Method for the robot-assisted sewing of multiple fabric layers

Abstract

The present invention relates to a method for the robot-assisted sewing of fabric layers (111, 112) for garments. The method comprises gripping a first fabric layer (111) with a handling mechanism (120) of a handling robot (100) having an effector (101) for handling fabric layers (111, 112). The first fabric layer (111) is positioned over a second fabric layer (112), which is placed on a worktable (103), and the first fabric layer (111) is fixed to the second fabric layer (112) so as to form a fabric layer stack (113) by means of a fixing mechanism (130) which is at least in part arranged on the effector (101) in such a way that a joining region (114) of the first fabric layer (111) rests on a further joining region (115) of the second fabric layer (112). Furthermore, the fabric layer stack (113) is fed to a sewing machine (140) by means of the handling mechanism (120), the joining regions being freely accessible to said sewing machine (140). The joining regions are sewn together, the handling mechanism (120) guiding the fabric layer stack (113) relative to the sewing machine (140) during sewing. The sewn fabric layer stack (113) is fed from the sewing machine (140) to a depositing location by means of the handling mechanism (120).

Description

[0001] Method for robot-assisted sewing of multiple layers of fabric

[0002] Technical area

[0003] The present invention relates to a method and a system for robot-assisted sewing of fabric layers.

[0004] Background of the invention

[0005] In the technical field of textile processing, one goal is to increase the level of automation in order to reduce personnel costs and, accordingly, production costs.

[0006] A textile processing system, for example, designed for automated sewing, requires a handling mechanism to separate the fabric from a stack and, after manipulation, feed it into a sewing system (or sewing machine) at a sufficient distance. For this purpose, robots with an effector are used, on which appropriate gripping mechanisms are arranged to grasp the textile piece. However, fabric pieces that constitute a garment have different sizes and can have different properties (thickness, air permeability, stiffness, etc.) both among themselves and within the same piece.

[0007] During sewing with a sewing machine, two superimposed layers of fabric are moved relative to the sewing machine to create a seam. The fabric layers can be moved by the sewing machine itself or by a special guide unit that guides the fabric layers relative to the sewing machine. Before and after the sewing process, additional handling elements must be used to feed and remove the fabric layers. This means that a longer setup time is required before and after the sewing process before a sewing process can begin.

[0008] It is an object of the present invention to increase the efficiency of an automatic sewing process.

[0009] This object is achieved by a method and a system for robot-assisted sewing of fabric layers according to the subject matter of the independent patent claims.

[0010] According to a first aspect of the present invention, a method for robot-assisted sewing of fabric layers for clothing is described. The method comprises gripping a first fabric layer with a handling mechanism of a handling robot having an effector for handling fabric layers. The first fabric layer is positioned over a second fabric layer resting on a work table, and the first fabric layer is fixed to the second fabric layer to form a fabric layer stack by means of a fixing mechanism arranged at least partially on the effector, such that a joining region of the first fabric layer rests on another joining region of the second fabric layer. Furthermore, the fabric layer stack is fed to a sewing machine by means of the handling mechanism, wherein the joining regions are freely accessible to the sewing machine.The joining areas are sewn, with the handling mechanism guiding the stack of fabric layers relative to the sewing machine during sewing. The sewn stack of fabric layers is fed from the sewing machine to a storage location by means of the handling mechanism. According to a further aspect, a system for robot-assisted sewing of fabric layers for clothing is described. The system comprises a handling robot with an effector, which has a handling mechanism for handling fabric layers, wherein the handling mechanism is designed to grip a first fabric layer. The handling mechanism is configured to position the first fabric layer over a second fabric layer resting on a work table.

[0011] The system further comprises a fixing mechanism which is arranged at least partially on the effector, wherein the fixing mechanism is configured to fix the first fabric layer and the second fabric layer to one another to form a fabric layer stack such that a joining region of the first fabric layer rests on another joining region of the second fabric layer. The system further comprises a sewing machine. The handling mechanism is configured to feed the fabric layer stack to the sewing machine, wherein the joining regions are freely accessible to the sewing machine. The sewing machine is configured to sew the joining regions, wherein the handling mechanism is configured to guide the fabric layer stack relative to the sewing machine during the sewing process.

[0012] The handling mechanism is configured to transport the sewn fabric stack from the sewing machine to a storage location.

[0013] The handling robot has the effector, to which the corresponding handling mechanism is attached, particularly in an interchangeable manner. The handling robot is attached to the floor or workbench with a stationary robot base to introduce the corresponding forces into the corresponding system. Alternatively, the handling robot can also be configured such that the robot base is designed to be movable along the floor. A robot arm can be arranged between the effector and the robot base, which, for example, has one or more joints to thus steer the effector into a desired position.

[0014] The handling robot is a programmable, multipurpose handling device for moving material, workpieces, tools, or specialized equipment. Specifically, the handling robot is designed to handle or manipulate the layers of material and to move and position them accordingly. In other words, the handling robot enables machine-controlled position changes in more than one axis and / or along a translational position change of the layers of material.

[0015] The term fabric layer refers to the possible textiles or textile parts of a textile product, in particular a piece of clothing. The term fabric layer includes different types of knitted fabrics, in particular woven fabrics and nonwovens. The left / wrong side of a fabric layer is understood to be the inside (i.e. the underside of the fabric, inside of the fabric or the 'unsightly side' of a fabric layer. In a piece of clothing, the left side corresponds to the non-visible side of the fabric layer. The right / right side of a fabric layer refers to the 'sightly side' of a fabric or fabric layer (e.g. the top side of the fabric, visible side, outside of the fabric). In a piece of clothing, the right side corresponds to the visible side of the fabric or fabric layer (e.g. the outside of a T-shirt). Furthermore, a fabric part can consist of several layers of fabric.For example, a piece of fabric (such as a garment) can be folded over several times and lie on a work table as a stack of fabric layers with multiple layers of fabric. Alternatively, the fabric layers can each represent separate pieces of fabric that form a stack of fabric layers on top of one another. A joining area of ​​a fabric layer describes an area that is to be processed with a sewing machine. The joining area can, for example, be the area of ​​a fabric layer where a seam or hem can run. In particular, joining areas of two superimposed fabric layers are placed on top of one another so that they can be joined using the sewing machine (e.g., by sewing or welding).

[0016] The controllable handling mechanism and the fixing mechanism are arranged on the effector. The fixing mechanism is designed to fasten at least two layers of fabric, which in particular lie on top of one another, so that the fixed two layers of fabric can be conveyed, in particular, as a package or as a stack of fabric layers.

[0017] In particular, the handling mechanism can transport a layer of fabric or the described fixed-together layers of fabric, for example to the sewing machine. The effector or the handling mechanism can adapt to the contour of the layers of fabric, for example by adjusting the fixing points of the handling mechanism to which the layer of fabric is fixed. For example, the fixing elements described below can be arranged for this purpose, in which the individual fixing points are formed. The handling mechanism covers in particular the outline-relevant points of a contour of the layer of fabric, with one edge of the layers of fabric preferably remaining free as a joining area and not being covered by the handling mechanism. The area of ​​the layers of fabric that is covered by the effector or the handling mechanism for fixing the layers of fabric is referred to below as the effector contour.

[0018] In one exemplary embodiment, the fixation mechanism is arranged entirely on the effector. However, part of the fixation mechanism can also be arranged on a work table, on which, for example, the fabric layers are placed. Accordingly, the handling mechanism is completely attached to the effector, but part of the handling mechanism can also be attached to the work table. In exemplary embodiments, functional elements of the fixation mechanism can form elements of the handling mechanism and vice versa. For example, a holding needle device or suction device of the fixation mechanism can fix several fabric layers, but can also hold the thus formed fabric layer stack to the effector, thus also fulfilling the function of the handling mechanism.

[0019] The effector thus forms an end part of the handling robot with, for example, grippers as handling mechanisms, which grasp and manipulate a fabric layer (for example a flat, unprocessed fabric layer or an entire garment as a fabric layer) or a fabric layer stack consisting of fabric layers that are fastened with the fixing mechanism.

[0020] For example, the sewing machine can join two layers of fabric together, creating a seam. A seam, for example, describes the joining of two layers of fabric using a thread or yarn, with at least one material essentially being a fabric, a fleece, or a woven fabric.

[0021] For the automatic manufacturing of textile products, joining two layers of fabric is a fundamental requirement for many products, particularly in the manufacture of garments. For this purpose, according to the invention, two layers of fabric can be precisely positioned using the handling mechanism so that the joining areas lie exactly on top of one another and are fixed in place using the fixing mechanism. So that several pieces of fabric can be precisely stacked on top of one another using the effector and then fixed in place for further processing, the effector according to the invention allows a first layer of fabric to be laid down on a surface of a work table, a further layer of fabric to be precisely aligned and laid down on the layer of fabric already lying on the work table, and the two layers of fabric to be fixed in place using the fixing mechanism. The handling mechanism can be used to 'reposition a layer of fabric' and 'pile up'.

[0022] An inventive effector / gripper system equipped in this way is capable of precisely stacking fabric layers on top of one another so that these two fabric layers can then be joined. However, it can also be used to fold over a piece of fabric using the folding device described below, creating two fabric layers that can then be fixed and further processed (e.g., turning over a hem). To fix the two fabric layers to one another, preparatory measures can be carried out with the system even before placement. These can include folding (see the folding device described below), or adding (an adhesive), inserting (auxiliary material for ultrasonic welding), etc., as enabled by the fixing mechanism. Such a preparatory action is made possible according to the invention with an additional device or fixing mechanism, which is installed either on the effector or on the work table.

[0023] With the method and system according to the invention, the fabric layers can be held on the same effector by means of the handling mechanism throughout the entire handling process before and after sewing. Thus, no conversion between a feeding device before sewing and a device after sewing is necessary. Since the fabric layers are held together by means of the fixing mechanism before and during sewing and the handling mechanism fastens the fabric layers to the effector before, during and after sewing, no further conveying unit is necessary, thus providing a more efficient sewing process. According to a further exemplary embodiment of the method, the handling mechanism separates the second fabric layer from a plurality of fabric layers and places it flat on a work surface of the work table, so that the first fabric layer is subsequently positioned over the second fabric layer.In other words, a fabric layer is separated from a stack of fabric layers and then placed flat on the work surface. A second fabric piece is then grasped using the handling mechanism and placed on the second fabric layer with a defined overlap, particularly in the joining areas. This has the advantage that the effector can place the second fabric layer on a layer whose location is already precisely known (e.g., from a previous placement step).

[0024] According to a further exemplary embodiment, the first fabric layer and the second fabric layer form regions of a fabric part, wherein the positioning of the first fabric layer over the second fabric layer is achieved by folding the fabric part, in particular by means of a folding device which is configured to fold over an edge region of the fabric part such that the folded edge region forms the first fabric layer which rests on the second fabric layer. In particular, an excess length of a fabric layer which projects beyond the effector or the effector contour is folded over by means of a hem folder (folding device). This has the advantage that the fabric part only has to be gripped once by the handling mechanism (e.g. during separation), thus ensuring greater positioning reliability, which helps to reduce the error rate and the tendency to crease.The folding device is configured to fold over an edge region of a fabric layer such that the folded edge region forms the first fabric layer, which rests on top of the second fabric layer. The folding device is arranged, in particular, on the work table. The folding device has a clamping device arranged on the effector or on the work table, which is arranged, in particular, on the effector to clamp the folded first fabric layer and the second fabric layer together.

[0025] According to a further exemplary embodiment, the first fabric layer is fixed to the second fabric layer by means of temporary fixing elements, in particular holding pins, which are removed during sewing, in particular taking into account the sewing progress, or after sewing.

[0026] According to another exemplary embodiment, a work surface of the work table has adhesion zones with different levels of static friction. When positioning the first fabric layer, the second fabric layer, or the stack of fabric layers, the handling mechanism takes the different adhesion zones into account for aligning the first fabric layer, the second fabric layer, or the stack of fabric layers. In one exemplary embodiment, the adhesion of the adhesion zones can, in particular, be controllable. The work table can have zones of different levels of friction / adhesion. This difference can be permanent or switchable / adjustable and thus temporary. For example, it can be advantageous if the lower fabric layer does not slip during precise placement for fixation because it has a high level of friction / adhesion relative to the work surface (while the upper fabric layer is placed on top of it).Once both layers are fixed using the fixing mechanism, the robot can lift the fabric layers using the handling mechanism and reposition them in an area with better sliding properties for sewing, or the adhesion to the work surface can be eliminated.

[0027] According to a further exemplary embodiment, the sewing machine has a presser foot with a presser foot length in the feed direction of the fabric layers to be sewn, wherein a presser foot length in the feed direction is greater than 20 mm, greater than 40 mm, or greater than 60 mm. Such a long presser foot additionally prevents the fabric layers to be sewn from rolling up and ensures that the fabric layers are flat and wrinkle-free for sewing on the sewing machine and glide into the sewing area of ​​the sewing machine. The presser foot smooths the fabric layers during sewing. At the same time, the presser foot exerts pressure on the underlying fabric layers. The fabric layers are fixed between the presser foot and a lower part of the sewing machine, e.g. a feed element for the fabric layers, lifted and transported stitch by stitch.In addition, a vacuum area can be provided on the work table in front of the sewing machine's presser foot in the conveying direction in order to smooth the layers of fabric in front of the sewing machine.

[0028] In particular, the sewing area on which the fabric layers rest during sewing has a smoother surface of the work table than a rougher surface of the work table in an area in which the first fabric layer is positioned on the second fabric layer.

[0029] According to a further exemplary embodiment, the handling mechanism moves the stack of fabric layers over the adhesive regions in such a way that the position of the lower second fabric layer is adjusted to the first upper fabric layer due to the static friction to the adhesive region.

[0030] In an exemplary embodiment, the roughness of a surface of the work table can be adjusted, for example, by providing retractable and extendable bristles. The bristles can extend at a right angle to the surface of the work table. Additionally or alternatively, bristles can have an angle of less than 90° to the surface of the work table. Thus, different friction can be set depending on the direction of movement of the material layers over the bristles. In an exemplary embodiment, a control unit can control the extension of the bristles. Furthermore, in a further exemplary embodiment, the angle of the bristles can be adjusted in order to adjust the friction and in particular the direction of friction with regard to the material layers over the bristles.For example, angled holes can be drilled or punched into the surface of the work table to accommodate correspondingly angled bristles (alternatively, angled tips or microneedles can be used). Alternatively, the bristles can be glued onto a surface or corresponding bristles can be manufactured from plastic using an injection molding process. Very fine structures can be created by brushing, grinding, engraving, or etching the surface. Moving or milling layers of fabric over such a surface leads to a preferential movement in one of the coordinate directions along the work table (X, Y), which can be used to tension or smooth layers of fabric and / or to reduce wrinkling. This effect can also be achieved with other coloring techniques.For example, a shirring device with elastic and / or movable slats can be used on the surface of the work table, but these are made of softer materials and the fabric layer is not moved 'against the grain', but only with light pressure of the fabric layer on the shirring device leads to a smoothing of the fabric.

[0031] According to a further exemplary embodiment, the handling mechanism moves the stack of fabric layers with a first feed relative to the sewing machine during sewing, wherein the sewing machine moves the stack of fabric layers with a second feed. In particular, the handling mechanism controls the first feed differently than the second feed of the sewing machine. It has proven advantageous to control the feed of the effector or the handling mechanism (which guides the fabric layers) differently than the feed of the sewing machine, particularly during the sewing process. For example, this can be used to set a certain tension for the sewing between the first and second fabric layers, or to support the formation of ruffles (i.e., one fabric layer forms loops on the other fabric layer, which remains wrinkle-free and taut, or one fabric layer is stretched or extended relative to the other).In addition, path and movement differences between the handling robot and the sewing machine can be adjusted, especially with a time delay.

[0032] According to another exemplary embodiment, after the sewing step, the method comprises gripping a third fabric layer with the handling mechanism. Furthermore, the third fabric layer is positioned over the sewn first and second fabric layers, which rest on a work table. The third fabric layer is secured to the sewn first and second fabric layers to form a fabric layer stack using the securing mechanism, such that a further joining region of the third fabric layer rests on a further joining region of the first and / or second fabric layer.

[0033] This stack of fabric layers is then fed to the sewing machine using the handling mechanism, and the remaining joining areas are sewn together. During the sewing process, the handling mechanism guides the stack of fabric layers relative to the sewing machine. This allows three layers to be sewn together, e.g., when sewing a label into a hem. For example, a label is first sewn onto a second layer of fabric as the first layer of fabric, then the third layer is placed, and the sewing step is repeated. This allows for more precise label placement and reduces slippage problems when securing three layers of fabric.

[0034] According to a further exemplary embodiment, the fixing mechanism fixes the first and second fabric layers along at least one (continuously extending) fixing region and / or along several spaced-apart fixing regions. According to a further exemplary embodiment, the fixing regions have an area of ​​less than 1 cm 2 , especially less than 20 mm 2 , especially less than 8 mm 2 Additionally or alternatively, the fixation areas are spaced apart by more than 2 cm, particularly more than 3 cm or more than 4 cm. Thus, good fixation between two layers of fabric can be achieved without having to create a continuous, temporary fixation path with the fixation mechanism.

[0035] According to a further exemplary embodiment, at least one of the fixing regions is severed during or after sewing, wherein the fixing region is severed in particular at a cutting speed that is coordinated with and substantially coincides with the feed rate during sewing with the sewing machine. The fixing regions are at least partially removed again, as they may lead to hardening / stiffening of the fabric layers. For example, this fixing can occur in an area that is cut off again during or after the sewing process. To ensure that the fixing lasts as long as possible, this cutting can also be done incrementally depending on the sewing progress.

[0036] According to an exemplary embodiment, the work surface of the work table is movably mounted and moved, wherein in particular the movement of the work surface occurs synchronously or in coordination with the movement of the effector. The movement of the work surface occurs in particular during sewing, wherein the work table in particular has a conveyor belt as a work surface for conveying at least one layer of fabric placed thereon relative to the sewing machine. In an exemplary embodiment, in particular the movement of the work surface, the handling mechanism and the feed of the sewing machine are synchronized (in particular by means of the control unit). Thus, more precise control during sewing and corresponding sewing quality (in particular when the two layers of fabric are only weakly fixed) can be achieved by transporting the work surface from below and the handling mechanism from above.The work surface can be mounted movably on the work table, or the entire work table can be moved. This can be achieved, for example, by the work surface consisting of a conveyor belt. The two layers of fabric are precisely positioned and stacked on this and then pressed down with the effector. If this is implemented with the overhang relevant to the invention outside the effector contour, the conveyor belt can move past the sewing machine and at the same time the effector can support the movement synchronously from above. This can reduce the effort required for more complex fixings while still ensuring that the two layers of fabric do not slip. The work surface can also be equipped with increased friction resistance (e.g. 'no slip' surface). This design variant is advantageous if the fabric being processed has a highly adhesive surface or decoration (e.g. rubber trim).Without this displacement support, there is a risk that the adhesion to the sliding surface during the sewing process is stronger than the fixation, which can lead to distortion or poor seam quality.

[0037] According to a further exemplary embodiment, the handling mechanism has an effector contour, wherein one of the fabric layers or the fabric layer stack can be fastened within the effector contour. The effector contour is smaller than an outer contour of the fabric layer or the fabric layer stack. The handling mechanism is designed such that the joining regions of the fabric layers form a projection of more than 0.5 cm, in particular more than 1 cm, further in particular more than 2 cm or more than 3 cm, relative to the effector contour. The effector contour describes the region on a fabric layer at which the fixing mechanism and / or the handling mechanism exerts a fixing force or holding force. The effector contour is defined, for example, by the border of the fixing surface or by the connecting lines between the individual fixing points at which there is holding contact with a held fabric layer within the xy plane.The connecting lines form an effector contour within the fabric layer. In the inner holding area, the fabric layer can be tensioned, thus defining the xy plane. At the outer edge areas of the fabric layers, which lie outside the effector contour defined by the fixation points, the joining areas are formed, and the fabric layer can be left untensioned there, effectively protruding from the xy plane.

[0038] The resulting fabric overhang facilitates subsequent sewing, as the sewing machine can more easily reach the joining areas. This overhang can then be placed on at least one other free area of ​​fabric or the joining area of ​​the next layer of fabric. Alternatively, the overhang can be manipulated so that it is folded (e.g., for a hem), thus forming the first and second layers from one piece of fabric.

[0039] According to a further exemplary embodiment, the handling mechanism, with a holding needle device, inserts holding needles with a predetermined penetration depth and / or a predetermined penetration angle into the first fabric layer or the fabric layer stack for attachment to the effector. The predetermined penetration depth and / or the predetermined penetration angle can be determined in particular in real time and / or based on sensor feedback. The holding needles can in particular have a diameter of less than 1300 micrometers, less than 900 micrometers, in particular less than 550 micrometers, and further in particular less than 250 micrometers. For example, a holding needle can be inserted into the fabric piece at a shallow angle or not as deeply during transport, while after positioning on another fabric piece, a steeper angle or a greater penetration depth is used to fix both parts.

[0040] By means of the holding needle device, one or more needle-like pins or holding needles can be driven from a magazine into or through the fabric layers, either from the effector side, from the work table side, or from an auxiliary system (e.g., auxiliary plate, needle belt), in order to fasten them together. The holding needle device has, in particular, a feed device, for example, a holding needle magazine, which is configured to feed holding needles for the holding needle device.

[0041] According to a further exemplary embodiment, at least one of the fabric layers is fixed to the work surface by means of a hold-down device on the work table. The hold-down device is configured to selectively fix at least one of the fabric layers to the work table, in particular by means of pneumatic, mechanical, magnetic and / or electrostatic holding forces. The hold-down device can press against the work table / work surface with a force, which leads to a fixation of the two intermediate fabric layers. Alternatively, the effector can also

[0042] Allow compressed air to flow between its underside and the fabric layers. This is particularly helpful when the effector needs to reposition itself so that it can quickly overcome the adhesive forces between the effector and the first fabric layer.

[0043] The holding device is particularly designed to hold the fabric layers in place until the holding mechanism takes over. Furthermore, a ferromagnetic support plate can be placed on the work table, for example, onto which a piece of fabric is placed. After folding over a layer of this piece of fabric or after placing another layer of fabric, the effector can attract the support plate using a magnet (in particular an electromagnet), thus holding the layers of fabric between them. Alternatively, an electrostatic holding mechanism can be used on both the work table and the effector side. This is particularly helpful for the precise placement of two layers of fabric on top of one another. After placement, the effector can then reinforce the hold in such a way that two layers of fabric are held securely, and a holding-down device built into the table can be deactivated.

[0044] The work surface is in particular embedded in the work table and the work surface is in particular designed as a work plate with a thickness of less than 1 mm, in particular less than 5 mm or less than 3 mm, wherein the stack of fabric layers is in particular placed on the work surface in such a way that the stack of fabric layers forms an overhang to at least part of the work surface.

[0045] The work surface can either be a permanently mounted work table or a movable auxiliary plate (work surface) which can be moved in at least one coordinate direction. Alternatively, this auxiliary plate can also be temporarily connected to the effector and thus move simultaneously with the effector. In particular, the work surface can be partially integrated into the work table and form a surface without significant height differences in at least one direction (and be movable in another direction, for example). The work surface can also be designed to be relatively thin (in the z-direction, i.e. technically speaking, 'of a small height'). It is particularly advantageous if the fabric stack forms an overhang on at least part of the work surface, so that the fabric stack including the work surface can be guided directly past the sewing system.According to a further exemplary embodiment, fabric layer data relating in particular to fabric layer material and / or fabric layer geometry is determined. Additionally or alternatively, processing data, in particular the left / right position, alignment, folds and / or manufacturing quality of one of the fabric layers or the fabric layer stack, is determined. Additionally or alternatively, positioning, placement, and fixation during sewing and / or the sewing quality is determined. The collected data is evaluated to determine the quality of the sewn fabric layers. In particular, the data can be collected in a data processing unit. A control unit coupled to the data processing unit can analyze the corresponding data and initiate appropriate control of the sewing machine or handling robot. In this way, a change in reliability can be detected and communicated to a higher-level system.This can be used, for example, to initiate preventive maintenance or adjust handling parameters. The system can also receive information from the sewing machine for this purpose.

[0046] According to a further exemplary embodiment, the fixing step comprises supplying an adhesive for temporarily bonding the first fabric layer and the second fabric layer together (in particular by means of the fixing mechanism). The adhesive can, in particular, contain a water-soluble polymer, in particular polyethylene glycol and / or polyvinyl alcohol, sodium thiosulfate pentahydrate, sodium acetate trihydrate, ammonium alum dodecahydrate, urea, and / or eutectic salt mixtures.

[0047] An adhesive device as a fixing mechanism for temporarily securing the fabric layers can, for example, comprise an adhesive that can be thermally activated (hot melt principle) and then washed out during the first wash cycle. Water-soluble polymers with a relatively moderate melting point are used for this purpose, such as PEG (polyethylene glycol). For example, a water-soluble polymer with an elevated melting temperature of around 200 degrees Celsius can form PVOH (polyvinyl alcohol) with a suitable degree of hydrolysis. Furthermore, low-melting salts such as sodium thiosulfate pentahydrate (melting point or glass transition temperature FP 45-50 degrees Celsius) or sodium acetate trihydrate (melting point FP e.g. 60 degrees Celsius) or ammonium aundodecahydrate (melting point FP e.g. 120 degrees Celsius) are suitable. In these cases, a phase transition occurs during cooling and bonding, which is greatly favored by the fine fabric / fiber structure.These products are also relatively unproblematic in terms of toxicity and disposal / washing water.

[0048] The adhesive can in particular comprise a pressure-activated adhesive, a hot melt adhesive and / or a two-component adhesive, in particular such that the adhesive is removable again during and / or after a further processing step, in particular can be separated together with a material part of the first fabric layer, the second fabric layer and / or the fabric layer stack. In a further exemplary embodiment, a fast-reacting (e.g. pressure-activated) adhesive is used, in particular for temporary fixing. One of the possible implementations is an encapsulated superglue, characterized in such a way that the capsule breaks open under pressure. The capsule is made, for example, of a rigid, brittle material such as glass and is very small (capsule diameter in the micrometer range). The presentation can be either as a powder of beads or further incorporated into adhesive dots or adhesive tapes.Processing can be dry or in a conveying fluid (which supplements the superglue or, alternatively, is the second phase of a fast-curing two-component adhesive [the first phase is within the capsules]). Pressure (from the effector or an additional device mounted on the table) activates the adhesive, quickly bonding the two layers of fabric, thus achieving the desired fixation. If this occurs in a section after subsequent joining, the contamination, the "impossibility of removal," and the rigidity of this process are not detrimental. Alternatively, this can also be achieved with hot-melt glue.

[0049] Furthermore, PVOH adhesives with a low water content, i.e., liquid to low-melting, can be used as adhesives. A urea melt with a melting point (FP) of, for example, 133 degrees Celsius can also be used. Eutectic salt mixtures or substance mixtures can also be used as adhesives.

[0050] Good adhesive properties have been achieved, particularly with water-soluble polymers. For example, with Kollisolv PEG 3350 from BASF, which melts at just 50 degrees Celsius and is easily soluble in water.

[0051] Notably, the adhesives described above are also non-toxic and approved for medical applications, which eliminates any potential for human contact with clothing prior to washing. Additionally, the bonding can be applied to an area of ​​the fabric layers that will be separated during subsequent processing.

[0052] According to a further exemplary embodiment, a seam end is detected during sewing (for example by means of optical sensors), wherein during sewing at the seam end the feed of the handling device and / or the sewing machine is changed at the seam end in order to vary the tension of the fabric layers between the sewing machine and the effector in strength and / or direction. This ensures that, for example, a special action can be carried out at the seam end, such as a final knot, a sealing of the seam end, or a specific seam length so that the thread can be cut at the end. According to a further exemplary embodiment, after sewing, a thread with a predetermined thread length is cut after one end of the seam, wherein the handling mechanism moves the stack of fabric layers relative to a thread cutting device in such a way that the thread length is adjustable.For example, at the end of a seam, after the last stitch has been sewn, a quick movement of the handling mechanism away from the sewing machine can create an extended thread section. In other words, a sliding movement to reposition the fabric layers can be provided using the handling mechanism or effector, which either guides the thread to a thread cutter (or vice versa), or it can simply be a retraction of the free thread through the sewing system, so that a defined thread length is achieved at the end of the seam.

[0053] According to a further exemplary embodiment, a heating device for heating the fabric layers and / or a moistening device for moistening the fabric layers is arranged on the work table in order to smooth, in particular iron, at least one of the fabric layers and / or the stack of fabric layers. Additionally or alternatively, to carry out the smoothing action, the effector can have a smoothing plate, in particular a heatable smoothing plate, and can be configured such that smoothing can be performed by pressing the smoothing plate onto the fabric layer.

[0054] According to a further exemplary embodiment, a further sewing device is arranged on the work table, so that during or after the sewing of the joining areas, the further sewing device sews further joining areas of the first and second fabric layers. The sewing device and the further sewing device form, in particular, different types of seams, in particular an overlock seam and a coverstitch seam, in the joining areas. It is efficient if the handling robot performs more than one activity based on position knowledge or operates several sewing devices using a held stack of fabric layers. For this reason, it is advantageous if more than one sewing system is available within the working area of ​​the handling robot.On the one hand, this allows different tasks (sewing two fabrics together and re-stitching a hem) to be performed without requiring long interruptions due to re-stitching the fabric layers. On the other hand, it also allows a thread breakage on one machine to be compensated for by using an alternative machine. It can be particularly advantageous if these sewing systems are different, as this allows different tasks to be performed without having to change the end effector. For example, if one sewing system can perform overlock seams (possibly with excess trimming) and the other sewing system can perform coverstitch seams.

[0055] According to a further aspect, a program element for robot-assisted sewing of fabric layers for clothing is provided, which, when executed by a processor, is configured to perform the method described above. The program element can be used to provide instructions for controlling a computer system to coordinate the execution of the method described above.

[0056] The computer program may be implemented as computer-readable instruction code in any suitable programming language, such as JAVA, C++, and stored on a computer-readable medium (removable disk, volatile or non-volatile memory, embedded memory / processor, etc.). The instruction code can be used to program a computer or other programmable device to perform the intended functions. The computer program may be made available via a network, such as the World Wide Web, from which it can be downloaded. The invention may be implemented using a computer program or software. However, the invention may also be implemented using one or more specific electronic circuits or hardware. Furthermore, the invention may also be implemented in a hybrid form, i.e., in a combination of software and hardware modules.

[0057] According to a further exemplary embodiment of the system, the handling mechanism is selected from the group consisting of grippers, suction cups, clamps, areas with increased friction and / or electrostatic attraction, rollers, freezing grippers, and / or Bernoulli grippers.

[0058] Electroadhesive grippers for electrostatic attraction work with electrostatic fields. Holding forces are generated through polarization. They can be generated on the upper side of the fabric layer, which is in contact with a gripper dielectric of the electroadhesive gripper.

[0059] A Bernoulli gripper has a suction body, with compressed air flowing outward along the xy plane between the fabric part and the suction body via a flow channel at the edges of the suction body. An air opening is located in the center of the suction body, which is coupled to the flow channel. Due to the Bernoulli effect, air is sucked into the flow channel from the direction of the fabric part. This creates a fixation force between the fabric part and the suction body.

[0060] A freezing gripper has a highly chilled contact surface with the fabric part, whereby frozen water or ice acts as an adhesive to adhere the fabric part to the contact surface. The water can be obtained as an adhesive from the atmosphere (air humidity) or added from an adhesive supply. According to a further exemplary embodiment, the handling mechanism has holding needles that penetrate at least into the first fabric layer, the second fabric layer, and / or the fabric layer stack in order to attach them to the effector. Furthermore, a penetration depth and / or a penetration angle of at least one holding needle can be controllable, in particular in real time and / or based on sensor feedback. An additional form of differentiated gripping with the handling mechanism can relate to the depth of a holding needle and / or the angle of a holding needle (and in particular a plurality thereof).For example, a holding pin can be inserted at a shallow angle or not as deeply into the fabric layer when separating, whereas when tacking two layers of fabric (for joining) a steeper angle or a greater penetration depth can be used to securely grasp both layers of fabric.

[0061] According to a further exemplary embodiment, the holding needles have a diameter of less than 1300 micrometers, less than 900 micrometers, in particular less than 550 micrometers, and more particularly less than 250 micrometers. It has been found that, when fine microneedles are used as holding needles in combination with a suitable vacuum and a suitable air flow, no quality-impairing effects remain on the fabric surface after processing. This has been demonstrated particularly with needle diameters of less than 1300 micrometers, less than 900 micrometers, in particular less than 550 micrometers, and preferably less than 250 micrometers.

[0062] According to a further exemplary embodiment, holding needles are arranged on a control surface of the handling mechanism, wherein a surface shape of the control surface is adjustable such that in a first embodiment of the surface shape the holding needles are oriented parallel to one another in order to penetrate into or extend into at least one layer of material, and in a second embodiment of the surface shape the holding needles are not aligned parallel to one another in order to fix them in at least one layer of material.

[0063] When the control surface bends, the holding pins spread and secure the two fabric layers. When the control surface bends back, for example, with a smooth movement or abruptly by clicking back, the holding pins, which are usually aligned parallel to each other again, detach from the fabric layers. Using such a handling mechanism, the fixation on the handling mechanism can be gradually removed as the sewing progresses, particularly when two layers of fabric are stacked.

[0064] According to another exemplary embodiment, the surface shape of the control surface is deformable and, in particular, prestressable by means of mechanical or hydraulic elements. Furthermore, the control surface can be elastically deformable, so that it can be prestressed and automatically deformed back into an initial position without an external restoring force, for example, by the retaining pins running parallel or by the retaining pins being at an angle to one another. The control surface can continuously move back to an initial position. Furthermore, the control surface can, for example, comprise a material with a memory effect and can snap or spring back into an initial position.

[0065] According to another exemplary embodiment, the effector has a contact surface within an effector contour, against which one of the fabric layers or the stack of fabric layers can be placed. The contact surface forms, in particular, part of the handling mechanism for securing one of the fabric layers or the stack of fabric layers, wherein the contact surface is configured to hold one of the fabric layers or the stack of fabric layers to the effector magnetically, using air pressure, mechanically, or electrostatically.

[0066] The contact surface allows the fabric layers or stacks of fabric layers to be transported and stored without distortion or wrinkles, and later. After positioning or stacking the fabric layers, the contact surface makes it easier to secure the fabric layers. The contact surface can, for example, be part of the magnetic device and be designed accordingly. Furthermore, the contact surface can hold the fabric layers using vacuum, mechanical elements (e.g., continuous microneedles), or electrostatic elements.

[0067] According to a further exemplary embodiment, the contact surface, as part of the handling mechanism, forms a suction surface against which one of the fabric layers or the fabric layer stack can be placed. The suction surface has a plurality of suction openings, in particular more than 9, more than 15, more than 22 and / or more than 30 suction openings, wherein the suction openings are in particular designed with a diameter of less than 20 mm, in particular less than 10 mm, furthermore in particular less than 5 mm, furthermore in particular less than 3 mm. With a handling mechanism based on negative pressure, with a small suction opening, sufficient force can only be generated with a high degree of negative pressure to hold the fabric layers. The fabric layer deforms, which could in particular make ironing necessary in a subsequent work step. On the other hand, large suction openings, even with little negative pressure, deform the textile material to such an extent that it no longer lies sufficiently flat in the xy plane.In addition, when positioning on another layer of material, this can also be sucked in, which counteracts precise positioning. For this reason, a solution was chosen which uses a large number of small suction openings (distributed over a larger area or edge). Tests with smaller diameters of these suction openings have shown that the layers of material are held flat in the xy plane. This in particular prevents warping and the formation of wrinkles during later laying down. According to a further exemplary embodiment, a vacuum on the suction surface for holding the layers of material or the stack of layers of material can be adjusted in such a way that the vacuum can be varied by more than 15%, in particular more than 30% or more than 45%. In the exemplary embodiment in which the handling mechanism is implemented by means of a suction device, a gripping function is achieved by means of negative pressure. The suction device has a suction cup orA suction cup, to which a vacuum pump or suction pump is connected, is used to extract air from the suction cup. This creates a negative pressure in the space between the fabric part and the suction cup, which generates a holding force. The negative pressure can be measured using sensors, for example, to adjust the suction power accordingly using the control device.

[0068] The suction power or vacuum can be adjusted for different fabric types. Good results were achieved with the following vacuum levels: The control unit and the vacuum pump should be configured in such a way that the vacuum can vary by more than 15%, especially more than 30%, and preferably more than 45%. This allows for a high degree of adaptability to different fabrics. Furthermore, the sources of error such as incorrect fixation, suction to the work table, and slipping during sewing can be significantly reduced.

[0069] According to a further exemplary embodiment, the fixing mechanism comprises a welding device, in particular an ultrasonic welding device, for, in particular temporarily, welding the first and second fabric layers together, wherein the fixing mechanism comprises in particular a feed device for feeding welding material. Depending on the material properties, a plastic welding technique, in particular ultrasonic welding, can be used. A suitable auxiliary material (ultrasonic welding tape, hot melt adhesive, etc.) can also be inserted beforehand (or during the welding process) using the feed device. Alternatively, an adhesive can be placed beforehand using a dosing device. For example, the effector can move to a stack of fabric layers.The feed device can, for example, feed a solid welding material, such as a welding wire, or a viscous fluid that solidifies under the influence of heat, particularly at the superimposed joining areas of the fabric layers in the fabric stack. The feed device can be attached, for example, to the work table or the effector. The fixation mechanism accordingly has a heat-generating welding element, which heats the welding material in the joining area of ​​the fabric layers, thus creating a weld seam.

[0070] According to a further exemplary embodiment, the

[0071] Fixing mechanism has a suction device with at least one suction device, wherein the suction device is designed to suck air from the first and second material layers by means of the suction device in such a way that the superimposed first and second material layers can be fixed to the suction device.

[0072] According to a further exemplary embodiment, the fixing mechanism comprises a magnetic device configured to attract a magnetic element toward the effector such that the fabric layers that can be arranged between the effector and the magnetic element can be fixed. Since the fabric layers are permeable to air to a certain extent due to their material properties, two or more fabric layers in a fabric layer stack can be fixed by suction with an appropriately adjusted suction power. The suction device comprises, for example, a vacuum pump that can be arranged at a distance from the effector, for example on the work table. One or more suction devices, such as suction cups, can be attached to the effector as part of the fixing mechanism. Furthermore, the suction device with the suction devices can also form parts of the handling mechanism for aligning and conveying the fixed fabric layers.In an exemplary embodiment, the suction device also forms part of the handling mechanism for handling the layers of fabric.

[0073] According to a further exemplary embodiment, the fixing mechanism comprises a clamping device which is configured to clamp the first fabric layer and the second fabric layer together.

[0074] According to another exemplary embodiment, the fixing mechanism comprises an adhesive device configured to temporarily bond the first fabric layer and the second fabric layer together. Furthermore, the adhesive device may comprise a heating element, such as a heated bar or a hot-air gun, to enable, for example, hot bonding. In particular, various adhesive materials, such as instant adhesives, contact adhesives, pressure-activated adhesives, or welding adhesives (e.g., for PVC materials), may be used.

[0075] The adhesives are designed in such a way that an adhesive force is generated that enables the fabric layers to be separated later. Furthermore, an adhesive can be designed to lose its adhesive effect under the influence of temperature or under the influence of certain radiation (for example, UV radiation), so that the fabric layers can be separated again after a joining step. Accordingly, the bonding device can, for example, have a temperature control device or a radiation device designed to release the adhesive bond. The temperature control device or the radiation device can, for example, be arranged on the work table. The bonding device furthermore has, in particular, a feed device that is configured to provide a temporary bonding of the first fabric layer and the second fabric layer by adding an adhesive.

[0076] According to a further exemplary embodiment, the fixation mechanism comprises a holding needle device configured to introduce holding needles into the first fabric layer and the second fabric layer for fixation. By means of the holding needle device, one or more needle-like pins or holding needles can be driven from a magazine into or through the fabric layers, either from the effector side, from the work table side, or from an auxiliary system (e.g., auxiliary plate, needle belt), in order to fasten them together. The holding needle device comprises, in particular, a feed device, for example, a holding needle magazine, configured to feed holding needles for the holding needle device.

[0077] According to an exemplary embodiment, the fixing mechanism comprises a stapling device which is configured to introduce at least one staple into the first fabric layer and the second fabric layer for fixing, wherein the stapling device in particular comprises a feeding device which is configured to feed staples for the stapling device,

[0078] According to another exemplary embodiment, the fixation mechanism comprises a hold-down device configured to apply a contact force to the first fabric layer and the second fabric layer toward the work surface. The hold-down device can press against the work table / work surface with a force, resulting in the fixation of the two intermediate fabric layers. Alternatively, the effector can also allow compressed air to flow between its underside and the fabric layers. This is particularly helpful when the effector needs to reposition itself so that it can quickly overcome the adhesive forces between the effector and the first fabric layer.

[0079] According to a further exemplary embodiment, the handling mechanism has a support element, in particular a support plate, for placing the stack of fabric layers to be conveyed, wherein the handling mechanism is in particular configured such that the first fabric layer and second fabric layer fixed by the fixing mechanism can be lifted together and the support element can be conveyed under the fixed first fabric layer and second fabric layer. The support element can, for example, be fork-shaped, or the support plate can have a round support surface or a square support surface. Furthermore, the support element can have an adhesive surface so that the fabric layers do not accidentally slip off during transport or joining. The support element can, for example, be arranged in an articulated manner on the effector (e.g. via a further robot arm) in order to be inserted accordingly under or between the fabric layers.In other words, the topmost layer(s) of fabric from a stack of fabric layers can be lifted. To do this, the handling mechanism can lift the topmost layer of fabric or at least one edge or border using the embodiments explained (e.g. using a temporary adhesive, holding or microneedles, a Bernoulli gripper, suction cups or a vacuum), so that the support element can be moved in between, i.e. can then be transported between the topmost layer(s) of fabric and the layers of fabric underneath or to the work table. In other words, the support element first moves in the x- or y-direction underneath the layer of fabric to be lifted, so that at the beginning the front edge of the support element is parallel to the straight cut edge of the layer of fabric. When the support element has been pushed underneath completely (or at least), the support element is moved vertically or horizontally together with the layer of fabric to be lifted.lifted in the z-direction and thus separated from the rest of the underlying layers of material.

[0080] In summary, the following process sequence can be carried out using the method according to the invention:

[0081] A) Gripping and positioning a layer of fabric using the handling mechanism of a handling robot

[0082] B) Fixing two layers of material on top of each other by means of the fixing mechanism, wherein the action of the effector for fixing by means of the fixing mechanism differs from the action for gripping (step A) by means of the handling mechanism and the fixing by means of the fixing mechanism is carried out by means of at least one action from the list: welding, suction, folding, magnetic fixing, clamping, gluing, stapling, holding down, pressing together, piercing and / or piercing.

[0083] C) Feeding the two layers of fabric to a sewing machine, whereby the areas to be sewn, ie the joining area, of the fabric layers form an overhang, D) Sewing these layers of fabric with the support of a continuous guidance of the handling mechanism

[0084] E) The sewn parts are removed from the sewing machine by the handling mechanism.

[0085] The intended overhang of multi-layered fabric is a prerequisite for subsequent automated sewing. For this purpose, the already flat and horizontally positioned fabric stack is fed to a sewing machine (controlled by the automation system) by the handling robot and sewn. The handling robot guides the fabric stack in coordination with the feed (i.e., the forward and backward transport via the presser feet) of the sewing machine. The sewing machine can have both a top feed dog and / or a bottom feed dog (fabric transport through the needle plate). The sewing machine can also be equipped without a feed dog. In another exemplary embodiment, the presser foot described above can be used as the feed dog. A triple feed system can also be used, in which the needle is moved in addition to the top and bottom feed dogs (especially with stiff fabrics).By securing the fabric layers and carrying the robot (which takes on the fabric weight for heavy fabrics), clean transport and thus good seam quality can be achieved. This eliminates the need for additional transport aids such as sewing in paper, powder, oil, etc. In particular, this allows a garment to be produced without subsequent washing and ironing.

[0086] However, guidance by the robot can also allow different feeds of the upper and lower fabric if the fabric layers are not fixed to one another, but rather the fixation focuses on separately guideable auxiliary structures (e.g. thin plates). For example, a holding / conveying device can be built into the work table (e.g. with electrostatic holding or electrostatic transport [similar to a linear motor]), which transports the lower fabric layer and the robot arm with the effector fixes the upper fabric layer. This allows different travel paths for the upper and lower fabric during sewing, which allows certain 3D effects after the sewing process. Sewing machines exist that allow this different transport of upper and lower fabric. With the solution according to the invention, however, correspondingly automated production can be achieved.The insertion of the two layers of fabric into the different transport devices of the sewing machine can be achieved by separate movements of the different feeds (as explained at the beginning of this section), but it can also be achieved by different widths of an overhang of a tacked double layer (and the tack is then released during the sewing process, e.g. cut off).

[0087] It should be noted that the embodiments described here represent only a limited selection of possible embodiments of the invention. It is thus possible to combine the features of individual embodiments in a suitable manner, so that a multitude of different embodiments can be regarded as obviously disclosed by the embodiments explicitly described here. In particular, some embodiments of the invention are described with device claims, and other embodiments of the invention with method claims. However, upon reading this application, it will immediately become clear to the person skilled in the art that, unless explicitly stated otherwise, in addition to a combination of features belonging to one type of subject matter of the invention, any combination of features belonging to different types of subject matter of the invention is also possible. Brief Description of the Drawings

[0088] For further explanation and better understanding of the present invention, exemplary embodiments are described in more detail below with reference to the accompanying drawings. They show:

[0089] Fig. 1 to Fig. 4 show schematic representations of a method for handling and processing fabric layers according to an exemplary embodiment according to an exemplary embodiment.

[0090] Fig. 5 shows a schematic representation of a handling mechanism that holds a stack of fabric layers within an effector contour.

[0091] Fig. 6 shows a schematic representation of a magnetic device as a fixing mechanism according to an exemplary embodiment.

[0092] Fig. 7 shows a schematic representation of an effector with a contact surface according to an exemplary embodiment.

[0093] Fig. 8 shows a schematic representation of an effector with a handling mechanism and a fixation mechanism according to an exemplary embodiment.

[0094] Fig. 9 shows a schematic representation of a work table with adjustable static friction on the work surface according to an exemplary embodiment.

[0095] Fig. 10 shows a schematic representation of a handling mechanism with a gripping device according to an exemplary embodiment of the present invention. Fig. 11 shows a schematic representation of a handling mechanism with a suction device according to an exemplary embodiment of the present invention.

[0096] Fig. 12 shows a schematic representation of a handling mechanism with an electrostatically charged element according to an exemplary embodiment of the present invention.

[0097] Fig. 13 shows a schematic representation of a handling mechanism with holding needles according to an exemplary embodiment of the present invention.

[0098] Fig. 14 shows a schematic representation of an effector with several different handling mechanisms, for example with a suction cup and holding needles according to an exemplary embodiment of the present invention.

[0099] Fig. 15 shows a schematic representation of a handling mechanism with a gripper that grips an upper side of a fabric layer, according to an exemplary embodiment of the present invention.

[0100] Fig. 16 shows a schematic representation of a handling mechanism with a suction surface according to an exemplary embodiment of the present invention.

[0101] Fig. 17 to Fig. 19 show schematic representations of a fixation mechanism with a folding device according to an exemplary embodiment of the present invention. Fig. 20 shows a schematic representation of the folding device arranged on a work table according to an exemplary embodiment of the present invention.

[0102] Fig. 21 shows a schematic representation of fabric layers with an overhang outside an effector contour, according to an exemplary embodiment.

[0103] Fig. 22 to Fig. 24 show schematic representations of a handling mechanism with holding needles according to an exemplary embodiment.

[0104] Fig. 25 shows a schematic representation of a positioning of a third fabric layer on two already sewn fabric layers according to another exemplary embodiment.

[0105] Detailed by exem

[0106] Identical or similar components in different figures are provided with the same reference numerals. The representations in the figures are schematic.

[0107] Fig. 1 to Fig. 4 show schematic representations of a method for robot-assisted sewing of fabric layers 111, 112 for clothing. The method comprises gripping a first fabric layer 111 or a second fabric layer 112 with a handling mechanism 120 of a handling robot 100 having an effector 101 for handling fabric layers 111, 112 (see Fig. 1). The first fabric layer 111 is positioned over a second fabric layer 112, which rests on a work table 103 (see Fig. 2), and the first fabric layer 111 is fixed to the second fabric layer 112 to form a fabric layer stack 113 by means of a fixing mechanism 130, which is arranged at least partially on the effector 101, such that a joining region 114 of the first fabric layer 111 rests on a further joining region 115 of the second fabric layer 112 (see Fig. 3).Furthermore, the fabric layer stack 113 is fed to a sewing machine 140 by means of the handling mechanism 120, with the joining areas being freely accessible to the sewing machine 140. The joining areas are sewn, with the handling mechanism 120 guiding the fabric layer stack 113 relative to the sewing machine 140 during the sewing process (see Fig. 4). The sewn fabric layer stack 113 is fed from the sewing machine 140 to a storage location by means of the handling mechanism 120.

[0108] The handling robot 100 has the effector 101, to which the corresponding handling mechanism 120 is attached, in particular in an interchangeable manner. The handling robot 100 is attached to the floor by a stationary robot base in order to introduce corresponding forces into the floor. A robot arm 104 is arranged between the effector 101 and the robot base. This robot arm has, for example, one or more joints in order to control the effector 101 into a desired position. In particular, the handling robot 100 is designed to handle or manipulate the fabric layers 111, 112 and to move and position them accordingly.

[0109] The handling robot 100, as well as the corresponding handling mechanism 120, the fixing mechanism 130 and / or the sewing machine 140 (or another joining unit) are coupled by means of a control unit 105, so that a fully automatic positioning of the fabric layers 111, 112 and a subsequent joining can be carried out.

[0110] The controllable handling mechanism 120 and the fixing mechanism 130 are arranged on the effector 101. The fixing mechanism 130 is designed to fasten at least two fabric layers 111, 112, which in particular lie one on top of the other, so that the fixed two fabric layers 111, 112 can be conveyed in particular as a package or as a stack of fabric layers 113.

[0111] In particular, the handling mechanism 120 can transport a fabric layer 111 or the described fabric layers 111, 112 fixed together, for example, to the sewing machine 140 or another sewing machine. The effector or the handling mechanism 120 can adapt to the contour of the fabric layers 111, 112, for example, by adjusting the fixing points of the handling mechanism 120 to which the fabric layers 111, 112 are fixed. For example, the fixing elements 901 shown in Fig. 9, in which the individual fixing points are formed, can be arranged for this purpose.

[0112] In one exemplary embodiment, the fixation mechanism 130 is arranged entirely on the effector 101. However, for example, part of the fixation mechanism 130 can also be arranged on a work table 103, on which, for example, the fabric layers 111, 112 are placed.

[0113] Accordingly, the handling mechanism 120 is completely attached to the effector 101, but a part of the handling mechanism 120 can also be attached to the work table 103.

[0114] The effector 101 thus forms an end part of the handling robot 100 with, for example, a suction device as handling mechanism 120, which grasps and manipulates a fabric layer 111, 112 or a fabric layer stack 113 consisting of fabric layers 111, 112 that are fastened with the fixing mechanism 130.

[0115] The sewing machine 140 is configured to process the joining areas of a fabric layer 111, 112 and / or to connect at least two fabric layers 111, 112. The sewing machine 140 can be a sewing machine, a welding machine, a tacking machine, a crocheting machine, an automatic gluing machine, or other automatic joining machines for fabric layers 111, 112.

[0116] Fig. 1 shows the handling robot 100, which places a fabric layer 112 on a work surface 102 of the work table 103 using a suction device as the handling mechanism 120. The work surface 102 is aligned in a horizontal x, y plane. The effector 101 can be moved, for example, along the horizontal plane as well as in the vertical z direction.

[0117] Next, as shown in Fig. 2, a first fabric layer 111 can be placed onto the second fabric layer 112, which is already placed on the work table, using the suction device as handling mechanism 120. The fabric layers 111, 112 are aligned with each other such that, for example, the joining areas 114, 115, where the two fabric layers 111, 112 are to be joined, for example, by means of a seam, lie on top of each other and are aligned.

[0118] In a next step, as shown, for example, in Fig. 3, the fixation device 130 on the effector 101 is activated. In the exemplary illustration, the fixation mechanism 130 has a holding needle device 131, which penetrates holding needles 132 through the two fabric layers 111, 112 in order to hold them together in a fabric layer stack 113.

[0119] Subsequently, as shown in Fig. 4, the handling mechanism 120 is activated again, for example, by a suction cup / suction device creating negative pressure, thus attaching the fabric layer stack 113 to the effector 101. The effector 101 is then transported together with the fabric layer stack 113 to the sewing machine 140, so that the joining areas 114, 115 are precisely positioned in the processing area of ​​the sewing machine 140. The sewing machine 140 can then process the joining areas 114, 115.

[0120] Fig. 5 shows a schematic representation of a handling mechanism 120, which holds a stack of fabric layers 113 within an effector contour 501. The fixing mechanism 130 or the handling mechanism 120 has, within the outer joining regions 114, 115, an effector contour 501 with a fixing surface, in which a fixing force can be transferred to at least the fabric layers 111, 112.

[0121] The effector contour 501 describes the area on a fabric layer 111, 112 at which the fixation mechanism 130 and / or the handling mechanism 120 exerts a fixation or holding force. The effector contour 501 is defined, for example, by the border of the fixation surface or by the connecting lines between the individual fixation points at which there is holding contact with a held fabric layer 111, 112 within the xy plane. In the illustration in Fig. 5, a plurality of holding needles 132 have been inserted by the holding needle device 131 to hold the two fabric layers 111, 112 together. The connecting lines form the effector contour 501 within the fabric layer 111, 112.At the outer edge regions of the material layers 111, 112, which lie outside the effector contour 501, which is defined by the fixing points at which the handling mechanism holds the material layers 111, 112, the joining regions 114, 115 are formed and the material layer 111, 112 can be unstretched there and, so to speak, protrude from the xy plane.

[0122] Fig. 6 shows a schematic representation of a magnetic device as a fixing mechanism 130. The magnetic device has a magnetic element 601. The magnetic device can attract the magnetic element 601 toward the effector 101 such that the material layers 111, 112, which can be arranged between the effector 101 and the magnetic element 601, can be fixed. The magnetic element 601 can, for example, form a flat magnetic disc that flies under a lower material layer 111, 112 on the work table 103. Additional material layers 111, 112 can be placed over the lower material layers 111, 112. The magnetic device on the effector 101 can, for example, have a controllable electromagnet. Thus, the effector 101 can move to the fabric layer stack 113 and activate the magnetic device, so that the magnetic element 601 arranged below is attracted towards the magnetic device or effector 101 and fixes the intermediate fabric layers 111, 112.

[0123] Fig. 7 shows a schematic representation of an effector 101 with a contact surface 701 according to an exemplary embodiment. The contact surface 701, against which one of the fabric layers 111, 112 or the fabric layer stack 113 can be placed, is formed within the effector contour 501. The contact surface 701 forms, in particular, part of the handling mechanism 120 for securing one of the fabric layers or the fabric layer stack 113, wherein the contact surface 701 is designed to hold one of the fabric layers 111, 112 or the fabric layer stack 113 magnetically, based on air pressure, mechanically, or electrostatically to the effector 101. The contact surface 701 allows the fabric layers 111, 112 or the fabric layer stack 113 to be transported and later deposited without distortion or creases. After positioning or stacking the fabric layers 111, 112, the fabric layers can be fixed more easily using the contact surface 701.

[0124] The work surface 102 has a support device 702, which is configured to fix one of the material layers 111, 112 or the material layer stack 113 on the work surface 102 by means of a support force, in particular by means of pneumatic, mechanical and / or electrostatic support forces. The support device 702 is attached, for example, to the work table 103. The support device 702 can be based on pneumatic, electrostatic, or magnetic principles. For example, a ferromagnetic plate can lie on the work table 103, onto which a material layer 111, 112 is placed, which can later serve as the magnetic element 601 of the magnetic device.

[0125] Fig. 8 shows a schematic representation of an effector 101 with a handling mechanism 120 and a fixing mechanism 130 according to an exemplary embodiment. For example, the effector 101 can first be placed over a fabric layer stack 113 in order to insert holding pins 132 into the fabric layers 111, 112 so that the fabric layers 111, 112 are fastened to one another. In a next step, the effector 101 with the handling mechanism 120, which has, for example, a suction device, can be placed over the fabric layer stack 113 in order to hold it to the effector 101 and transport it further to a sewing machine 140.

[0126] Fig. 9 shows a schematic representation of a work table 103 with adhesion zones 901 with different levels of static friction, in particular with adjustable static friction. When positioning the first fabric layer 111, the second fabric layer 112, or the fabric layer stack 113, the handling mechanism 120 takes the different adhesion zones into account for aligning the fabric layers 111, 112. The work table 103 can have zones of different levels of friction / adhesion. Thus, it can be advantageous if the lower fabric layer 112 does not slip during precise placement for fixation because it has a high level of friction / adhesion relative to the work surface (while the upper fabric layer 111 is placed on it).Once both fabric layers 111, 112 are secured by the securing mechanism 130, the robot can lift the fabric layers 111, 112 using the handling mechanism 120 and reposition them in an area with better sliding properties for sewing, or adhesion to the work surface can be eliminated. The roughness of the work surface 102 of the work table 103 can be adjusted, for example, by providing retractable and extendable bristles 902. The bristles 902 can extend at right angles to the work surface 102 of the work table 103. Additionally or alternatively, bristles 901 can have an angle of less than 90° to the work surface 102 of the work table 103. Thus, a different friction can be adjusted via the bristles 902 depending on the direction of movement of the fabric layers 111, 112. In one exemplary embodiment, a control unit can control the extension of the bristles 902.Furthermore, the angle of the bristles can be adjusted in order to adjust the friction 902 and in particular the direction of friction with respect to the material layers 111, 112 via the bristles 902.

[0127] Fig. 10 shows a schematic representation of a handling mechanism 120 with a gripping device according to an exemplary embodiment of the present invention. A gripper 1001 of the gripping device is designed such that it encloses the edge of the fabric layer stack 113 and grips it from above and below, i.e., from the left and right sides of the fabric layer stack 113.

[0128] Fig. 11 shows a schematic representation of a handling mechanism 120 with a suction device according to an exemplary embodiment of the present invention. The suction device has a suction device 1101, wherein the suction device is designed to suck air from the first and second fabric layers 111, 112 by means of the suction device 1101 such that the superimposed first and second fabric layers 111, 112 can be secured to the suction device. Since the fabric layers 111, 112 are permeable to air to a certain extent due to their material properties, two or more fabric layers can be secured in a fabric layer stack 113 by means of suction with an appropriately adjusted suction power. The suction device has, for example, a vacuum pump, which can be arranged, for example, at a distance from the effector, for example, on the work table 103.

[0129] Fig. 12 shows a schematic representation of a handling mechanism 120 with an electrostatically charged attraction element 1201 according to an exemplary embodiment of the present invention. The electrostatically charged attraction element 1201 can, for example, be electrostatically charged in order to accordingly fix the fabric material of the fabric layers 111, 112. The electrostatic charge can be generated, for example, via a correspondingly connected power generation device controlled by the control unit 105.

[0130] Fig. 13 shows a schematic representation of a handling mechanism 120 with holding needles 1301 according to an exemplary embodiment of the present invention. The handling mechanism 120 has a holding needle device configured such that a penetration depth and / or a penetration angle of at least one holding needle 1301 is controllable, in particular in real time and / or based on sensor feedback. An additional form of differentiated gripping with the handling mechanism 120 can represent the depth of a holding needle 1301 and / or the angle of a holding needle 1301 (and in particular relate to a plurality thereof).

[0131] Fig. 14 shows a schematic representation of an effector 101 with several different handling mechanisms 120, for example, with a suction cup 1101 and holding needles 1301 according to an exemplary embodiment of the present invention. Fig. 15 shows a schematic representation of a handling mechanism 120 with a gripper 1001 that grips the top side of a fabric layer, according to an exemplary embodiment of the present invention. The gripper 1001 grips a portion of a surface of the fabric layer stack 113 in a pincer-like manner.

[0132] Fig. 16 shows a schematic representation of a handling mechanism 120 with a suction surface 1601 according to an exemplary embodiment of the present invention. The suction surface 1601 forms a contact surface 701 as part of the handling mechanism 120, against which one of the fabric layers 111, 112 or the fabric layer stack 113 can be placed. The suction surface 1601 has a plurality of suction openings 1602.

[0133] Fig. 17 to Fig. 19 show schematic representations of a fixing mechanism 130 with a folding device according to an exemplary embodiment of the present invention. The folding device is configured to fold over an edge region of a fabric layer 111 such that the folded edge region forms the first fabric layer 111, which lies on top of the second fabric layer 112. The folding device has a clamping element 1703 for clamping the folded first fabric layer 111 and the second fabric layer 112 together.

[0134] The folding device is attached to the work table 103 by means of a bearing 1704. A fixed support beam 1702 is arranged on the bearing 1704. Furthermore, the folding device has a movable folding beam 1701, which is movably arranged on the bearing 1704. The folding beam 1701 runs parallel to the support beam 1702 and can be pivoted about this support beam 1702. The folding beam 1701 and the support beam 1702 run parallel (and e.g., horizontally) to the work surface 102. As shown in Fig. 17, a fabric layer 111 is attached to a suction surface 1601 on the effector 101. Furthermore, a pivotable clamping element 1703 is arranged on the effector 101 or the suction surface 1601. The clamping element 1703 can be pivoted over an edge of the effector 101 or the suction surface 1601.In an initial position, the folding beam 1701 and the support beam 1702 are spaced apart so that a region of the fabric layer 111 can be positioned between the folding beam 1701 and the support beam 1702.

[0135] Subsequently, as shown in Fig. 18, the folding beam 1701 is pivoted around the support beam 1702, whereby the folding beam 1701 remains parallel to the support beam 1702 and a region of the fabric layers

[0136] 111 and thus folded around the support beam 1702. Accordingly, two material layers 111, 112 lie on top of each other. Between the effector 101 or the suction surface 1601 and the folding beam 1701 lies in particular the joining area 115 or an edge area of ​​the second material layer

[0137] 112. The clamping element 1703 is then pivoted over the edge of the effector 101 or the suction surface 1601 and clamps the two fabric layers 111, 112 together.

[0138] For this purpose, the effector 101 or the suction surface 1601 has a contact area 1705 against which an edge area of ​​the folded-over second fabric layer 112 rests, so that the clamping element 1703 can clamp this edge area or press it against the contact area 1705. The contact area 1705 can have a projection on the effector 101 or the suction surface 1601, which extends from an edge of the effector 101 or the suction surface 1601 and around which the fabric layer 112 rests after being folded over. In other words, the projection is arranged between the two fabric layers 111, 112 after being folded over. Furthermore, the length of the folded second fabric layer 112 can be longer than a distance between an edge of the effector 101 or the suction surface 1601 and the support bar 1702. Thus, an end region of the folded second fabric layer 112 is folded up and applied to the edge surface.The clamping element 1703 then pivots towards the edge surface and clamps the folded-up part of the second fabric layer 112.

[0139] As shown in Fig. 19, the effector 101 can pull out the fabric layers 111, 112 horizontally, in the extension direction of the folding bar 1701 and the support bar 1702, with the fabric layers 111, 112 being held in the folded position by the clamping element 1703. The effector 101 can now be pivoted into a horizontal position so that the fabric layers 111, 112 can rest flat on the work table 103. The clamping element 1703 continues to clamp the fabric layers 111, 112 together. The joining areas 114, 115 are shown at the free end, where the sewing machine 140 can, for example, sew a seam.

[0140] Fig. 20 shows a schematic representation of the folding device, which can be arranged on a work table 103. The folding beam 1701 and the support beam 1702 are attached at one end to the bearing 1704. Free ends are provided at the opposite ends of the folding beam 1701 and the support beam 1702. After the fabric layers 111, 112 have been folded over by means of the folding beam 1701, the effector 101 can be moved horizontally so that the folding beam 1701 is moved out of the pocket formed between the fabric layers 111, 112.

[0141] Fig. 21 shows a schematic representation of a fabric layer 111 with an overhang 2101 outside an effector contour 501, according to an exemplary embodiment. The fabric layer 111 has, for example, the shape of a shirt. The second fabric layer 112 is arranged below the fabric layer 111. The first fabric layer 111 has a plurality of fixing regions 2100. The fixing points of the handling mechanism 120 and / or the fixing mechanism 130 engage the fixing regions 2100. At the edge of the inner effector contour 501, in particular, fixing points such as the handling mechanism 120 are provided in order to lift the first fabric layer 111 under tension in a way that is as wrinkle-free as possible. Fixing elements for the fixing mechanism 130 can be provided inside the effector contour 501, to which the fixing mechanism 130 fixes both fabric layers 111, 112 together.For example, corresponding holding needles 132 of the holding needle device 131 can be inserted into the fixing elements of the fixing mechanism 130 in order to fasten both fabric layers 111, 112 together.

[0142] The effector contour 501 is smaller than the outer contour of the fabric layers 111, 112, so that in this area between the outer contour of the fabric layers 111, 112 and the effector contour 501, the overhang 2101 is formed, in which, in particular, the joining area 114 is formed. The effector can thus convey the fabric layers 111, 112 to a sewing machine 140, so that the sewing machine creates a corresponding seam in the joining area 114.

[0143] Fig. 22 to Fig. 24 show schematic representations of a handling mechanism 120 with holding needles 1301 according to an exemplary embodiment.

[0144] Holding needles 1301 are arranged on a control surface 2201 of the handling mechanism 120, wherein a surface shape of the control surface 2201 is adjustable such that in a first embodiment of the surface shape the holding needles 1301 are oriented parallel to one another (see Fig. 22) in order to penetrate into or extend out of at least one material layer 111, 112, and in a second embodiment of the surface shape the holding needles 1301 are not aligned parallel to one another (see Fig. 23 or Fig. 24) in order to fix them in at least one material layer 111, 112.

[0145] When the control surface bends, the retaining pins 1301 spread and fix the two fabric layers 111, 112. When the control surface bends back, for example, during a smooth movement or abruptly by clicking back, the retaining pins 1301, which are again aligned parallel to one another, detach from the fabric layers 111, 112. The surface shape of the control surface 2201 can be deformable and, in particular, prestressed by means of mechanical, pneumatic, or hydraulic elements. The elastic control surface 2201 can be deformable so that it can be prestressed and automatically deformed back into an initial position without external restoring force, for example, by having the retaining pins 1301 run parallel or by having the retaining pins 1301 at an angle to one another.

[0146] In the embodiment shown, a control chamber 2202 is formed between the effector 101 and the control surface 2201. The control chamber can be supplied with air (or a gas, in a hydraulic embodiment a hydraulic fluid) via an air line 2203. For example, an overpressure can be generated in the control chamber 2202, whereby the control surface 2201 deforms outwards and the holding needles 1301 are spread accordingly (see Fig. 23). Alternatively, air can also be drawn out of the control chamber 2202, so that a negative pressure is generated and the control surface 2201 deforms inwards (see Figure 24). Thus, the holding needles 1301 are pressed together at their tips. By means of the spread-apart or pressed-together holding needles 1301, a corresponding fabric layer 111, 112 can be held. Fig.25 shows a schematic representation of the positioning of a third fabric layer 2501 on two already sewn fabric layers 111, 112 according to another exemplary embodiment. A first fabric layer 111 and a second fabric layer 112 lie partially on top of one another on a work table 103 and have already been sewn together with a seam 2503, in particular using the method according to the invention. The handling mechanism 120 is equipped with a suction cup 1101, which already holds another third fabric layer 2501 within the effector contour 501. The edge regions of the third fabric layer 2501 are freely accessible and form a third joining region 2502. The effector 101 is controlled by the robot arm 104, so that the third fabric layer 2501 is placed over the first fabric layer 111. For example, the third joining region 2502 can thus lie above the seam 2503 and thus above the respective first and second joining regions 114, 115.The first fabric layer 111, the second fabric layer 112, and the third fabric layer 2501 can then be sewn together. The second fabric layer 112 can, for example, represent a label and can thus be sewn into a type of hem.

[0147] Additionally, it should be noted that "comprising" does not exclude other elements or steps, and "a" or "an" does not exclude a plurality. Furthermore, it should be noted that features or steps described with reference to one of the above embodiments may also be used in combination with other features or steps of other embodiments described above. Reference symbols in the claims are not to be considered as limiting. List of reference symbols:

[0148] 100 handling robots 901 adhesion area

[0149] 101 Effector 902 Bristles

[0150] 102 work surface

[0151] 103 Work table 1001 Gripper

[0152] 104 Robot arm 1101 Vacuum cleaner

[0153] 105 Control unit 1201 electrostatic

[0154] 111 first fabric part / fabric layer attraction element

[0155] 112 second fabric piece / fabric layer 1301 holding pins

[0156] 113 fabric layer stacks

[0157] 114 first joining area 1601 suction surface

[0158] 115 additional joining area 1602 intake opening

[0159] 120 Handling mechanism 1701 Folding beam

[0160] 130 Fixing mechanism 1702 Support beam

[0161] 131 Holding needle device 1703 Clamping element

[0162] 132 Holding pins 1704 Storage on the work table

[0163] 140 Sewing machine 1705 positioning area

[0164] 501 Effector contour 2100 Fixation area

[0165] 2101 Overhang

[0166] 601 Magnetic element 2201 Control surface

[0167] 2202 Control Chamber

[0168] 701 Effector contact surface 2203 Air line

[0169] 702 support device 2501 third fabric layer

[0170] 2502 third joining area

[0171] 2503 Seam

Claims

Patent claims 1. A method for robot-assisted sewing of fabric layers (111, 112) for clothing, the method comprising: Gripping a first layer of material (111) with a handling mechanism (120) of a handling robot (100) with an effector (101) for handling layers of material (111, 112), Positioning the first layer of fabric (111) over a second layer of fabric (112) which rests on a work table (103), Fixing the first fabric layer (111) with the second fabric layer (112) to form a fabric layer stack (113) by means of a fixing mechanism (130) which is arranged at least partially on the effector (101) in such a way that a joining region (114) of the first fabric layer (111) rests on a further joining region (115) of the second fabric layer (112), Feeding the fabric layer stack (113) to a sewing machine (140) by means of the handling mechanism (120), wherein the joining areas are freely accessible to the sewing machine (140), Sewing the joining areas, wherein during sewing the handling mechanism (120) guides the fabric layer stack (113) relative to the sewing machine (140), Handling the sewn fabric stack by means of the handling mechanism (120) from the sewing machine (140) to a storage location.

2. The method according to claim 1, wherein the handling mechanism (120) separates the second fabric layer (112) from a plurality of fabric layers and places it flat on a work surface (102) of the work table (103), so that the first fabric layer (111) is subsequently positioned over the second fabric layer (112).

3. Method according to claim 1 or 2, wherein the first fabric layer (111) and the second fabric layer (112) form regions of a fabric part, wherein the positioning of the first fabric layer (111) over the second fabric layer (112) by folding the fabric part, in particular by means of a folding device which is designed to fold over an edge region of the fabric part in such a way that the folded edge region forms the first fabric layer (111), which rests on the second fabric layer (112).

4. Method according to one of claims 1 to 3, wherein the first fabric layer (111) is fixed to the second fabric layer (112) by means of temporary fixing elements, in particular holding pins, which are removed during sewing, in particular taking into account the sewing progress, or after sewing.

5. Method according to one of claims 1 to 4, wherein a working surface (102) of the work table (103) has adhesive areas (901) with different static friction and the handling mechanism (120) when positioning the first fabric layer (111), the second fabric layer (112) or the fabric layer stack (113) uses the different adhesive areas (901) to align the first fabric layer (111), the second material layer (112) or the material layer stack (113) is taken into account, wherein the adhesion of the adhesive regions (901) is controllable.

6. The method according to claim 5, wherein the handling mechanism (120) moves the fabric layer stack (113) over the adhesive areas (901) in such a way that the position of the lower second fabric layer (112) is adjusted to the first upper material layer (111) due to the static friction to the adhesion area (901).

7. Method according to one of claims 1 to 6, wherein during sewing, the handling mechanism (120) moves the fabric layer stack (113) with a first feed relative to the sewing machine (140), wherein the sewing machine (140) moves the fabric layer stack (113) with a second feed, wherein the handling mechanism (120) in particular controls the first feed differently from the second feed of the sewing machine (140).

8. The method according to any one of claims 1 to 7, wherein after the step of sewing, the method comprises Gripping a third fabric layer (2501) with the handling mechanism (120), positioning the third fabric layer (2501) over the sewn first and second fabric layers (111, 112), which rest on a work table (103), fixing the third fabric layer (2501) with the sewn first and second fabric layers (111, 112) to form a fabric layer stack (113) by means of the fixing mechanism (130), such that a further joining area (2502) of the third fabric layer (2501) rests on a further joining area (2502) of the first and / or second fabric layer (111, 112), Feeding the fabric layer stack (113) to the sewing machine (140) by means of the handling mechanism (120), and Sewing the further joining areas, wherein during sewing the handling mechanism (120) guides the fabric layer stack (113) relative to the sewing machine (140).

9. The method according to any one of claims 1 to 8, wherein the fixing mechanism (130) fixes the first and second fabric layers (111, 112) along at least one fixing region (2100) and / or along a plurality of spaced fixing regions (2100).

10. Method according to claim 9, wherein the fixation areas (2100) have an area of ​​less than 1 cm 2 , especially less than 20 mm 2 , especially less than 8 mm 2 and / or wherein the fixing regions (2100) are spaced apart by more than 2 cm, in particular more than 3 cm or more than 4 cm.

11. The method according to claim 9 or 10, wherein during or after the sewing at least one of the fixing regions (2100) is separated, wherein the fixing region (2100) is separated in particular at a separation speed which is coordinated with the feed during the sewing and substantially corresponds to it.

12. Method according to one of claims 1 to 11, wherein the work surface (102) of the work table (103) is movably mounted and is moved, wherein in particular the movement of the work surface (102) takes place synchronously with the movement of the effector (101), wherein the movement of the work surface (102) takes place in particular during sewing, wherein the work table (103) in particular has a conveyor belt as a work surface (102) for conveying at least one layer of fabric (111, 112) placed thereon relative to the sewing machine (140), wherein in particular the movement of the work surface (102), the handling mechanism (120) and the feed of the sewing machine (140) are synchronized.

13. Method according to one of claims 1 to 12, wherein the handling mechanism (120) has an effector contour (501), wherein one of the fabric layers (111, 112) or the fabric layer stack (113) can be fastened within the effector contour (501), wherein the effector contour (501) is smaller than an outer contour of the fabric layer (111, 112) or of the fabric layer stack (113), wherein the handling mechanism (120) is designed such that the joining regions of the fabric layers (111, 112) form a projection (2101) of more than 0.5 cm, in particular more than 1 cm, further in particular more than 2 cm or more than 3 cm, relative to the effector contour (501).

14. The method according to one of claims 1 to 13, wherein the handling mechanism (120) with a holding needle device introduces holding needles (1301) with a predetermined piercing depth and / or a predetermined piercing angle into the first fabric layer (111) or the fabric layer stack (113) for attachment to the effector (101), wherein the predetermined piercing depth and / or the predetermined piercing angle is determined in particular in real time and / or based on sensor feedback, wherein the holding needles (202) in particular have a diameter of less than 1300 micrometers, less than 900 micrometers, in particular less than 550 micrometers, further in particular less than 250 micrometers.

15. Method according to one of claims 1 to 14, wherein at least one of the material layers (111, 112) is fixed to the work surface (102) by means of a holding-down device (505) on the work table (103), wherein the holding-down device (505) is designed to selectively fix at least one of the material layers (111, 112) to the work table (103), in particular by means of pneumatic, mechanical and / or electrostatic holding forces, wherein the work surface (102) is in particular embedded in the work table (103) and the work surface (102) is in particular designed as a work plate with a thickness of less than 1 cm, in particular less than 5 mm or less than 3 mm, wherein the fabric layer stack (113) is placed on the work surface (102) in particular in such a way that the fabric layer stack (113) forms an overhang (2101) to at least part of the work surface (102).

16. Method according to one of claims 1 to 15, Determining fabric layer data relating in particular to fabric layer material and / or fabric layer geometry, and / or Determining processing data, in particular left / right position, alignment, folds and / or manufacturing quality of one of the fabric layers (111, 112) or the fabric layer stack (113), and / or Determining positioning, placement, fixation during sewing and / or sewing quality, and Evaluation of the collected data to determine the quality of the sewn fabric layers (111, 112).

17. The method according to any one of claims 1 to 16, wherein the fixing step comprises supplying adhesive for temporarily bonding the first fabric layer (111) and the second fabric layer (112) together, wherein the adhesive contains in particular a water-soluble polymer, in particular polyethylene glycol and / or polyvinyl alcohol, Na thiosulfate pentahydrate, Na acetate trihydrate, ammonium alum dodecahydrate, urea and / or eutectic salt mixtures, wherein the adhesive comprises in particular a pressure-activated adhesive, a hot melt adhesive and / or a two-component adhesive, in particular that the adhesive is removable again during and / or after a further processing step, in particular is detachable together with a material part of the first fabric layer (111), the second fabric layer (112) and / or the fabric layer stack (113).

18. Method according to one of claims 1 to 17, wherein a seam end is detected during sewing, wherein during sewing at the seam end the feed of the handling device and / or the sewing machine (140) is changed at the seam end in order to vary a tension of the fabric layers (111, 112) between the sewing machine (140) and the effector (101) in strength and / or direction.

19. Method according to one of claims 1 to 18, wherein after sewing, a thread with a predetermined thread length is cut off after an end of the seam, wherein the handling mechanism (120) moves the fabric layer stack (113) relative to a thread cutting device in such a way that the thread length is adjustable.

20. Method according to one of claims 1 to 19, wherein a heating device for heating the fabric layers (111, 112) and / or a moistening device for moistening the fabric layers (111, 112) is arranged on the work table (103) in order to smooth, in particular to iron, at least one of the fabric layers (111, 112) and / or the fabric layer stack.

21. Method according to one of claims 1 to 20, wherein at least one further sewing device is arranged on the work table (103) so that during or after the sewing of the joining areas, the further sewing device sews further joining areas of the first and second fabric layers (111, 112), wherein the sewing device and the further sewing device in particular form different types of seams, in particular an overlock seam and a coverstitch seam, in the joining areas.

22. Program element for robot-assisted sewing of fabric layers (111, 112) for clothing, which, when executed by a processor, is arranged to carry out the method according to one of claims 1 to 21.

23. System for robot-assisted sewing of fabric layers (111, 112) for clothing, the system comprising: a handling robot (100) with an effector (101), which has a handling mechanism (120) for handling fabric layers (111, 112), wherein the handling mechanism (120) is designed to grip a first fabric layer (111), wherein the handling mechanism (120) is configured to position the first fabric layer (111) over a second fabric layer (112) which rests on a work table (103), a fixing mechanism (130) which is at least partially arranged on the effector (101), wherein the fixing mechanism (130) is designed to fix the first fabric layer (111) and the second fabric layer (112) to one another to form a fabric layer stack (113) in such a way that a joining region (114) of the first fabric layer (111) rests on a further joining area (115) of the second fabric layer (112), a sewing machine (140), wherein the handling mechanism (120) is configured,feeding the fabric layer stack (113) to the sewing machine (140), wherein the joining areas are freely accessible to the sewing machine (140), wherein the sewing machine (140) is configured to sew the joining areas, wherein the handling mechanism (120) is configured to guide the fabric layer stack (113) relative to the sewing machine (140) during the sewing, wherein the handling mechanism (120) is configured to transport the sewn fabric stack (113) from the sewing machine (140) to a storage location.

24. System according to claim 23, wherein the handling mechanism (120) is selected from the group consisting of grippers (1001), suction cups (1101), clamps, areas of increased friction and / or electrostatic attraction, rollers, freezing grippers, and / or Bernoulli grippers.

25. System according to claim 23 or 24, wherein the sewing machine (140) has a presser foot with a presser foot length in the conveying direction of the fabric layers (111, 112) to be sewn, wherein a presser foot length in the conveying direction is greater than 20 mm, greater than 40 mm, or greater than 60 mm.

26. System according to one of claims 23 to 25, wherein the handling mechanism (120) comprises holding needles which penetrate at least into the first fabric layer (111), the second fabric layer (112) and / or the fabric layer stack (113) in order to attach them to the effector (101).

27. System according to claim 26, wherein holding needles are arranged on a control surface (2201) of the handling mechanism (120), wherein a surface shape of the control surface (2201) is adjustable such that in a first embodiment of the surface shape the holding needles are oriented parallel to one another in order to penetrate or extend into at least one fabric layer (111), and in a second embodiment of the surface shape the holding needles are not aligned parallel to one another in order to fix them in at least one fabric layer (111).

28. System according to claim 27, wherein the surface shape of the control surface (2201) can be prestressed by means of pneumatic, mechanical or hydraulic elements.

29. System according to one of claims 23 to 28, wherein the effector (101) has a contact surface (701) within an effector contour (501), against which one of the fabric layers (111, 112) or the fabric layer stack (113) can be placed, wherein the contact surface (701) in particular forms part of the handling mechanism (120) for fixing one of the fabric layers (111, 112) or the fabric layer stack (113), wherein the contact surface (701) is designed such that one of the fabric layers (111, 112) or the fabric layer stack (113) is held magnetically, based on air pressure, mechanically or electrostatically on the effector (101).

30. System according to claim 29, wherein the contact surface (701) as part of the handling mechanism (120) forms a suction surface (1601) against which one of the fabric layers (111, 112) or the fabric layer stack (113) can be placed, wherein the suction surface (1601) has a plurality of suction openings (1602), in particular more than 9, more than 15, more than 22 and / or more than 30 suction openings (1602), wherein the suction openings (1602) are designed in particular with a diameter of less than 20 mm, in particular less than 10 mm, further in particular less than 5 mm, further in particular less than 3 mm.

31. System according to claim 30, wherein a negative pressure on the suction surface for holding the fabric layers (111, 112) or the fabric layer stack (113) is adjustable such that the negative pressure can be varied by more than 15%, in particular more than 30% or more than 45%.

32. System according to one of claims 23 to 31, wherein the fixing mechanism (130) comprises a welding device, in particular an ultrasonic welding device, for, in particular temporarily, welding the first and second fabric layers (111, 112) together, wherein the fixing mechanism (130) comprises in particular a feeding device for feeding welding material, and / or wherein the fixing mechanism (130) comprises a suction device with at least one suction device (1101), wherein the suction device is designed to suck air from the first and second fabric layers (111, 112) by means of the suction device (1101) in such a way that the superimposed first and second fabric layers (111, 112) can be fixed to the suction device, and / or wherein the fixing mechanism (130) comprises a magnetic device which is designed to attract a magnetic element in the direction of the effector (101) in such a way that the fabric layers (111, 112),which can be arranged between the effector (101) and the magnetic element, and / or wherein the fixing mechanism (130) has a clamping device which is configured to clamp the first fabric layer (111) and the second fabric layer (112) together, and / or wherein the fixing mechanism (130) has an adhesive device which is configured to temporarily bond the first fabric layer (111) and the second fabric layer (112) together, and / or wherein the fixing mechanism (130) has a holding needle device (131) which is configured to introduce holding needles (132) into the first fabric layer (111) and the second fabric layer (112) for fixing, and / or wherein the fixing mechanism (130) has a stapling device which is configured to introduce at least one staple into the first fabric layer (111) and the second fabric layer (112) for fixing, and / or wherein the fixing mechanism (130) has a hold-down device,which is arranged to apply a contact force to the first material layer (111) and the second material layer (112) in the direction of the working surface (102).

33. System according to one of claims 23 to 32, wherein the handling mechanism (120) has a support element, in particular a support plate, for placing the stack of fabric layers (113) to be conveyed, wherein the handling mechanism (120) is in particular configured such that the first fabric layer (111) and second fabric layer (112) fixed by the fixing mechanism (130) can be lifted together and the support element can be conveyed under the fixed first fabric layer (111) and second fabric layer (112).

Images