Fabric handling dual manipulator system with fabric hoisting end effector

Abstract

A fabric handling manipulator system for handling a target fabric piece includes a first robotic manipulator, a second robotic manipulator, a first reeling end effector positioned by the first robotic manipulator, the first reeling end effector adapted to grip a first end of the target fabric piece with a roller having a suction port, a second reeling end effector positioned by the second robotic manipulator, the second reeling end effector adapted to grip a second end of the target fabric piece with a roller having a suction port, a first force sensor, a second force sensor, and a visual sensor system configured and adapted to sense the orientation of the end effector. This system has many advantages, including a simple mechanical structure that improves roller access to smaller sized fabric pieces and increases the effective working range of the end effector. A method for handling a target fabric piece is also provided.

Description

[Background technology]

[0001] Most clothing production processes that require precise manipulation of fabric pieces, such as sewing, are still performed manually by human workers. Fabrics are difficult to handle because they are thin, soft, flexible, and deformable, so dexterous human hands are required for fabric handling operations.

[0002] To increase production efficiency, parts of the garment production process are implemented using automated systems. Existing automated systems for sewing or handling operations require fixtures specifically designed to clamp fabric pieces of a specific size and shape. The fixtures grip the fabric pieces and uniquely determine the orientation of the fabric pieces relative to the fixture's orientation. For example, sewing operations are performed by manipulating the position of the fixture, which provides a guide slot for a sewing needle that limits the path of the stitch. Fabric pieces clamped by the fixture receive sufficient mechanical support to maintain their shape, making them easier to handle by the automated system. While this style of automation using fixtures is efficient for mass production of garments with the same design, it has several drawbacks. Common problems associated with the use of fixtures include: (i) each fixture is applicable only to a particular size and shape of fabric piece and not to other dissimilar fabric pieces, thereby requiring automated systems to have fixtures specifically designed for each type of target fabric piece being sewn or processed; (ii) the additional time and cost involved in fabricating such fixtures; and (iii) the additional time and cost involved in installing and replacing fixtures between production runs.

[0003] Robotic gripping devices for handling flexible textile materials without dedicated fixtures have been investigated and reported worldwide by various research groups since the 1980s. These reported devices can be broadly categorized according to their realization mechanisms, including mechanical, electrostatic, airflow, adhesive, and rotatable drum technologies.

[0004] I. Mechanical technology

[0005] Robotic grippers employing a typical "two-finger" structure have perhaps been most frequently studied for fabric handling due to their common use in conventional robotic systems. Depending on the design, these mechanical grippers can perform clamping, pinching, and sometimes hooking with the aid of additional pins / needles. Gripping is facilitated by small-area contact or even point contact. We have identified several research groups that have attempted to use mechanical grippers (and no fixtures) to handle fabric pieces of different sizes and shapes. Some recent examples are outlined below.

[0006] Schrimpf et al. (2015) present a system with a "two-finger" mechanical gripper attached to a robotic arm that can handle pieces of fabric to a sewing machine. However, this mechanism can only move the pieces of fabric and cannot vary the tension applied to individual pieces of fabric.

[0007] Stria (2014) and L. Sun (2015) utilized the same dual-manipulator robot system under the CloPeMa (Clothes Perception and Manipulation) project, which used a "two-finger" gripper and a camera attached to each robotic manipulator. This was used to pinch and fold corners of an item of clothing. The task was aided by visual information, and no tension control was reported.

[0008] Shibata (2009, 2012) reported a mechanism consisting of a "two-finger" gripper mounted on a linear rail. This was used to "pinch and grasp" a piece of fabric and release it at another location. This design has the disadvantage that it only allows linear relative motion of the grippers and is not force-sensitive. Even if tension control can be implemented in such a system, tension can only be applied along the straight line defined by the linear rail.

[0009] Aranda (2020) presents a study focusing on shape servoing, where a “two-fingered” gripper was used to handle deformable objects with the help of computer vision.

[0010] Tanaka (2021) also presents a robotic mechanism that uses a "two-finger" gripper to perform cloth folding. The main difference with other related technical mechanisms is the use of a humanoid robot, although the working principle of the end effector is similar.

[0011] Ku (2020) reported a special design of a fabric gripper that uses embedded microneedles and suction. The gripping strategy involves pinching the fabric with two claws and lifting it with suction. Such a design has not been shown (and is not expected) to be effective for handling / positioning fabric due to its limited gripping force and small contact area with the fabric.

[0012] The end effector developed by Yamazaki (2021) teaches a brush-like roller to more firmly grip fabric objects. This design did not use suction. Fabric pick-up is required for the task, but the amount of pick-up is severely limited by the end effector design. Furthermore, once the fabric is engaged and interlocked by the bristle elements on the roller, releasing the fabric can be problematic.

[0013] Hinwood (2020) teaches an alternative end-effector design derived from human finger gestures that can provide a more secure grip on fabric. Otherwise, the device functions in essentially the same way as a typical "two-finger" gripper.

[0014] II. Electrostatic Technology

[0015] Electroadhesion has been used to handle fabric materials. One example is shown by B. Sun (2019), in which an electrostatic gripper device with multiple electroadhesion pads was used to grab a fabric panel. Weak adhesion is one of the recognized drawbacks of electrostatic grippers. Also, the surface area of ​​this type of gripper must be comparable to the size of the fabric panel to reliably handle the fabric.

[0016] III.Airflow Technology

[0017] Besides directly applying vacuum suction, end effectors using regulated airflow (or air jets) can also create a negative pressure effect that attracts textile materials based on Bernoulli's principle. Ozcelik (2003) developed a "non-contact" end effector for handling materials, including textiles, using a radial outward airflow.

[0018] Here, in the absence of physical contact, the stability of the fabric during the lifting and transfer process is highly uncertain. Under frictional resistance, the airflow leaving the fabric becomes turbulent and can cause thin, lightweight fabrics to flap unnecessarily at the free edges / corners, which is detrimental to accurate positioning. Another concern with such devices is that the "suction area" obtained by the nozzle is usually limited. To increase the area of ​​the "suction area," the nozzle needs to be larger, and maintaining the laminar airflow on which the gravitational force is derived becomes more difficult with larger flows.

[0019] IV. Adhesion technology

[0020] Another type of end effector known for fabric handling is based on adhesive or adhesive tape. A typical design of the device consists of a tape dispenser and a motorized feeding mechanism, as shown in a paper published by Parker et al. (1983).

[0021] Adhesive grippers offer advantages such as simple design and low likelihood of picking up multiple fabric layers at once from a stack of fabric layers. Nevertheless, they require an effective release mechanism to remove the fabric from the adhesive, which adds complexity to the mechanical design and process control and has rarely been studied or reported in the literature.

[0022] V. Rotatable Drum Technology

[0023] US Patent No. 7,601,237 (B2) relates to an apparatus, robotic system, and method for handling fabrics for constructing composite materials for aircraft. The apparatus comprises a rotatable drum assembly with one or more suction ports on the drum surface. The robotic system comprises a movable gantry-type frame, a robotic arm attached to the frame, and an apparatus attached to the end of the robotic arm.

[0024] A similar device and method for handling flexible materials is disclosed by U.S. Patent Application Publication No. 2018 / 0154539(A1). The subject system picks up a cut piece of flexible material. The system includes a pick head, a pick head positioning device, and a platform on which the flexible material is located. The pick head consists of a rotatable cylinder with multiple suction openings.

[0025] Both of the above systems use suction to first acquire the target material placed on a platform and then spool the material around a drum or cylindrical surface.

[0026] VI. Additional Commercial References

[0027] There are a few companies developing automation technology for fabric handling without specially designed fixtures. SoftWear Automation, Inc. and Sewbo, Inc. have developed automated garment production systems and methods, such as:

[0028] Developed by SoftWear Automation, Inc. (Atlanta, Georgia), Sewbot is a fully automated garment production system for a variety of clothing products, including bath mats, pillowcases, jeans, dress shirts, and T-shirts. The T-shirt Sewbot Workline produces T-shirts from pre-cut pieces of fabric without the need for human intervention. The production line primarily comprises a conveyor table, a sewing unit, and a visual sensor system. The conveyor table features a regularly arranged spherical roller on its surface for transporting the fabric pieces. The sewing operation is performed in the sewing unit using visual information acquired by the visual sensor system.

[0029] Sewbo, Inc. (San Francisco, California) has developed a method to automate fabric manufacturing by temporarily stiffening pieces of fabric. A water-soluble stiffening agent (polyvinyl alcohol) stiffens the fabric, making it easier for industrial robots to handle. After the fabric manufacturing process is complete, the stiffening agent is removed by rinsing with warm water, and the fabric is then thoroughly dried to restore its original texture. Summary of the Invention [Means for solving the problem]

[0030] Embodiments of the subject invention provide a novel end effector and robotic system capable of handling fabric pieces of different sizes and shapes without the use of fixtures. In certain embodiments, the provided robotic system may include two or more robotic manipulators, each equipped with a force sensor and an end effector, and a vision sensor system. The robotic system can grasp various types of fabric pieces while holding them flat with one or both manipulators, which are operable to (i) grip the fabric piece and (ii) control the tension applied to the fabric piece. The manipulators can accurately position the grasped fabric piece using visual information obtained by the vision sensor system and then perform the fabric piece handling task. The entire handling process does not require any custom-designed fixtures, minimizing reconfiguration efforts in the production line when product designs change. The sewing path can be numerically programmed, controlled, and visualized by the robotic system.

[0031] Experiments were conducted to grasp fabric pieces using a prototype of a single robotic manipulator and end effector. The experimental results demonstrated that a single end effector can grasp a variety of fabric pieces with different shapes. Fabric handling experiments were also conducted using a dual-manipulator system to demonstrate the functionality of the provided robotic system. Embodiments using the basic design concept and physical structure of the system were established, tested, and proven. Embodiments of the robotic apparatus and fabric handling method will be useful in commercial garment production procedures.

[0032] Existing automated systems for sewing or fabric handling operations use fixtures designed to clamp fabric pieces of a specific size and shape. The fixtures uniquely determine the orientation of the clamped fabric piece and keep it flat. The orientation of the clamped fabric piece is precisely controlled by positioning the fixture's orientation. Each fixture is applicable only to fabric pieces of the same size and shape, and is not applicable to fabric pieces with other shapes or dimensions. As a result, automated systems require fixtures specifically designed for each type of target fabric piece. Because preparing each specifically designed fixture is time-consuming and costly, traditional automation strategies using fixtures are not suitable for flexible garment production, especially for high-mix, low-volume production, which requires handling fabric pieces with different shapes as dictated by the production plan.

[0033] Embodiments of the subject invention provide an end effector and robotic system for handling various sizes or shapes of fabric pieces without fixtures. The provided robotic system comprises one or more robotic manipulators, each equipped with a force sensor and an end effector, and a vision sensor system. The end effector can have a roller unit with a suction port to pick up and roll up the fabric piece for easy transport using the manipulator. After transport, the end effector can unroll and lay the fabric piece flat at a desired location. The end effector can grip various types of fabric pieces with different dimensions by varying the rolling strategy.

[0034] Certain embodiments advantageously employ dual manipulators. A dual manipulator system can comprise, consist essentially of, or consist of two robotic manipulators (e.g., two robotic arms). A dual manipulator system can provide an advantageous configuration of the subject invention, in part because it effectively applies controllable tension to the fabric, allowing the coordinated movement of the two (or more) arms to maintain the shape of the fabric. A dual manipulator system can be advantageously combined with a reeling end effector embodiment to firmly grasp a target fabric piece by gripping the fabric piece on two sides (e.g., opposite sides) with the end effector. Force sensors attached to the manipulators can be used to control the tension applied to the handled fabric piece (e.g., as shown in FIG. 1 ) and to flatten the fabric piece without wrinkles or sagging during the positioning process. The handled fabric piece can ultimately be handled into a target pose using visual information acquired by a visual sensor system. The provided robotic system configuration, robotic end effector mechanical structure, and method for handling different sized pieces of fabric each offer advantages over related art systems and methods.

[0035] In the related art, robotic grippers employing various "two-finger" structures, airflow, electrostatic, adhesive, and rotating drum technologies have been unable to effectively handle a wide range of fabric sizes and shapes, despite their relatively complex mechanisms and larger footprints. In contrast, the suction rollers of certain embodiments of the subject invention can handle a wide range of fabric sizes, yet have a relatively small footprint. When operated in conjunction with dual manipulators and force (or torque) sensors, the suction rollers can apply uniform and controllable tension to the fabric to maintain its shape. These are significant differences in the design and working principles of the provided methods, robotic systems, and end effector embodiments relative to the related art.

[0036] One advantage of embodiments of the subject invention is that while the referenced related art teaches a yoke frame or gantry that rotatably supports the roller at both ends, the roller in certain embodiments of the subject invention is supported at only one end, which has many advantages, such as a simpler mechanical structure that improves roller access to smaller sized pieces of fabric and increases the effective working range of the end effector.

[0037] The use of an internal roller shaft to support the outer roller is a differentiating feature advantageously employed in certain embodiments of the subject invention. Related art may use an internal tube containing multiple branches for vacuum distribution. In certain related art, the internal tube and branches are rotatable independently of the pickup drum. In certain embodiments of the subject invention, the internal roller shaft (e.g., as shown in Figures 3B and 3C) not only functions as a suction passage but also as a support for the outer roller. It does not have a branching structure, but has two (or more) slots extending along its length through which air can flow toward the vacuum source. In certain embodiments, the internal roller shaft is fixed and not rotatable. The outer roller includes only one slot whose position can be precisely controlled by a motor, and the slot is advantageously controlled to face downward before engaging the fabric piece being handled.

[0038] Unlike related art systems, embodiments of the subject invention are capable of controlled distribution of force and tension in a target fabric piece across a two-dimensional workspace, which is advantageous for fabric handling and positioning.

[0039] Another advantageous embodiment of the outer roller can include a slot of varying width (e.g., narrowing at the proximal end and widening toward the distal end). One advantage of having a varying slot width design is that a vacuum source can be connected to the roller from the proximal end, and suction airflow can decrease toward the distal end due to frictional losses. Increasing the port width at the distal end can increase the airflow volume and thus the magnitude of suction near the distal end. The suction port in such an embodiment can be a single slot (e.g., as shown in Figures 2A and 2B) or multiple slots, the type of which can be advantageously designed based on the size, shape, and mass of the target fabric piece. Also, embodiments with varying suction port shapes (e.g., those using square, triangular, segmented, slotted, circular, irregular, spiral, or helical shapes) are considered within the scope of the subject invention.

[0040] In contrast to related art systems, embodiments of the subject invention do not require a yoke frame or gantry, but simply provide a roller supported by a sufficiently strong bearing at one end; the rotor is actuated by a motor via torque transmission by a belt and pulley, and the roller is supported by a non-rotatable fixed shaft. Some embodiments provide support by two or more ball bearings (alternatively, bushings, sleeves, needle bearings, cartridge bearings, or other rotatable supports known in the art) at two or more adjacent or spaced locations along the length of the roller. Alternative embodiments provide sufficient support via a single ball bearing (alternatively, a single bushing, sleeve, needle bearing, cartridge bearing, or other rotatable support known in the art) at a single location, optionally at one end or side of the roller (alternatively, at the center, the central third, or distributed along the roller). [Brief explanation of the drawings]

[0041] [Figure 1]FIG. 1 shows an example of a block diagram of tension control for a dual manipulator system according to an embodiment of the subject invention.

[0042] [Figure 2A] Shown are side views of four rollers each having a straight slot (top), a separated slot (second from the top), a tapered slot (second from the bottom), and a separated tapered slot (bottom) according to one embodiment of the subject invention.

[0043] [Figure 2B] 1 shows a perspective view of four rollers each having a straight slot (top left), a separated slot (bottom left), a tapered slot (top right), and a separated tapered slot (bottom right) according to one embodiment of the subject invention.

[0044] [Figure 3A] 3C shows a front view of the end effector with the partial cross section taken along section line AA of FIG. 3C, in accordance with one embodiment of the subject invention.

[0045] [Figure 3B] 1 shows a side view of a roller shaft having slots for suction airflow to a vacuum source, according to one embodiment of the subject invention.

[0046] [Figure 3C] 3B shows a partial cross-sectional view of the end effector of FIG. 3A taken along cross-sectional line AA, in accordance with one embodiment of the subject invention.

[0047] [Figure 3D] FIG. 1 shows a side view of an end effector according to one embodiment of the subject invention.

[0048] [Figure 4A] 1 illustrates a fabric handling workflow using a single-manipulator system according to one embodiment of the subject invention. The pose of the gripped fabric piece can be accurately positioned using visual information acquired by a visual sensor system.

[0049] [Figure 4B] 1 illustrates a fabric handling workflow using a single-manipulator system according to one embodiment of the subject invention. The pose of the gripped fabric piece can be accurately positioned using visual information acquired by a visual sensor system. [Figure 4C] 1 illustrates a fabric handling workflow using a single-manipulator system according to one embodiment of the subject invention. The pose of the gripped fabric piece can be accurately positioned using visual information acquired by a visual sensor system. [Figure 4D] 1 illustrates a fabric handling workflow using a single-manipulator system according to one embodiment of the subject invention. The pose of the gripped fabric piece can be accurately positioned using visual information acquired by a visual sensor system. [Figure 4E] 1 illustrates a fabric handling workflow using a single-manipulator system according to one embodiment of the subject invention. The pose of the gripped fabric piece can be accurately positioned using visual information acquired by a visual sensor system. [Figure 4F] 1 illustrates a fabric handling workflow using a single-manipulator system according to one embodiment of the subject invention. The pose of the gripped fabric piece can be accurately positioned using visual information acquired by a visual sensor system. [Figure 4G] 1 illustrates a fabric handling workflow using a single-manipulator system according to one embodiment of the subject invention. The pose of the gripped fabric piece can be accurately positioned using visual information acquired by a visual sensor system. [Figure 4H] 1 illustrates a fabric handling workflow using a single-manipulator system according to one embodiment of the subject invention. The pose of the gripped fabric piece can be accurately positioned using visual information acquired by a visual sensor system. [Figure 4I]1 illustrates a fabric handling workflow using a single-manipulator system according to one embodiment of the subject invention. The pose of the gripped fabric piece can be accurately positioned using visual information acquired by a visual sensor system.

[0050] [Figure 5A] 1 illustrates a fabric rolling operation using a single manipulator system that synchronizes the motion of the roller with the motion of the end effector to remove wrinkles or slack in a target piece of fabric, according to one embodiment of the subject invention. [Figure 5B] 1 illustrates a fabric rolling operation using a single manipulator system that synchronizes the motion of the roller with the motion of the end effector to remove wrinkles or slack in a target piece of fabric, according to one embodiment of the subject invention. [Figure 5C] 1 illustrates a fabric rolling operation using a single manipulator system that synchronizes the motion of the roller with the motion of the end effector to remove wrinkles or slack in a target piece of fabric, according to one embodiment of the subject invention. [Figure 5D] 1 illustrates a fabric rolling operation using a single manipulator system that synchronizes the motion of the roller with the motion of the end effector to remove wrinkles or slack in a target piece of fabric, according to one embodiment of the subject invention.

[0051] [Figure 6A] Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system. [Figure 6B]Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system. [Figure 6C] Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system. [Figure 6D] Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system. [Figure 6E]Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system. [Figure 6F] Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system. [Figure 6G] Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system. [Figure 6H]Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system. [Figure 6I] Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system. [Figure 6J] Illustrates a fabric handling workflow using a dual-manipulator system according to one embodiment of the subject invention. The robotic system consists of two robotic manipulators equipped with force sensors and reeling end effectors, and a visual sensor system. The dual-manipulator system handles a piece of fabric or multiple pieces of fabric by grasping them with the end effectors. The force sensor is used to control the tension applied to the grasped fabric piece and keep it flat. The pose of the grasped fabric piece can be accurately located using visual information acquired by the visual sensor system.

[0052] [Figure 7A] 1 illustrates an end effector according to another embodiment of the subject invention. [Figure 7B]1 illustrates an end effector according to another embodiment of the subject invention. [Figure 7C] 1 illustrates an end effector according to another embodiment of the subject invention. [Figure 7D] 1 illustrates an end effector according to another embodiment of the subject invention.

[0053] [Figure 8A] 7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. [Figure 8B] 7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. [Figure 8C] 7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. [Figure 8D] 7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. [Figure 8E] 7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. [Figure 8F] 7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. [Figure 8G] 7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. [Figure 8H] 7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. [Figure 8I] 7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. [Figure 8J]7A-7D illustrate a fabric handling workflow using a dual manipulator system according to the embodiment shown in FIGS. DETAILED DESCRIPTION OF THE INVENTION

[0054] 1 shows a block diagram of tension control 100 for a dual-manipulator system according to one embodiment of the subject invention. A trajectory generator 110 is connected to a force feedback module 120 and both a first manipulator control module 130 and a second manipulator control module 140. The trajectory generator 110 transmits desired position signals DP1 and DP2. The force feedback module 120 transmits position command signals PC1 and PC2, respectively. The first manipulator control module 130 and the second manipulator control module 140 transmit first position feedback signals PF1 and PF2, and first force feedback signals F1 and F2, respectively.

[0055] In the force feedback module 120, the tension controller 121 takes in F1, PF1, F2, and PF2, respectively, and sends out PC1 and PC2. In the first manipulator control module 130, the controller 131 takes in the combined signal of (DP1+PC1-PF1) and generates a control signal to the manipulator 132 with the force sensor 132a. In the second manipulator control module 140, the controller 141 takes in the combined signal of (DP2+PC2-PF2) and generates a control signal to the manipulator 142 with the force sensor 142a. This embodiment controls force and position in a coordinated manner, allowing both manipulators to work in unison to control the position and tension on the target fabric piece.

[0056] Although not shown in this embodiment, alternative embodiments may include third, fourth, or additional manipulator control modules, such as duplicates of either module 130, module 140, or both, along with all associated components, connections, signals, and functionality (e.g., duplicates of DP1, PC1, PF1, 131, 132, 132a, P1, PF1, F1 in FIG. 1, and all necessary connections).

[0057] A set of end effectors 200 according to an embodiment of the subject invention is shown in Figures 2A and 2B. The end effectors can have roller units with suction ports opening into the roller surfaces. A motor can be installed in the end effector, and rotation can be controlled by transmitting torque to the rollers through an appropriate transmission mechanism, such as gears, pulleys, and belts. Illustrated are end effector 210 with a single suction port slot of uniform width, end effector 220 with separate suction port slots of uniform width, end effector 230 with a single suction port slot of varying width, and end effector 240 with separate suction port slots of varying width.

[0058] 3A shows a front view of end effector 300 with the partial cross section taken along section line AA of FIG. 3C, in accordance with one embodiment of the subject invention. In this embodiment, mounting flange 310 resides above body 320, which supports drive system 330 including motor pulley 332, idler pulley 333, shaft pulley 334, and drive belt 331.

[0059] FIG. 3B shows a side view of a roller shaft 340 having slots 341 for suction airflow 342 to a vacuum source 343, according to one embodiment of the subject invention.

[0060] FIG. 3C shows a partial cross-sectional view of the end effector 300 of FIG. 3A along cross-sectional cut line AA, according to one embodiment of the subject invention. In this embodiment, a mounting flange 310 resides above a body 320, which supports a motor 360, a roller shaft 340, and a drive system 330, including a motor pulley 332, an idler pulley 333, a fastener 353, a shaft pulley 334, and a drive belt 331. Mounting holes 321 are used in certain embodiments to attach, secure, or orient the roller shaft 340 to the body 320 (e.g., by transverse pinning or clamping within a hole in the body 320). The roller shaft 340 is configured and adapted to deliver air at a proximal end 340a to a vacuum source 343. The roller unit 210 is supported on bearings 350 and 351 and secured in place by a fastener 352.

[0061] 3D shows a side view (not cut away) of end effector 300 according to one embodiment of the subject invention. In this embodiment, optional fasteners 322 can be seen securing roller shafts 340 in body 320.

[0062] 4A-4I illustrate an example of a robotic manipulator system 400 according to an embodiment of the subject invention to illustrate a process or flow of steps useful for placing, moving, and positioning a piece of fabric on a work surface using a single manipulator according to an embodiment of the subject invention. A robotic arm 410, supported by a frame 411 and equipped with a force (or torque) sensor 415, optionally with feedback from a camera or sensor 420, moves an end effector 300 to interact with a target piece of fabric 440 on a work surface 430. Initially, the end effector is moved by the manipulator so that the suction port contacts one end of the fabric (FIG. 4B). The force sensor 415 is used to monitor and adjust the contact force. The suction port acts to grip the contact area of ​​the fabric by providing an appropriate negative pressure or vacuum. The roller rotates to apply suction and roll up the piece of fabric, while the manipulator translates the end effector in a direction with a controllable displacement to roll up the piece of fabric without perturbing (e.g., wrinkling, loosening, slipping, twisting, or distorting) the rest of the fabric (e.g., as shown in Figures 5A-5D).

[0063] 5A-5D illustrate a fabric rolling operation using a single-manipulator system that synchronizes roller and end effector motion to remove wrinkles or slack in a target fabric piece, according to one embodiment of the subject invention. In certain embodiments, the manipulator motion 530 and roller rotation 520 can be synchronized in a manner that prevents, inhibits, removes, or reduces specific wrinkles or slack in the fabric during the rolling operation. For example, the camera 420 can be configured and adapted to detect a wrinkle or slack 510 in the target fabric piece within a field of view 421, and the motion 530 and rotation 520 can be controlled to apply a tension force T1 to a first portion 511 of the target fabric piece proximal to the wrinkle or slack 510. The tension force T1 and reaction force R1 together form a reaction force pair that acts to straighten the slack 510. The tension T1 is opposed by a resistance R1 created by the interaction of a second portion 512 of the target fabric piece distal to the wrinkle or slack 510, and the tension T1 can be controlled to handle the target fabric piece and reduce, eliminate, or control the wrinkle or slack 510.

[0064] After the appropriate amount of fabric is rolled up (e.g., as shown in FIG. 4D), the manipulator moves the end effector to the target position (e.g., as shown in FIGS. 4E-4F). A camera 420 can provide feedback across a field of view 421 to improve end effector control. The contact force against the work surface 430 is monitored and adjusted using a force sensor 415. The end effector finally unrolls the rolled up fabric with counter-rotating rollers. The approach illustrated by FIGS. 5A-5D is then applied in reverse, with the manipulator moving the end effector to unroll and lay the fabric flat using visual information gathered from the visual sensor system ( FIGS. 4G-4I ).

[0065] In certain embodiments, the visual sensor system includes a full-color sensor (e.g., an RGB digital camera). Supplemental lighting can also be used if necessary to improve the performance of the visual sensor system. The use of a monochrome camera is also contemplated, offering the benefits of reduced cost and complexity for reliable operation. A color or RGB camera can beneficially capture more visual information and more accurately determine the pose of the fabric piece (e.g., when the target fabric piece is colored).

[0066] By rolling up, the end effector can grip fabrics according to various embodiments of the subject invention having different dimensions within a certain range, such as dimensions that satisfy one or more of the following conditions: (i) the maximum fabric width is less than the length of the roller; and (ii) the manipulator's range of motion spans the fabric length during operation. Embodiments of the subject invention can be advantageously applied to thin, soft fabric materials that can easily deform to conform to the shape of the roller. In certain embodiments of the system, the end effector can reversibly change the gripped fabric between a flat state and a rolled-up state as needed (e.g., the target fabric piece shown in FIG. 5A is removed of wrinkles or slack in FIG. 5B, rolled up in FIG. 5C, and then returned to a flat state in FIG. 5D, optionally with a change in position and orientation).

[0067] Embodiments providing a single-manipulator robot, as exemplified above, can handle fabric using a single end effector and simplified tension control. Alternative embodiments of the invention provide robots consisting of two manipulators (i.e., dual-manipulator systems), each having at least one force (or torque) sensor and end effector that allow for improved tension control. Further alternative embodiments of the invention provide robots with three or more manipulators (i.e., multi-manipulator systems), each having at least one force (or torque) sensor and end effector that allow for multi-dimensional tension control.

[0068] 6A-6J illustrate the process of grasping, moving, and positioning a piece of fabric placed on a worktable using a dual-manipulator system according to one embodiment of the subject invention. In this embodiment, the end effector 300 with force sensors 415 can simultaneously (or in parallel, synchronously, asynchronously, or sequentially) reel in the fabric piece 440 from both sides in the same or similar manner as the single-manipulator method described above (e.g., FIGS. 6B-6D). The robot then lifts and moves the fabric piece to a target location (e.g., FIGS. 6E-6F). During the reeling, transporting, unfolding, and positioning of the fabric piece, tension is applied to the fabric piece and controlled using the force sensors 415 attached to the manipulators 410 and supported by the frame 411 (e.g., using the control device of FIG. 1). Visual feedback from the visual sensor system 420 can also accurately position the grasped fabric piece to a target pose (e.g., FIGS. 6G-6I). An advantageous feature of the provided dual manipulator system is its ability to grip a fabric piece from both sides and control the tension between them, so that the system can apply the appropriate tension to the gripped fabric piece, keeping the fabric piece flat and accurately positioned even when the fabric piece is subjected to other external forces, such as disturbances resulting from the sewing operation.

[0069] The combination of a dual manipulator configuration, provided end effectors and force sensors, tension control, and vision-based position control allows for precise handling of different shaped pieces of fabric without the use of fixtures.

[0070] In garment factories, pieces of fabric are typically cut from stacks of fabric material using cutting machines according to shapes defined by pre-set patterns. Picking the top piece of fabric from the stack of cut fabric can be difficult, especially when performed by automated equipment such as grippers. First, the weight of the stacked fabric can compress the fabrics and cause them to stick together, making them difficult to separate. Second, exposed threads at the cut edges of adjacent pieces of fabric can become entangled during the cutting process, resulting in tangles along the edges.

[0071] If multiple pieces of fabric are (accidentally) picked up by the gripper, the subsequent sewing operation will fail, resulting in a defective product. The ability to pick up "only one layer" remains a challenging task in the field of automated garment production.

[0072] While the above design has proven effective in performing pick and place of single fabrics, some difficulty has been encountered when used to pick only the top fabric from a stack, namely, that more than one fabric may be unintentionally picked up by the end effector at one time, since the stack of freshly cut fabrics (by the factory's cutting equipment) may be subject to fabric fiber entanglement and / or electrostatic effects that tend to cause multiple fabrics to "stick" together.

[0073] 7A to 7D show an end effector according to another embodiment that can solve the above problem. In the embodiment shown in FIGS. 7A to 7D, an air blow unit 740 is provided on the side of the suction roller. Although an air blow unit including an air blow roller 741 is shown in FIGS. 7A to 7D, the subject invention is not limited thereto. Instead of an air blow roller, the air blow unit 740 may include an array of nozzles, slits, tubes, etc., that can blow air from a positive pressure source. Hereinafter, the embodiment will be described using the example of the air blow roller 741.

[0074] 7A-7D, which show perspective views of end effector 700, end effector 700 includes a main body 710 having a mounting flange 720 formed thereon, the mounting flange 720 being configured to mount end effector 700 to a robot arm (not shown). The main body 710 is provided with a drive system 730 for driving a suction roller 731, the drive system 730 being similar to that shown in FIGS. 3-5, and including a motor pulley 732 driven by a motor (not shown), an idler pulley 734, a drive belt 735, and a shaft pulley 736 connected to suction roller 731. Thus, suction roller 731 can be rotated by motor 733 via drive belt 735. Suction roller 731 can be the same as suction roller 340 shown in FIG. 3 to pick up fabric, and therefore, the suction roller will not be described in detail.

[0075] In the main body 710, an air blowing unit 740 is provided to blow air in a selectable direction. The air blowing unit 740 includes an air blowing roller 741 provided on the side of the suction roller 731, and at least one opening (not shown) formed on its outer periphery through which air can be blown. The air blowing unit 740 further includes a motor pulley 742 rotated by a motor 743, an idler pulley 744, a drive belt 745, and a shaft pulley 746 connected to the air blowing roller 741. The opening on the air blowing roller can be a row of holes or slits provided in the air blowing roller to blow air from a positive pressure air source or the like. During operation, the air blowing roller can be rotated by the motor 743 via the drive belt 745 to change the direction of the blown air.

[0076] 8A to 8J, the operation of the end effector 700 will be described by way of example only, and it should be noted that the operation shown in Figures 8A to 8J is not intended to limit the present disclosure. Also, the end effector 700 will be described below by way of an example in which two end effectors 700 are provided in a mirror relationship and cooperate with each other, but the present disclosure is not intended to be limited thereto.

[0077] 1. As shown in Figures 8A-8B, when the suction roller 731 comes into physical contact with the top fabric 440 of the fabric stack, the air blow roller 741 begins to generate an outward airflow, causing the edges of the fabric to flap (as a mechanical disturbance). Such action acts to disentangle undesirable entanglements between adjacent fabrics caused by entanglement of loose fibers at the cut edges.

[0078] 2. By selecting a predetermined angle of the airflow relative to the plane of the fabric pieces, which can be determined empirically, the top fabric can be easily separated from the remaining fabric pieces and engaged by the suction roller.

[0079] 3. Next, as shown in FIG. 8C, the suction rollers suck the top piece (or layers) of fabric by suction and perform a rolling action to grip the fabric.

[0080] 4. Meanwhile, the air blowing roller rotates to substantially direct the airflow toward the second fabric in the stack, and the resulting positive air pressure stabilizes the second fabric, preventing it from following and getting caught in the top fabric (e.g., due to entanglement elsewhere) during the picking process, as shown in Figure 8D.

[0081] 5. Once the entire top fabric has been lifted and pulled away from the stack of fabrics, the air blow roller airflow can be stopped, as shown in Figure 8E.

[0082] 6. The airflow may remain stopped during the subsequent transfer and placement process, as shown in Figures 8F and 8G.

[0083] 7. As shown in Figures 8H to 8I, when the top cloth is moved to the predetermined target location, the top cloth will gradually unwind from the suction roller.

[0084] 8. Once the top fabric is completely unwound from the suction roller, as shown in FIG. 8J, the suction is stopped and the top fabric is separated from the suction roller as shown in FIG. 8J.

[0085] 9. The above cycle is repeated as the end effector picks up the next top cloth from the stack of cloths.

[0086] Therefore, by providing the suction roller with an air blowing roller, the top piece of fabric can be picked up easily and accurately from the pile of fabric material.

[0087] Similar to the previous embodiment shown in FIG. 6, two end effectors 700 can be provided to pick up or reel in the fabric from both sides to form a dual manipulator system, which will not be described in detail.

[0088] Although an air blowing roller is provided to blow out air, other air blowing units can be conceived by those skilled in the art, for example, the air blowing unit may include an array of nozzles that can be swung to blow air in different directions. Also, it is not essential that the air blowing roller has a circular cross section, and it can be of any shape as long as it can direct the air to the fabric in the appropriate direction, and the subject invention is not limited thereto.

[0089] The primary difference between the embodiments of the subject invention and related art (including, for example, the patents and commercial product disclosures mentioned above) lies in the robot system configuration. The embodiments provide a dual (or multi) robotic manipulator system, while the referenced related art uses a single-manipulator system. The dual-manipulator configuration can grip fabric from a selected edge or side and control the tension applied to the gripped fabric. The provided robotic system can keep the gripped fabric flat through real-time sensing of tension (i.e., internal force) or visual information, even when external forces are applied to the fabric during handling operations. Motion corrections can be implemented to maintain the desired shape state of the fabric. Such sophisticated tension and motion control is not achievable with other single-manipulator systems or systems using less sophisticated control systems and methods. The embodiments provide a feasible mechanical structure for a uniquely advantageous device.

[0090] In certain embodiments, an advantage of the provided reeling end effector is that it can pick up a piece of fabric material by suction in conjunction with coordinated motion between the end effector and the robotic manipulator so that the unwound piece of fabric is held in its original position. This facilitates a more accurate pick-and-place process for generally flexible fabrics by reducing the fabric piece's tendency to shift or slip during the pick-and-place process. This coordinated motion, enabled by the provided motion control, provides unique benefits for commercial sewing and other operations.

[0091] In certain embodiments, a transmission mechanism comprising pulleys and belts is used to precisely control the end effector, offering the advantage of precise and improved clearance around the roller, allowing for the use of smaller rollers for more precise control. In other embodiments, the rollers are driven directly by the motor from one end, offering the advantage of simplicity and cost savings, and larger rollers are advantageously used to allow contact with the fabric without motor interference.

[0092] material and method

[0093] All patents, patent applications, provisional applications, and publications referenced or cited herein are incorporated by reference in their entirety, including all figures and tables, to the extent not inconsistent with the explicit teachings of this specification.

[0094] In order that this disclosure may be more readily understood, certain terms are defined below and throughout the detailed description to provide guidance as to their meaning as used herein.

[0095] As used herein, "a," "an," "the," and similar terms used in the context of the subject invention shall be construed to include both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Thus, for example, a reference to "an arm" or "a hole" should be construed to include or encompass both a singular arm or a singular hole, and a plural arm and a plural hole, unless otherwise indicated or clearly contradicted by context.

[0096] As used herein, the terms "about" and "approximately" generally refer to an acceptable degree of error for the quantity measured given the nature or precision of the measurement. Exemplary degrees of error are within 20 percent (%), typically within 10%, and more typically within 5% of a given value or range of values.

[0097] As used herein, the term "and / or" should be understood to mean "either or both" of the features so conjoined, that is, elements that are conjunctively present in some cases and disjunctively present in other cases.

[0098] As used herein, the terms "comprising," "consisting of," and "consisting essentially of" are defined in accordance with their standard meanings. These terms may be substituted for one another herein to assign the specific meaning associated with each term.

[0099] As used herein, the term "or" should be understood to have the same meaning as "and / or" as defined above. For example, when dividing a list of items, "and / or" or "or" shall be interpreted to be inclusive, i.e., at least one of the items, but also including more than one, and optionally including additional unlisted items. Only terms expressly indicated to the contrary, such as "only one of" or "exactly one of," or when used in the claims with the term "consisting of," will refer to the inclusion of exactly one of the elements or listed elements. Generally, the term "or" as used herein shall not be interpreted as indicating exclusive alternatives (i.e., "one or the other, but not both") unless accompanied by exclusive terms such as "either," "one of," "only one of," or "exactly one of."

[0100] The following are examples illustrating procedures for carrying out the present invention. These examples should not be construed as limiting. All percentages are by weight and all solvent mixture proportions are by volume unless otherwise noted.

[0101] Example 1: Proposed Commercial Embodiments

[0102] product

[0103] One embodiment of the subject invention is purposefully designed to acquire, grasp, position, and release fabric material with the unique ability to control internal fabric forces during the handling process. When combined with a computer vision system, this embodiment facilitates the precise positioning required by fabric panel joining, interlining, and sewing operations, among other garment handling processes, in a manner that increases productivity, improves positioning accuracy, and reduces defects that lead to waste. Various commercialization opportunities exist for the current embodiment (and related embodiments), including, but not limited to, co-developing with or licensing to garment manufacturers, or marketing the system as a stand-alone product in collaboration with original equipment manufacturers (OEMs) that specialize in automation.

[0104] market

[0105] The commercial garment industry has yet to be fully impacted by modern robotics technology. One reason why the use of robots in the garment production sector is not widespread is that existing robotic devices that have been successfully adopted by other manufacturing sectors are not suited to handling textile materials, which are inherently soft and flexible and characterized by different textures. In other words, the way robots handle rigid parts in automotive factories is not compatible with the garment assembly process, as textiles tend to change shape when handled.

[0106] The clothing production process has remained largely unchanged since the invention of sewing machines and still relies heavily on human labor to complete most sewing and handling tasks. To lower production costs, clothing manufacturers are searching the world for cheaper labor and continue to relocate to regions or countries with lower wages, such as mainland China, Vietnam, and Bangladesh. Nevertheless, global labor shortages and rising wages are creating economic pressures, and automation technology will be the next frontier for clothing manufacturers to gain a competitive advantage. Major clothing manufacturers have expressed interest in upgrading their labor-intensive production processes with intelligent automation technology.

[0107] Competitive Analysis

[0108] The successful adoption of robots in the garment production sector depends on several key factors. First, whether the cost of the robotic device is economically justified compared to the cost of human labor for a range of routine production tasks. While labor wages in developing countries continue to rise, the selling price of industrial robots has recorded a declining trend according to published figures. Rising wages pose a pressing financial challenge for most garment manufacturers in the region, thus motivating them to pursue automation solutions that can keep garment production cost-effective.

[0109] Considering embodiments of the subject invention capable of handling pieces of fabric for various operations such as stacking and sewing, this can be considered the functional equivalent of a sewing worker working two shifts per day (or up to 24 hours) in a production cell. When combined with the costs associated with specially designed fixtures and the costs of providing food and subsidizing housing for workers not required by the system, the potential savings made possible by certain embodiments of the subject invention support the financial investment.

[0110] The production costs of the subject invention will vary depending on the engineering specifications and the actual volume of the robotic manipulators and components procured. Nevertheless, it is estimated that a reasonable selling price for such a system, including a dual robotic manipulator, hoisting end effector, and vision unit, would be within the realm of commercial feasibility, depending on target profit margins and distribution costs.

[0111] The second factor is whether the subject invention can handle fabric more effectively than other reported systems or commercial products on the market. The majority of robot end effectors identified in academic publications (e.g., those detailed above) employ mechanical grippers utilizing a "two-finger" configuration. This is largely due to their prevalence in conventional robotic systems and their readily available commercial availability. Despite the simplicity of their design, this type of end effector faces challenges in accurately positioning fabric because other portions of the fabric, particularly edges and corners, can sag and remain unconstrained. Adhesive grippers also suffer from the above problems, as well as the difficulty of releasing fabric from adhesive tape without disturbing the fabric's position.

[0112] Electroadhesive and airflow end effectors are obviously capable of binding larger areas of fabric, but have the drawback that the size of the end effector must be the same size as the fabric piece to avoid loose edges that interfere with the handling process, which can lead to a large end effector and limit the working range of the robotic system.

[0113] In contrast to the related art end effectors discussed above, embodiments of the subject invention address the problem by allowing the fabric material, once gripped, to be more fully constrained throughout the handling process. That is, there are no (or fewer or smaller) loose edges or corners, and fabric tension can be controlled to maintain the fabric in a stretched (e.g., semi-rigid) state, making fabric recognition and positioning more easily achievable by a robotic system. On the other hand, the length of the present end effector can be varied to accommodate a wider range of fabric panel sizes when needed without dramatically increasing the footprint occupied by the end effector as is the case with electroadhesive equivalents.

[0114] Another related art process (e.g., developed by Sewbo, Inc.) aims to transform garment pieces into more "rigid" objects that can then be more effectively handled and visualized by conventional robots. This process requires extra processing steps, including stiffening (stiffening the fabric with chemicals), de-rigidifying (rinsing with hot water), and drying, which inevitably adds significant processing time and cost to production and makes the overall process inefficient. This process has not yet proven commercially viable.

[0115] Embodiments of the subject invention offer a novel physical design and operating principles that differ from related art fabric handling robotic devices and systems. Embodiments offer distinct advantages over other systems in terms of fabric handling stability, positioning accuracy, and overall process efficiency. The current market situation reveals few established players in this field. Most garment production automation machinery is empirically developed by garment manufacturers for in-house use without expertise in robotics and computer vision. The emergence of innovations offered by the inventors meets the needs of garment manufacturers, who are constantly seeking effective automation solutions to enhance both quality and productivity.

[0116] Exemplary Embodiments

[0117] The present invention may be better understood with reference to certain exemplary embodiments, including, but not limited to, the following.

[0118] Embodiment 1. A fabric handling manipulator system for handling a target piece of fabric, comprising: a first robotic manipulator; a second robotic manipulator; and a first reeling end effector positioned by the first robotic manipulator, the first reeling end effector configured and adapted to grip a first end of the target fabric piece with a roller having a suction port; a second reeling end effector positioned by the second robotic manipulator, the second reeling end effector configured and adapted to grip a second end of the target fabric piece with a roller having a suction port; a first force sensor configured and adapted to sense a force applied to the first hoisting end effector; a second force sensor configured and adapted to sense a force applied to the second hoisting end effector; a visual sensor system configured and adapted to sense the orientation of the target fabric piece, the orientation of the first reeling end effector, and the orientation of the second reeling end effector; A cloth handling manipulator system comprising:

[0119] Embodiment 2. The cloth handling manipulator system of embodiment 1, comprising a controller configured and adapted to simultaneously control the orientation of the target cloth piece and the tension applied to the target cloth piece.

[0120] Embodiment 3. The cloth handling manipulator system of embodiment 2, which performs control via the first robotic manipulator and the second robotic manipulator in response to input from the visual sensor system and input from one or both of the first force sensor and the second force sensor.

[0121] Embodiment 4. a third robotic manipulator; and a third roll-up end effector positioned by the third robotic manipulator, the third roll-up end effector configured and adapted to grip a third end of the target fabric piece with a roller having a suction port; a third force sensor configured and adapted to sense a force applied to the third hoisting end effector; The cloth handling manipulator system according to any one of embodiments 1 to 3, comprising:

[0122] Embodiment 5. The cloth handling manipulator system of embodiment 4, which performs control via the first robotic manipulator, the second robotic manipulator, and the third robotic manipulator in response to input from the visual sensor system and input from two or more of the first force sensor, the second force sensor, and the third force sensor.

[0123] Embodiment 6. A cloth handling manipulator system according to any one of embodiments 1 to 3, wherein each of the first and second winding end effectors comprises a motor mounted on the winding end effector and configured to transmit torque through an appropriate transmission mechanism to control the rotation of the roller.

[0124] Embodiment 7. A cloth handling manipulator system according to any of embodiments 4 to 5, wherein each of the first winding end effector, the second winding end effector, and the third winding end effector comprises a motor mounted on the winding end effector and configured to transmit torque through an appropriate transmission mechanism to control the rotation of the roller.

[0125] Embodiment 8. A cloth handling manipulator system of any of embodiments 6 to 7, comprising a work table configured and adapted to support a target piece of cloth, and a frame configured and adapted to support a vision system and at least two robotic manipulators above the work table.

[0126] Embodiment 9. The first winding end effector includes at least a shaft portion fixed to a body of the end effector; a hollow tubular structure within the shaft portion; a roller portion rotatably attached to a shaft portion by a bearing; a suction port connecting the outer surface of the roller portion to a hollow tubular structure within the shaft portion; a vacuum source connected to one end of the shaft portion; 9. A cloth handling manipulator system according to any one of embodiments 1 to 8, wherein the cloth piece can be handled by a combination of suction and winding.

[0127] Embodiment 10. The first winding end effector includes at least a planar end effector mounting surface; a plurality of mounting holes in the planar end effector mounting surface arranged about a first axis of rotation extending through the end effector and generally perpendicular to the planar end effector mounting surface; a second rotation shaft along which the roller and the suction port are rotatably disposed; A cloth handling manipulator system according to embodiment 9, wherein the first axis of rotation intersects the second axis of rotation substantially perpendicularly, and when the roller is oriented substantially parallel to the working surface of the target piece of cloth, the roller remains substantially parallel to the working surface of the target piece of cloth even when the end effector is rotated by any amount about the first axis of rotation.

[0128] Embodiment 11. A method for handling a target piece of fabric, comprising: providing a target piece of fabric; providing a cloth handling manipulator system according to any one of embodiments 1 to 10; moving the first end effector with the first manipulator so that the suction port contacts the first end of the target fabric piece; applying a suitable negative pressure or vacuum to the suction port to grip the contact area of ​​the target fabric piece; and rotating the roller while translating the end effector in a direction by a controlled displacement to roll up the target fabric piece around the roller without perturbing the remainder of the target fabric piece.

[0129] Embodiment 12. further rotating the roller while translating the end effector in a direction by a controlled displacement to increase the rolled-up portion of the target fabric piece around the roller, thereby rolling up all or substantially all of the target fabric piece to leave the target fabric piece in a rolled-up state; Lifting the rolled up target fabric piece by operating the end effector; moving the end effector to a target position of the end effector by a manipulator; placing the target cloth piece rolled up by the end effector at a target position; The method of embodiment 11 includes a step of unfolding a portion of the rolled-up target fabric piece and positioning the target fabric piece by rotating the roller in a reverse direction while translating the end effector in a controlled amount of displacement in a certain direction so as to reduce the rolled-up portion of the target fabric piece around the roller.

[0130] Embodiment 13. Identifying, with a visual sensor system, irregularities on the surface of the target fabric piece due to twists, folds, or wrinkles; and rotating or counter-rotating the roller, translating the end effector, or both, in a direction with a controlled displacement to reduce or eliminate undulations on the surface of the target fabric piece.

[0131] Embodiment 14. Identifying undulations on a surface of the target fabric piece due to twists, folds, or wrinkles by monitoring fluctuations in the force measured by the first force sensor; and rotating or counter-rotating the roller, translating the end effector, or both, in a direction with a controlled displacement to reduce fluctuations in the force measured by the first force sensor and reduce or eliminate undulations on the surface of the target fabric piece.

[0132] Embodiment 15. A method for handling a target piece of fabric, comprising: providing a target piece of fabric; a first robotic manipulator; a second robotic manipulator; and a first reeling end effector positioned by the first robotic manipulator, the first reeling end effector configured and adapted to grip a first end of the target fabric piece with a first roller having a first suction port; a second reeling end effector positioned by the second robotic manipulator, the second reeling end effector configured and adapted to grip a second end of the target fabric piece with a second roller having a second suction port; a first force sensor configured and adapted to sense a force applied to the first hoisting end effector; a second force sensor configured and adapted to sense a force applied to the second hoisting end effector; a visual sensor system configured and adapted to sense a position of the target fabric piece, a position of the first reeling end effector, and a position of the second reeling end effector; a control device configured and adapted to simultaneously control the orientation of the target fabric piece and the tension applied to the target fabric piece via the first robotic manipulator and the second robotic manipulator in response to inputs from the visual sensor system and one or both of the first force sensor and the second force sensor. providing a fabric handling manipulator system; moving the first end effector with the first manipulator so that the first suction port contacts the first end of the target fabric piece; applying a suitable negative pressure or vacuum to a first suction port to grip a first end of the target fabric piece; rotating the first roller while translating the first end effector in a direction by a controlled displacement to roll up the target fabric piece around the first roller without perturbing the remainder of the target fabric piece; moving the second end effector with the second manipulator so that the second suction port contacts the second end of the target fabric piece; applying a suitable negative pressure or vacuum to the second suction port to grip the second end of the target fabric piece; and rotating the second roller while translating the second end effector in a direction by a controlled displacement to roll up the target fabric piece around the second roller without perturbing the remainder of the target fabric piece.

[0133] Embodiment 16. further rotating the first roller and the second roller, respectively, while translating the first end effector and the second end effector, respectively, by a controlled displacement amount in a certain direction to increase the rolled-up portion of the target fabric piece around the first roller and the second roller, respectively, thereby rolling up all or a further portion of the target fabric piece and placing the target fabric piece in a rolled-up state; lifting the rolled up target fabric piece by coordinated movement of the first end effector and the second end effector; moving the first end effector and the second end effector to a first end effector target position and a second end effector target position, respectively, by coordinated movement of the first manipulator and the second manipulator; placing the rolled-up target cloth piece at a target position by each of the first end effector and the second end effector; The method of embodiment 15 includes a step of unfolding a portion of the rolled-up target fabric piece and positioning the target fabric piece by rotating the first roller and the second roller in opposite directions while translating the first end effector and the second end effector, respectively, by a controlled amount of displacement in a certain direction so as to reduce the rolled-up portion of the target fabric piece around the rollers.

[0134] Embodiment 17. Identifying, with a visual sensor system, irregularities on the surface of the target fabric piece due to twists, folds, or wrinkles; and rotating or counter-rotating one or both of the first and second rollers, or translating one or both of the first and second end effectors, respectively, in a direction with a controlled displacement to reduce or eliminate undulations on the surface of the target fabric piece.

[0135] Embodiment 18. Identifying undulations on a surface of the target fabric piece due to twists, folds, or wrinkles by monitoring fluctuations in the forces measured by the first force sensor and the second force sensor, respectively; and rotating or counter-rotating the first and second rollers, respectively, and / or translating the first and second end effectors, respectively, in a direction with a controlled displacement amount so as to reduce fluctuations in the forces measured by the first and second force sensors, respectively, and to reduce or eliminate undulations on the surface of the target fabric piece.

[0136] Embodiment 19. During one or more of the lifting, moving, or placing steps, monitoring the forces measured by each of the first and second force sensors; The method of embodiment 16, further comprising the step of applying a target tension to the target piece of fabric by controlling the rotation of each of the first roller and the second roller and the translation of each of the first end effector and the second end effector.

[0137] Embodiment 20. The method of embodiment 19, including a step of controlling the tension applied to the target piece of fabric while performing a sewing operation on the target piece of fabric to a target tension.

[0138] Embodiment 21. The method of any one of the preceding embodiments 11 to 19, further comprising the step of blowing air in a direction to flutter the target fabric piece before providing an appropriate negative pressure or vacuum to the suction port to grip the contact area of ​​the target fabric piece.

[0139] Embodiment 22. 22. The method of embodiment 21, further comprising the step of changing the direction in which the air is blown.

[0140] Embodiment 23. A cloth handling manipulator system for handling a target piece of cloth, comprising: a first robotic manipulator; a second robotic manipulator; and a first reeling end effector positioned by the first robotic manipulator, the first reeling end effector configured and adapted to grip a first end of the target fabric piece with a first roller having a first suction port; a second reeling end effector positioned by the second robotic manipulator, the second reeling end effector configured and adapted to grip a second end of the target fabric piece with a second roller having a second suction port; a first force sensor configured and adapted to sense a force applied to the first hoisting end effector; a second force sensor configured and adapted to sense a force applied to the second hoisting end effector; a visual sensor system configured and adapted to sense a position of the target fabric piece, a position of the first reeling end effector, and a position of the second reeling end effector; and a control device configured and adapted to simultaneously control the posture of the target piece of fabric and the tension applied to the target piece of fabric via the first robotic manipulator and the second robotic manipulator in response to input from the visual sensor system and input from one or both of the first force sensor and the second force sensor.

[0141] Embodiment 24. The cloth handling manipulator system of embodiment 23, wherein each of the first winding end effector and the second winding end effector has a motor mounted on the winding end effector and configured to control the rotation of the roller by transmitting torque through an appropriate transmission mechanism, and the cloth handling manipulator system comprises a work table configured and adapted to support the target cloth piece, and a frame configured and adapted to support a vision system and at least two robotic manipulators above the work table.

[0142] Embodiment 25. The first winding end effector includes at least a shaft portion fixed to a body of the end effector; a hollow tubular structure within the shaft portion; a roller portion rotatably attached to a shaft portion by a bearing; a suction port connecting the outer surface of the roller portion to a hollow tubular structure within the shaft portion; a vacuum source connected to one end of the shaft portion; 24. A cloth handling manipulator system according to embodiment 23, capable of handling cloth pieces by a combination of suction and winding.

[0143] Embodiment 26. The first winding end effector includes at least a planar end effector mounting surface; a plurality of mounting holes in the planar end effector mounting surface arranged about a first axis of rotation extending through the end effector and perpendicular to the planar end effector mounting surface; a second rotation shaft along which the roller and the suction port are rotatably disposed; A cloth handling manipulator system according to embodiment 23, wherein the first axis of rotation intersects the second axis of rotation substantially perpendicularly, and when the roller is oriented substantially parallel to the working surface of the target piece of cloth, the roller remains substantially parallel to the working surface of the target piece of cloth even when the end effector is rotated about the first axis of rotation by any amount.

[0144] Embodiment 27. The first winding end effector and / or the second winding end effector are: 27. The cloth handling manipulator system according to any one of embodiments 23 to 26, further comprising an air blowing unit configured to blow air in a certain direction.

[0145] Embodiment 28. A cloth handling manipulator system according to embodiment 27, wherein the air blowing unit comprises an air blowing roller, and at least one opening for blowing air is formed on the outer periphery of the air blowing roller.

[0146] Embodiment 29: A cloth handling manipulator system of embodiment 28, in which the air blowing roller can be rotated by a motor installed in the end effector, and the direction in which air is blown out can be changed by transmitting torque through a transmission mechanism.

[0147] While the subject invention is illustrated and described herein with reference to preferred embodiments and specific examples thereof, it will be readily apparent to those skilled in the art that other embodiments and examples can perform similar functions and / or achieve similar results.

[0148] It is to be understood that the examples and embodiments described herein are for illustrative purposes only, and that various modifications or changes in light thereof will be suggested to those skilled in the art and are to be included within the spirit and scope of this application and the scope of the appended claims. Furthermore, any element or limitation of an invention or embodiment thereof disclosed herein may be combined (individually or in any combination) with any other invention or embodiment thereof disclosed herein, or with any and / or all other elements or limitations, and all such combinations are contemplated within the scope of the invention, including, but not limited to, the invention.

[0149] References

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[0152] 2.J.Stria et al.,”Garment perception and its folding using a dual-arm robot,”2014 IEEE / RSJ International Conference on Intelligent Robots and Systems,2014,pp.61-67,doi:10.1109 / IROS.2014.6942541.

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[0154] 3.L.Sun,G.Aragon-Camarasa,S.Rogers and J.P.Siebert,”Accurate garment surface analysis using an active stereo robot head with application to dual-arm flattening,”2015 IEEE International Conference on Robotics and Automation(ICRA),2015,pp.185-192,doi:10.1109 / ICRA.2015.7138998.

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[0158] 5.M.Shibata and S.Hirai,”Fabric manipulation utilizing contacts with the environment,”2012 IEEE International Conference on Automation Science and Engineering(CASE),2012,pp.442-447,doi:10.1109 / CoASE.2012.6386350.

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[0160] 6.M.Aranda,J.Antonio Corrales Ramon,Y.Mezouar,A.Bartoli and E.Ozgur,”Monocular Visual Shape Tracking and Servoing for Isometrically Deforming Objects,”2020 IEEE / RSJ International Conference on Intelligent Robots and Systems(IROS),2020,pp.7542-7549,doi:10.1109 / IROS45743.2020.9341646.

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Claims

1. 1. A fabric handling manipulator system for handling a target piece of fabric, comprising: a first robotic manipulator; a second robotic manipulator; and a first hoisting end effector positioned by the first robotic manipulator, the first hoisting end effector configured and adapted to grip a first end of the target fabric piece with a roller having a suction port; a second roll-up end effector positioned by the second robotic manipulator, the second roll-up end effector configured and adapted to grip a second end of the target fabric piece with a roller having a suction port; a first force sensor configured and adapted to sense a force applied to the first hoisting end effector; a second force sensor configured and adapted to sense a force applied to the second hoisting end effector; a visual sensor system configured and adapted to sense a position of the target fabric piece, a position of the first reeling end effector, and a position of the second reeling end effector; A cloth handling manipulator system comprising:

2. 10. The cloth handling manipulator system of claim 1, comprising a controller constructed and adapted to simultaneously control the orientation of the target piece of fabric and the tension applied to the target piece of fabric.

3. 3. The cloth handling manipulator system of claim 2, wherein said control is exercised via said first robotic manipulator and said second robotic manipulator in response to input from said vision sensor system and input from one or both of said first force sensor and said second force sensor.

4. a third robotic manipulator; and a third roll-up end effector positioned by the third robotic manipulator, the third roll-up end effector configured and adapted to grip a third end of the target fabric piece with a roller having a suction port; a third force sensor configured and adapted to sense a force applied to the third hoisting end effector; The cloth handling manipulator system according to any one of claims 1 to 3, comprising:

5. 5. The cloth handling manipulator system of claim 4, wherein the control is exercised via the first robotic manipulator, the second robotic manipulator, and the third robotic manipulator in response to input from the vision sensor system and inputs from two or more of the first force sensor, the second force sensor, and the third force sensor.

6. 4. The cloth handling manipulator system according to claim 1, wherein each of the first and second hoisting end effectors comprises a motor mounted on the hoisting end effector and configured to transmit torque through a transmission mechanism to control the rotation of the roller.

7. 6. The cloth handling manipulator system according to claim 4, wherein each of the first hoisting end effector, the second hoisting end effector, and the third hoisting end effector comprises a motor mounted on the hoisting end effector and configured to transmit torque through an appropriate transmission mechanism to control the rotation of the roller.

8. 8. The cloth handling manipulator system of claim 6, comprising: a work table configured and adapted to support the target piece of cloth; and a frame configured and adapted to support the vision system and at least two robotic manipulators above the work table.

9. the first hoisting end effector includes at least a shaft portion fixed to the body of the end effector; a hollow tubular structure within the shaft portion; the roller portion rotatably attached to the shaft portion by a bearing; the suction port connecting the outer surface of the roller portion to the hollow tubular structure within the shaft portion; a vacuum source connected to one end of the shaft portion; A cloth handling manipulator system according to any one of claims 1 to 8, capable of handling pieces of cloth by a combination of suction and winding.

10. the first hoisting end effector includes at least a planar end effector mounting surface; a plurality of mounting holes in the planar end effector mounting surface arranged about a first axis of rotation extending through the end effector and generally perpendicular to the planar end effector mounting surface; a second rotation shaft along which the roller and the suction port are rotatably disposed, 10. The cloth handling manipulator system of claim 9, wherein the first axis of rotation is generally perpendicular to and transverse to the second axis of rotation, and when the roller is oriented generally parallel to the work surface of the target fabric piece, the roller remains generally parallel to the work surface of the target fabric piece even when the end effector is rotated about the first axis of rotation by any amount.

11. The first hoisting end effector and / or the second hoisting end effector are The cloth handling manipulator system according to any one of claims 1 to 10, further comprising an air blowing unit configured to blow air in a direction.

12. 12. The cloth handling manipulator system according to claim 11, wherein the air blowing unit comprises an air blowing roller, and at least one opening for blowing air is formed on the outer periphery of the air blowing roller.

13. 13. The cloth handling manipulator system of claim 12, wherein the air blowing roller is rotatable to change the direction of the blown air.

14. 1. A method of handling a target piece of fabric, comprising: providing the target piece of fabric; Providing a cloth handling manipulator system according to any one of claims 1 to 13; moving the first end effector with the first manipulator so that the suction port contacts a first end of the target fabric piece; applying a suitable negative pressure or vacuum to the suction port to grip the contact area of ​​the target fabric piece; rotating the roller while translating the end effector in a direction with a controlled displacement so as to roll up the target fabric piece around the roller without perturbing the remainder of the target fabric piece; A method comprising:

15. further rotating the roller while translating the end effector in a direction by a controlled displacement to increase the rolled-up portion of the target fabric piece around the roller, thereby rolling up all or substantially all of the target fabric piece and leaving the target fabric piece in a rolled-up state; lifting the rolled up target piece of fabric by operation of the end effector; moving the end effector to a target position of the end effector by the manipulator; placing the rolled up target cloth piece at a target position by the end effector; and counter-rotating the roller while translating the end effector in a direction by a controlled displacement amount to spread a portion of the rolled-up target fabric piece and position the target fabric piece so as to reduce the rolled-up portion of the target fabric piece around the roller.

16. identifying, with the visual sensor system, irregularities on the surface of the target fabric due to twists, folds, or wrinkles; and rotating or counter-rotating the roller, translating the end effector, or both, in a direction with a controlled displacement to reduce or eliminate undulations on the surface of the target fabric piece.

17. Identifying undulations on the surface of the target fabric piece due to twists, folds, or wrinkles by monitoring fluctuations in the force measured by the first force sensor; and rotating or counter-rotating the roller, translating the end effector, or both, in a direction by a controlled displacement to reduce fluctuations in the force measured by the first force sensor and reduce or eliminate undulations on the target fabric surface.

18. 18. The method of any one of claims 14 to 17, further comprising blowing air in a direction to flap the target piece of fabric before applying an appropriate negative pressure or vacuum to the suction port to grip the contact area of ​​the target piece of fabric.

19. The step of changing the direction in which the air is blown out 20. The method of claim 18, further comprising:

20. 1. A method of handling a target piece of fabric, comprising: providing the target piece of fabric; a first robotic manipulator; a second robotic manipulator; and a first reeling end effector positioned by the first robotic manipulator, the first reeling end effector configured and adapted to grip a first end of the target fabric piece with a first roller having a first suction port; a second roll-up end effector positioned by the second robotic manipulator, the second roll-up end effector configured and adapted to grip a second end of the target fabric piece with a second roller having a second suction port; a first force sensor configured and adapted to sense a force applied to the first hoisting end effector; a second force sensor configured and adapted to sense a force applied to the second hoisting end effector; a visual sensor system configured and adapted to sense a position of the target piece of fabric, a position of the first reeling end effector, and a position of the second reeling end effector; a control device configured and adapted to simultaneously control the orientation of the target cloth piece and the tension applied to the target cloth piece via the first robotic manipulator and the second robotic manipulator in response to input from the visual sensor system and input from one or both of the first force sensor and the second force sensor. providing a fabric handling manipulator system; moving the first end effector with the first manipulator so that the first suction port contacts the first end of the target fabric piece; applying negative pressure or vacuum to the first suction port to grip the first end of the target fabric piece; rotating the first roller while translating the first end effector in a direction by a controlled displacement to roll up the target fabric piece around the first roller without perturbing the remainder of the target fabric piece; moving the second end effector with the second manipulator so that the second suction port contacts the second end of the target fabric piece; applying a suitable negative pressure or vacuum to the second suction port to grip the second end of the target fabric piece; rotating the second roller while translating the second end effector in a direction by a controlled displacement to roll up the target fabric piece around the second roller without perturbing the remainder of the target fabric piece; A method comprising:

21. further rotating the first roller and the second roller, respectively, while translating the first end effector and the second end effector, respectively, by a controlled amount of displacement in a certain direction to increase the rolled-up portion of the target fabric piece around the first roller and the second roller, respectively, thereby rolling up all or a further portion of the target fabric piece and placing the target fabric piece in a rolled-up state; lifting the rolled up target fabric piece by coordinated movement of the first end effector and the second end effector; moving the first end effector and the second end effector to a first end effector target position and a second end effector target position, respectively, by coordinated operation of the first manipulator and the second manipulator; placing the rolled-up target cloth piece at a target position by each of the first end effector and the second end effector; and rotating the first roller and the second roller, respectively, in opposite directions while translating the first end effector and the second end effector, respectively, by a controlled amount of displacement in a certain direction to spread a portion of the rolled-up target fabric piece and position the target fabric piece so as to reduce the rolled-up portion of the target fabric piece around the rollers.

22. identifying, with the visual sensor system, irregularities on the surface of the target fabric due to twists, folds, or wrinkles; and rotating or counter-rotating one or both of the first roller and the second roller, and / or translating one or both of the first end effector and the second end effector, respectively, in a direction with a controlled displacement to reduce or eliminate undulations on the surface of the target fabric piece.

23. Identifying undulations on the surface of the target fabric piece due to twists, folds, or wrinkles by monitoring fluctuations in the forces measured by the first force sensor and the second force sensor; and rotating or counter-rotating the first and second rollers, respectively, and / or translating the first and second end effectors, respectively, in a direction by a controlled displacement amount to reduce fluctuations in the forces measured by the first and second force sensors, respectively, and to reduce or eliminate undulations on the target fabric surface.

24. During one or more of the lifting, moving, or placing steps, monitoring the forces measured by each of the first and second force sensors; and applying a target tension to the target piece of fabric by controlling rotation of the first roller and the second roller, respectively, and translation of the first end effector and the second end effector, respectively.

25. 25. The method of claim 24, further comprising controlling tension applied to the target piece of fabric during a sewing operation on the target piece of fabric so as to achieve the target tension.

26. The first winding end effector and / or the second winding end effector further include an air blowing unit configured to blow air in a certain direction; 25. The method of claim 20, further comprising blowing air in a direction to flutter the target piece of fabric before providing the negative pressure or vacuum to the first suction port and / or the second suction port.

27. 27. The method of claim 26, further comprising the step of changing the direction of the air blown after lifting the rolled-up target piece of fabric so that the air is blown toward a piece of fabric directly below the rolled-up target piece of fabric.

28. 1. A fabric handling manipulator system for handling a target piece of fabric, comprising: a first robotic manipulator; a second robotic manipulator; and a first reeling end effector positioned by the first robotic manipulator, the first reeling end effector configured and adapted to grip a first end of the target fabric piece with a first roller having a first suction port; a second roll-up end effector positioned by the second robotic manipulator, the second roll-up end effector configured and adapted to grip a second end of the target fabric piece with a second roller having a second suction port; a first force sensor configured and adapted to sense a force applied to the first hoisting end effector; a second force sensor configured and adapted to sense a force applied to the second hoisting end effector; a visual sensor system configured and adapted to sense a position of the target piece of fabric, a position of the first reeling end effector, and a position of the second reeling end effector; a control device configured and adapted to simultaneously control the orientation of the target cloth piece and the tension applied to the target cloth piece via the first robotic manipulator and the second robotic manipulator in response to inputs from the visual sensor system and one or both of the first force sensor and the second force sensor; A cloth handling manipulator system comprising:

29. 29. The fabric handling manipulator system of claim 28, wherein each of the first and second hoisting end effectors comprises a motor mounted to the hoisting end effector and configured to transmit torque through a suitable transmission mechanism to control rotation of the roller; a work table configured and adapted to support the target fabric piece; and a frame configured and adapted to support the vision system and at least two robotic manipulators above the work table.

30. the first hoisting end effector includes at least a shaft portion fixed to the body of the end effector; a hollow tubular structure within the shaft portion; the roller portion rotatably attached to the shaft portion by a bearing; the suction port connecting the outer surface of the roller portion to the hollow tubular structure within the shaft portion; a vacuum source connected to one end of the shaft portion; 30. A fabric handling manipulator system according to claim 29, capable of handling pieces of fabric by a combination of suction and reeling.

31. the first hoisting end effector includes at least a planar end effector mounting surface; a plurality of mounting holes in the planar end effector mounting surface arranged about a first axis of rotation extending through the end effector and perpendicular to the planar end effector mounting surface; a second rotation shaft along which the roller and the suction port are rotatably disposed, 31. The cloth handling manipulator system of claim 30, wherein the first axis of rotation is generally perpendicular to and transverse to the second axis of rotation, and when the roller is oriented generally parallel to the work surface of the target fabric piece, the roller remains generally parallel to the work surface of the target fabric piece even when the end effector is rotated about the first axis of rotation by any amount.

32. The first hoisting end effector and / or the second hoisting end effector are The cloth handling manipulator system according to any one of claims 28 to 31, further comprising an air blowing unit configured to blow air in a direction.

33. 33. The cloth handling manipulator system according to claim 32, wherein said air blowing unit comprises an air blowing roller, and at least one opening for blowing air is formed on the outer periphery of said air blowing roller.

34. 34. The cloth handling manipulator system according to claim 33, wherein the air blowing roller is rotatable by a motor installed in the end effector, and the direction in which the air is blown out can be changed by transmitting torque through a transmission mechanism.

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