface can be applied. This can be either attract (draw or pull) the flatwork item towards the carrying surface, or push (at least part of) the flatwork item away from it. This can be beneficial for controlling the motion or motionlessness of the flatwork item. Typically, the carrying surface is at least partially substantially flat. A substantially flat carrying surface can provide improved support of the flatwork item.

[0047] In a beneficial embodiment, at least one carrying surface comprises at least one conveyor. The use of at least one conveyor can further increase the throughput or displacement of flatwork items between several sections of the system. The at least one conveyor is preferably controllable by the at least one processor. In case the processor for example notices that the correct position and / or orientation of the at least one flatwork item cannot be determined correctly or in case the flatwork item is not in the desired orientation, the processor can reject the flatwork item and the conveyor can reject and / or discard the flatwork item and remove it from the main processing route. It is for example also possible that the at least one carrying surface comprises at least two adjacent conveyors, wherein each conveyor is individually operable. At least two conveyors can be positioned in line with each other, wherein at least one flatwork item is displaced from a first conveyor to a second conveyor. It is possible that the positioning of the at least one flatwork item is done on the first conveyor whilst the identification of the corners of the flatwork item is done upon the second conveyor. In an optional embodiment, at least one conveyor comprises multiple parallel belts. Such conveyor has a relatively open configuration.

[0048] The system may also comprise at least one additional conveyor. Such conveyor It is also possible that the conveyor is applied to transport the at least one flatwork item back into the initial pile of flatwork items, for example in case at least one corner cannot be detected or in case the detected corner is difficult to grip. The conveyor can thereto transport the at least one flatwork item into a rotatable drum which enables controlled displacement of the flatwork item. It is conceivable that multiple of such conveyors are applied. For example in the bottom region of the system.

[0049] The system may comprise at least one rotatable drum. The at least one rotatable drum may comprise at least one contact surface and at least one receiving volume. It is conceivable that the at least one rotatable drum is positioned at a distal end of the at least one carrying surface and / or the at least one conveyor thereof. In this way, the rotatable drum can receive at least part of the flatwork item in the receiving volume when the flatwork item is rejected, for example in case the gripping of the corners by the first and / or second gripper was incorrect. The contact surface of the rotatable drum can be applied as aid for displacing of the at least one flatwork item. It is for example conceivable that the contact surface is applied to facilitate contact prior to and / or during the lifting and / or flipping of the at least one flatwork item onto a transport conveyor.

[0050] Preferably, the at least one picker, the at least one initial gripper, the at least one clamp, the at least one first gripper and / or the second gripper are independently movable and controllable. In this way, further controlled operation of the flatwork items can be achieved. The system may comprise at least one buffer gripper, and preferably multiple buffer grippers. At least one buffer gripper can for example be configured to take over the first corner after the first gripping step and / or prior to the displacing onto the carrying surface. The buffers grippers can be substantially equal in their technical construction. It is however also conceivable that a secondary initial gripper and / or a tertiary initial gripper has a different design from the at least one initial gripper.

[0051] The visual imaging device can be any conventional visual imaging means, nonlimiting examples thereof are a 2D camera and a 3D camera. At least one visual imaging device comprises a camera and / or may be formed by a camera. The system may comprise multiple visual imaging devices. Preferably at least one visual imaging device is applied at a section where at least one clamp or gripper is applied.

[0052] Possibly the system comprises at least one air knife. An air knife can be applied in order to control and / or guide the position and / or orientation of the flatwork item in a relatively simple and reliable manner.

[0053] The invention also relates to use of a system according to the present invention.

[0054] Within the context of the present invention, when it is referred to a system for feeding a flatwork item to a transport conveyor and / or a flatwork treating device, also a device for feeding a flatwork item to a transport conveyor and / or a flatwork treating device can be meant.

[0055] The invention will be further elucidated by means of non-limiting exemplary embodiments illustrated in the following figures, in which:

[0056] - figure 1 shows a schematic representation of the method according to the present invention; and

[0057] - figures 2a-2e show perspective views of a possible embodiment of a system according to the present invention.

[0058] Within these figures, similar reference numbers correspond to similar or equivalent elements or features.

[0059] Figure 1 shows a schematic representation of the method steps as applied in the method according to the present invention in particular using a system according to the present invention. The figure shows a sequence of steps wherein a flatwork item 101 , such as a towel, cloth, bed sheet, napkin, bed linen, duvet, tabletop and / or pillowcase is picked by two of its corners such that it can be fed to a transport conveyor and / or a flatwork treating device. At first, multiple flatwork items 101 are provided. In the shown schematic visualization, a pile of flatwork items 101 whereof a single flatwork item 101 is picked by a picker 102. At least part of the picker 102 can be hook shaped. In the shown embodiment, the picker 102 drops or positions the flatwork item 101 upon a carrying structure 103. Additionally or alternatively, a further gripper (not shown) grips the flatwork item 101 which is picked up by said picker 102, and subsequently drops or positions the flatwork item 101 upon said carrying structure 103. The further gripper (not shown) may take over the flatwork item 101 or the picker 102 and the additional gripper jointly drop or position the flatwork item 101 upon said carrying structure 103. In the shown embodiment, the carrying structure 103 comprises an endless belt. An imaging device 104a is applied which captures an image of at least part of the flatwork item 101. This is done to enable the detection of at least one corner thereof. There is typically made use of at least one processor to determine a possible position and / or orientation of a first corner of the flatwork item 101 . In the figure, the first corner of the flatwork item is identified in the area of the dotted lines. Subsequently, the determined first corner of the flatwork item 101 is gripped by at least one initial gripper 105. After the first corner has been gripped, the flatwork item 101 is hanging down from said first corner. In this configuration, at least one further corner and possibly each further corner of the flatwork item 101 substantially hangs free. Optionally, the initial gripper 105 transfers the flatwork item 101 to a second initial gripper 105a, such that the flatwork item 101 is hanging down from a gripping area, in particular (close to) the first corner, gripped by the second initial gripper 105a. The second initial gripper 105a may grip the flatwork item 101 at an angle with respect to the initial gripper 105. A further part of the flatwork item 101 is then retained by a clamp 106. This clamping action is done at a distance from the first corner. It is possible that an imaging device 104b, optionally in combination with a processor, is applied to determine a suitable position for the clamp to grip the flatwork item. Subsequently, the clamp 106 can lift at least part of the flatwork item 101 such that at least one second corner of the flatwork item 101 which is adjacent to the first corner substantially hangs free. This is beneficial as this positively contributes to the further handling of the flatwork item 101. The flatwork item is in particular spread out and position upon a carrying surface 107. Subsequently, the flatwork item 101 is released from the initial gripper 105 or the second initial gripper 105a and from the clamp 106. The first corner and second corner are free of any gripping means and as such positioned upon the carrying surface 107. Imaging devices 104c, 104d are then applied for capturing at least one image of at least part of the first corner and at least one image of at least part the second corner of the flatwork item 101. The dotted lines in the figure indicate the position of the respective first and second corner. The position and / or orientation of the first corner and the possible position and / or orientation of the second of the flatwork item 101 are then determined, in particular by means of at least one processor which uses the input of the imaging device(s) 104c, 104d. Once the position of the first and second corner of the flatwork item 101 is clear, the determined first corner is gripped by at least one first gripper 108 and the determined second corner is gripped by at least one second gripper 109. The first gripper 108 and second gripper 109 can be applied for feeding the flatwork item 101 to a transport conveyor and / or a flatwork treating device (not shown). The first gripper 108 and second gripper 109 can for example be vacuum grippers.

[0060] Figures 2a-2c show perspective views of a possible embodiment of a system 200 according to the present invention. Each figure shows a different side view of the system 200. Figures 2d and 2e shown detailed parts of the system 200. The sections A-F of the system 200 which relate to the specific method steps are indicated with dotted lines. The system 200 is configured for feeding a flatwork item to a transport conveyor 210 and / or a flatwork treating device in particular via a method according to the present invention. In section A, the flatwork items can be picked. The system 200 comprises thereto at least one picker 202 for picking flatwork items. After the flatwork item is picked, the item is positioned upon a carrying structure 203. This location is seen in section B. The imaging device 204a positioned above the carrying structure 203 can take images of the flatwork item. A displaceable initial gripper 205 is configured for gripping at least part of at least one flatwork item, in particular at least one corner of the at least one flatwork item flatwork item. Optionally, the system 200 further comprises a second initial gripper 205a configured to receive the flatwork item from the initial gripper 205. The flatwork item is then hanging down from said first corner in section C. In this configuration, at least one further corner and possibly each further corner of the flatwork item substantially hangs free. A further part of the flatwork item is preferably retained by a clamp 206 in that section. The flatwork item is then displaced to section D where the flatwork item is in particular spread out and position upon a carrying surface 207. Subsequently, the flatwork item is released from the initial gripper 205 or the second initial gripper 205a and from the clamp 206. In section D, preferably at the second conveyor thereof, images are captured, in particular by an imaging device 204b, of at least part of the first corner and at least one image of at least part the second corner of the flatwork item. The position and / or orientation of the first corner and the possible position and / or orientation of the second of the flatwork item are then determined, in particular by means of at least one processor which uses the input of the imaging device(s). The determined first corner is gripped by at least one first gripper 208 and the determined second corner is gripped by at least one second gripper 209. Section D, may further comprise at least one, preferably at least two additional grippers 215 and 216 configured for transporting a flatwork item from section B to section D. Optionally, at least one, optionally at least two, additional gripper 215, 216 may be configured to co-act with the second initial gripper 205a and / or with the clamp 206 or to transfer the flatwork item between the second initial gripper 205a and the clamp 206. In section E, the flatwork item is fed to a transport conveyor. The system 200 comprises at least one rotatable drum 211 which comprises at least one contact surface 213 and at least one receiving volume 212. The rotatable drum 211 is positioned at a distal end of the at least one carrying surface 207 and in particular of the at least one conveyor thereof. In this way, the rotatable drum 211 can receive at least part of the flatwork item in the receiving volume 212 when the flatwork item is rejected, for example in case the gripping of the corners by a first 208 and / or second gripper 209 was incorrect. The contact surface 213 of the rotatable drum 211 can be applied as aid for displacing of the at least one flatwork item and in particular to facilitate contact prior to and / or during the displacement of the at least one flatwork item onto a transport conveyor. Section F shows that there is an additional conveyor 214 at the bottom region of the system 200 configured for displacing flatwork items which are dropped within the system. The flatwork items are then returned to section A where they can be picked again by the picker.

[0061] Figures 2d and 2e show detailed parts of the carrying surface 207 and the rotatable drum 211 according to the invention in an isolated configuration. The carrying surface comprises two conveyors 207a, 207b which are independently controllable.

[0062] The rotatable drum 211 is positioned at the distal end of the second conveyor 207b.

[0063] It will be clear that the invention is not limited to the exemplary embodiments which are illustrated and described here, but that countless variants are possible within the framework of the attached claims, which will be obvious to the person skilled in the art. In this case, it is conceivable for different inventive concepts and / or technical measures of the above-described variant embodiments to be completely or partly combined without departing from the inventive idea described in the attached claims.

[0064] The verb 'comprise' and its conjugations as used in this patent document are understood to mean not only 'comprise', but to also include the expressions 'contain', 'substantially contain', 'formed by' and conjugations thereof.

[0065] When the word ‘gripping’ is used, also the terms grasping, picking, holding, grabbing and / or clasping can be meant. When it is referred to a corner of a flatwork item, the point where two edges of the flatwork item meet is meant. It also possible that the corner is a shoulder part of for example a shirt or (bath)robe. The corner is typically gripped by double sided engagement of the textile. The position and / or orientation of the first image can be determined in both a 2D and / or 3D configuration. The first and second grippers are typically also configured for releasing the gripped part of the flatwork item after their step according to the invention is fulfilled.

Claims

Claims1 . Method for feeding a flatwork item, such as a towel, cloth, bed sheet, napkin, bed linen, duvet, tabletop and / or pillowcase, to a transport conveyor and / or a flatwork treating device, comprising the steps of:- providing at least one flatwork item;- capturing at least one image of at least part of the at least one flatwork item, in particular of at least one first corner of the at least one flatwork item;- determining a position and / or orientation of a first corner of the at least one flatwork item in particular by means of at least one processor;- gripping the determined first corner of the at least one flatwork item by at least one initial gripper such that at least one further corner and preferably each further corner of the at least one flatwork item substantially hangs free;- retaining at least part of the at least one flatwork item at a distance from the first corner by at least one clamp and lifting at least part of the at least one flatwork item such that at least one second corner of the at least one flatwork item which is adjacent to the first corner substantially hangs free;- displacing the at least one flatwork item onto at least one carrying surface and releasing the at least one flatwork from the at least one initial gripper such that at least the first corner and the second corner of the at least one flatwork item are positioned upon the at least one carrying surface;- capturing at least one image of at least part of the first corner and at least one image of at least part the second corner of the at least one flatwork item;- determining a position and / or orientation of the first corner of the at least one flatwork item and a position and / or orientation of the second corner of the flatwork item by means of at least one processor;- gripping the determined first corner of the at least one flatwork item by at least one first gripper and gripping the determined secondcorner of the at least one flatwork item by at least one second gripper; and- feeding the at least one flatwork item to a transport conveyor and / or a flatwork treating device via the at least one first gripper and / or the at least one second gripper.

2. Method according to claim 1 , wherein the steps are successive steps.

3. Method according to any of the previous claims, comprising the steps of:- providing a plurality of flatwork items;- picking at least one flatwork item from the plurality of flatwork items by at least one picker;- positioning the at least one flatwork item upon a carrying structure;- capturing at least one image of at least part of at least one corner, in particular at least one first corner, of the at least one flatwork item;- determining a position and / or orientation of a first corner of the at least one flatwork item in particular by means of at least one processor; and- gripping the determined first corner of the at least one flatwork item by at least one initial gripper.

4. Method according to any of the previous claims, wherein the at least one carrying surface is at least partially permeable to air.

5. Method according to any of the previous claims, wherein the at least one carrying surface comprises at least one conveyor.

6. Method according to claim 5, wherein the at least one carrying surface comprises at least two adjacent conveyors, wherein each conveyor is individually operable.

7. Method according to claim 5 or claim 6, wherein at least one conveyor comprises multiple parallel belts.

8. Method according to any of the previous claims, wherein the at least one first gripper is a vacuum gripper and / or wherein the at least one second gripper is a vacuum gripper.

9. Method according to any of the previous claims, wherein displacing the at least one flatwork item onto at least one carrying surface is performed by the at least one initial gripper, wherein the at least one initial gripper substantially drags the at least one flatwork item over the carrying surface.

10. Method according to claim 5 and claim 9, wherein the at least one flatwork item is positioned upon the carrying surface such that the edge defined by the first corner and the second corner of the at least one flatwork item is substantially perpendicular to the transport direction of the at least one conveyor.11 . Method according to any of the previous claims, wherein the at least one initial gripper releases the at least one flatwork item such that at least the first corner of the at least one flatwork item makes a drop preferably of at least 150 mm, preferably at least 200 mm, more preferably at least 250 mm.

12. Method according to any of the previous claims, wherein the first corner of the at least one flatwork item is gripped by multiple initial grippers, wherein at least one initial gripper acts as buffer gripper.

13. Method according to any of the previous claims, comprising the step of lifting at least part of the at least one flatwork item by the at least one first gripper and the at least one second gripper such that the flatwork item is flipped in its orientation prior to the at least one flatwork item is fed to a transport conveyor and / or a flatwork treating device.

14. System for feeding a flatwork item, such as a towel, cloth, bed sheet, napkin, bed linen, duvet, tabletop and / or pillowcase, to a transport conveyor and / or a flatwork treating device, preferably via a method according to any of the previous claims, comprising:- at least one displaceable initial gripper configured for gripping at least part of at least one flatwork item, in particular at least one corner of the at least one flatwork item;- at least one clamp configured for retaining at least part of the at least one flatwork item;- at least one displaceable first gripper configured for gripping a first corner of the at least one flatwork item;- at least one displaceable second gripper configured gripping a second corner of the at least one flatwork item;- at least one carrying surface configured for carrying at least part of at least one flatwork item;- at least one visual imaging device configured for capturing images of at least part of the at least one flatwork item; and- at least one processor configured for determining at least one parameter of at least part of the at least one flatwork item based upon at least one captured image and configured to displace the at least one initial gripper, the at least one clamp, the at least one first gripper and / or the at least one second gripper based on at least one determined parameter.

15. System according to claim 14, comprising at least one picker configured to pick at least one flatwork item from a plurality of flatwork items.

16. System according to claim 14 or claim 15, wherein the at least one processor is configured for determining a position and / or orientation of at least part of the at least one flatwork item based upon at least one captured image and configured to displace the at least one initial gripper, the at least one clamp, the at least one first gripper and / or the at least one second gripper based on the determined position and / or orientation.

17. System according to any of claims 14-16, comprising at least one drive unit for displacing the at least one initial gripper, the at least one clamp, the at least one first gripper and / or the at least one second gripper.

18. System according to any of claims 14-17, wherein the at least one processor comprises at least one neural network, at least one Al system and / or atleast one deep learning model, wherein the at least one neural network, the at least one Al system and / or the at least one deep learning model is trained to recognize at least one corner of a flatwork item in an image and to indicate the position and / or orientation of said at least one corner.

19. System according to any of claims 14-18, wherein the at least one carrying surface is at least partially permeable to air.

20. System according to any of claim 14-19, wherein the at least one carrying surface comprises at least one conveyor.21 . System according to claim 20, wherein the at least one carrying surface comprises at least two adjacent conveyors, wherein each conveyor is individually operable.

22. System according to any of claims 14-21 , wherein the at least one initial gripper, the at least one clamp, the at least one first gripper and the second gripper are independently movable and controllable.

23. System according to any of claims 14-22, comprising at least one buffer gripper.

24. System according to any of claims 14-23, wherein the at least one visual imaging device comprises a camera.

25. System according to any of claims 14-24, comprising at least one air knife.

26. System according to any of claims 14-25, comprising at least one rotatable drum which comprises at least one contact surface and at least one receiving volume.

27. Use of a system according to any of claims 14-26.

Images